Fluids

I've never worked with fluids before so it took me a while to wrap my head around fluids and the different types inside Houdini. It was also hard finding good intro videos out there for fluids.

Basically there's 3 kinds of fluids:

1. Volume Fluids - needs to know dops
2. Particle Fluids - needs to know pops
3. Flip Fluids - needs to know both

I wasn't really sure which one to use and I knew I had to break up my tunnel into several pieces, because otherwise it would just take forever to render.  So this is how I broke it down:

My fluid tests for the first section of my tunnel: click here

Volume Fluids

I learned very early that it's not easy getting fluids to sit still especially for Particle and Flip fluids so for the first section of my project I'm using volume fluids.  With volume fluids you're basically working inside a liquid container which is filled with voxels or an SDF field (this is how I understood it).  When you place a liquid object inside the container an SDF field is built for that object and the two fields will interact with one another to get a liquid surface (dops).

When you create a volume fluid make sure you check out the details view for the AutoDopNetwork.  There's lots of useful data that's generated with the fluid that you can use to drive other things elsewhere:

This one comes in by default so you can see what your liquid surface looks like.

This is the SDF field which can be used for fog.

These are the surfel points which can be used in a popnet.

This is the velocity field which can be adjusted with VOP for some vectors.

  

Here are some helpful links: Peter Quint's Volumes, cmiVFX's Fluid Effects for TD's.

*check back for Particle and Flip fluids

Download: Houdini Ocean otl / Tutorial: Houdini Hip Tricks Volume 2

Other makers of fluid effects: RealFlow, Exotic Matter's Naiad