CFD Project during Masters Degree.

1. ME – 259 Introduction to Computational Fluid
Dynamics
Prof. Dongmei Zhou

2. Introduction
 CFD Model

3. Introduction
 Applications
River channel Bifurcation
Living Cardiovascular
system

4. Fluent Settings
 CFD Simulation: 3ddp (3-D Double Precision)
 Convergence criteria:
 Continuity = 1e-06
 X- velocity = 1e-06
 Y- velocity = 1e-06
 Z- velocity = 1e-06
 Discretization :
 Pressure : PRESTO
 Momentum equation setting = Second Order Upwind
 Solver : Coupled

5. Boundary Conditions (BC)
 BC 1 : Main channel Velocity Inlet
 BC 2 : Main channel Pressure Outlet
 BC 3 : Branch Velocity outlet

6. Procedure For study
 Grid Independent Study
 Creation of Different Mesh Files in GAMBIT ®
 Simulated in FLUENT® 3D
 Find Reattachment Length in Zone A
 Plot Truncation Error
 Parameter Study
 Simulated
Scenario 1 : Used Cases In Benchmark Paper

Scenario 2 : Change Fluid from water to Hydrogen

Scenario 3 : Keeping Reynolds Number constant changed

Discharge Ratio

7. Grid Independent Study
 Simulation results of Reattachment Length in Zone A
Reattachment Length in Zone A
% Error % Error
Analytical Re-
From From Best
Result attachment Error Error From
Analytical Mesh Size
from Mesh Size Length From Best
Or Or
Liepsch in Zone A Analytical Mesh Size
Truncation Truncation
Paper (meters)
error error
148176 2.42857 0.44847 15.58789589 0.43507 15.19290134
453600 2.48654 0.3905 13.57297778 0.3771 13.16855471
2.87704 1185408 2.64287 0.23417 8.139268137 0.22077 7.709418782
4000752 2.85714 0.0199 0.691683119 0.0065 0.226983839
4634784 2.86364 0.0134 0.465756472 0 0

8. Grid Independent Study
 Truncation Error Plots
Comparing with Liepsch Paper Comparing with Best Mesh Size

9. Grid Independent Study
 Streamline plots of velocity of Case 1 at Z = 2.0

10. Grid Independent Study
 Comparison of velocity profiles at Z=4.0 plane

11. Grid Independent Study
 Skin Friction Plots At Outer wall Of The Main
Skin Friction Plots At Branch Left wall
Right Wall
Channel

12. Grid Independent Study
 Z-plots of Vorticity Profiles at different positions of Y
keeping X constant

13. Grid Independent Study
 Z-plots of Vorticity Profiles at different positions of X
keeping Y constant

14. Parameter Study
 Mesh Size Used : 81 x 70 x 80
 Scenario Used
1. Study of Cases in Paper
2. Change of Fluid to Hydrogen
3. Keeping Re Constant Change Discharge ratio ‘r’

15. Parameter Study
 Scenario 1 : Study of Cases in Paper
Reynold Discharge Main channel
Branch Velocity Outlet
Case Ratio Velocity inlet
V2 (m/sec)
AR
Number r V1 = Ub (m/sec)
1 515 8 0.23 0.000258738 0.000059509
2 496 8 0.44 0.00024919 0.000109643
3 525 8 0.64 0.000026376 0.000168806
4 1062 8 0.58 0.000533548 0.000309458
5 496 1 0.44 0.00024919 0.000109643

16. Parameter Study
 Scenario 1 : Study of Cases in Paper
 Velocity streamline plots of the simulation

17. Parameter Study
 Scenario 1 : Study of Cases in Paper
 Velocity streamline plots of the Paper or benchmark

18. Parameter Study
 Scenario 2 : Change of Fluid to Hydrogen
Parameter Study Scenario 2 : Re-attachment Length
Discharge
Reynolds Reattachment
Fluid Ratio
number Length Xr (meters)
‘r’
Water 496 0.44 2.48654
Hydrogen 496 0.44 3.2

19. Parameter Study
 Scenario 2 : Change of Fluid to Hydrogen

20. Parameter Study
 Scenario 3 : Keeping ‘Re’ Constant Change Discharge ratio ‘r’
Reynold Discharge Ratio 'r' Main channel Branch Velocity
Number Inlet Velocity Outlet
V1 (m/sec) V2 (m/sec)
0.23 0.000059509
0.000258738
0.75 0.000194053
515 1 0.000258738
1.5 0.000388107
2 0.000776214

21. Parameter Study
 Scenario 3 Velocity Streamline plot at r = 0.23

22. Parameter Study
 Scenario 3 Velocity Streamline plot at r = 0.75

23. Parameter Study
 Scenario 3 Velocity Streamline plot at r = 1.00

24. Parameter Study
 Scenario 3 Velocity Streamline plot at r = 1.50

25. Parameter Study
 Scenario 3 Velocity Streamline plot at r = 2.00

26. Conclusion
 Grid Independent Study
Comparing with Liepsch Paper Comparing with Best Mesh Size

27. Conclusion
 Parameter Study Scenario 1

28. Conclusion
 Parameter Study Scenario 1

29. Conclusion
 Parameter Study Scenario 2

30. Conclusion
 Parameter Study Scenario 3

31. Conclusion
 Parameter Study Scenario 3

32. Conclusion
 Parameter Study Scenario 3

33. Conclusion
 Parameter Study Scenario 3

34. Conclusion
 Parameter Study Scenario 3

35. Questions