Hi,

I wanted to know how you would create a custom velocity field ,
which will help me to get more variation on my simulation

Thanks

“Field Force” node can help you I guess …

you can also use a sop solver plugged into 3rd tab on the flip solver and object merge your volume into it ad add it to the vel field either with a volume mix or by first adding it to a temp vel field and using a gas calculate / gas linear combination / gas field vop to add this temp field to the vel field.

to make this process easier you can use a source volume dop which sets up a more thorough version of this for you. if you set it to source pump, it will be similar to sourcing a vel field, the only difference being that it is masked by a scalar pump field.

Hey Zachary,

I am stuck a problem I think you can solve.
I am using source volume to get vel field to a flip to create a ocean.
I use ocean tools provided by houdini for that.
But I need a specific wave bigger than the others.
I used a fieldforce dop with a sopogeo dop for that but nothing happen.
Do you know why ?

Maybe the solution is to create a new source volume mixing the field from the ocean evaluate sop and a field create from the mesh I am actually using for the field force. But I have no idea how to create vel volume from a simple deformed plane … And I don't know if I have to mix the vel volumes in sop level or in dop …

Thanks for your help.

instead of a sop geo dop, use a sop vector field dop. also, where you are using the field force in your network?

if you are using it just as a force on your object, it may be getting cleared out by the solver (not sure on this). if you want to add the field force to the points in the sim, you should do that in the 2nd tab of the solver. if you want to use it on the grid, then you need to plug it into the 3rd tab. if thats the case though i would just use a source volume instead, or use a gas calculate / gas linear combination to add the incoming sop vector field to the vel of the sim.

I plugged my sopgeo/field force after the flipsolver.
similar to the field force example in the doc.

did you try switching the sop geo with a sop vector field? can you post a small example of it not working?

ok
after a recheck I found I unchecked “Ignore Particle Mass for Forces” option

arghh !

anyway …

Wow so much happened on my post

Hi zdimaria,

Can you please share a basic houdini file ,as am really new to houdini

Thanks