Learning Forum

[Dennis Chen]

Hello, I want to inquire about if LSDyna ICFD solvers implement wall functions and where I can find some information about this?  

[ErKo]

 

Hello

 

Let me look into this.

 

In the mean time if you could help the user with this would be much appreciated (we can not download files).

Contact doesn’t work

 

Thank you

 

Erko

 

 

 

[ErKo]

 

 

SOme relevant info:

LS-DYNA’s ICFD (Incompressible Computational Fluid Dynamics) solver does implement wall functions for turbulence modeling. Specifically, for LES (Large Eddy Simulation) turbulence models, wall functions can be used, and for RANS (Reynolds-Averaged Navier-Stokes) turbulence models, the standard k-epsilon, realizable k-epsilon, and Wilcox k-omega models use HRN (High Reynolds Number) laws of the wall by default, while the SST and Spalart-Allmaras models use LRN (Low Reynolds Number) approaches. This allows users to select appropriate near-wall treatments depending on the turbulence model and the flow regime being simulated.

Technical documentation and further information about wall function support in LS-DYNA ICFD can be found in the “LS-DYNA Keyword and Theory Manuals Volume III,” particularly in the sections describing turbulence models and boundary layer treatments. For the latest and most detailed information, refer to the official Ansys documentation portal or the ICFD-specific documentation page (LSDYNA Documentation)

 

 

 

[Dennis Chen]

Hi Erko, thank you for gathering this information for me.   Can you please share with me the specific location where you found references to the wall function?  Is it in the documentation or in the theory manual?  I couldn't find it anywhere.... Maybe I missed something (that link you shared is obviously one of my first go to places haha). 

I also made a video to answer that other beam post :)  thought it was a good and fast/easy topic to make this week.   I am getting a little too busy at work, have not been able to do the stuff I want to do (like studying outside work). 

[Dennis Chen]

Hello, I forgot to add, I did find the references in the Vol 3 of the documentation but if there are more details elsewhere, please let me know, I really appreciate your help.   I am also looking at the Fluent documentation for comparison to help me learn. 

Thanks 

[ErKo]

 

Hello

Thinks the two manuals are good – also one can use AnsysGPT (bit of that 1st paragraph is from there :)) – if that does not help please raise a support ticket and we will be more than happy to help you.

Thank you, and again many thanks for the great help you provide in the forum here and in general with your youtube channel – much appreciated.

Erko