# Is it possible to create a fluid simulation of rain?

Is it possible to simulate rain with the fluid simulator?

I tried to do something with a bunch of Inflow cubes that get enabled and disabled, however this is very tedious. Is there a better way?

I realize that using a fluid simulation is probably overkill, I'm attempting this as a test. I should also note that I only want this for the simulation of the impact of the droplets on a hard surface, so I only need to simulate ~50 or so droplets.

• I really wouldn't recommend this, even if you have tons of ram. Particles and dynamic paint are a much better alternative. – iKlsR Nov 17 '13 at 0:44
• WOW. Why do you want fluid for rain ? Is it for testing purpose ? Instead you can use "fluid" type of particle's physics... – Polosson Nov 17 '13 at 0:45
• The main reason is because I want to have it collide with a mesh and run down the sides etc. (The whole thing is a test) – gandalf3 Nov 17 '13 at 0:48
• @gandalf3 Particles can collide, you could probably fake the rest with dynamic paint and animated droplets etc.. not sure if Blender supports wetmaps either? – iKlsR Nov 17 '13 at 0:52
• @iKlsR Well, I know they can collide, but I mean collide with realistic splashing, splattering and spraying? I am trying this a test anyway, so I'm not really looking for the most efficient way to do it (though that would be good to know too..) – gandalf3 Nov 17 '13 at 2:30

You can try the Fluid physics type in a particle emitter :

• Add a particle system to a plane and configure it the way you want (number, start, max age...)
• In the Physics panel, select Fluid.
• Select the object you want the particles to run down on
• Add a Collision physics modifier to this object (make sure it has enough faces), with particle damping Factor set to 1
• hit play and:

Next, you just have to create a nice shader (this one is a blueish transparent shader, just for demonstration, very bad)

However, this type of simulation is not very realistic and some tweaks may be needed to suit your needs. It's just a track...

• Thanks for your answer, though I take it there is no way to mesh these into a single solid object instead of a lot of spheres? – gandalf3 Nov 17 '13 at 2:28
• This would be great, indeed... But I don't know how. Metaball instance for particles, maybe ? – Polosson Nov 17 '13 at 15:11
• Protip: metaball instance for particles (if you can get it to work; I've done it in the past but it's tricky and unpredictable) is an excellent way to melt your CPU. Once you start getting into the hundreds it'll take a long time to orbit the scene, much less render. – wchargin Nov 17 '13 at 17:17