The JohnsonJacksonParticleTheta is a boundary condition that provides Robin condition for the particulate granular temperature.


Reuge, N., Cadoret, L., Coufort-Saudejaud, C.,
Pannala, S., Syamlal, M., & Caussat, B. (2008).
Multifluid Eulerian modeling of dense gas–solids fluidized bed
hydrodynamics: influence of the dissipation parameters.
Chemical Engineering Science, 63(22), 5540-5551.

Johnson, P. C., & Jackson, R. (1987).
Frictional–collisional constitutive relations for granular materials,
with application to plane shearing.


The condition requires entries in both the boundary and field files.

Boundary file

    type            patch;

Field file

    // Mandatory entries
    type            JohnsonJacksonParticleTheta;
    specularityCoefficient  <dimensionedScalar>;
    restitutionCoefficient  <dimensionedScalar>;

    // Inherited entries


Property Description Type Required Default
type Type name: JohnsonJacksonParticleTheta word yes -
specularityCoefficient Specularity coefficient [-] dimensionedScalar yes -
restitutionCoefficient Restitution coefficient [-] dimensionedScalar yes -

The inherited entries are elaborated in:

  • mixedFvPatchFields.H

  • The specularity coefficient has to be within (0, 1).
  • The restitution coefficient has to be within (0, 1).

Further information


Source code:



  • Introduced in version v2012