FunkySetfields +InterFOAM
 

Hi all,

I have been using funky setfeilds+interfoam to simulate droplet impingement on to a free surface. I create a circular gamma field using funkySetfields. As I run my simulation, the droplet impacts the free surface vertically. How do I modify so that the droplet impinges the free surface obliquely?I tried changing the acceleration due to gravity by multiplying it with pi/4, rotated the mesh by pi/4 etc but nothing worked. Any help would be appreciated

Cheers,

Ramesh

I think the correct physics is to give bubble an initial horizontal velocity. Changing the direction of gravity will obviously also change the orientation of your free surface, which is probably not what you want.

Thanks Bernhard. How do I do this?.

Did you try funkySetFields?

Yes, I use the following commands
funkySetFields -time 0 -field U -expression 'vector(0,0,0)' -keepPatches
funkySetFields -time 0 -field gamma -expression 0 -keepPatches
funkySetFields -time 0 -field gamma -expression 1 -keepPatches -condition "pow(pos().x-0.292,2)+pow(pos().y-0.534,2)<pow(0.05,2)"
funkySetFields -time 0 -field gamma -expression 1 -keepPatches -condition "pos().x <=0.584 && pos().y <=0.05"
attached are two picture. Initial shows the intial gamma field created using funkySetfields using the above commands.
If my velocity vector is (0,0,0) the droplet falls vertically.

I changed the velocity vector (0.71, 0,0). Although it starts to impact obliquely(02sec_field.jpg) , the problem I have is even the liquid layer at the bottom also changes. Please let me know how to fix this

Of course only set the initial velocity inside the bubble, with the same expression you used to set the gamma-field.

Thanks. How do I set the velocity only inside the bubble?

By using what you already know from funkySetFields? If you can set gamma inside your bubble, you can probably do it for U as well, right?

Thanks for your help. It worked..

Hi,

suppose I replace this liquid droplet with a solid object How do I go about solving this type of problem. Ofcourse, this solid object is in air and there is a layer of liquid at the bottom

Then your situation is completely different. You cannot use interFoam, and I don't know whether it is possible in OpenFOAM to solve this kind of problem. At least you have to deal with dynamic meshes and stuff like that.