SimScale CAE Forum

Supersonic Flow Over a Wedge


#1

Hello!

I’m trying to simulate a supersonic flow over a wedge. I want to simulate a high speed flow of Ux=915m/s and try to visualize the shock waves. I’m pretty new at setting up simulations and I’m not sure if I’m doing it right. I’ve run a number of simulations which have all crashed due to a number of errors. I’m nut sure if the problem is with the mesh, initial or boundary conditions, or simulation control.

Project: https://www.simscale.com/projects/jpryning/software_exercise_6/

Any help that I can get would be appreciated.

Thanks!


#2

Hey there and nice project!

I think @Get_Barried has worked on this in the past and has some projects he can let you know about. Also have the wedge geometry in my Dashboard but haven’t try a run yet :slight_smile:

Edit: Found the one from Barry- https://www.simscale.com/projects/Get_Barried/compressible_flow_diamond_airfoil_validation_2/

Cheers,

Jousef


#3

hi @jpryning
in your B.C. set up, you used Empty 2D condition but your model is 3D not in 2D so, have to remove that condition
OR
you have to make 2D geometry to use Empty 2D BC. to do that follow this video and for more info on this old post.

Cheers!
Rohit.


#4

Thanks for your response!
I had a look at Get_Barried’s project and it was helpful. I think I have mesh problems and will have to work on refining it and making it a 2D problem. I did notice in Get_Barried’s project that he calls it Mach flow but the velocity is only 2m/s. Does the Mach condition come from changing the material properties to artificially create it?

Jpryning


#5

Thanks for the reply @ROHIT_SR. I’ll try and change my mesh. I am trying to make a 2D problem so I just assumed I could apply that boundary condition. Now I know, thanks!

Jpryning


#6

Hi @jpryning,

Yes I have normalized air to let the speed of sound be 1m/s.

So 2m/s would mean a Mach 2 flow speed.

This makes indication of the inlet speed directly as mach number and makes it less prone to calculation errors from other material or inlet conditions.

Cheers.

Regards,
Barry


#7

Thanks @Get_Barried. That makes sense, and it is a simpler way of looking at the velocity.

jpryning