After the decision to switch to sparse pyro in Houdini 18, several issues have been solved. Thinness and choppiness of the flame is gone and it is now quick to sim. But I am learning that sparse pyro is difficult to shape. It also seems to be exporting fields differently when caching VDBs. This is causing issues when bringing the VDBs into Arnold in Maya for rendering. I have not found a solution yet to the Arnold problem but I hope to have it worked out by the beginning of next week.
EDIT: The issue with bringing sparse pyro VDBs to Arnold Maya has been fixed. The arnold documentation recommends converting to VDBs then caching out those VDBs. This is not the case with sparse pyro. Just attaching the file cache to the Pyro Post-Process node that is created when using a sparse pyro preset, and checking the “convert VDBs” checkbox will create functional VDBs.
Issues with the render farm has resulted in our video not having all the sims in it. I have locally rendered my exhaust sim and comped it over our video. The timing is slightly off, probably due to this being a separate render.