This class corresponds to the viscous part of the "natural" boundary condition for the momentum equations, i.e. More...

#include <NSMomentumViscousBC.h>

Inheritance diagram for NSMomentumViscousBC:

Public Member Functions
	NSMomentumViscousBC (const InputParameters &parameters)

Protected Member Functions
virtual Real	computeQpResidual ()
	Just like other kernels, we must overload the Residual and Jacobian contributions... More...

virtual Real	computeQpJacobian ()

virtual Real	computeQpOffDiagJacobian (unsigned jvar)

bool	isNSVariable (unsigned var)

unsigned	mapVarNumber (unsigned var)

Protected Attributes
const unsigned	_component

NSViscStressTensorDerivs< NSMomentumViscousBC >	_vst_derivs

const VariableValue &	_u_vel

const VariableValue &	_v_vel

const VariableValue &	_w_vel

const VariableValue &	_rho

const VariableValue &	_rho_u

const VariableValue &	_rho_v

const VariableValue &	_rho_w

const VariableValue &	_rho_E

const VariableGradient &	_grad_rho

const VariableGradient &	_grad_rho_u

const VariableGradient &	_grad_rho_v

const VariableGradient &	_grad_rho_w

const VariableGradient &	_grad_rho_E

unsigned	_rho_var_number

unsigned	_rhou_var_number

unsigned	_rhov_var_number

unsigned	_rhow_var_number

unsigned	_rhoE_var_number

const MaterialProperty< Real > &	_dynamic_viscosity

const MaterialProperty< RealTensorValue > &	_viscous_stress_tensor

const IdealGasFluidProperties &	_fp

Friends
template<class U >
class	NSViscStressTensorDerivs

Detailed Description

This class corresponds to the viscous part of the "natural" boundary condition for the momentum equations, i.e.

int_{Gamma} n . (-tau) . v

A typical use for this kernel would be a subsonic outflow BC in which one physical value must be specified. In this case, the residual and Jacobian contrbutions of the n.tau.v term is computed and added to the matrix/rhs.

Definition at line 32 of file NSMomentumViscousBC.h.

Constructor & Destructor Documentation

◆ NSMomentumViscousBC()

NSMomentumViscousBC::NSMomentumViscousBC ( const InputParameters & parameters )

Definition at line 26 of file NSMomentumViscousBC.C.

   : NSIntegratedBC(parameters),
     _component(getParam<unsigned>("component")),
     // Derivative computing object
     _vst_derivs(*this)
 {
 }

Member Function Documentation

◆ computeQpJacobian()

Real NSMomentumViscousBC::computeQpJacobian ( )

protectedvirtual

Definition at line 51 of file NSMomentumViscousBC.C.

 {
   // See Eqns. (41)--(43) from the notes for the viscous boundary term contributions
   Real visc_term = 0.0;
  
   // Set variable names as in the notes
   const unsigned int k = _component;
   const unsigned int m = _component + 1; // _component = 0,1,2 -> m = 1,2,3 global variable number
  
   // FIXME: attempt calling shared dtau function
   for (unsigned int ell = 0; ell < LIBMESH_DIM; ++ell)
     visc_term += _vst_derivs.dtau(k, ell, m) * _normals[_qp](ell);
  
   // Multiply visc_term by test function
   visc_term *= _test[_i][_qp];
  
   // Note the sign...
   return -visc_term;
 }

◆ computeQpOffDiagJacobian()

Real NSMomentumViscousBC::computeQpOffDiagJacobian ( unsigned jvar )

protectedvirtual

Definition at line 72 of file NSMomentumViscousBC.C.

 {
   if (isNSVariable(jvar))
   {
  
     // See Eqns. (41)--(43) from the notes for the viscous boundary
     // term contributions.
  
     // Map jvar into the variable m for our problem, regardless of
     // how Moose has numbered things.
     unsigned m = mapVarNumber(jvar);
  
     // Now compute viscous contribution
     Real visc_term = 0.0;
  
     // Set variable names as in the notes
     const unsigned int k = _component;
  
     for (unsigned int ell = 0; ell < LIBMESH_DIM; ++ell)
       visc_term += _vst_derivs.dtau(k, ell, m) * _normals[_qp](ell);
  
     // Multiply visc_term by test function
     visc_term *= _test[_i][_qp];
  
     // Note the sign...
     return -visc_term;
   }
   else
     return 0.0;
 }

◆ computeQpResidual()

Real NSMomentumViscousBC::computeQpResidual ( )

protectedvirtual

Just like other kernels, we must overload the Residual and Jacobian contributions...

Definition at line 35 of file NSMomentumViscousBC.C.

 {
   // n . (-tau) . v
  
   // Vector-valued test function
   RealVectorValue v_test;
   v_test(_component) = _test[_i][_qp];
  
   // The viscous contribution: n . tau . v
   Real visc_term = _normals[_qp] * (_viscous_stress_tensor[_qp] * v_test);
  
   // Note the sign...
   return -visc_term;
 }

◆ isNSVariable()

bool NSIntegratedBC::isNSVariable ( unsigned var )

protectedinherited

Definition at line 80 of file NSIntegratedBC.C.

 {
   if (var == _rho_var_number || var == _rhou_var_number || var == _rhov_var_number ||
       var == _rhow_var_number || var == _rhoE_var_number)
     return true;
   else
     return false;
 }

◆ mapVarNumber()

unsigned NSIntegratedBC::mapVarNumber ( unsigned var )

protectedinherited

Definition at line 90 of file NSIntegratedBC.C.

 {
   // Convert the Moose numbering to:
   // 0 for rho
   // 1 for rho*u
   // 2 for rho*v
   // 3 for rho*w
   // 4 for rho*e
   // regardless of the problem dimension, etc.
   unsigned int mapped_var_number;
  
   if (var == _rho_var_number)
     mapped_var_number = 0;
   else if (var == _rhou_var_number)
     mapped_var_number = 1;
   else if (var == _rhov_var_number)
     mapped_var_number = 2;
   else if (var == _rhow_var_number)
     mapped_var_number = 3;
   else if (var == _rhoE_var_number)
     mapped_var_number = 4;
   else
     mooseError("Invalid var!");
  
   return mapped_var_number;
 }