Ähnlich wie Computer Modeling of Air Flow and Contaminant Transport in Environments and Electrophotographic Machines (Goodarz Ahmadi and Fa-Gung Fan) (10)
2. CAMP
Clarkson University
• Environmental Applications
• Environmental Applications
- Respiratory Deposition
- Respiratory Deposition
- Aerodynamic Lenses
- Aerodynamic Lenses
- Airflow near and in Buildings
- Airflow near and in Buildings
- Airflow and pollutant near Bridges
- Airflow and pollutant near Bridges
• EHD in Corona Devices
• EHD in Corona Devices
- Electrostatic Separator
- Electrostatic Separator
- Corotron Devices
- Corotron Devices
3. CAMP
Clarkson University
• particle and fiber deposition
Hopke-NIOSH
Hopke-NIOSH
in human lung and nose
4. CAMP
Clarkson University
• Particle and fiber deposition in human lung
0.95cm FLUENT
45o
3.01cm
2.78cm 30o
U=3m/s 45o
1.46cm
2cm
1.5cm
7.2cm
Schematic of the triple
Grid schematic
bifurcation airway
5. CAMP
Clarkson University
Velocity vector plot Particle Deposition
6. CAMP
Clarkson University
80
50
70 Experimental Data Third Bifurcation
40
(%)
60 Second Bifurcation
50 30
Numerical Simulation First Bifurcation
40 20
30
10
20
0
10 10-2 10-1 100
100 101
Particle Diameter (µm)
st
Comparison of total deposition with Variations of the capture efficiency
the experimental data of Hinds (1982) with particle Stokes number
7. CAMP
Clarkson University
η (%)
Li and Ahmadi (1996)
Velocity magnitude
contours
8. CAMP
Clarkson University
Velocity magnitude contours in the nose.
9. CAMP
Clarkson University
Pressure contours in the nose.
11. CAMP
Clarkson University
Sample Deposited
Glass Fibers
Comparison with
Experimental
Data
Sample
Trajectories
Fan and Ahmadi (1996)
Soltani and Ahmadi (1999)
12. CAMP
Clarkson University
Vacuum
Pump
Aerodynamic Lenses Nozzle (d=3 mm)
(d=5, 4.5, 4, 3.75, 3.5 mm)
Skimmer
50 mm
•To evaluate the performance Intermediate
of aerodynamic lenses for Chamber
generating focused beams of
nano-particles
Computational grid
Velocity Contours
13. CAMP
Clarkson University
Pressure Contours
d =100 nm
Particle Trajectories 20
eamD eter (mm)
16
Beam Diameter (mm)
Experimental Data (Liu et al. 1995b)
Conningham (varying pressure)
12
iam
Conningham (constant coefficient)
article B
8
P
4
0
0.00 0.05 0.10 0.15 0.20 0.25
Particles Diameter (micrometer)
Particle Diameter (µm)
14. CAMP
Clarkson University
Computer Simulation of
concentration behind the building
Experimental helium
concentration data
measured by Mirzai et
al. (1994)
15. CAMP
Clarkson University
Velocity magnitude contours.
Pollutant concentration contours.
16. CAMP
Clarkson University
Buffalo
Canada
Lwebuga-Mukasa (2001)
17. CAMP
Clarkson University
Peace Bridge Canada
Buffalo
Lwebuga-Mukasa (2001)
19. CAMP
Clarkson University
Fl
Mt
Ft d
O
a
FPo
•Cryogenic Surface Cleaning
(Toscano and Ahmadi (2002)
•Particle Removal in Turbulent
Flows (Soltani, Fan and Ahmadi (1995)
•Removal by Vibration
20. CAMP
Clarkson University
Fully Coupled Electro-hydrodynamic
System of Equations are solved
21. CAMP
Clarkson University
Plate
Gas
Flow Corona Wire
Plate
22. CAMP
Clarkson University
Electrode
Positive Ion
Negative Ion/
Electron
Ionized Sheath
+ Wire
23. CAMP
Clarkson University
Single Wire Precipitator
Plate
Gas
Flow Corona Wire
Plate
Kaptsov’s Assumption and Peek’s Formula were used
28. CAMP
Clarkson University
25
12
20 Computational result
Voltage (dimensionless)
Voltage (dimensionless)
Penny and Matick
9
15
6
10
5 3
0 0
0 0.25 0.5 0.75 1 0 0.25 0.5 0.75 1
Y (dimensionless) Y (dimensionless)
29. CAMP
Clarkson University
No cross-flow Inlet velocity 0.2 m/s
Intel velocity 3 m/s Inlet velocity 6 m/s
30. CAMP
Clarkson University
14
14
Inlet
Inlet
Outlet 12 Outlet
12
Voltage (dimensionless)
10
Voltage (dimensionless)
10
8
8
6
6
4
4
2
2
0
0 0 0.25 0.5 0.75 1
0 0.25 0.5 0.75 1 Y (dimensionless)
Y (dimensionless)
No cross-flow Inlet velocity 0.2 m/s
14 14
Inlet
Inlet 12 Outlet
12
Outlet
Voltage (dimensionless)
Voltage (dimensionless)
10
10
8
8
6
6
4
4
2
2
0
0 0 0.25 0.5 0.75 1
0 0.25 0.5 0.75 1 Y (dimensionless)
Y (dimensionless)
Intel velocity 3 m/s Inlet velocity 6 m/s
31. CAMP
Clarkson University
No cross-flow Inlet velocity 0.2 m/s
Intel velocity 3 m/s Inlet velocity 6 m/s
32. CAMP
Clarkson University
No cross-flow Inlet velocity 0.2 m/s
Intel velocity 3 m/s Inlet velocity 6 m/s
33. CAMP
Clarkson University
Current Flux Inlet Plate
Velocity Current
J = (qu + bqE − D∇q)
No cross flow 5.84 e-5 A/m2
0.2 m/s 5.83 e-5 A/m2
Current received by
each Plate 3 m/s 5.70 e-5 A/m2
J py = ∫ bqE y
6 m/s 5.53 e-5 A/m2
34. CAMP
Clarkson University
Inlet Velocity Wire Charge
Density
No cross flow 5.64 e-5 C/m3
0.2 m/s 5.66 e-5 C/m3
3 m/s 5.73 e-5 C/m3
6 m/s 5.90 e-5 C/m3
36. CAMP
Clarkson University
Electric Potential and Charge Density Contours
Electric Potential Charge Density
Contours Contours
37. CAMP
Clarkson University
0.001
400 0.0009
0.0008
Voltage (Volt)
300
0.0007
3
C/m
200 0.0006
0.0005
100
0.0004
0 0.0003
0 5 10 15 20 0 100 200 300
Length (mm) Φ
Voltage Profile on the Charge Density
Substrate Profile on the wire
38. CAMP
Clarkson University
• Develop a sequence of interactive web-based
courses on particle transport, deposition and
removal
• Provide computational modeling experience
• Provide hands-on laboratory experience
http://www.clarkson.edu/fluidflow/courses/me437/syllabus.htm
http://www.clarkson.edu/fluidflow/courses/me537/syllabus.htm
http://www.clarkson.edu/fluidflow/courses/me637/syllabus.htm
39. CAMP
Clarkson University
• Computer modeling provide an
important tool for studying
environmental flows
• Numerical simulation is a useful tool
for design of corona devices
Goodarz Ahmadi
Clarkson University Fa-Gung Fan
(315) 268-2322 Xerox Corporation
ahmadi@clarkson.edu FFan@crt.xerox.com