2. 6FKOXPEHUJHU
Eclipse 100 User Course Page 2 of 499 08/04/99
CONTENTS
Introduction...........................................................................................................................................................13
Purpose .............................................................................................................................................................14
What is Reservoir Simulation...........................................................................................................................16
How Does the Model Relate to the Reservoir ..................................................................................................18
Why Reservoir Simulation?..............................................................................................................................22
Why ECLIPSE?................................................................................................................................................24
ECLIPSE Features............................................................................................................................................26
How ECLIPSE Works......................................................................................................................................28
Static Reservoir Description.............................................................................................................................32
PVT and Rock Data..........................................................................................................................................36
Initialisation Data..............................................................................................................................................38
Equilibration.................................................................................................................................................39
Enumeration .................................................................................................................................................39
Restart Runs .................................................................................................................................................39
Well Data..........................................................................................................................................................42
Reservoir Simulation with ECLIPSE ...............................................................................................................44
How to Use the Manuals...................................................................................................................................46
File Organisation and Structure ............................................................................................................................49
ECLIPSE Input / Output Structure ...................................................................................................................50
ECLIPSE Output Files......................................................................................................................................52
ECLIPSE Output Styles....................................................................................................................................56
Output File Names............................................................................................................................................60
File Extensions and Case..............................................................................................................................61
How to Alter Personal Default File Extensions and Case ............................................................................62
Output Styles................................................................................................................................................63
File Locations ...................................................................................................................................................64
Utility Macros...................................................................................................................................................66
@convert ......................................................................................................................................................67
@copyconfig ................................................................................................................................................67
@ecl2avs ......................................................................................................................................................67
@expand.......................................................................................................................................................67
@extract .......................................................................................................................................................67
@flexstart.....................................................................................................................................................67
@frame.........................................................................................................................................................67
@lmdown.....................................................................................................................................................68
@lmhostid ....................................................................................................................................................68
@lmstat ........................................................................................................................................................68
Input Data File Structure ..................................................................................................................................70
Data File Syntax ...............................................................................................................................................74
Keyword Syntax ...............................................................................................................................................76
Any Section Keywords.....................................................................................................................................80
INCLUDE ....................................................................................................................................................81
COLUMNS ..................................................................................................................................................81
DEBUG........................................................................................................................................................81
NOECHO .....................................................................................................................................................81
ECHO...........................................................................................................................................................81
EXTRAPMS.................................................................................................................................................81
OPTIONS.....................................................................................................................................................81
MESSAGES.................................................................................................................................................81
NOWARN....................................................................................................................................................82
FORMFEED.................................................................................................................................................82
LOAD...........................................................................................................................................................82
The RUNSPEC Section ........................................................................................................................................83
Purpose of the RUNSPEC Section ...................................................................................................................84
How to Convert Fixed Format RUNPSEC to Free Format ..........................................................................86
RUNSPEC Keywords and Switches.................................................................................................................88
Commonly used RUNSPEC keywords and switches...................................................................................89
3. 6FKOXPEHUJHU
Eclipse 100 User Course Page 3 of 499 08/04/99
Data Files with No RUNSPEC.........................................................................................................................92
How to Create a Fast Restart........................................................................................................................93
System Usage........................................................................................................................................................95
Basic Unix Commands .....................................................................................................................................96
The vi Editor...................................................................................................................................................100
The GRID Section...............................................................................................................................................105
Purpose of the GRID Section..........................................................................................................................106
Data Reading Convention...............................................................................................................................110
Cartesian Grids...........................................................................................................................................110
Radial Grids................................................................................................................................................110
Geometrical Representations..........................................................................................................................114
Block Centred Geometry............................................................................................................................115
Corner Point Geometry ..............................................................................................................................116
Corner Point versus Block Centred Geometry ...........................................................................................117
Block-Centred Geometry Example.................................................................................................................118
Corner Point Geometry Example....................................................................................................................122
Grid Cell Properties........................................................................................................................................124
How to Assign Grid Cell Properties ...............................................................................................................126
How to Set One Property Value per Grid Cell ...........................................................................................127
How to Set Grid Cell Property Values Using Boxes..................................................................................128
How to Set Grid Cell Property Values Using EQUALS ............................................................................128
How to Copy Grid Cell Property Data .......................................................................................................130
How to Add, Subtract, Multiply and Divide Grid Cell Property Data .......................................................131
How to Multiply Cell Pore Volume Using MULTPV................................................................................132
How to Copy Data From one Portion of the Grid to Another using COPYBOX.......................................132
How to Read Data from Another File Using INCLUDE............................................................................133
How to Deactivate Cells Using ACTNUM ................................................................................................133
Transmissibility Conventions .........................................................................................................................136
Cartesian Grid Transmissibility......................................................................................................................138
OLDTRAN Transmissibility Calculation...................................................................................................139
OLDTRANR Transmissibility Calculation................................................................................................142
NEWTRAN Transmissibility Calculation..................................................................................................144
Radial Grid Transmissibility...........................................................................................................................146
Shale Modelling..............................................................................................................................................150
Modelling shales explicitly as grid layers ..................................................................................................151
Modelling shales by incorporation into larger sand cells ...........................................................................151
Modelling shales as gaps between sand layers...........................................................................................152
Transmissibility Modification.........................................................................................................................154
Non-Neighbour Connections..........................................................................................................................160
NNC Generation across Faults .......................................................................................................................162
NNC Generation across Pinchouts .................................................................................................................164
NNC Generation at Local Grid Refinements..................................................................................................166
NNCs in Dual Porosity Models ......................................................................................................................168
NNC Generation in Aquifers..........................................................................................................................170
NNC Generation in Radial Models.................................................................................................................172
Radial Models.................................................................................................................................................174
Output Control................................................................................................................................................178
GRIDFILE..................................................................................................................................................179
NOGGF......................................................................................................................................................179
INIT............................................................................................................................................................179
RPTGRID...................................................................................................................................................179
BOUNDARY .............................................................................................................................................180
Grid Section Keyword Summary....................................................................................................................182
Cartesian Geometry....................................................................................................................................183
Radial Geometry.........................................................................................................................................183
Cell Properties............................................................................................................................................183
Pinchouts & Deactivation...........................................................................................................................184
Transmissibility..........................................................................................................................................184
Transmissibility modification.....................................................................................................................184
Faults..........................................................................................................................................................184
Diffusivity ..................................................................................................................................................185
4. 6FKOXPEHUJHU
Eclipse 100 User Course Page 4 of 499 08/04/99
Numerical Aquifers....................................................................................................................................185
Operators....................................................................................................................................................185
Dual Porosity / Permeability ......................................................................................................................185
Flux Boundary Option................................................................................................................................186
Independent Reservoir Regions..................................................................................................................186
Thermal Option ..........................................................................................................................................186
Vertical Equilibrium Option.......................................................................................................................186
Miscellaneous and Output..........................................................................................................................186
The EDIT Section ...............................................................................................................................................189
Purpose of the EDIT Section ..........................................................................................................................190
Edit Section Keyword Summary ....................................................................................................................192
The PROPS Section – Fluid Properties...............................................................................................................195
Purpose of Fluid Properties.............................................................................................................................196
Black Oil Overview........................................................................................................................................198
Black oil versus compositional simulation .....................................................................................................202
The Oil Equation of State ...............................................................................................................................204
Dead Oil PVT Data Entry Using PVDO.........................................................................................................208
Dead Oil PVT Data Entry Using PVCDO......................................................................................................210
Live Oil PVT Data Entry Using PVTO..........................................................................................................212
Live Oil PVT Data Entry Using PVCO..........................................................................................................214
The Gas Equation of State ..............................................................................................................................216
Dry Gas Data entry Using PVZG ...................................................................................................................220
Dry Gas PVT Data Entry Using PVDG..........................................................................................................222
Wet Gas PVT Data Entry Using PVTG..........................................................................................................224
The Water Equation of State...........................................................................................................................226
Reference Densities ........................................................................................................................................228
Black Oil Model Phase Options......................................................................................................................230
Three-phase simulations.............................................................................................................................231
Two-phase simulations...............................................................................................................................231
Single phase simulations ............................................................................................................................232
Defining Multiple PVT Types using PVT Regions........................................................................................234
How to define multiple PVT types using PVT regions ..............................................................................235
Defining Multiple PVT Types using API Tracking........................................................................................238
How to Implement API Tracking...............................................................................................................239
Example API Tracking Data ......................................................................................................................240
Rock Compressibility .....................................................................................................................................244
Saturation Functions and Endpoint Scaling ........................................................................................................247
Purpose of Saturation Functions.....................................................................................................................248
Saturation Functions.......................................................................................................................................250
Saturation Function Definition...................................................................................................................251
Saturation Function Keyword Family 1 .....................................................................................................252
Saturation Function Keyword Family 2 .....................................................................................................253
Three-Phase Relative Permeability.................................................................................................................256
Eclipse Default ...........................................................................................................................................257
Modified STONE1 .....................................................................................................................................257
Modified STONE2 .....................................................................................................................................257
Saturation Function Scaling............................................................................................................................258
Endpoint Scaling.............................................................................................................................................260
How to Implement Endpoint Scaling .........................................................................................................261
2-Point and 3-Point Endpoint Scaling ........................................................................................................263
Limiting three-Point Endpoint Scaling.......................................................................................................264
Vertical scaling...............................................................................................................................................266
Capillary Pressure Scaling..............................................................................................................................270
Vertical Capillary Pressure Scaling............................................................................................................271
Horizontal Capillary Pressure Scaling........................................................................................................271
The Leverett J Function..............................................................................................................................271
Pressure Dependent Interfacial Tension.....................................................................................................272
Output Control................................................................................................................................................274
The REGIONS Section .......................................................................................................................................277
Purpose of the REGIONS Section..................................................................................................................278
Regions Keyword Types.................................................................................................................................280
5. 6FKOXPEHUJHU
Eclipse 100 User Course Page 5 of 499 08/04/99
Region definition keywords .......................................................................................................................281
Fluid in Place Regions................................................................................................................................282
Directional Keywords.................................................................................................................................283
Operators....................................................................................................................................................283
Output Controls..........................................................................................................................................283
The SOLUTION Section ....................................................................................................................................285
Purpose of the SOLUTION Section ...............................................................................................................286
Equilibration...................................................................................................................................................288
Initial Phase Saturation...............................................................................................................................289
Initial Phase Saturation in the Transition Zone ..........................................................................................290
EQUIL Keyword Usage..................................................................................................................................292
Block Centre Equilibration.............................................................................................................................294
Level and Tilted Block Fine Grid Equilibration.............................................................................................296
Quiescence .................................................................................................................................................297
Mobile Fluid Correction .................................................................................................................................300
Transition Zone Endpoint Variation...............................................................................................................304
Matching Initial Water Distribution ...............................................................................................................306
Enumeration....................................................................................................................................................308
Initial Solution Ratios.....................................................................................................................................310
Restarts ...........................................................................................................................................................312
How to Create a Full Restart Run...............................................................................................................315
How to Create a Fast Restart Run ..............................................................................................................316
Flexible vs. Fast Restarts............................................................................................................................317
Output Control................................................................................................................................................320
Aquifer Modelling...............................................................................................................................................323
Aquifer Modelling Facilities...........................................................................................................................324
Grid Cell Aquifers ..........................................................................................................................................326
Numerical Aquifers ........................................................................................................................................328
Fetkovich Aquifers .........................................................................................................................................332
Carter-Tracy Aquifers.....................................................................................................................................336
Flux Aquifers..................................................................................................................................................340
Output Control................................................................................................................................................342
The SUMMARY Section....................................................................................................................................345
Purpose of the SUMMARY Section...............................................................................................................346
Additional Parameters ....................................................................................................................................350
Field quantities...........................................................................................................................................351
Region quantities........................................................................................................................................351
Group quantities .........................................................................................................................................351
Well quantities............................................................................................................................................351
Block quantities..........................................................................................................................................351
Connection quantities.................................................................................................................................352
Output Controls and Additional Keywords ....................................................................................................354
Anisotropic relative permeability keywords...............................................................................................355
Reservoir Volumes.....................................................................................................................................355
Oil Recovery Efficiencies...........................................................................................................................355
Oil Recovery Mechanisms .........................................................................................................................355
Analytic Aquifer Quantities .......................................................................................................................355
Brine Option Keywords..............................................................................................................................355
Simulator Performance Keywords .............................................................................................................356
Output Control Keywords ..........................................................................................................................356
The SCHEDULE Section – History Matching....................................................................................................357
Purpose of the SCHEDULE Section ..............................................................................................................358
History Matching Versus Prediction...............................................................................................................360
History Matching........................................................................................................................................361
Prediction ...................................................................................................................................................361
History Match SCHEDULE Section Structure...............................................................................................364
VFP Curve Specification ................................................................................................................................368
VFP Table Generation................................................................................................................................369
Production Well VFP Table Structure........................................................................................................370
Injection Well VFP Table Structure...........................................................................................................370
Pipeline Segment VFP Table Structure......................................................................................................371
6. 6FKOXPEHUJHU
Eclipse 100 User Course Page 6 of 499 08/04/99
VFP Table Usage in ECLIPSE...................................................................................................................371
How to Set up VFP Tables in Eclipse ........................................................................................................372
Drilling a Well: WELSPECS..........................................................................................................................374
Gas Flow in Wells ..........................................................................................................................................380
Low Pressure gas wells ..............................................................................................................................381
The Russel Goodrich Equation...................................................................................................................381
The Gas Pseudopressure.............................................................................................................................382
Standard Inflow Equation...........................................................................................................................383
Connection Specification: COMPDAT ..........................................................................................................384
Partial Completion: COMPRP........................................................................................................................392
Partial Completion with VE: COMPVE.........................................................................................................396
Measured Well Production Rates: WCONHIST ............................................................................................402
Well Injection Rates: WCONINJE.................................................................................................................406
Simulator Control: TUNING, TUNINGL and NEXTSTEP...........................................................................410
Output Control : RPTSCHED and RPTRST ..................................................................................................414
Re-Solution and Re-Evaporation Rates: DRSDT & DRVDT ........................................................................418
Simulation Advance and Termination: DATES, TSTEP & END ..................................................................420
Well Performance Matching...........................................................................................................................422
Productivity Index Adjustment...................................................................................................................423
Drawdown Adjustment...............................................................................................................................424
Manual Workovers, Rate and PI Modifications..............................................................................................426
Manually Opening and Shutting Wells or Connections: WELOPEN ........................................................427
Completion Workovers: COMPDAT.........................................................................................................427
Partially Penetrated Completion Workovers: COMPRP, COMPVE .........................................................427
Modifying Well Targets: WELTARG........................................................................................................427
Well Pi Modification: WELPI and WPIMULT..........................................................................................428
Modelling Well Stimulation by means other than Skin Factor Change .....................................................428
The SCHEDULE Section – Prediction ...............................................................................................................431
Prediction SCHEDULE Section Structure......................................................................................................432
Setting Well Target Rates: WCONPROD ......................................................................................................436
Economic Limit Definition.............................................................................................................................440
Well Economic Limits, Automatic Workovers and Cutbacks........................................................................442
Well Economic Limits................................................................................................................................443
Connection Economic Limits: CECON .....................................................................................................444
Plugging Wells Back: WPLUG..................................................................................................................445
Workovers using WLIFT ...........................................................................................................................446
Well Testing: WTEST................................................................................................................................447
Cutting Wells Back: WCUTBACK............................................................................................................448
Group Control.................................................................................................................................................450
Creating a Group Hierarchy: GRUPTREE.................................................................................................452
Group / Field Production Control: GCONPROD ...........................................................................................454
Production Target Infringements................................................................................................................455
Solution Method.........................................................................................................................................456
Group Injection Control: GCONINJE ............................................................................................................458
Surface Injection Rate ................................................................................................................................459
Reservoir Volume Injection Rate ...............................................................................................................459
Re-injection................................................................................................................................................459
Voidage Replacement.................................................................................................................................459
Priority Control...............................................................................................................................................462
Group Economic Limits: GECON..................................................................................................................464
Convergence .......................................................................................................................................................467
Typical Convergence Problems......................................................................................................................468
Data Error...................................................................................................................................................469
PVT Table Errors .......................................................................................................................................469
VFP Table Errors .......................................................................................................................................470
Saturation Table Errors ..............................................................................................................................470
Typographic Errors ....................................................................................................................................471
Missing values............................................................................................................................................471
Special Characters......................................................................................................................................471
Model Design.............................................................................................................................................472
Grid Geometry............................................................................................................................................472
7. 6FKOXPEHUJHU
Eclipse 100 User Course Page 7 of 499 08/04/99
LGR Design................................................................................................................................................472
Program defects..........................................................................................................................................472
Eclipse 100 User Course Exercises.....................................................................................................................474
Exercise 1: Single Well Coning Model ..........................................................................................................475
Exercise 2: Sector Model RUNSPEC Section................................................................................................479
Exercise 3: Sector Model GRID Section ........................................................................................................481
Exercise 4: Sector Model PROPS and REGIONS Sections ...........................................................................485
Exercise 5: Sector Model Initialisation...........................................................................................................487
Exercise 6: Sector Model History Match........................................................................................................491
Exercise 7: Sector Model Recovery Optimisation..........................................................................................495
References...........................................................................................................................................................498
8. 6FKOXPEHUJHU
Eclipse 100 User Course Page 8 of 499 08/04/99
LIST OF FIGURES
Figure 1: ECLIPSE User Course Structure...........................................................................................................14
Figure 2: Material Balance Applied to Reservoir Simulation...............................................................................16
Figure 3: Reservoir Description versus Simulation Model ...................................................................................18
Figure 4: Role of Simulation.................................................................................................................................22
Figure 5: Role of ECLIPSE...................................................................................................................................24
Figure 6: ECLIPSE 100 and 200 Features ............................................................................................................26
Figure 7: Principal Simulator Activities................................................................................................................28
Figure 8: Simulation Grid Data Requirements......................................................................................................32
Figure 9: PVT and Rock Data Requirements........................................................................................................36
Figure 10: Initialisation Data Requirements .........................................................................................................38
Figure 11: Well flow rates and monthly averages as viewed using Schedule.......................................................42
Figure 12: Simplified Stages of a Full Field Simulation Study.............................................................................44
Figure 13: How to use the ECLIPSE documentation............................................................................................46
Figure 14: Relationship of Eclipse and pre-and post-processors ..........................................................................50
Figure 15: Eclipse outputs.....................................................................................................................................52
Figure 16: Available Eclipse output types ............................................................................................................56
Figure 17: Eclipse filenames for each output style part 1 .....................................................................................60
Figure 18: Eclipse filenames for each output style part 2 .....................................................................................62
Figure 19: Setting Personal File Extensions and Cases.........................................................................................63
Figure 20: Eclipse and related software file locations...........................................................................................64
Figure 21: Eclipse suite utility macros..................................................................................................................66
Figure 22: Major sections of the Eclipse input data file........................................................................................70
Figure 23: Summary of data file syntax................................................................................................................74
Figure 24: Syntax of Eclipse keywords.................................................................................................................76
Figure 25: Keywords for any section....................................................................................................................80
Figure 26: Minimum RUNSPEC options..............................................................................................................84
Figure 27: Eclipse 100 RUNSPEC keywords in alphabetical order .....................................................................88
Figure 28: Fast Restart File Structure ...................................................................................................................92
Figure 29: The console..........................................................................................................................................96
Figure 30: The vi device-independent editor ......................................................................................................100
Figure 31: Minimum GRID section contents......................................................................................................106
Figure 32: Grid data reading convention.............................................................................................................110
Figure 33: Radial data reading convention .........................................................................................................112
Figure 34: Block-centred and corner-point geometries.......................................................................................114
Figure 35: Sloping structure with fault represented in block centred geometry..................................................115
Figure 36: Sloping structure with fault represented in corner point geometry....................................................116
Figure 37: Example block-centred geometrical representation...........................................................................118
Figure 38: Example corner-point geometrical representation.............................................................................122
Figure 39: Grid cell property definition ..............................................................................................................124
Figure 40: Inputting grid data .............................................................................................................................126
Figure 41: Copying, Adding and Multiplying Data ............................................................................................130
Figure 42: Transmissibility conventions.............................................................................................................136
Figure 43: Cartesian grid transmissibility as viewed using GRAF .....................................................................138
Figure 44: OLDTRAN transmissibility definition ..............................................................................................139
Figure 45: Effect of uneven block sizes in BC geometry....................................................................................141
Figure 46: OLDTRANR transmissibility definition ...........................................................................................142
Figure 47: NEWTRAN transmissibility definition .............................................................................................144
Figure 48: Radial transmissibility .......................................................................................................................146
Figure 49: Shale representation...........................................................................................................................150
Figure 50: Modifying transmissibility using MULTX, FAULTS and MULTFLT.............................................154
Figure 51: Sources of non-neighbour connections..............................................................................................160
Figure 52: Fault non-neighbour connections.......................................................................................................162
Figure 53: Pinchout NNC generation..................................................................................................................164
Figure 54: LGR NNC generation........................................................................................................................166
Figure 55: NNC generation in dual porosity models...........................................................................................168
Figure 56: Aquifer non-neighbour connections ..................................................................................................170
Figure 57: Completing the circle in a radial model.............................................................................................172
9. 6FKOXPEHUJHU
Eclipse 100 User Course Page 9 of 499 08/04/99
Figure 58: Radial model geometry......................................................................................................................174
Figure 59: Grid Section Output Control..............................................................................................................178
Figure 60: Grid section keyword summary.........................................................................................................182
Figure 61: Purpose of the EDIT section..............................................................................................................190
Figure 62: EDIT section keyword summary.......................................................................................................192
Figure 63: Purpose of fluid property data ...........................................................................................................196
Figure 64: Generalised two-phase PVT envelope...............................................................................................198
Figure 65: Steps taken in black oil and compositional simulations ....................................................................202
Figure 66: Oil equation of state for the black oil model......................................................................................204
Figure 67: Dead oil PVT data entry using PVDO...............................................................................................208
Figure 68: Dead oil PVT data entry using PVCDO ............................................................................................210
Figure 69: Live oil PVT data entry with PVTO..................................................................................................212
Figure 70: Live oil PVT data entry with PVCO..................................................................................................214
Figure 71: Gas equation of state for the black oil model ....................................................................................216
Figure 72: Dry Gas Data Entry Using PVZG......................................................................................................220
Figure 73: Dry gas PVT using PVDG.................................................................................................................222
Figure 74: Wet gas PVT data using PVTG.........................................................................................................224
Figure 75: The water equation of state................................................................................................................226
Figure 76: Reference densities............................................................................................................................228
Figure 77: Black oil phase options......................................................................................................................230
Figure 78: Two oil types modelled using distinct PVT regions..........................................................................234
Figure 79: API tracking keywords and initial oil API.........................................................................................238
Figure 80: Rock compressibility.........................................................................................................................244
Figure 81: Required saturation function data for the PROPS section .................................................................248
Figure 82: Saturation function keyword families................................................................................................250
Figure 83: Default three-phase oil relative permeability calculation ..................................................................256
Figure 84: Significant saturation endpoints ........................................................................................................258
Figure 85: Effect of saturation scaling................................................................................................................260
Figure 86: Two-Point and Three-Point Endpoint Scaling...................................................................................263
Figure 87: SCALELIM keyword effect ..............................................................................................................264
Figure 88: Vertical saturation function scaling...................................................................................................266
Figure 89: Capillary pressure scaling..................................................................................................................270
Figure 90: PROPS section output control ...........................................................................................................274
Figure 91: Example REGIONS section data.......................................................................................................278
Figure 92: REGIONS Section Keywords............................................................................................................280
Figure 93: Function of the SOLUTION section..................................................................................................286
Figure 94: Block centre equilibration..................................................................................................................288
Figure 95: EQUIL keyword parameters..............................................................................................................292
Figure 96: Block Centre Equilibration................................................................................................................294
Figure 97: Level and Tilted Block Equilibration ................................................................................................296
Figure 98: Mobile Fluid Correction ....................................................................................................................300
Figure 99: Transition Zone Endpoint Variation..................................................................................................304
Figure 100: Matching Initial Water Distribution ................................................................................................306
Figure 101: Initial conditions defined by enumeration .......................................................................................308
Figure 102: Initial solution ratios........................................................................................................................310
Figure 103: History matching restart runs...........................................................................................................312
Figure 104: Multiple restarts during prediction ..................................................................................................314
Figure 105: Steps in creating a full restart run....................................................................................................315
Figure 106: Steps in creating a fast restart ..........................................................................................................316
Figure 107: SOLUTION section output control..................................................................................................320
Figure 108: Aquifer definition ............................................................................................................................324
Figure 109: Grid cell aquifer definition ..............................................................................................................326
Figure 110: Numerical aquifer definition............................................................................................................328
Figure 111: Model instability from poor aquifer design .....................................................................................330
Figure 112: Fetkovich aquifer definition ............................................................................................................332
Figure 113: Carter-Tracy aquifer definition........................................................................................................336
Figure 114: Flux aquifer definition.....................................................................................................................340
Figure 115: Output control..................................................................................................................................342
Figure 116: SUMMARY Section Purpose..........................................................................................................346
Figure 117: Additional SUMMARY mnemonic parameters ..............................................................................350
Figure 118: SUMMARY section output control keywords ................................................................................354
10. 6FKOXPEHUJHU
Eclipse 100 User Course Page 10 of 499 08/04/99
Figure 119: SCHEDULE section contents..........................................................................................................358
Figure 120: History matching and prediction regimes........................................................................................360
Figure 121: History match dataset structure........................................................................................................364
Figure 122: VFP curve specification...................................................................................................................368
Figure 123: VFP table usage in Eclipse ..............................................................................................................371
Figure 124: General well specification ...............................................................................................................374
Figure 125: Flow in gas wells .............................................................................................................................380
Figure 126: Specifying connections using COMPDAT......................................................................................384
Figure 127: Rescaling saturation tables at well connections: COMPRP.............................................................392
Figure 128: Partial completions in VE and diffuse flow models: COMPVE......................................................396
Figure 129: Historical rate specification using WCONHIST..............................................................................402
Figure 130: Setting injection rate using WCONINJE .........................................................................................406
Figure 131: Setting convergence criteria using TUNING and TUNINGL .........................................................410
Figure 132: Output control using RPTSCHED...................................................................................................414
Figure 133: Effect of zero gas re-solution rate DRSDT......................................................................................418
Figure 134: Simulation advance and termination................................................................................................420
Figure 135: Physical and Eclipse Models of Production Wells ..........................................................................422
Figure 136: Measures of Pressure in the Vicinity of a Well ...............................................................................425
Figure 137:A selection of manual workover keywords ......................................................................................426
Figure 138: Structure of the SCHEDULE section in prediction mode ...............................................................432
Figure 139: The WCONPROD keyword ............................................................................................................436
Figure 140: Example of the effect of WCONPROD...........................................................................................438
Figure 141: Application of economic limits........................................................................................................440
Figure 142: Actions taken on violating economic limits.....................................................................................441
Figure 143: A selection of automatic workover keywords..................................................................................442
Figure 144: The WECON keyword ....................................................................................................................443
Figure 145: The CECON keyword......................................................................................................................444
Figure 146: Plugback using WPLUG..................................................................................................................445
Figure 147: The WLIFT keyword for retubing wells..........................................................................................446
Figure 148: The WTEST keyword for well testing.............................................................................................447
Figure 149: The WCUTBACK keyword ............................................................................................................448
Figure 150: Controlling production for a group of wells ....................................................................................450
Figure 151: The GRUPTREE keyword ..............................................................................................................452
Figure 152: The GCONPROD keyword .............................................................................................................454
Figure 153: The GCONINJE keyword................................................................................................................458
Figure 154: Priority control keywords ................................................................................................................462
Figure 155: The GECON keyword .....................................................................................................................464
Figure 156: A typical convergence problem report.............................................................................................468
Figure 157: Typical causes of convergence problems ........................................................................................469
Figure 158: Single Well Coning Model..............................................................................................................475
Figure 159: Model dimensions............................................................................................................................479
Figure 160: Basic model layer data.....................................................................................................................481
Figure 161: XZ model section at Y=0.................................................................................................................483
Figure 162: YZ model section at X=0.................................................................................................................484
Figure 163: Sector Model PROPS Section Construction....................................................................................485
Figure 164: Sector Model Initialisation ..............................................................................................................487
Figure 165: Sector Model History Matching ......................................................................................................491
Figure 166: Sector Model Recovery Optimisation..............................................................................................495
11. 6FKOXPEHUJHU
Eclipse 100 User Course Page 11 of 499 08/04/99
LIST OF EXERCISES
Exercise 1: Single Well Coning Model...............................................................................................................475
Exercise 2: Sector Model RUNSPEC Section ....................................................................................................479
Exercise 3: Sector Model GRID Section.............................................................................................................481
Exercise 4: Sector Model PROPS and REGIONS Sections................................................................................485
Exercise 5: Sector Model Initialisation...............................................................................................................487
Exercise 6: Sector Model History Match ............................................................................................................491
Exercise 7: Sector Model Recovery Optimisation ..............................................................................................495
14. 6FKOXPEHUJHU
Eclipse 100 User Course Page 14 of 499 08/04/99
Purpose
Figure 1: ECLIPSE User Course Structure
The ECLIPSE 100 USER COURSE is intended to acquaint delegates with the construction
of simulation models using the features that are common to all installations of ECLIPSE.
As such it takes the structure of a guided tour of the input data and incorporates
discussion of the most common ECLIPSE keywords and facilities. ECLIPSE contains a
number of additional features that are discussed in advanced user courses, which
supplement this course. Also, this course does not specifically address the methodology
of reservoir simulation, engineering data preparation and analysis or conduct of
simulation studies. For information on GEOQUEST courses on these and other aspects of
reservoir simulation and engineering, please approach your course trainer or contact
your local Training Administrator.
Build and execute simulation
models using basic Eclipse
facilities
Introduction to simulation and
the Eclipse software family
File naming conventions and
structure
Data file syntax
Principal Eclipse keywords
History matching
Prediction
Discuss one section of the
data file at a time
Build a model from scratch
Eclipse 100 User Course
15. 6FKOXPEHUJHU
Eclipse 100 User Course Page 15 of 499 08/04/99
Purpose
During this course you will become acquainted with the basic features and keywords of
the ECLIPSE black oil simulator. An overview of the input data and file handling
characteristics is followed by lectures on each section of the input data. Each is
followed by a practical exercise. Taken together the exercises consist of construction of
a simulation model from scratch followed by matching the simulated past production to
the measured production, and future recovery optimisation by simulation of a number of
production scenarios. The course incorporates tuition in the use of the GRAF post-
processor as an integral part and the relationship between ECLIPSE and the other pre-
and post-processors in the GEOQUEST Simulation Software suite is also explained.
16. 6FKOXPEHUJHU
Eclipse 100 User Course Page 16 of 499 08/04/99
What is Reservoir Simulation
Figure 2: Material Balance Applied to Reservoir Simulation
• The simplest simulation is a material balance model
• Material balance models use averaged quantities and ignore spatial variation and
anisotropy
• The reservoir simulator is discrete, finite difference, representation of a continuous
system
• It takes into account the variation of fluid and rock properties in space i.e. space
discretisation.
• The simulator advances temporally in discrete steps and can be interrogated at any
time i.e. time discretisation.
• It is a good reservoir engineering tool, but requires good engineering judgement
• It can be used to solve problems that cannot be solved in any other way because it is
numerical, not analytical.
Mass in - Mass out = Accumulation
or
Flow in - Flow out = Rate of accumulation
Material
Balance
Model
Reservoir
Simulation
Model
17. 6FKOXPEHUJHU
Eclipse 100 User Course Page 17 of 499 08/04/99
What is Reservoir Simulation
Reservoir Simulation, like material balance calculation, is a form of numerical
modelling which is used to quantify and interpret physical phenomena with the ability
to extend these to project future performance. Material balance has the limiting
characteristics of:
• No account of spatial variation (so-called “zero-dimensional”)
• Reservoir and fluid properties as well as fluid flows are averaged over the entire
reservoir
• To examine the system at a number of discrete points in time requires a material
balance calculation over each time interval.
Reservoir simulation, on the other hand, divides the reservoir into a number of discrete
units in three dimensions and models the progression of reservoir and fluid properties
through space and time in a series of discrete steps. As in material balance, the total
mass of the system is conserved. It can be thought of as equivalent to a coupled system
of material balance models. This can provide the engineer with far more insight into
recovery mechanisms. History matching may even make the engineer aware of missing
information. Ultimately, a simulator is only a tool and needs good engineering
judgement in order to obtain useful results.
18. 6FKOXPEHUJHU
Eclipse 100 User Course Page 18 of 499 08/04/99
How Does the Model Relate to the Reservoir
Figure 3: Reservoir Description versus Simulation Model
• The model is not identical to the reservoir
• Model performance depends on data quality and quantity
• The model reflects the reservoir behaviour if the reservoir is accurately represented
• Some phenomena may be unknown or have to be approximated
• Data must be validated, i.e. history matched.
• Data modifications must be physically viable and justified
• The model contains artefacts which are functions of the model construction
19. 6FKOXPEHUJHU
Eclipse 100 User Course Page 19 of 499 08/04/99
How Does the Model Relate to the Reservoir
The reservoir and its simulation differ because of the following factors:
• Input data is uncertain. A measurement of any kind has an associated uncertainty.
For instance, permeability estimates based on core flooding will yield a range of
values centred on an average. Deciding whether the available measurements are
adequate to calculate an average permeability, and which of the measurements
really do represent the permeability the engineer requires is an essential task. One of
the largest parts of a simulation study consists of gathering the available data and
judging the reliability and relevance of every part of it. This is often much more
time consuming than constructing a simulation model. If the model is to behave in
the same way as the reservoir, then the input data must accurately represent the
reservoir characteristics it is intended to describe although the simulation model
does not necessarily bear a superficial resemblance to the reservoir, as in Figure 3.
• Reservoir processes and characteristics may be unknown. Well data provides
information within the well drainage region plus some general information on the
reservoir characteristics beyond that region. Seismic data provides additional
structural detail. Beyond this geological information is either inferred or
extrapolated. The left hand diagram of Figure 3, for instance, is a highly detailed
interpretation but the presence and locations of the various channel sands could only
be confirmed by drilling.
• The simulation software may be unsuited to modelling certain processes. Simulation
models are all discrete numerical approximations to continuous systems. The
diffusivity equation on which simulation is based is a non-linear partial differential
equation which simulators can only solve directly for the very simplest of models.
Instead, approximations in the form of linear difference equations are solved. For
instance, the difference equations do not apply to highly compressible fluids and so
are unsuited to modelling the detailed dynamics of free gas flow at intermediate to
high pressures, typically from approximately 3500 psia. This is usually only
relevant for flow into wells from the grid cells they are connected to, in which case
a choice of inflow equations is provided.
• The simulation model introduces artefacts that alter the model performance. All
simulators model the reservoir and wells as a collection of points acting as sources,
sinks and receptacles of fluids. These points represent large and complex objects, so
20. 6FKOXPEHUJHU
Eclipse 100 User Course Page 20 of 499 08/04/99
the way in which reservoir properties are averaged to create the properties at
discrete points is bound to alter the model performance. For instance, a single
simulation grid cell may be at a depth of 3Km, 100m * 100m * 10m, have a single
value of porosity, three permeabilities in X, Y and Z, a net-to-gross plus a set of
relative permeability and capillary pressure curves. This cell is treated as a single
point by the simulator. Fluid will only flow through that cell in the simulation in the
same way as in the reservoir rock if all the above properties have been averaged
and/or scaled up such that the flow characteristics are preserved. The procedure for
doing this is known as upscaling and is essentially a means of countering errors
introduced by discretising the reservoir.
22. 6FKOXPEHUJHU
Eclipse 100 User Course Page 22 of 499 08/04/99
Why Reservoir Simulation?
Figure 4: Role of Simulation
• It can be used to quickly and cheaply assess various production scenarios
• It can accurately model real geological structure and petrophysics
• It can model a wide range of recovery techniques
• Recognised by banks and funding organisations as supporting evidence for
investment decisions
• In many parts of the world, it is a statutory requirement
Reservoir
Simulation
Quick and cheap assessment of
production scenarios
Wide range of recovery techniques
Required by law in many countries
Recognised by banks and funding
bodies
Accurate geology and petrophysics
23. 6FKOXPEHUJHU
Eclipse 100 User Course Page 23 of 499 08/04/99
Why Reservoir Simulation?
Typical uses of Reservoir simulation include
• Accurate determination of recoverable reserves
• Prediction of production profiles
• Determination of the number of wells needed
• Determination of the best perforation policy
• Determination of the best well pattern
• Assessment of the effects of early gas or water breakthrough and investigation of
how to minimise them
• Estimation of the size of separation facilities and when they may be needed
• Determination of optimum injection rates and the best time for injection
• Confirm understanding of reservoir flow barriers to assess whether undrained
regions exist
• Estimate storage capacities and production rates from underground gas storage
facilities
• Estimation of optimal means of meeting gas deliverability contracts
• Estimation of financial risk by economic analysis of best, worst and most likely
scenarios.
24. 6FKOXPEHUJHU
Eclipse 100 User Course Page 24 of 499 08/04/99
Why ECLIPSE?
Figure 5: Role of ECLIPSE
• Used by almost all oil companies and many government agencies. In certain parts of
the world, it has to be ECLIPSE. Over 300 installations worldwide.
• Tested and proven to be robust and reliable since it was launch at SPE San
Francisco 1983. Supported on many platforms
• Extensive features modelling almost every development scenario plus specialised
add-on features (ECLIPSE 200).
• Nany ancillary packages to facilitate data preparation and processing of results:
VFPI, PSEUDO, and GRAF. Additionally, there are GRID, SCAL, SCHEDULE,
PVTI, and RTVIEW. There are support teams in many parts of the world to provide
user help.
• There is a dedicated team of developers working on ECLIPSE. Development
continues on the basis of industrial need.
Eclipse
The
"standard"
black oil
simulator
Can model
almost any
reservoir
situation
Reliable,
accurate,
easy to use
Integrated
with
geological
and mapping
packages
Extensive
support
services
Strong
product
development
25. 6FKOXPEHUJHU
Eclipse 100 User Course Page 25 of 499 08/04/99
Why ECLIPSE?
ECLIPSE originated from ECL in the late 1970’s. At the time ECL specialised in seismic
data acquisition and quality control, and it became apparent that diversification into
dynamic flow modelling would be advantageous. Although a number of reservoir
simulators were available at the time, the most popular commercial simulators were not
fully implicit and did not use fully implicit well models. The team of reservoir
engineers and software developers chosen by ECL was particularly well placed to create
a new product having these features, since most of them were very well versed with the
PORES simulator. The first commercial release of the new simulator, ECLIPSE, was
announced in 1983 SPE. ECLIPSE rapidly became the simulator of choice in Europe and
still is today, although the ownership of the technology has changed a number of times
since the first release. At present there are in excess of 300 installations worldwide.
26. 6FKOXPEHUJHU
Eclipse 100 User Course Page 26 of 499 08/04/99
ECLIPSE Features
Figure 6: ECLIPSE 100 and 200 Features
• The basic features are known as ECLIPSE 100
• ECLIPSE 100 features are available on all ECLIPSE installations
• Additional features are collectively known as ECLIPSE 200
• ECLIPSE 200 features are part of the ECLIPSE program
• ECLIPSE 200 features are activated by special passwords. No re-installation is
needed to acquire extra ECLIPSE 200 features.
• ECLIPSE 100 and ECLIPSE 200 are usually referred to collectively as ECLIPSE.
Basic Features ("Eclipse 100")
Free format input
1, 2 or 3-phase simulation
Directional Kr
Endpoint Scaling
CP / BC Geometry
Non-Neighbour Connections
Analytical and Numeric Aquifers
Dual Porosity, Dual Permeability
Pc & Kr Hysteresis
Vertical Equilibrium
Mobile Fluid Correction
Fine Grid Equilibration
Molecular Diffusion
API & Tracer Tracking
Vertical, Horizontal & Deviated
Wells
Crossflow & Commingling in Wells
Extensive Surface Facility Modelling
Automatic Drill Queue & Workover
IMPES & Implicit Formulations
Extensions ("Eclipse 200")
Local Grid Refinement & Coarsening
Wellbore Friction
Multi-Segment Wells
Flux Boundary Option
Surface Networks
Gas Lift Optimisation
Gas Field Operations
Polymer Flood
Environmental Tracers
Solvent Model
Polymer Injection
Foam Injection
Reservoir Coupling
Coal Bed Methane Option
Parallel LGRs
Shared Memory Parallel Option
GI Pseudo-Compositional Model
27. 6FKOXPEHUJHU
Eclipse 100 User Course Page 27 of 499 08/04/99
ECLIPSE Features
The basic ECLIPSE options available in all installations are often known as ECLIPSE 100
Additional features purchased separately are known as ECLIPSE 200
ECLIPSE 100 is a fully implicit, three-phase, three-dimensional, general-purpose black
oil simulator.
Included in the ECLIPSE 100 package are a number of pre- and post-processing and help
utilities:
• GRAF 2D graphics display package
• EDIT syntax sensitive editor specially designed for ECLIPSE data preparation
• PSEUDO 3D pseudo function generator
• VFPI well bore hydraulics pre-processor
• FILL corner point geometry pre-processor
• Online help in FrameMaker® format
There are also a large number of optional extensions to ECLIPSE 100 to model special
reservoir situations. These are collectively known as ECLIPSE 200. All and more of the
features listed in Figure 6 are contained in one program but only the basic features are
available to all users. The additional features are purchased separately and activated
together with the basic facilities by special passwords issued by GEOQUEST. No
reinstallation of ECLIPSE is necessary to activate additional features.
The software is supported on most computers with an ANSI standard FORTRAN77
compiler and a minimum of 8MB memory, including UNIX workstations (e.g. IBM
RS6000, Sun SPARC station and Silicon Graphics), mainframes (e.g. Convex and
Cray) and PCs (386 and Pentium).
28. 6FKOXPEHUJHU
Eclipse 100 User Course Page 28 of 499 08/04/99
How ECLIPSE Works
Figure 7: Principal Simulator Activities
Static Reservoir Description
• Construct a geometrical model of the reservoir in discrete grid blocks or cells
• For each grid block, supply dimensions, elevation, porosity, permeability
PVT and Rock data
• Supply fluid formation volume factors, viscosities, densities, gas-oil/oil-gas ratios,
rock and water compressibilities
• Supply phase relative permeabilities, interface capillary pressures.
Initialisation data
• Provide fluid contacts, reference depth and pressure and capillary pressures
Well data
• Provide well and completion locations, Production/injection rates of wells and
groups and other data such as skin factors, well radius, well controls, etc.
GRID, EDIT
Sections
Calculate Pore
Volumes,
Transmissibilities,
Depths and NNCs.
PROPS, REGIONS,
SOLUTION Sections
Initialise, calculate
initial saturations,
pressures and fluids
in place
Kr
Sw
FVF,µ
P
SCHEDULE Section
Define wells and
surface facilities.
Advance through
time by material
balance for each
cell with wells as
sinks or sources
FlowRate
Time
OWC
GOC
29. 6FKOXPEHUJHU
Eclipse 100 User Course Page 29 of 499 08/04/99
How ECLIPSE Works
• ECLIPSE is a batch program. The engineer creates a single input data file for
ECLIPSE. This data file contains a complete description of the model. The model
consists of reservoir description, fluid and rock property description, initial
conditions, wells and their phase flow rates and surface facilities. The input file is a
text file containing a collection of keywords and comments. Each keyword has a
specific syntax although many keywords have similar or identical syntax. The data
file is divided into sections by a few specific keywords. Each section has a
particular purpose. In general, ECLIPSE keywords are usable only in certain sections
of the data file. ECLIPSE is invoked and the simulation is performed with minimal
interaction from the user.
• ECLIPSE reads the input data file section by section and processes each section in
turn once that section has been read. Various data and consistency checks are made
before proceeding to the next section. The last section is exceptional because it
specifies time-dependent data and is not read and processed as a whole; the
keywords are processed in the order they are read from the data file.
• The first task performed by ECLIPSE is to allocate memory for the input data.
Although ECLIPSE is dynamically dimensioned and reserves as much memory as
required for the simulation as a whole, different kinds of information in the
simulation require varying amounts of memory.
• The simulation grid geometry and properties are processed into a form more
convenient for calculation of flows. For each cell, ECLIPSE calculates the pore
volume, transmissibility in three dimensions and cell centre depth and creates
connections to other cells to/from which fluids may flow. These quantities may be
modified either by the user or by ECLIPSE.
• The rock and fluid properties are specified next. The term fluid properties refers to a
set of input tables that effectively define the phase behaviour of for each flowing
phase. The term rock properties refers to sets of input tables of relative permeability
and capillary pressure versus saturation. Effectively, this defines the connate (or
irreducible) , critical and maximum saturation of each phase, supplies information
for defining the transition zone and defines the conditions of flow of phases relative
to one another. This strongly affects the ratios of produced phases, i.e. water cuts
and GORs.
30. 6FKOXPEHUJHU
Eclipse 100 User Course Page 30 of 499 08/04/99
• Next, the initial conditions are defined, often by specifying the OWC and/or GOC
depths and the pressure at a known depth. ECLIPSE uses this information in
conjunction with much of the information from previous stages to calculate the
initial hydrostatic pressure gradients in each zone of the reservoir and allocate the
initial saturation of each phase in every grid cell prior to production and injection.
This is called initialisation.
• The final section of the data file is where simulation actually begins. Wells are
drilled, perforated and completed, production and injection targets are set up, wells
are opened and fluids flow through the reservoir, driven by the wells.
• ECLIPSE outputs various information on the simulation results and its progress at
dates during the simulation, defined by the user. Once the run has finished, the
output is examined using text editors and post-processors of various degrees of
sophistication.
32. 6FKOXPEHUJHU
Eclipse 100 User Course Page 32 of 499 08/04/99
Static Reservoir Description
Figure 8: Simulation Grid Data Requirements
• Select model geometry
• Design areal grid
• Design layering structure
• Define cell properties
• Define region properties
33. 6FKOXPEHUJHU
Eclipse 100 User Course Page 33 of 499 08/04/99
Static Reservoir Description
The type of model geometry depends on a number of factors including:
• Extent of the area to be modelled
• Level of detail required in the study
• Level of detail of available data
• Complexity of faulting structure
• Formation contiguity across faults
• Presence of sloping and/or listric (slump) faults
• Time available for model construction
Available geometrical options are block-centred and corner point. Each may be radial or
Cartesian. The essential features are:
• Block-centred geometry uses cells with vertical sides, horizontal upper and lower
surfaces. The cells are parallelepipeds i.e. each cell has a single height, width, depth
and elevation.
• Corner point geometry defines cells by the locations of their corners. Corner point
cells may be skewed, tilted, wedge-shaped or pinched-out altogether.
A model must be either corner point or block-centred. The two cannot be mixed.
A model must be either radial or Cartesian but it may contain Local Grid Refinements
(LGRs) of different geometry.
Having chosen the character of the geometry, the first stage of simulation grid design is
usually to create an areal grid. The features of the areal grid are usually
• Based on the top structure map
• Contains only one layer
• Wells are at the centres of grid cells where possible
• Faults are at the edges of grid cells where possible
• No-flow boundaries are observed
• Size and shape of cells varies:-
• Cells are often distorted to honour fault traces
• Cells are often smaller in the vicinity of wells
• Cells may be larger in the aquifer
The design of the vertical layering usually follows. This depends on:
34. 6FKOXPEHUJHU
Eclipse 100 User Course Page 34 of 499 08/04/99
• Available horizon data
• How members and/or formations are combined into simulation grid layers
• The permeability variation with depth
• The extent and effectiveness of barriers to vertical communication such as shales
Once the geometry is in place the cell properties have to be defined. This includes, but
is not restricted to, porosity, permeability in three dimensions and net to gross. This
may originate from various sources such as:
• Measured values at wells extrapolated over the entire field
• Correlations to known quantities
• Analogy with neighbouring fields
• Geostatistical property modelling
After that stage the reservoir is usually subdivided into distinct regions for various
purposes such as:
• Reporting flows and fluids in place e.g. for formations separated by shales
• Specifying regions of distinct fluid contacts e.g. in isolated fault blocks
• Specifying regions in which fluids have different PVT properties e.g. oils of
different API.
• Specifying regions in which rock properties are distinct e.g. connate or irreducible
water saturation.
36. 6FKOXPEHUJHU
Eclipse 100 User Course Page 36 of 499 08/04/99
PVT and Rock Data
Figure 9: PVT and Rock Data Requirements
PVT Data
• Derived from PVT analyses and supplied as tables of properties versus pressure
• Phase Formation volume factors Bo, Bg, Bw as appropriate
• Phase viscosities µo, µg, µw as appropriate
• Gas-oil Ratio Rs and / or Oil-Gas Ratio Rv
• The PVT data can vary across the reservoir
• Needed to set initial pressure gradients and component distributions
Rock Data
• Derived from SCAL analysis, supplied as tables of properties versus saturation.
• There can be several different curves for various sections of the reservoir
• Needed to set maximum, minimum and critical phase saturation in each zone
• Required to define and define transition zone saturations
37. 6FKOXPEHUJHU
Eclipse 100 User Course Page 37 of 499 08/04/99
PVT and Rock Data
PVT data are the results of laboratory analysis of reservoir fluids. This data is required
to: -
• Describe the phase behaviour of reservoir fluids at all times
• Calculate the density of each phase, which is in turn used
• to set up the initial conditions of the simulation
• calculate the mass of each phase in each grid block for material balance purposes
The fluid PVT properties can vary with depth and/or areally as well as being different in
distinct regions of the reservoir.
Rock data are the results of special core analysis experiments. This data is required to: -
• Set the maximum and minimum saturations of each flowing phase, which in turn is
used to define equilibrium phase saturations
• Define the transition zone extent and properties
• Describe the flow behaviour of distinct fluids in order that phase flows between grid
blocks can be calculated.
38. 6FKOXPEHUJHU
Eclipse 100 User Course Page 38 of 499 08/04/99
Initialisation Data
Figure 10: Initialisation Data Requirements
• Where equilibration is used the initial saturation distribution and pressure at a datum
depth are derived from well testing, well logs, RFT and PLT measurements
• Where enumeration is used the initial conditions are derived from maps or other
distributions of pressure and saturation.
• There may be several different equilibration regions
Pressure
Depth
GOC
OWC
Free Water Level
Datum