dividedVoidFractionSuperquadric

Syntax

Warning

THIS MODEL IS NO LONGER USED - check the documentation in divided.

Defined in couplingProperties dictionary.

particleShapeType superquadric;
voidfractionModel divided;
dividedProps
{
    alphaMin number1;
    interpolation;
    volScale number2;
    porosity number3;
}

  • number1 = (optional, default 0.3) minimum limit for voidfraction

  • interpolation = (optional, default false) flag to interpolate voidfraction to particle positions

  • number2 = (optional, default 1) scaling (per type) of the particle volume to account for porosity or agglomerations.

  • number3 = (optional) diameter of the particle’s representation is artificially increased according to number2 * Vparticle, volume remains unaltered!

Examples

particleShapeType superquadric;
voidfractionModel divided;
dividedProps
{
    alphaMin 0.2;
    volScale ( 1. );
}

Description

The divided voidFraction model is supposed to be used when a particle (or its representation) is in the size range of a CFD cell. Satellite points are used to divide the particle’s volume to the touched cells.

The region of influence of a particle can be increased artificially by “porosity”, which blows up the particles, but keeps their volume (for voidfraction calculation) constant.

The particle volume occupied in the CFD domain can be adjusted by the parameter “volScale”, using Vparticle:=Vparticle*volScale.

In the basic implementation of solvers, the void fraction is calculated based on all particles. Depending on the solver used, the void fraction calculation is also performed for a certain type of particles. The void fraction calculation is based on a three-step approach (reset, set and interpolate), i.e., the void fraction is time interpolated from a previous and a next void fraction field. Appropriate names for these fields have to be specified in the sub-dictionaries voidFracFieldNamesPrev and voidFracFieldNamesNext in the couplingProperties dictionary.

This is a variant of the dividedVoidFractionModel optimized for superquadric particles. It is automatically loaded when the superquadric particle shape is selected.

Code of this sub-model contributed by Alexander Podlozhnyuk, DCS Computing GmbH.

Note

This model requires the particle to be set to superquadric AND a force model which uses this shape type.

Restrictions

Only for superquadric particles. Automatically loaded for this particle shape.