Discussion Forum

Hello friends,

I have a general question but I would formulate it from a particular problem. I want to simulate the fall of droplets of a liquid metal through a layer of another liquid metal; the two are immiscible with the droplets density higher than that of the surrounding metal.

It seems that the most appropriate module to use is Laminar Two-Phase Flow Level Set (tpf), because the Mixture Module (mm) does not offer the possibility to work with droplets of different sizes simultaneously; I mean one can generate a variable diameter for the dispersed phase droplets in time but how to distinguish their dynamics when the only information is in phid which is unique. True?

But the Laminar Two-Phase Flow Level Set (tpf) requires the introduction of a drop as a geometric primitive. This is fine for testing the model but if I want to generate a large number of drops with various values for diameter, initial velocity and position as a function of time, is there a way to feed in such a changeable geometry? I see three ways:

1) Use randomizing functions in the Geometry node with the functions defined within the Comsol file. Did anyone use this option?
2) Feed the drops as geometric primitives generated externally, making Comsol pick them up from a file. Is this possible? How can we make Comsol read a file?
3) Since the .mph file is a Java file, can one call specially designed Java classes, where the randomization functions and geometry primitives could be written?

Please let me know, if anyone encountered similar issues!
Thanks a lot!

Cristian