On Apr 29, 2013, at 5:45 PM, Frederic Durodie <[email protected]> wrote:
> In a simple 2D heat conduction problem I try to impose a power flux on > part of the outer boundary and a fixed temperature on the remaining > part. > > However the resulting temperature distribution is not what I expect and > furthermore depends on how the problem geometry is rotated (alphadeg : I > did this to try and understand what is happening). > > To impose the powerflux I use the method described in > http://matforge.org/fipy/wiki/BoundaryConditions. That wiki page is a bit misleading, as it says that you are specifying $\hat{n}\cdot\nabla\phi$ (a scalar), when in fact you need to specify $\nabla\phi$ (a vector). The official documentation: http://www.ctcms.nist.gov/fipy/documentation/USAGE.html#applying-fixed-gradient-boundary-conditions-neumann is more accurate, in that it makes it clear that the constraint must be rank-1, but still not as helpful as it could be. I believe what you want is T.faceGrad.constrain(PowerFlux/K * mesh._faceNormals, where=mesh.physicalFaces["semi circle"]) _______________________________________________ fipy mailing list [email protected] http://www.ctcms.nist.gov/fipy [ NIST internal ONLY: https://email.nist.gov/mailman/listinfo/fipy ]
