[PanPeter]

Hi,

I interested in the flow- and heat distribution in a channel and fail to map the temperature back to the inlet.
The flow field is periodic, the pressure drops and the temperature increases downstream (channel wall heating).

These are my boundary conditions:
Inlet:

U=mapped U(outlet)
p=zeroGradient
T=mapped T(outlet), average = f(T(outlet))

Outlet:

U=zeroGradient
p=zeroGradient, reference pressure set at some face
T=zeroGradient

The temperature field is not periodic because of its build-up along the wall. But as described in http://heattransfer.asmedigitalcolle...icleid=1436662, the dimensionless temperature

is periodic. are the constant wall temperature and a local reference temperature, respectively.

Now, I want to map the profile, while setting the average such that the dimensionless temperature is kept constant.

- I thought of using swak but it doesn't look like direct mapping and averaging is supported.
- So I thought of codeStreams next, to return an expression for the average option in the mapped BC. In the attached temperature BC for the inlet a dummy value is returned in the forth-last line. The problem arises already in the fith-last line. I'm looking up a patchField of the outlet temperature. Here the program crashes with the error message hanging pointer at index 1 (size 10), cannot dereference.

Does anybody have an idea what went wrong here or how this could be fixed?
Cheers
Fynn

 X0
    {
	type                mapped;
        value               uniform 0.01;
        interpolationScheme cell;
        setAverage          true;
        average             #codeStream
	{
	    codeInclude
		#{
			#include "fvCFD.H"
		#};
		codeOptions
		#{
			-I$(LIB_SRC)/finiteVolume/lnInclude \
			-I$(LIB_SRC)/meshTools/lnInclude
		#};
		codeLibs
		#{
			-lmeshTools \
			-lfiniteVolume
		#};
		code
		#{
	    	 const IOdictionary& d = static_cast<const IOdictionary&>
	    	    (
	    		dict.parent().parent()
	    	    );
	        const fvMesh& mesh = refCast<const fvMesh>(d.db());
	   	const label id = mesh.boundary().findPatchID("X1");
	        const fvPatch& patch = mesh.boundary()[id];
	    	const fvPatchScalarField& T = patch.lookupPatchField<volScalarField, scalar>("T");
		os<<0.0027;                       //dummy value
		#};
	};
    }