|
[Sponsors] |
BC and wall function for Smagorinsky LES turbulence model |
![]() |
|
LinkBack | Thread Tools | Search this Thread | Display Modes |
![]() |
![]() |
#1 |
New Member
Carmelo Baronetto
Join Date: Dec 2023
Posts: 29
Rep Power: 2 ![]() |
Good morning to all,
I'm trying to set a simulation of a compressible turbulent flow, using the Smagorinsky turbulence model. I'm not sure how to set boundary conditions for turbulence that means setting boundary conditions in the nut and alphat files. I have already run a simulation where I set "calculated" for both patches and walls (see code below). I guess that turbulence model computes all the variables using the pressure, temperature and velocity fields, and no other boundary conditions are necessary. In the this simulation, I set slip boundary conditions for walls, so that no boundary layer is formed. Now I would like to run another simulation with no slip conditon at walls to take into account the boundary layer. I don't know if I can use the same boundary conditions (I guess yes for type pathe bounaries) or if boundary conditions must be modified, using a wall function. I found two wall functions for nut, named "nutWallFunction" and "nutUSpaldingWallFunction", but I don't know if they can be useful in my simulation. Also, the mesh is quite fine but I don't know if I have to add some layers at the walls. I hope you can help me. Thank you for your time. Best Regards. Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: v2312 | | \\ / A nd | Website: www.openfoam.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class volScalarField; object nut; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 2 -1 0 0 0 0]; internalField uniform 0; boundaryField { "(inlet|tank)" { type calculated; value uniform 0; } "(HP_wall|nozzle_wall|tank_wall)" { type calculated; value uniform 0; } } Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: v2312 | | \\ / A nd | Website: www.openfoam.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class volScalarField; object alphat; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [1 -1 -1 0 0 0 0]; internalField uniform 0; boundaryField { "(inlet|tank)" { type calculated; value uniform 0; } "(HP_wall|nozzle_wall|tank_wall)" { type calculated; value uniform 0; } } // ************************************************************************* // |
|
![]() |
![]() |
![]() |
|
|