forceModel BeetstraDrag command

Syntax

Defined in couplingProperties dictionary.

forceModels
(
    BeetstraDrag
);
BeetstraDragProps
{
    velFieldName          "U";
    voidfractionFieldName "voidfraction";
    minVoidfraction       scalar1;
    granVelFieldName      "Us";
    useFilteredDragModel;
    g                     gravity;
    dPrim                 dPrimValue;
    rhoP                  rhoPValue;
    rho                   rhoValue;
    nuf                   nufValue;
    useParcelSizeDependentFilteredDrag;
    k                     kValue;
    treatForceExplicit;
    implForceDEM;
    verbose;
    interpolation;
}

  • U = name of the finite volume fluid velocity field

  • voidfraction = name of the finite volume void fraction field

  • minVoidfraction = minimum void fraction value to ensure meaningful interpolated void fraction (default = 0.1)

  • Us = name of the finite volume cell averaged particle velocity field

  • useFilteredDragModel = switch for using a coarsening correction for the Beetstra drag model (takes grid-size effects into account; default = off)

  • gravity = gravity value (default = 9.81)

  • dPrimValue = diameter of primary particle

  • rhoPValue = particle density

  • rhoValue = finite volume density

  • nufValue = kinematic viscosity

  • useParcelSizeDependentFilteredDrag = switch for using a coarsening correction for the Beetstra drag model (only used if useFilteredDragModel is on; default = off)

  • kValue = factor for parcels size effect (default = 0.05; must be defined if useParcelSizeDependentFilteredDrag is used)

  • interpolation = flag to use interpolated void fraction and fluid velocity values (normally off)

  • treatForceExplicit = switch to force explicit treatment of force (normally off)

  • implForceDEM = flag to use implicit formulation of drag on DEM side (normally off, if on, this switch will force treatForceExplicit to be off)

  • verbose = switch to force display of data on screen (default: off; typically used for debug purposes)

Examples

forceModels
(
    BeetstraDrag
);
BeetstraDragProps
{
    velFieldName          "U";
    voidfractionFieldName "voidfraction";
    granVelFieldName      "Us";
    interpolation true;
    useFilteredDragModel;
    g       9.81;
    dPrim   100e-6;
    rhoP    7000.;
    rho     10.;
    nuf     1.5e-4;
    useParcelSizeDependentFilteredDrag;
    k       0.05;
}

Description

The force model performs the calculation of forces (e.g. fluid-particle interaction forces) acting on each DEM particle. The BeetstraDrag model is a model that calculates the particle based drag force following the correlation of Beetstra et al. (2007). The filtered drag model is based on Radl and Sundaresan (2014).

Restrictions

This model is strictly valid only for monodisperse gas-particle flows. For the polydisperse model of Beetstra et al. (2007) use BeetstraDragPoly.