A guide to how and where to use Flowmaster Electromechanical Components.

1. Modeling Mechanical System Interactions in Flowmaster
Automotive Fuel Injection and Aircraft Hydraulics
Actuation System Examples
Sudhi Uppuluri
Shayne Ziegler Arlie Nuetzel
Computational Sciences
Flowmaster USA Flowmaster USA
Expert Group
USA Call-in Number: 1-631-267-4890
Click “Global Call-in numbers for other regions
Access Code: 958 533 404

2. Agenda
• Overview of Flowmaster
• Introduction to Electro-Mechanical Components
• Case Study: Aircraft Hydraulic Actuation System
• Case Study: Gasoline Fuel Injection System
• Question & Answer Session
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3. Flowmaster Overview - Analysis Capabilities
• Incompressible and compressible analysis
• Water, Oil, Fuel, compressible air, natural gas, etc…
• Mach Number / choking considerations for compressible
• Steady state scenarios
• Snapshot results for given system conditions
• Transient scenarios
• Time changing results in response to varying conditions.
• Examples:
• Aircraft flight profile (long transient)
• Valve/ pump shutdown - Fluid Inertia Considerations (fast transient)
• Bleed air pneumatics and boundary condition varying transients.
• Thermal Transient
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4. Flowmaster Overview - Analysis Capabilities
• Heat transfer
• Pipe Heat Transfer
• Heat Exchanger
• Solids Components: Complex or Conjugate Heat Transfer (Convection,
radiation, conduction)
• Thermal analysis throughout the system.
• Design Options
• Sizing Flow Balancing
• Parametric Analysis
• Built – in Features
• COM Automation with Excel
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5. Flowmaster Overview - Analysis Capabilities
• Aerospace
• Gas / Liquid Interface Tanks for Propulsion
• Body Forces Analysis for Fuel Systems
• ECS Pack Components and Humidity
• Automotive
• Under hood Airflows / Segmented Analysis
• Lubrication Bearing Models
• AC Systems / Cabin Comfort Model
• Gas Turbine
• Secondary Flows: Swirl Solver, Cavity Analysis, Radial, Axial, and Tangential
flow vectors
• Combustion: Conjugate Heat Transfer and Equilibrium Heat Release (custom)
• Oil and Gas
• GIS Data Import
• Pipeline Profile (Excel Data / Pods) Import.
• Pipeline Results Analyzer
• Buried and Partially Buried Pipe Heat Transfer Options
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6. Flowmaster In Aerospace
Where Can Flowmaster Be Used In Aerospace?
• ECS Systems
• Bleed Air Systems
• Ice Protection Systems
• Fuel Systems
• Hydraulic Systems
• Potable Water Systems
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7. Aerospace Fuel System Example
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8. Flowmaster In Automotive
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9. Automotive Cooling Example
Cooling System
Cabin airside
Under hood Airflow
Drive Cycles
Lubrication
System
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10. Introduction to Electro-Mechanical Components

11. Introduction to Electromechanical
Components
Damper Spring End Stop Port
Force Solenoid Mass Earth
Lever Lever Spacer Friction
Piston: Piston: Compressible
Double Single Cylinder
Acting Acting 2011© Flowmaster Group
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12. Introduction to Electromechanical
Components
DCV: DCV: DCV: DCV:
2 port 3 Port 4 Port 4 Port
Hydraulic Hybrid Elastic Pipe
PD Pump
Motor Pump (MOC)
Cylinder: Cylinder: Cylinder: Volume
1R1A 1R2A 2R2A
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13. Introduction to Electromechanical
Components
Mechanical - Fluid Interaction Modeling
• Spool Valve
• Fuel Injector Valve
Reference: virtual.cvut.cz/dynlab/courseModeling/node43.html
Reference: www.answers.com/topic/fuel-injection
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14. Introduction to Electromechanical
Components: Fluid Transients
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15. Introduction to Electromechanical
Components: Fluid Transients
Pressure waves travel through the pipe at the speed of sound. The passage of these
waves is calculated using the Method of Characteristics, assuming a constant wave
speed. Pressure in the system is directly related to velocity (flow rate).
In transient events flow rate changes cause pressure fluctuations (and vice versa). For
rapid transient events the pressure rise is:
∆P = a * ρ* ∆v
Where:
∆P = Pressure change in fluid
ρ = Liquid density
∆v = Velocity change
1
a = Wave speed 
1 d 
  
k tE 
‘Fluid Transients in Systems', Wylie & Streeter, Published by Prentice Hall 1993, ISBN 0-13- 322173 -3.
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16. Investigation: Pressure Surge Transient Analysis
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17. Investigation: Pressure Surge Transient Analysis
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18. Introduction to Electromechanical
Components
Force
End Stop
Earth
Port
Spring
Damper
Mass
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19. Introduction to Electromechanical
Components
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20. Aerospace Applications of Mechanical Components
Arlie Nuetzel
Applications Engineer
Flowmaster USA, Inc

21. Mechanical System Challenges
• System Sizing
• Pump Capacity
• Pressure Requirements
• System Volume
• Hydraulic Power vs. Speed
• Packaging
• Survivability
• Failure Modes
• Redundancy
• System Interactions
• Resonance
• Cavitation
• Controller Oscillation
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22. Standard PD Pump Component
• Hydraulic PD pump
• Pseudo-transient, time averaged output
Pressure Gauge
Speed Controller
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23. PD Pump Output Results
Pressure Gauge
Speed Controller
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24. Developing a Mechanical PD Pump Model
• Piston Based
• Equation of Motion:
• Controller Script:
• Inlet/Outlet Valves
• Simple Check Behavior
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25. PD Pump Model Performance
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26. Three Piston PD Pump
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27. Transient Results
• fd
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28. RPM sweep to find resonance
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30. FFT
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31. Hydraulic System Modeling
• Pump
• Flap Actuator
• Slats Actuator
• Landing Gear
• Door Actuator
• Gear Actuator
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32. Flap/Slat Actuator
• Directional Control Valve
• Flow Restrictor
• Hydraulic Motor
• Jack Screw (controller)
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33. Landing Gear Actuator
• Directional Control Valve
• Flow Restrictor
• Hydraulic Piston
• Mechanicals
• Mass
• End Stop
• Earth
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34. Control Surface positions
• Master Controller
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36. Custom Display
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38. Fuel Injector Dynamics Modeling
Sudhi Uppuluri
Principal Investigator
Computational Sciences Experts Group
(781) 640-2329

39. Fuel Injector Dynamics Modeling
Sudhi Uppuluri, Principal Investigator
Computational Sciences Experts Group, LLC
(www.cseg.us)

40. WE ARE CSEG
We don’t sell software. We bring our modeling expertise
and make your CAE software do
advanced stuff.
The stuff you bought the
software to do to begin with.

41. Where CSEG fits in
Augment your team with
expert simulation
capability
Your
Design • Deep expertise on
Team CSEG system modeling
• Brings best-in-class
tools to the table
• Added resource to your
design team
Don’t just buy software. Add simulation capability to your team.

42. A smart approach to simulation
Traditional approach CSEG approach
• Evaluate which software to buy • CSEG does the analysis and provides
with a trial license you with a simulation answers
• Purchase software tool quickly(CSEG bring the right tools
and manpower to the table)
• Schedule and pay for training
• Go through the learning curve of • Choose the right software once the
the tool while building the model analysis is done (CSEG provides the
• Spend ~2-3 yrs gaining models)
competence and confidence on
modeling with the new tool
 Very cost-effective
 Expensive approach  Have simulation answers quickly (with
 Lost opportunity costs confidence in them)
 Simulation tool not effective during  Meet your analysis deadlines
the initial period  Significantly shorten the learning
 Software training does not cover your curve
application.  Get calibrated model of your system
built by experts immediately.

43. Our Approach
• We focus on the problem, combining the right
tools to provide accurate answers for your simulation
challenge – not the tool any one company is selling. CSEG
maintains licenses for best in class COTS tools providing instant
technical capability expansion to your projects.
System Tools CFD Tools
• Flowmaster* • Ansys Fluent
• Amesim • STAR-CD
• Gamma Technologies
Other
Optimization Tools • Matlab/Simulink
• iSight* • Can integrate your
• ModeFrontier in-house software
with COTS

44. Gasoline Direct Injection
• Simplified
Example of
electronically
controlled gasoline
direct injection
system
* Example layout from Wikipedia, retrieved Oct 2011

45. The system model
Engine Control Unit
(Simulink)
Cylinder firing Fuel
Timing, Voltages consumption
 Integrate with
engine control to
evaluate and
optimize fuel
consumption
 Precise engine-
management
software to
accurately tailor
fuel-injection
timing and
duration

46. 1D translation of the injector
* Reference from
Advanced Engine
Technology, Heinz
Heisler

47. Modeling Considerations
(Mechanical)
Coefficient of
restitution to
model needle
bouncing

48. Modeling Considerations
(Fluid)
Pressure
waves inside
the passages
Combustion
chamber
pressure Cd
Discharge
Coefficient

49. Injector Dynamics
1
2
3
 Flow rate fluctuations from
1
supply pressure variations
2 Needle bouncing

 Pressure waves from needle
3
closure

50. Overall Network

51. Which variables should I really spend a lot of
time getting right ?
What about:
supply pressure fluctuations?
Coefficient of Discharge?
Needle mass?

52. Parameter study
• Sensitivity study of select
input parameters
performed using Isight by
Simulia.
• Isight linked with
Flowmaster through MS
Excel
• Automated input
generation, runs and
results extraction

53. Parameter Study
(an example)
 Shows effect of select variables on
amount of fuel injected
 Extremely Important that we get the
needle port area, Cd and fluctuations in
the supply pressure accurately
characterized.
 Variables such as Coefficient of
Restitution, and fuel filter loss were not
that important in this case.
* Analysis using Isight by Simulia

54. Parameter Study
(an example)
Fluctuations in mass of fuel
injected
Fluctuations in input
parameters
* Analysis using Isight by Simulia

55. Calculating Cd
• Discharge coefficient directly affects the fuel flow rate
through the injector.
• Cd is typically a function of injector port area.
• Few ways of determining Cd
– Literature indicates Cd range from 0.690.73 (references
avbl) with some examples much higher.
– CFD is a good way to determine the Cd for your particular
injector (at varying port openings) (predictive)
– Can back-calculate from available test data (non-predictive)

56. FURTHER Sudhi Uppuluri has over 14 years of
experience in the simulation industry. He
DISCUSSION
worked as a consulting engineer and sales
manager at Flowmaster USA for 8 years
.He has various technical publications on
related subjects in SAE and AIAA journals.
He holds a Masters in Aerospace
Engineering from the University of Illinois
at Urbana-Champaign and a Certificate
in Strategy and Innovation from the MIT
Sloan School of business.
Contact:
Sudhi Uppuluri
Principal Investigator
Sudhi.uppuluri@cseg.us
(781) 640 2329
www.cseg.us

57. Question & Answer Session
Thank you for attending!
Please use the “Raise hand” icon to ask technical questions...
For additional information, please contact…
Flowmaster Sales inquires: Flowmaster Support inquires:
Us-sales@flowmaster.com Us-support@flowmaster.com
847-901-4224 847-901-4242
Sudhi Uppuluri
Principal Investigator
Computational Sciences Experts Group
(781) 640-2329
2011© Flowmaster Group
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