KriegerDoughertyViscosity

Syntax

Defined in transportProperties dictionary.

viscosityModel KriegerDoughertyViscosity;

KriegerDoughertyViscosityCoeffs
{
    nu0             nu0   [ 0 2 -1 0 0 0 0 ] scalar;
    nuMax           nuMax [ 0 2 -1 0 0 0 0 ] scalar;
    nuBar           nuBar [ 0 0  0 0 0 0 0 ] scalar;
    voidfractionMin voidfractionMin [ 0 0 0 0 0 0 0 ] scalar;
}

  • nu0 = reference viscosity

  • nuMax = XXX

  • nuBar = intrinsic viscosity

  • voidFractionMin = the maximum particle voume fraction in terms of the particle voidfraction, i.e. \varepsilon_\mathrm{p,m}

Examples

KriegerDoughertyViscosityCoeffs
{
    nu0             nu0   [ 0 2 -1 0 0 0 0 ] 1e-5;
    nuMax           nuMax [ 0 2 -1 0 0 0 0 ] 1e-01;
    nuBar           nuBar [ 0 0  0 0 0 0 0 ] 2.5;
    voidfractionMin voidfractionMin [ 0 0 0 0 0 0 0 ] 0.35;
}

Description

Calculates the viscosity according to the equation

\frac{\eta}{\eta_0} = \left( 1 - \frac{\varepsilon_\mathrm{p}}{\varepsilon_\mathrm{p,m}} \right)^{-\eta_\mathrm{Bar} \varepsilon_\mathrm{p,m}} \quad ,

where \eta_0 is the reference viscosity, \varepsilon_\mathrm{p} the particle volume fraction, \varepsilon_\mathrm{p,m} the maximal particle volume fraction (0.64 for monodisperse spheres) and \eta_\mathrm{Bar} the intrinsic viscosity (2.5 for spheres). The model is suitable for concentrated suspensions.

Restrictions

None.