> On Jun 23, 2016, at 10:23 AM, Daniel Wheeler <daniel.wheel...@gmail.com>
> wrote:
>
> I'm not sure what the thinking is of your colleagues, but the size of
> the elements has little or no impact on conservation. In finite
> volume, the equations are conservative to at least the precision of
> the linear solver (if not more) independently from the accuracy of the
> solution. Of course there could be an issue with source terms that I'm
> not seeing, but the diffusion and convection terms should be entirely
> conservative.
I think the bigger issue is that a Grid1D will not properly represent a
spherical divergence, regardless of the volumes of the cells. I thought we had
a set of SphericalGrid1D classes, but apparently not. It would be the same
basic idea as CylindricalNonUniformGrid1D, but I think the cell volumes and
face areas would need to be changed, I believe like this:
def _calcFaceAreas(self):
r = self._calcFaceCenters()[0]
return r**2
def _calcCellVolumes(self):
return super(CylindricalNonUniformGrid1D, self)._calcCellVolumes() / 3.
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