Mozzarino 7 Posted January 7 (edited) Hi, I'm trying to understand how the divergence field works in Houdini, and how it interacts with FLIP fluid particles. Positive divergence should cause the fluid to expand but there seems to be a difference between having positive values in the divergence field and having positive values of divergence in the particles attribute: -If I have positive values of divergence in the particles attribute, the field copies this values (or does some other math operation) and the fluid expands. -If I have positive values of divergence in the field, the particles don't inherit any divergence and the fluid stays the same. -If I disable the option "Divergence by attribute" and have positive values of divergence in the field, the fluid also stays the same. Another thing I can't understand: If I want to fill a volume of 1m^3 using the gasequalizevolume micro-solver with the paramater "Scale Goal Volume" set to 0 then, according to Houdini's Documentation I have to change the parameter "Add Goal Volume" and set it to 1. I tried this and the FLIP solver simply copied the value 1 to the divergence field which doesn't result in any change on the fluid surface. Could some one shed some light on this behaviour, and what is the correct approach to fill specific volumes knowing the total volume value? EDIT: The divergence field is actually working as intended, I was modfying it in the sourcing input rather than in the velocity volume input... Edited January 7 by Mozzarino Share this post Link to post Share on other sites