[DenisPushin]

Hi, everyone.

I need to program a new BC allowing to prescribe a 3D parabolic velocity profile for circular inlet of a pipe with an arbitrary orientation in space (in foam-extend 3.1). In addition, I'd like to use average flow rate rather than velocity.

I started from parabolicVelocityFvPatchVectorField BC designed for prescribing parabolic profile only along one axis. Moreover, It is necessary to provide velocity and normal vector for this type of BC.

I changed the code for my purpose but faced the problems (described after the code). Below is a snippet of code (part of the function updateCoeffs) that works correctly for setting the velocity in the pipe oriented along coordinate axis (parabolicProfile.png).

boundBox bb(patch().patch().localPoints(), true);

vector ctr = 0.5*(bb.max() + bb.min());

const vectorField& c = patch().Cf();
vectorField n = patch().nf();

//scalar maxU = 2*(avgQ_ / gSum(patch().magSf()));

scalar patchRadius = mag(bb.max()-bb.min()) / (2 * sqrt(2.0));
scalarField coord = mag(c-ctr) / (patchRadius);

// maxU_ is read from the "0/U" dictionary.
vectorField::operator=((-1)*n*maxU_*(1.0 - sqr(coord)));

Problems
1) If I try to replace maxU_ with avgQ_ (uncomment the line and make the necessary changes in other places), I can compile the code and run calculations (using simpleFoam). But during the reconstruction of case I always get the error when reconstructing the velocity field. The error is float point exception. The question is how such code changing can lead to this error?

I would be grateful for any hint.

2) When the pipe is located with an arbitrary orientation, I always get the error immediately after run the case (listing below).

[13] —> FOAM FATAL ERROR: 
[13] 
gradientInternalCoeffs cannot be called for a genericFvPatchField (actual type parabolicInletFlowVelocity)
on patch rightInlet of field U in file "/home/denis/foam/denis-3.1/run/testParabolicBC/processor13/0/U"
You are probably trying to solve for a field with a generic boundary condition.
[13] 
[13] From function genericFvPatchField<Type>::gradientInternalCoeffs() const
[13] in file fields/fvPatchFields/basic/generic/genericFvPatchField.C at line 811.
[13] 
FOAM parallel run exiting

Is there any idea what this error means?

Thank you in advance.