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Public Member Functions

basic Class Reference

Basic sub-grid obstacle drag model. Details supplied by J Puttock 2/7/06. More...

Detailed Description

Basic sub-grid obstacle drag model. Details supplied by J Puttock 2/7/06.

Sub-grid drag term

The resistance term (force per unit of volume) is given by:

\[ R = -\frac{1}{2} \rho \vert \dwea{\vec{U}} \vert \dwea{\vec{U}}.D \]

where:

$ D $ is the tensor field "CR" in $ m^{-1} $

This is term is treated implicitly in UEqn.H

Sub-grid turbulence generation

The turbulence source term $ G_{R} $ occurring in the $ \kappa-\epsilon $ equations for the generation of turbulence due to interaction with unresolved obstacles :

$ G_{R} = C_{s}\beta_{\nu} \mu_{eff} A_{w}^{2}(\dwea{\vec{U}}-\dwea{\vec{U}_{s}})^2 + \frac{1}{2} \rho \vert \dwea{\vec{U}} \vert \dwea{\vec{U}}.T.\dwea{\vec{U}} $

where:

$ C_{s} $ = 1

$ \beta_{\nu} $ is the volume porosity (file "betav").

$ \mu_{eff} $ is the effective viscosity.

$ A_{w}^{2}$ is the obstacle surface area per unit of volume (file "Aw").

$ \dwea{\vec{U}_{s}} $ is the slip velocity and is considered $ \frac{1}{2}. \dwea{\vec{U}} $.

$ T $ is a tensor in the file CT.

The term $ G_{R} $ is treated explicitly in the $ \kappa-\epsilon $ Eqs in the PDRkEpsilon.C file.

Source files

Definition at line 96 of file basic.H.

Inheritance diagram for basic:
Collaboration diagram for basic:

List of all members.

Public Member Functions

 TypeName ("basic")
 Runtime type information.
 basic (const dictionary &PDRProperties, const compressible::RASModel &turbulence, const volScalarField &rho, const volVectorField &U, const surfaceScalarField &phi)
 Construct from components.
virtual  ~basic ()
virtual tmp< volSymmTensorField >  Dcu () const
 Return the momentum drag coefficient.
virtual tmp< volScalarField >  Gk () const
 Return the momentum drag turbulence generation rate.
virtual bool  read (const dictionary &PDRProperties)
 Update properties from given dictionary.

Constructor & Destructor Documentation

basic ( const dictionary &   PDRProperties,
const compressible::RASModel &   turbulence,
const volScalarField &   rho,
const volVectorField &   U,
const surfaceScalarField &   phi  
)

Construct from components.

virtual ~basic (  ) [virtual]

Member Function Documentation

TypeName ( "basic"    )

Runtime type information.

virtual tmp<volSymmTensorField> Dcu (  ) const [virtual]

Return the momentum drag coefficient.

Implements PDRDragModel.

virtual tmp<volScalarField> Gk (  ) const [virtual]

Return the momentum drag turbulence generation rate.

Implements PDRDragModel.

virtual bool read ( const dictionary &   PDRProperties  ) [virtual]

Update properties from given dictionary.

Implements PDRDragModel.

The documentation for this class was generated from the following file:
  • applications/solvers/combustion/PDRFoam/PDRModels/dragModels/basic/basic.H