Simulation Options: Dyverso

Owned by thomas (Unlicensed)
Last updated: 24 Nov, 2015
3 min read

RealFlow's scene-related simulation options are located here:




To change the parameters of this tab on a global level use the → "Preferences - Simulation: Dyverso" dialogue.



Global (A)

Time scale

Values smaller than 1.0 will decelerate the fluid; settings greater than 1.0 have an acceleration effect. “Time scale” works as a factor: 2.0 means that the fluid will be two times faster.

Stepping Strictness

RealFlow calculates how fast the fluid will move within a → substep:

  • With a value of 1.0, the fluid will not move more than 1 grid cell in the current time step.
  • With values smaller than 1.0, the fluid can cover a longer distance within a single step – the solver is less strict.
Use Geometry Velocity

When enabled RealFlow will adjust the simulation's → substeps to get a correct fluid-object interaction behaviour:

  • Imagine an object falling into a container with → calm water.

  • Here, RealFlow uses very large substeps to speed up the simulation.

  • Due to these large steps the interaction between the object and the fluid is delayed.

  • With “Use Geometry Velocity” the interaction will happen in time again.

PBD Solver (B)

MIN substeps

Specify the minimum number of simulation steps for → Dyverso PBD fluids:

  • Higher values increase simulation time and can lead to instabilities with PBD fluids. We recommend moderate increases of just a few substeps.
  • For a fixed number of substeps use equal values for “MIN substeps” and “MAX substeps”.
  • The default value normally provides the best ratio between speed and accuracy.
MAX substeps

Specify the maximum number of simulation steps for → Dyverso PBD fluids:

  • Higher values increase simulation time and can lead to instabilities with PDB fluids. Try using values around the default setting.
  • For a fixed number of substeps use equal values for “MIN substeps” and “MAX substeps”.
  • The default value normally provides the best ratio between speed and accuracy.
MIN iterations

Specify the minimum number of simulation cycles for → Dyverso PBD fluids:

  • Higher values increase simulation time, but also avoid instabilities.
  • For a fixed number of iterations use equal values for “MIN iterations” and “MAX iterations”.
MAX iterations

Specify the maximum number of simulation cycles for → Dyverso PDB fluids:

  • Higher values increase simulation time, but also avoid instabilities.
  • For a fixed number of iterations use equal values for “MIN iterations” and “MAX iterations”. 
Accuracy

This parameter ranges between 0.0 and 1.0. With

  • 0.0 RealFlow quickly finds a solution, but it will not be very accurate
  • 1.0 RealFlow finds a solution that is very close to the exact behaviour, but simulation time will increase.

Liquid - SPH Solver (C)

MIN substeps

Specify the minimum number of simulation steps for → Dyverso SPH fluid type:

  • Higher values increase simulation time, but also avoid instabilities.
  • For a fixed number of substeps use equal values for “MIN substeps” and “MAX substeps”.
MAX substeps

Specify the maximum number of simulation steps for → Dyverso SPH fluid type:

  • Higher values increase simulation time, but also avoid instabilities.
  • For a fixed number of substeps use equal values for “MIN substeps” and “MAX substeps”.

OpenCL (D)

Due to the almost infinite number of hardware combinations we cannot guarantee that RealFlow's OpenCL features are available for any computer or graphic device. Please read the → FAQ - Dyverso & GPUs chapter if you encounter performance issues.

Use OpenCL-CPU

This option is only available if your computer supports OpenGL-CPU calculations.

Use OpenCL-GPU

You can activate this option if your graphics card has OpenCL capability, otherwise it is greyed out.

Use OpenCL-Accelerator

This function is only available with dedicated OpenCL-acceleration hardware. These devices have to be purchased separately.

System Information...

Open a comprehensive summary about your GPU's features and capabilities.

Select GPU...

Got more than one GPU in your computer? Choose here which board you want to use with your Dyverso simulation.

CUDA (E)

Please read the → FAQ - Dyverso & GPUs chapter if you encounter performance issues.

Use OpenCL-CUDA
You can activate this option if your graphics card has CUDA capability, otherwise it is greyed out.
CUDA Information...

Open a comprehensive summary about your GPU's CUDA features and capabilities.

Select CUDA GPU...

Got more than one CUDA GPU in your computer? Choose here which board you want to use with your Dyverso simulations.