Nodes - Particle Fluids (SPH)

Owned by Anonymous
Last updated: 27 May, 2014 by Anonymous
4 min read

The technology behind our standard particle fluid emitters is called "Smoothed Particle Hydrodynamics", also called SPH. In contrast to RealFlow’s grid fluid emitters, this type is mainly suited for small to mid range simulations. These standard emitters show a very high level of detail, are easy to use and can be affected by any daemon to react with various forces. RealFlow emitters can interact with all kinds of solid or soft bodies and RealWave objects. Another, more advanced feature, is their scripting capability: RealFlow emitters can be completely customized and theoretically it is even possible to write your own fluid engine.

An emitter’s particles can be stored in different file and data formats for further use. The standard format is called "BIN" and stores a complete set of position and physical data. Other formats, such as PD, allow the user to store specific information, for example density or pressure. A very convenient and straightforward method to export particle data comes with the new Alembic format. This file type allows you to export selected data channels, has a hierarchical approach and is supported by many 3D applications. You can find out more about RealFlow’s export options with standard emitters and the Alembic format under “Export Central”. The stored BIN files are normally used to create a polygon mesh inside RealFlow representing the three dimensional volume of the fluid. This mesh finally becomes shaded in your 3D application to render the fluid. Additionally it is also possible to continue processing the particles to create foam or spray.

 

Fluid simulation created by Oyekunle Jegede for "Dancing Diabolo"

 

Particle fluids and fluid meshes can be previewed directly inside RealFlow with the new “Maxwell Interactive” render engine – completely shaded and with specific material properties, e.g. honey or water. This unique feature gives you the possibility to render a photorealistic preview of your fluids, either as a mesh (this option requires a mesh, of course) or as a particle cloud. One of the main advantages is that “Maxwell Interactive” is even capable of adding particles at render time to get a much denser fluid and, as a consequence, a better and more realistic preview. This method is exactly the same you can find in “Maxwell Studio” and the RFRK, there it is called “MultiPoint”. “MultiPoint” has a procedural approach to add millions of particles in a very short time. The result is an absolutely realistic impression of spray or misty particle clouds. Please bear in mind that these extra particles are not stored, but only temporarily created. After the render process, the “MultiPoint” particles are lost. This guarantees that the original fluid simulation will not be modified.

If you are working with Pixar’s RenderMan, mentalray, Houdini's Mantra or compliant render engines then you should consider using the RealFlow RenderKit (RFRK). Its advanced meshing and particle options are the perfect addition for processing huge meshes or large particle amounts in production environments. For more information please visit the RFRK section on the RealFlow website or contact Next Limit is sales desk.

RealFlow emitters are incredibly flexible. They are not just particle sources, but also used to create splashes from interactions with RealWave and rigid bodies, calculate the behaviour of gaseous fluids, or produce millions of ultra-fast dumb particles to mimic spray, for example. With adequate Python scripts or C++ plugins it is also possible to simulate other natural phenomena, like fire, explosions or swirling smoke. Daemons and forces are added to shape fluids to your specific needs. You can even use animated objects and characters to emit particles from their surface or fill an object completely or partially with particles. With a so-called “Binary Loader” or “NBinary Loader” you can even re-time, combine and manipulate already simulated particles.

As well as offering many versatile applications, RealFlow emitters are both fast and very accurate. Especially interactions with particles from other emitters or solid objects are easy to use and it only takes a few mouse clicks to establish a connection. On the other hand you can create all kinds of combinations to make emitters, forces or objects exclusive to selected nodes. RealFlow’s particle interaction settings help you to refine a fluid’s behaviour in combination with solid objects.

Emitters can be added easily from various sources:

Edit > Add > Emitter > Choose the appropriate type

Icon Bar > Emitter > Choose the appropriate type

Right-click menu > Add > Emitter > Choose the appropriate type

Relationship Editor > Tab key > Choose the appropriate type from the “Emitter” entry


Regardless of the method you use, you will always find a set of 14 emitter types for any field of application. Of course, RealFlow standard emitter nodes are also supported by the “Relationship Editor”. In RealFlow 2013, this editor has substituted the “Global Links” and “Exclusive Links” panels and now you can establish all interactions visually with node icons and connections between them.

Particle Fluid Emitters (SPH) - Tutorials

  • Leaking Objects
  • Calm Fluid Surfaces
  • How to Stop an Emitter From Creating Particles?
  • Foam with SPH Particles
  • How to Create Wetmaps
  • Scripted Splashes