Help with Fluid Sim

Hello all,

I’m extremely green with blender fluid simulation and I need some help for a project. I have modeled a sink and I need a drop of water to fall from it. I want the drop to fall in slow motion so that my camera can track it for about 35 seconds. In that 35 seconds, I want the lighting to be able to change and the droplet will appear to be falling through black nothingness with colored lights flying by it (like Alice falling down the rabbit hole). I can handle all the lighting issues, but what I’m having trouble with is the fluid sim. I don’t know what settings to tweak and what to do to make it appear like a dropplet of water (real-world size issues/grid-size issues/resolution/timing). I have a timeline of 1000 frames at 25fps so that I can cut out the bit that I need. Can anybody please help me figure this out? If you need the file or any more info about the project let me know and I’ll do what I can.

Thanks in advance

Try a real world size that a drop would be in the real world
Try different resolution figures, the default is extremely low. Set the display quality from Preview to Final. Note that you may need to change the fluid viscosity as the droplet may deform in shape as it drops rather that staying as a sphere. Give it a suitable material to look like water.
Say you want to simulate a drop falling 50cm, in the real world this would take approx 0.3secs so that would be the value you put as the Time:End setting
0.3 secs over say 1000 frames at 25fps animation means you’d be running your simulating of 0.3secs over an animation lasting 40 secs which is 1/133 real world speed
Wiki article on fluid sim

Hi there, i’ve been trying a few different fluid settings myself recently, i would recommend to use an inflow object for the droplet, and animate it to activate on the frame you would like the droplet to start falling, then add a keyframe to deactivate it on the next frame.

For the water’s material which is in effect the domain material, make sure you set it to raytracing transparency and then set the IOR value to 1.33, this will bend/refract/slow the light through the droplet to give it that watery look.

I agree with Richard, you may need to experiment with the viscosity and domain size in order to get the effect of the type of droplet you’re after.

Hope this gets you going in the right direction! :slight_smile: