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This page introduces the Simulator object and its rollouts.


The PhoenixFD Simulator object produces realistic fire/smoke/explosion and liquid effects using physical simulation.

For fire, smoke, and explosion simulations, PhoenixFD Simulator uses a grid-based core, and the result is a sequence of cache files containing the frame data (Temperature, Smoke, etc). These cache files are used later in the rendering process to convert the raw simulation data into realistic images.

Liquid simulations use the FLIP solver since Phoenix 3.0. Compared to the grid-based solution in Phoenix 2, FLIP provides the following:

  • More realistic simulation
  • No stepping artifacts
  • Faster simulation

Besides liquid, the simulator provides built-in helper simulators for foam, wetmap, splash, and mist. In certain cases, the splash and mist can be considered as part of the liquid simulation, because liquid, splash and mist can be converted to each other. You can go through the FLIP Particles Life Cycle page for an in-depth explanation of this process.

The simulator is represented as single object for user's convenience. Internally, it contains two completely separate parts: a simulator component and a rendering component. Parameters that control the simulator component are separated from those associated with the rendering component. As a result, no rollout will contain mixed parameters, and no parameter will affect both the simulation and rendering.

In addition to manual creation of a simulator with the UI paths shown below, a simulator is automatically created when any of the Quick Simulation Setup buttons are used.

Note: In addition to a simulator, a Source Component must also be present in the scene in order for simulation to take place.



 UI Paths:

||Phoenix FD menu|| > Create > 3D Simulator

||Phoenix FD Shelf|| > Create Phoenix FD 3D Fluid Simulator button


||Phoenix FD Shelf|| > Create Phoenix FD 2D Fluid Simulator button





After creating a PhoenixFD Simulator object, the following rollouts can be accessed in the Attribute Editor:

  • Simulation - Controls the simulation and displays statistical information.
  • Resimulation - Uses a simulated cache sequence with exported velocity to drive a new simulation. Capable of adding time effects, increasing the resolution, etc. For liquid simulations, modifies an existing cache sequence to improve features or change specified particle systems.
  • Grid - Controls the size and resolution of the simulation grid.
  • Dynamics - Controls fire dynamics such as cooling, smoke dissipation, vorticity, advection, etc.
  • Fuel - Controls the burning simulation for special effects such as gasoline explosions.
  • Liquid - Controls liquid dynamics such as viscosity, surface tension, drying time, etc.
  • Foam - Controls bubbles and foam.
  • Splash and Mist - Controls splash and mist simulation.
  • Output - Specifies how the simulation cache files are saved.
  • Input - Determines the path of input files for rendering and previewing.
  • Scene Interaction - Specifies how the simulator interacts with other objects in the scene.
  • Preview - Controls how the simulation is displayed in the viewport.
  • Rendering - Controls how the simulation is rendered and includes additional volumetric options.


Simulation in 2D

The Phoenix simulator has the ability to perform a 2D simulation if one of the grid dimensions is set to 1. The main application of this feature is to create very wide fires that would otherwise be difficult with 3D simulation. See the Grid rollout for more information.


Upgrading from Previous Versions of Phoenix FD

Due to many improvements to the Phoenix solver, recreating simulations the same way you did in older versions of Phoenix may not be possible because of changes to the solvers and the UI. Here are some things to be aware of when upgrading from older versions of Phoenix FD.

  • If you have a scene created with Phoenix v.2 and you open it with version 3, it will keep all the old settings for you, some of which are not visible to newer versions and the result should be roughly the same.
  • If you try to replicate the same simulation setup with Phoenix v.3 and set all the parameters with the same values you would not obtain the same result. The new simulation will be different because Phoenix v.3 uses a new solver for liquids and fire/smoke.