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ucns3d-team / UCNS3D

Unstructured Compressible Navier Stokes 3D code (UCNS3D)
https://ucns3d.com
GNU General Public License v3.0
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result of 3d is abnormal #22

Open aerosky-689 opened 2 years ago

aerosky-689 commented 2 years ago

recently, I use onera m6 wing to test RANS, the equation is navier-stokes, SA turbulence model, the calculation is convergent, and pressure and density are normal on the surface of wing. however, U velocity is not zero on the surface, velocity on the viscous wall should be zero? so I have some doubt, can you give me some advice about it.

TakisCFD commented 2 years ago

the velocity at the wall is zero, however in the surface output the volume averaged values at the first cell off the wall are written at the surface. Hope this helps.

aerosky-689 commented 2 years ago

I want to execute iLES and DDES, however, it always get a steady result , or even could be divergent. I have some problem about input parameters, how to set up parameters specially about iLES and DDES in the UCNS3D.DAT file, compared with RANS?

TakisCFD commented 2 years ago

For iLES you need to ensure that for the code profile you specify option 0, and that you do not specify any explicit turbulence model. Then it is down to your preference if you are going to use the implicit time stepping or explicit time stepping.

For DDES the unless you specify the time stepping to be unsteady (options 3,4,11,12) it will run in a steady state mode. Please refer to the readme parameters txt file in the main directory.