[JoSchl]

Hello together,

I´m using Ansys AIM 18.0 and I wanna do an easy fluid flow around a sportscar to get the pressure conture of the car surface. But my problem is, the residuen do not reach the convergence criteria of 1E-05. they oscillateing all the time.
I prepared the geometry in Spaceclaim, just the car as a solid and using the enclose tool to get the simulated windchannel.
The meshing is automatically with curvature and proximity and put inflation layers on the body faces.
I´m using a steady/static calculation type, RANS and the k-omega-sst tubrbulence model. The fluid flow conditions are attached.
What I did so far was I tried different turbulence models (k-epsilon, spalart allmaras), did not use a symmetrie, and I decreased the solution advancement exponent from 0 to -1.
Does anyone have an idea whats the issue?
Thank you!

Greets

[JoSchl]

also attached the meshing and the residual control.

I found out that the highest residuals are right behind the car.

[TimH]

Hey

You could consider chaning the opening to walls - considering it a wind tunnel.
Else you could try using the steady state solution approach using a timescale. And keep the factor at 1 at first, then if no convergence you could try decreasing it. Remember to deactivate the funnel when looking for this option.

BR,
Tim

[TimH]

Try out transient, this is a very common problem.