[ravikanthmannem]

Hello,
I tried solving a pipe flow case where heat transfer occurs at a portion of pipe where there is uniform heat flux using buoyantboussinesqsimplefoam. But i'm getting an incorrect solution. Can anybody send me a case file for the problem in the below link

https://confluence.cornell.edu/displ...ced+Convection

[rakeshc]

Hello, Ravi

have you solved your problem,.. i am also trying the same case of turbulent pipe flow, where heat transfer occurs at a portion of pipe and there is uniform heat flux using buoyantboussinesqsimplefoam . With gravity and beta i am getting mass flow imbalance at inlet outlet whereas for g and beta =0 solution is converging.

thanks...

[agustinvo]

Hi

as far as I see, you should do three different groups of blocks with blockMesh, so you can use different BC's at the walls. The, just look for the heat flux boundary condition, by using swak4Foam, a fixedGradient, or implementing the BC you're looking for.

[rakeshc]

thanks for reply..
I am using different boundary name for heat flux in the middle part of pipe and rest is adiabatic...and also i tried different heat flux boundaries as mentioned by you i.e. groovy, a fixedGradient, or implemented BC for heat flux or power but solution is diverging with gravity (g) on, in buoyantBousinesqSimpleFoam solver for this force convection pipe flow in OpenFOAM-4.1....
can we use buoyantBousinesqSimpleFoam solver for force convection problem for turbulent flow of incompressible fluids....

thanks...

[agustinvo]

Hi

what you can do is to set the gravity equal to zero (so there is no buoyancy forces), or you add the temperature equation in simpleFoam

[rakeshc]

thanks for quick reply...

I tried it without gravity and solution is converged and predictions are good. But i want the effect of buoyancy term for my actual problem using boussinesq approximation for incompresible force convection. Buoyancy would be affect the predictions, it can not be neglected ... This pipe flow is a test case.....

[agustinvo]

Hi

could you post your setup and the log of your case? Maybe there we can find the problem

[rakeshc]

hi..
please find attached test case...your help is very helpful for me

thanks..

[tintintk]

Originally Posted by rakeshc

hi..
please find attached test case...your help is very helpful for me

thanks..

Hello rakesh, did you find the solution to your problem. I am facing the same issue.Can you please help me?