[liuchaofu]

I calculate a jet cooling problems use Openfoam，Then I use the Tecplot post-processing，But I can't output the Nusselt number，or the heat transfer coefficient。Who can help me？

[Tushar@cfd]

Originally Posted by liuchaofu

I calculate a jet cooling problems use Openfoam，Then I use the Tecplot post-processing，But I can't output the Nusselt number，or the heat transfer coefficient。Who can help me？

Well, you can output the variable using utility, please refer the following link for more information...
write out nusselt number (gradient of T, respectively) for timesteps

[liuchaofu]

Thank you for your reply.Because I am a newbie on OpenFoam,I only can output the temperature and speed using Tecplot.Can you tell me what variables wo should output to get Nusselt number and the methods.Thank you .

[liuchaofu]

I have to OpenFoam version 2.1.1. I want to use the wall heat flux function.But when I enter this command.It shows this function could not be found.How should I set.Because I is the isothermal wall condition.I need to output the wall heat flux to calculate heat transfer coefficient

[Tushar@cfd]

Originally Posted by liuchaofu

I have to OpenFoam version 2.1.1. I want to use the wall heat flux function.But when I enter this command.It shows this function could not be found.How should I set.Because I is the isothermal wall condition.I need to output the wall heat flux to calculate heat transfer coefficient

In the weblink:
write out nusselt number (gradient of T, respectively) for timesteps

Check this code:
###################
volScalarField gradT ( IOobject ( "gradT", runTime.timeName(), mesh, IOobject::NO_READ, IOobject::AUTO_WRITE ), mesh, dimensionedVector ( "gradT", T.dimensions()/dimLength, 0 ) ); label patchi = mesh.boundaryMesh().findPatchID("myPatch"); gradT.boundaryField()[patchi]=T.boundaryField()[patchi].snGrad(); runTime.write();

#####################

This is similar to the $utility/Postprocessing/wall/wallGradU file.
Copy this file and make new wallGradT file.
You need to put T instead of U, as mentioned above. Then try to compile the same. After you finish with this, run the utility in the case folder.