Thanks, Jozsef for the video. You mentioned at 4:48 that it is possible to specify external heat flux as a csv file. I am trying to implement a csv file that is supposed to have time-varying external heat flux values for each patch of my mesh. You showed how to specify the heat fluxes as tabular inputs, but can you also tell me how to do this using an external csv file?
Hello József. Very informative video. However, I get an error using this BC. error: Using kappaMethod fluidThermo, but thermo package not available I searched similar cases, and two possible causes were defining fluidThermo for a solid region or using this BC for an incompressible solver. Neither of these is my case. Thermophysical properties of the fluid fields contain mu and Pr numbers, so the solver should be able to calculate kappa but the error is insisting. More details and case files can be provided as well. Many thanks. In general, the lack of an informative video on chtMultiRegionFoam or chtmultiRegionTwoPhaseEulerFoam is annoying :D
Thanks Jozsef, very informative video! BTW, do you know if h (htc) can be a temperature dependent function? since it uses "PatchFunction1" type of patch.
In case I would like to apply a free convection BC, like "mode coefficient" but in a solid transfern analisys with solver lapladianFoam, is it possible to use this BC and in combination of what kind of options?
Thank you very much for this video. Just was rechecking the destination of files. I think it is this one - /usr/lib/openfoam/openfoam2212/src/thermoTools/derivedFvPatchFields/ ( Use list command to see all the options)
Hello, I'm receiving this error when I try to use this BC to my heater. --> FOAM FATAL IO ERROR: (openfoam-2212 patch=230110) Unknown patchField type externalWallHeatFluxTemperature for patch type patch
Hi Jozsef, this boundary condition as you mentioned can be used in other solver besides cht solver. I did not add kappamethod but it shows error where it says --> FOAM FATAL ERROR: Cannot find a fluidThermo or solidThermo instance From function Foam::tmp Foam::temperatureCoupledBase::kappa(const Foam::fvPatchField &) const in file derivedFvPatchFields/temperatureCoupledBase/temperatureCoupledBase.C at line 133. May I know if I did anything wrong or did not add?
@@OpenFOAMJozsefNagy Yes, thank you for your reply I did not use chtmultiregion solver but my own modified interFOAM solver. Do you happen to know what changes is needed to make this BC work for interfoam?
@@OpenFOAMJozsefNagy Yes I understand that, however, Im not sure how to tell which header files and libraries to link in order to use this properly. Do you happen to know?
Hello, Mr. József Nagy. I really appreciate for your kind explanation for this B.C. Actually, I have been some trouble using it. I have tried to Two-phase simulation with condensation & evaporation (solver is intercondensatingevaporatingFoam) if water passed in pipe, the wall of pipe temperature is alright. But if vapor passed in pipe, temperature goes extremely high.... Do you have experience such as mine? Thank you for this video again.
Hello! I have problems using this BC with the heat flux mod (fluidThermo). When I postprocess my result with utility wallHeatFlux I get zero flux on patch but for example wallShearStress is not zero. What's kind of this problem?
@@OpenFOAMJozsefNagy Tnx for your recommendation. I've checked header file "externalWallHeatFluxTemperatureFvPatchScalarField.H", but I didn't find answer for my question. I do all things according to description and get different temperature on patch. Also I have tried to use heatTransferCoeff, so results is similar to wallHeatFlux. Meybe troubles in alphaEff()? Could you give another one advise?
Hi József Nagy I try to implement heat flux value as a table in the simulation based on the location. In the video you told that you did not use at 7:15 but do you have any web side or document in order to apply heat flux value based on the location. I have a nonuniform heat flux value correseponding to x,y, and z values. I am not sure which file needs to be modified.
@@OpenFOAMJozsefNagy For the non uniform heat flux value, I successfully modified the T file. I was use the another application to calculate radiation over the wall. After that interpolated the value that I found for the radiative heat flux. Impose as a boundary condition for the heat flux in the T file with using external wall heat flux BC for the corresponding walls. In order to do that, the cell centre of the walls is used. same order of the meshes is used.
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Thanks, Jozsef for the video.
You mentioned at 4:48 that it is possible to specify external heat flux as a csv file. I am trying to implement a csv file that is supposed to have time-varying external heat flux values for each patch of my mesh.
You showed how to specify the heat fluxes as tabular inputs, but can you also tell me how to do this using an external csv file?
Muy buen video. Explicas muy bien toda la información.
Hello József. Very informative video. However, I get an error using this BC. error: Using kappaMethod fluidThermo, but thermo package not available
I searched similar cases, and two possible causes were defining fluidThermo for a solid region or using this BC for an incompressible solver. Neither of these is my case. Thermophysical properties of the fluid fields contain mu and Pr numbers, so the solver should be able to calculate kappa but the error is insisting. More details and case files can be provided as well. Many thanks.
In general, the lack of an informative video on chtMultiRegionFoam or chtmultiRegionTwoPhaseEulerFoam is annoying :D
Do you maybe use a different version of OF?
@@OpenFOAMJozsefNagy Hi. Thanks for the response. I am using v2112
Thanks Jozsef, very informative video! BTW, do you know if h (htc) can be a temperature dependent function? since it uses "PatchFunction1" type of patch.
No, currently it can only be time dependent. You have to program this yourself.
In case I would like to apply a free convection BC, like "mode coefficient" but in a solid transfern analisys with solver lapladianFoam, is it possible to use this BC and in combination of what kind of options?
This is a basic solver I do not think there is this BC. Which BC do you exactly mean? What is the OpenFOAM name?
@@OpenFOAMJozsefNagy I would like to use a free convection BC with the LaplacianFoam solver
Thank you very much for this video. Just was rechecking the destination of files. I think it is this one - /usr/lib/openfoam/openfoam2212/src/thermoTools/derivedFvPatchFields/ ( Use list command to see all the options)
Hello, I'm receiving this error when I try to use this BC to my heater.
--> FOAM FATAL IO ERROR: (openfoam-2212 patch=230110)
Unknown patchField type externalWallHeatFluxTemperature for patch type patch
Check the tutorials in OpenFOAM-v2212/tutorials/heatTransfer/chtMultiRegionFoam/ for more info
Hi Jozsef, this boundary condition as you mentioned can be used in other solver besides cht solver. I did not add kappamethod but it shows error where it says
--> FOAM FATAL ERROR:
Cannot find a fluidThermo or solidThermo instance
From function Foam::tmp Foam::temperatureCoupledBase::kappa(const Foam::fvPatchField &) const
in file derivedFvPatchFields/temperatureCoupledBase/temperatureCoupledBase.C at line 133.
May I know if I did anything wrong or did not add?
In your solver fluidThermo is somehow not defined.
@@OpenFOAMJozsefNagy Yes, thank you for your reply I did not use chtmultiregion solver but my own modified interFOAM solver. Do you happen to know what changes is needed to make this BC work for interfoam?
@@stanleywong9004 Yes, interFOAM does not use thermophysical properties by default. You have to add it to the code.
@@OpenFOAMJozsefNagy Yes I understand that, however, Im not sure how to tell which header files and libraries to link in order to use this properly. Do you happen to know?
Hello, Mr. József Nagy.
I really appreciate for your kind explanation for this B.C.
Actually, I have been some trouble using it. I have tried to Two-phase simulation with condensation & evaporation (solver is intercondensatingevaporatingFoam)
if water passed in pipe, the wall of pipe temperature is alright. But if vapor passed in pipe, temperature goes extremely high....
Do you have experience such as mine?
Thank you for this video again.
Unfortunately I do not have any experience with that solver.
@@OpenFOAMJozsefNagy Thank you for reply
Hello what is the difference between externalwallheatfluxtemperature's "Q" and fixedGradient boundary condition
The first has three modes available and calculates the gradient for you. For the other you have to do the calculation yourself. So user friendliness.
Hello! I have problems using this BC with the heat flux mod (fluidThermo). When I postprocess my result with utility wallHeatFlux I get zero flux on patch but for example wallShearStress is not zero. What's kind of this problem?
Check the header file of the source code.
@@OpenFOAMJozsefNagy Tnx for your recommendation. I've checked header file "externalWallHeatFluxTemperatureFvPatchScalarField.H", but I didn't find answer for my question. I do all things according to description and get different temperature on patch. Also I have tried to use heatTransferCoeff, so results is similar to wallHeatFlux. Meybe troubles in alphaEff()? Could you give another one advise?
Hi József Nagy
I try to implement heat flux value as a table in the simulation based on the location. In the video you told that you did not use at 7:15 but do you have any web side or document in order to apply heat flux value based on the location. I have a nonuniform heat flux value correseponding to x,y, and z values. I am not sure which file needs to be modified.
Unfortunately not.
@@OpenFOAMJozsefNagy For the non uniform heat flux value, I successfully modified the T file. I was use the another application to calculate radiation over the wall. After that interpolated the value that I found for the radiative heat flux. Impose as a boundary condition for the heat flux in the T file with using external wall heat flux BC for the corresponding walls. In order to do that, the cell centre of the walls is used. same order of the meshes is used.
@@oguzhanask1284 Cool!
only works for compressible??
Yes