July 14, 2022 at 2:27 amthaipham0815Subscriber
I was running a 2D simulation and I am wondering why the velocity at the outlet is so much higher than the inlet. I know that it is impossible, but what in ansys might be causing this issue. I will include the simulation conditions below. If there is something else that I did not include, it mostlikely means that I did not mess with those settings.
Solver: Transient, Pressure Based
Number of Time Steps: 600
Time Step Size: 1s
Max Iterations/Time Steps: 20
Fluid material: Water-Liquid
Mesh cell size: 0.0005m
Inlet velocity = 0.115 m/s
Wall = No Slip
Outlet Gauge Pressure = 0 Pa
As you can see, the outlet is 0.19 whereas the inlet is only 0.115. If anyone has any information on this, please let me know. Thank you!
July 14, 2022 at 6:18 amDrAmineAnsys Employee
Is the case converged?
Can you assess the Mass Flow at inlet / outlet and check the overall mass imbalance.
You have recirculating flows in both cavitities and so I won't rely much on velocity at the outlet but rather if the whole system is conserved! (Check if you have at the outlet reversal flow.. I aslo see large blue regions there telling me that not the whole outlet region is "feeling" the inflow... which is to be expected giving the flow bubbles/separations/reattachements you have).
July 14, 2022 at 11:08 pmthaipham0815Subscriber
What corrective actions would I go about to fix this issue. I have tried looking through a couple theory books and could not figure it out. As you can probably tell, I am very new to ansys..
July 18, 2022 at 9:26 amDrAmineAnsys Employee
Why do you think you require corrective actions? Just ensure you are converging deep and using proper BC's and Turbulence Modelling. If you have strong reversal flow at outlet try to place it bit flow downwards.
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