Discussion Forum

I am using the Phase Field Method to simulate a micro-sized oil droplet in water (that should float up due to its lower density). My model works fine when the droplet is mm sized; however, as I reduce the dimensions of the modeland the droplet down to a um scale, the droplet disappears. Theoretically, I have not accounted for drag forces yet in my model, so the velocity with which it floats up should not depend on the droplet size, hence I am keeping the velocity (used to define the mobility tuning parameter using velocity) constanr. I tried making the interface thickness parameter smaller, and making the mesh finer, and although that stops it from disappearing, it causes another new problem- the droplet doesn't float up anymore (it stays stationary). Does anyone have any suggestions as to how to methodically tune the interface thickness and mobility tuning parameters, instead of just trial and error that I'm doing right now? Any suggestion or resource would be greatly appreciated.