Help Needed for Simulation of Dropping Liquid into a Pool

[sparky977]

hi,
I am preety new in this field so I need some help about Comsol sw.
I would like to perform a simulation but as I am not a physicist I have no idea how to. So, if anyone can help me, I would be very happy.

OK. I would like to simulate the drop of liquid(water) which falls into a liquid pool. the drop can be simulated with the force of gravity or certain velocity of the drop.
the problem is preety easy to describe, but it is very hard to set up the system for the simulation.

Please, if someone can help me ... contact me.

thank you in advance.
regards,
sparky

 

[PerennialII]

You really do start from the (very) hard end of things . I think there is a "bunch" of people working just with drops dropping on different shapes and types of surfaces and the analyzes aren't from the simplest end of the spectrum. Luckily Comsol can hide lots of the underlying physics, how familiar are you with the software?

 

[sparky977]

Hi PerennialII,

thank you for your reply.
I am working with COMSOL for few months.
I did some simulations but in the field of electromagnetics. I simulated some issues in 2D and 3D space, but in descreete values - not complete(real time) simulation like impact of water drop.

Main question for me here is how to define the water level that interacts as water, not as a wall. I know that I have to put some equations somewhere, but I have no idea - yet!- how to.
For start 2D simulation will be also fantastic. ... If everything goes OK, than I will proceed to 3D.

please, I you have some idea ..

 

[PerennialII]

Yeah, getting grips with this without it turning into too complex of a problem seems to be the "clue" of it. Somehow at 1st I get the idea of that would use the ALE technique of Comsol & moving meshes for both the drop & water in the tank. Don't know if it's the simplest way, but could perhaps get a "decent" result of what happens when the drop & pool interact all over the place. 2D most definitely in the beginning. Accurately modeling the interaction and "joining" of the domains is "interesting" depending on how far need to go with it. This would be so much easier using MD .

 

[sparky977]

Md ?

 

[PerennialII]

In a molecular dynamics simulation the interaction is "build-in", while in a continuum simulation have to describe the interaction via continuity, equilibrium etc. equations at the interface during the impact. However with any luck a fairly simple approach can model "the splash" long enough so that can capture details of what is going on (as an extreme a fairly "rigid drop of water" dropping to a pool).