voidfractionModel_IBVoidFraction command
Syntax
Defined in couplingProperties dictionary.
voidfractionModel IB;
IBProps
{
maxCellsPerParticle number1;
alphaMin number2;
scaleUpVol number3;
checkPeriodicCells ;
}
number1 = maximum number of cells covered by a particle (search will fail when more than number1 cells are covered by the particle)
number2 = (optional, default 0.1) minimum limit for voidfraction
number3 = diameter of the particle’s representation is artificially increased according to number3 * Vparticle, volume remains unaltered!
checkPeriodicCells = (optional, default false) flag for considering the minimal distance to all periodic images of this particle
Examples
voidfractionModel IB;
IBProps
{
maxCellsPerParticle 1000;
alphaMin 0.10;
scaleUpVol 5.0;
}
Description
The IB voidFraction model is supposed to be used when a particle (or its representation) is bigger than a CFD cell. The voidfraction field is set in those cell whose centres are inside the particle. The model is specially designed for cfdemSolverIB and creates a smooth transition of the voidfraction at the particle surface. Cells which are only partially covered by solid are marked by voidfraction values between 0 and 1 respectively.
The region of influence of a particle can be increased artificially by “scaleUpVol”, which blows up the particles, but keeps their volume (for voidfraction calculation) constant.
Code of this sub-model contributed by Alice Hager, JKU.
Restrictions
none.