OpenFOAM - How to create ZeroThicknessWall in SnappyHexMesh? Also Can I use toposet (or splitmesh) to create zone for adding momentum source in buoyantBoussinesqFoams?

How to create ZeroThicknessWall in SnappyHexMesh? Also Can I use toposet (or splitmesh) to create zone for adding momentum source in buoyantBoussinesqFoams?

Hi,

I'm working on data center CFD analyses. I noticed that mesh elements near the racks is very small due to the rack thickness. So I planned to create zerothickness wall for rack geometry so that I can create coarse mesh. is there any option other than toposet (split mesh) to create zero thickness wall.

In my 2nd query, I need to add some momentum source. I noticed that toposet again can be used to create the cellzone where I can add momentum source but I'm concerned whether I need to shift to CHT..foams or I can still use BuoyantBoussinesq...foam.

Regards

Dr. Ijaz Fazil

OpenFOAM 29-10-20, 6:13 p.m. drijazfazil

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Dear Dr. Fazil,

The method I usually go with to create zero thickness walls is to extract/create face zones using topoSet utility and then use those face zones to create walls using creatBaffles utility.

Regards,
Ashley

02-11-20, 2:46 p.m. ashleymelvin

Dear Ashley,

Thank you so much, I'm also working on the same strategy now.

Is it feasible to use 'stl' files to create facezone?

Regards

Dr. IjazFazil

02-11-20, 3:03 p.m. drijazfazil

Dear Dr. Fazil,

I haven't used toposet yet using stl files. But I found a forum post, linked below, that you might find helpful.

https://www.cfd-online.com/Forums/openfoam-pre-processing/208359-creating-patch-stl-surface.html

Regards,

Ashley

03-11-20, 12:16 a.m. ashleymelvin

Dear Ashley, Thank you

03-11-20, 8:40 p.m. drijazfazil

Dear Dr. Fazil, You could refer one tutorial for reference. multiphase/interFoam/RAS/damBreakPorousBaffle: There you can find createBafflesDict without any stl file. That tutorial is for cyclic patch, but you can use to add momentum. To add momentum, you can use fvOptions dictionary. Regards, Divyesh

02-11-20, 3:36 p.m. divyesh

Dear Divyesh,

Thank you. But I need to stl files, as team members find little difficult to create seperate geometry 'toposet' for one component alone. So I thought of creating stl files and use that particular stl file for toposet and others for snappyhex

Regards

Dr. Ijaz Fazil

02-11-20, 4:20 p.m. drijazfazil

Thank you so much, I'm also working on the same strategy

03-11-20, 12:08 a.m. RoyKCarollJ456

Dear all, I came across this tutorial "\combustion\reactingFoam\RAS\membrane". In which facezone from stl file is defined in snappyhexmesh instead of toposet and then createbaffles used to create zerothickness wall (baffles). Regards Dr. Ijaz Fazil

04-11-20, 8:52 p.m. drijazfazil

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