Dump/restore issue with Multigrid, grid depths do not match

[Brandon Aranda]

Hi,

I am running a simulation using multigrid3D to create a rectangular domain with an aspect ratio of 40 (the length in the x-dimension is 40x those of y and z). However, when trying to restart the simulation, I kept running into the error message "grid depts do not match. Aborting." After some testing, I believe I narrowed it down to an issue with the aspect ratio. With an aspect ratio of 8, I am able to restart the simulation. Increasing the aspect ratio to 10 causes the restart to fail. Are there any suggestions on how to go about this issue?

Thanks,

Brandon Aranda

[Krishnaprasad K.A.]

Hey Brandon,

I've been experiencing the same issue. Were you able to find the fix to continue restarting/running with larger aspect ratios?

Regards,

Krishnaprasad

[Brandon Aranda]

Hi Krishnaprasad,

From my testing, it seems that the issue is that Basilisk can only restore the simulation when the mesh has an exact power of 2 in each dimension i.e. 2, 4, 8, 16... cells in every dimension. Therefore, you can only restart if your aspect ratio is also a power of 2. The only "fix" in that case is to make your geometry a little bigger. In my case, I was trying to simulate a 40x1x1 channel and instead I simply extended it to a 64x1x1 channel. Depending on your problem, you may or may not be able to do this or may need to include an embedded boundary along with this fix to create your geometry.

Brandon Aranda