[mesa-users] BV frequency, gradients and mlt problems - bugs?

[Bill Paxton]

Hi,

Now, concerning N^2:

On Jan 2, 2013, at 9:58 AM, Jakub Ostrowski wrote:

> My first problem are the weird spikes that you can see. Some of them look like they have a bad sign, that means they should go to zero instead of infinity, but there are also peeks which don't seem to be related to presence of any convective zone. Has anyone else experienced similar problem? For me it looks like numerical problem, but of course I might be wrong.

Take a look at this plot (thanks to Dennis Stello for this lovely plot design).    convection zones in gray.
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I think the "weird spikes" you mention are the peaks in N that match up with sharp transitions in abundances of H and He.

Keep in mind that parameters that control composition mixing will also impact the brunt.

For example, the results above are with no semiconvection, no overshooting, and no diffusion.
When I rerun with all of those enabled, I get this result instead -- notice that where N has changed,
so has the H/He profile.
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So, again, I don't see evidence of bugs.  just complex behavior.   

-Bill