Replies: 4 comments · 9 replies
-
|
Does this also happen with a first order restart (start with first order timestepping, then restart with first order timestepping)? |
Beta Was this translation helpful? Give feedback.
-
|
I did not try first-order time stepping. And also, I did not do any EULER or N-S solver simulation. But I checked the same using URANS with SA Edwards without transition. I found a perfect match, no issue. |
Beta Was this translation helpful? Give feedback.
-
|
You can see how the restart of the transition simulation is affecting the result. Image 3: |
Beta Was this translation helpful? Give feedback.
-
|
OK, thanks, it is strange the behavior is completely different with a restart... maybe it's more than just a variable that is incorrectly re-initialized... First thing to check I guess is if we correctly save and restore the LM. You can write the residuals to screen of RMS_INTERMITTENCY and RMS_RE_THETA_T, in addition to the other residuals (it should be part of the SOLUTION variables, so if you write all SOLUTION variables, that should be fine). |
Beta Was this translation helpful? Give feedback.
-
|
I haven't tested the Transition model with URANS. If you keep restarting from the same iteration, are the results the same each time? Or are there differences? Setting the value of FREESTREAM_INTERMITTENCY won't change anything since the freestream value for gamma should always be 1.0 . The SA model is also unaffected by changes in the FREESTREAM_TURB2LAMVISCRATIO (the way to prescribe different values of nu_tilde at the farfield is with the FREESTREAM_NU_FACTOR option) . On the other hand, changing the FREESTREAM_TURBULENCEINTENSITY will lead to different results (the default value is 0.05, thus 5% TI). |
Beta Was this translation helpful? Give feedback.
-
|
Hi @bigfooted "relrms[Rho]", "relrms[RhoU]", "relrms[RhoV]", "relrms[RhoE]", "relrms[nu]", "relrms[LM_1]", "relrms[LM_2]" SU2 version: SU2-8.3.0; Transition model: LM-Madida Beader; Turbulence model: SA Edwards; Flow: Mach 0.730, AoA 4, Re 3x10^6, Airfoil: OALT25 Upon restart, RELRMS_INTERMITTENCY and RELRMS_RE_THETA_T change significantly. RELRMS_NU also changes. How to solve this? @rois1995 |
Beta Was this translation helpful? Give feedback.
-
|
For now, please stick with that option. I will try to fix it in the following days. |
Beta Was this translation helpful? Give feedback.
-
|
Thank you |
Beta Was this translation helpful? Give feedback.
-
|
Hi @rois1995, |
Beta Was this translation helpful? Give feedback.
-
|
Hi @MaganS Unfortunately, I did not have the time to do it. You should simply stick with that option and everything will be fine. Regarding the implementation of the model, there is a branch where I have implemented the gamma version of the LM model, you can try starting from that one. The branch is called feature_Trans_SLM and it has been extensively tested for 2D and 3D problems. For 2D it worked fine, but for 3D not so much compared to the gamma-Retheta model, although I think it is somewhat expected. |
Beta Was this translation helpful? Give feedback.
-
|
Ok, thank you |
Beta Was this translation helpful? Give feedback.
Uh oh!
There was an error while loading. Please reload this page.
-
I am doing transition simulations on an airfoil.
I am using the LM transition model and the SA Edwards turbulence model.
When I restart my simulation from a specific time step, the results do not match those obtained without a restart, as shown in the image.
SU2 version: SU2-8.3.0; Transition model: LM-Medida-Beader; Turbulence model: SA Edwards; Flow: Mach 0.735, AoA 4, Re 3x10^6, Airfoil: OALT25
I commented the following when I restarted, but that does not solve the problem.
FREESTREAM_TURBULENCEINTENSITY = 0.001
I am using only the above parameter in my config file. My config file
su2_unstdy.txt
The following parameters are set by default for my simulation because I have not specified them in my config file.
% Value for freestream intermittency
FREESTREAM_INTERMITTENCY= 1.0
Free-stream ratio between turbulent and laminar viscosity
FREESTREAM_TURB2LAMVISCRATIO= 10.0
Please suggest. Any help can make a big difference.
Thank you
Best,
Magan
Beta Was this translation helpful? Give feedback.
All reactions