Ejemplo n.º 1
0
  void AveragedTurbine<Mu>::nonlocal_time_derivative(bool compute_jacobian,
				                 AssemblyContext& context,
				                 CachedValues& /* cache */ )
  {
    libMesh::DenseSubMatrix<libMesh::Number> &Kss =
            context.get_elem_jacobian(this->fan_speed_var(), this->fan_speed_var()); // R_{s},{s}

    libMesh::DenseSubVector<libMesh::Number> &Fs =
            context.get_elem_residual(this->fan_speed_var()); // R_{s}

    const std::vector<libMesh::dof_id_type>& dof_indices =
      context.get_dof_indices(this->fan_speed_var());

    const libMesh::Number fan_speed =
      context.get_system().current_solution(dof_indices[0]);

    const libMesh::Number output_torque =
      this->torque_function(libMesh::Point(0), fan_speed);

    Fs(0) += output_torque;

    if (compute_jacobian)
      {
        // FIXME: we should replace this FEM with a hook to the AD fparser stuff
        const libMesh::Number epsilon = 1e-6;
        const libMesh::Number output_torque_deriv =
          (this->torque_function(libMesh::Point(0), fan_speed+epsilon) -
           this->torque_function(libMesh::Point(0), fan_speed-epsilon)) / (2*epsilon);

        Kss(0,0) += output_torque_deriv * context.get_elem_solution_derivative();
      }

    return;
  }
Ejemplo n.º 2
0
  void HeatTransferStabilizationHelper::compute_res_energy_steady_and_derivs
    ( AssemblyContext& context,
      unsigned int qp,
      const libMesh::Real rho,
      const libMesh::Real Cp,
      const libMesh::Real k,
      libMesh::Real &res,
      libMesh::Real &d_res_dT,
      libMesh::Gradient &d_res_dgradT,
      libMesh::Tensor   &d_res_dhessT,
      libMesh::Gradient &d_res_dU
    ) const
  {
    libMesh::Gradient grad_T = context.fixed_interior_gradient(this->_temp_vars.T_var(), qp);
    libMesh::Tensor hess_T = context.fixed_interior_hessian(this->_temp_vars.T_var(), qp);

    libMesh::RealGradient rhocpU( rho*Cp*context.fixed_interior_value(this->_flow_vars.u_var(), qp), 
                                  rho*Cp*context.fixed_interior_value(this->_flow_vars.v_var(), qp) );
    if(context.get_system().get_mesh().mesh_dimension() == 3)
      rhocpU(2) = rho*Cp*context.fixed_interior_value(this->_flow_vars.w_var(), qp);

    res = rhocpU*grad_T - k*(hess_T(0,0) + hess_T(1,1) + hess_T(2,2));
    d_res_dT = 0;
    d_res_dgradT = rhocpU;
    d_res_dhessT = 0;
    d_res_dhessT(0,0) = -k;
    d_res_dhessT(1,1) = -k;
    d_res_dhessT(2,2) = -k;
    d_res_dU = rho * Cp * grad_T;
  }
Ejemplo n.º 3
0
  libMesh::Real HeatTransferStabilizationHelper::compute_res_energy_steady( AssemblyContext& context,
                                                                            unsigned int qp,
                                                                            const libMesh::Real rho,
                                                                            const libMesh::Real Cp,
                                                                            const libMesh::Real k ) const
  {
    libMesh::Gradient grad_T = context.fixed_interior_gradient(this->_temp_vars.T_var(), qp);
    libMesh::Tensor hess_T = context.fixed_interior_hessian(this->_temp_vars.T_var(), qp);

    libMesh::RealGradient rhocpU( rho*Cp*context.fixed_interior_value(this->_flow_vars.u_var(), qp), 
                                  rho*Cp*context.fixed_interior_value(this->_flow_vars.v_var(), qp) );
    if(context.get_system().get_mesh().mesh_dimension() == 3)
      rhocpU(2) = rho*Cp*context.fixed_interior_value(this->_flow_vars.w_var(), qp);

    return rhocpU*grad_T - k*(hess_T(0,0) + hess_T(1,1) + hess_T(2,2));
  }
Ejemplo n.º 4
0
  libMesh::Real SpalartAllmarasStabilizationHelper::compute_res_spalart_steady( AssemblyContext& context,
                                                                                unsigned int qp, const libMesh::Real rho, const libMesh::Real mu, const libMesh::Real distance_qp ) const
  {
    // The flow velocity
    libMesh::Number u,v;
    u = context.interior_value(this->_flow_vars.u_var(), qp);
    v = context.interior_value(this->_flow_vars.v_var(), qp);

    libMesh::NumberVectorValue U(u,v);
    if ( context.get_system().get_mesh().mesh_dimension() == 3 )
      U(2) = context.interior_value(this->_flow_vars.w_var(), qp);

    libMesh::RealGradient grad_u = context.fixed_interior_gradient(this->_flow_vars.u_var(), qp);
    libMesh::RealGradient grad_v = context.fixed_interior_gradient(this->_flow_vars.v_var(), qp);

    libMesh::Number nu_value = context.interior_value(this->_turbulence_vars.nu_var(), qp);

    libMesh::RealGradient grad_nu = context.fixed_interior_gradient(this->_turbulence_vars.nu_var(), qp);

    libMesh::RealTensor hess_nu = context.fixed_interior_hessian(this->_turbulence_vars.nu_var(), qp);

    // The convection term
    libMesh::Number rhoUdotGradnu = rho*(U*grad_nu);

    // The diffusion term
    libMesh::Number inv_sigmadivnuplusnuphysicalGradnu = (1./this->_sa_params.get_sigma())*(grad_nu*grad_nu + ((nu_value + mu)*(hess_nu(0,0) + hess_nu(1,1) + (this->_dim == 3)?hess_nu(2,2):0)) + this->_sa_params.get_cb2()*grad_nu*grad_nu);

    // The source term
    libMesh::Real vorticity_value_qp = this->_spalart_allmaras_helper.vorticity(context, qp);
    libMesh::Real S_tilde = this->_sa_params.source_fn(nu_value, mu, distance_qp, vorticity_value_qp);
    libMesh::Real source_term = this->_sa_params.get_cb1()*S_tilde*nu_value;

    // The destruction term
    libMesh::Real fw = this->_sa_params.destruction_fn(nu_value, distance_qp, S_tilde);
    libMesh::Real destruction_term =  this->_sa_params.get_cw1()*fw*pow(nu_value/distance_qp, 2.);

    return rhoUdotGradnu + source_term + inv_sigmadivnuplusnuphysicalGradnu - destruction_term;
  }
Ejemplo n.º 5
0
	void PracticeCDRinv::element_time_derivative( bool compute_jacobian,
						AssemblyContext& context,
						CachedValues& /*cache*/ ){
	
		// The number of local degrees of freedom in each variable.
    const unsigned int n_c_dofs = context.get_dof_indices(_c_var).size();

    // We get some references to cell-specific data that
    // will be used to assemble the linear system.

    // Element Jacobian * quadrature weights for interior integration.
    const std::vector<libMesh::Real> &JxW =
      context.get_element_fe(_c_var)->get_JxW();

    // The temperature shape function gradients (in global coords.)
    // at interior quadrature points.
    const std::vector<std::vector<libMesh::RealGradient> >& dphi =
      context.get_element_fe(_c_var)->get_dphi();
    const std::vector<std::vector<libMesh::Real> >& phi = context.get_element_fe(_c_var)->get_phi();

    const std::vector<libMesh::Point>& q_points = 
      context.get_element_fe(_c_var)->get_xyz();
    
  	libMesh::DenseSubMatrix<libMesh::Number> &J_c_zc = context.get_elem_jacobian(_c_var, _zc_var);
		libMesh::DenseSubMatrix<libMesh::Number> &J_c_c = context.get_elem_jacobian(_c_var, _c_var);
	
		libMesh::DenseSubMatrix<libMesh::Number> &J_zc_c = context.get_elem_jacobian(_zc_var, _c_var);
		libMesh::DenseSubMatrix<libMesh::Number> &J_zc_fc = context.get_elem_jacobian(_zc_var, _fc_var);
	
		libMesh::DenseSubMatrix<libMesh::Number> &J_fc_zc = context.get_elem_jacobian(_fc_var, _zc_var);
		libMesh::DenseSubMatrix<libMesh::Number> &J_fc_fc = context.get_elem_jacobian(_fc_var, _fc_var);
		
		libMesh::DenseSubVector<libMesh::Number> &Rc = context.get_elem_residual( _c_var );;
		libMesh::DenseSubVector<libMesh::Number> &Rzc = context.get_elem_residual( _zc_var );
		libMesh::DenseSubVector<libMesh::Number> &Rfc = context.get_elem_residual( _fc_var );

    // Now we will build the element Jacobian and residual.
    // Constructing the residual requires the solution and its
    // gradient from the previous timestep.  This must be
    // calculated at each quadrature point by summing the
    // solution degree-of-freedom values by the appropriate
    // weight functions.
    unsigned int n_qpoints = context.get_element_qrule().n_points();

    for (unsigned int qp=0; qp != n_qpoints; qp++){

			libMesh::Number 
	      c = context.interior_value(_c_var, qp),
	      zc = context.interior_value(_zc_var, qp),
	      fc = context.interior_value(_fc_var, qp);
	    libMesh::Gradient 
	      grad_c = context.interior_gradient(_c_var, qp),
	      grad_zc = context.interior_gradient(_zc_var, qp),
	      grad_fc = context.interior_gradient(_fc_var, qp);
			
	  	//location of quadrature point
	  	const libMesh::Real ptx = q_points[qp](0);
	  	const libMesh::Real pty = q_points[qp](1);
			
   		int xind, yind;
   		libMesh::Real xdist = 1.e10; libMesh::Real ydist = 1.e10;
   		for(int ii=0; ii<x_pts.size(); ii++){
   			libMesh::Real tmp = std::abs(ptx - x_pts[ii]);
   			if(xdist > tmp){
   				xdist = tmp;
   				xind = ii;
   			}
   			else
   				break;
   		} 
   		for(int jj=0; jj<y_pts[xind].size(); jj++){
   			libMesh::Real tmp = std::abs(pty - y_pts[xind][jj]);
   			if(ydist > tmp){
   				ydist = tmp;
   				yind = jj;
   			}
   			else
   				break;
   		}
   		libMesh::Real u = vel_field[xind][yind](0);
   		libMesh::Real v = vel_field[xind][yind](1);

	    libMesh::NumberVectorValue U     (u,     v);

	
			// First, an i-loop over the  degrees of freedom.
			for (unsigned int i=0; i != n_c_dofs; i++){
				
				Rc(i) += JxW[qp]*(-_k*grad_zc*dphi[i][qp] + U*grad_zc*phi[i][qp] + 2*_R*zc*c*phi[i][qp]);
	      Rzc(i) += JxW[qp]*(-_k*grad_c*dphi[i][qp] - U*grad_c*phi[i][qp] + _R*c*c*phi[i][qp] + fc*phi[i][qp]);
     		Rfc(i) += JxW[qp]*(_beta*grad_fc*dphi[i][qp] + zc*phi[i][qp]);

				if (compute_jacobian){
					for (unsigned int j=0; j != n_c_dofs; j++){
						J_c_zc(i,j) += JxW[qp]*(-_k*dphi[j][qp]*dphi[i][qp] + U*dphi[j][qp]*phi[i][qp] 
															+ 2*_R*phi[j][qp]*c*phi[i][qp]);
						J_c_c(i,j) += JxW[qp]*(2*_R*zc*phi[j][qp]*phi[i][qp]);

						J_zc_c(i,j) += JxW[qp]*(-_k*dphi[j][qp]*dphi[i][qp] - U*dphi[j][qp]*phi[i][qp] 
																+ 2*_R*c*phi[j][qp]*phi[i][qp]);
						J_zc_fc(i,j) += JxW[qp]*(phi[j][qp]*phi[i][qp]);
	
	       		J_fc_zc(i,j) += JxW[qp]*(phi[j][qp]*phi[i][qp]);
       			J_fc_fc(i,j) += JxW[qp]*(_beta*dphi[j][qp]*dphi[i][qp]);
					} // end of the inner dof (j) loop
			  } // end - if (compute_jacobian && context.get_elem_solution_derivative())

			} // end of the outer dof (i) loop
    } // end of the quadrature point (qp) loop
    
	  for(unsigned int dnum=0; dnum<datavals.size(); dnum++){
	  	libMesh::Point data_point = datapts[dnum];
	  	if(context.get_elem().contains_point(data_point)){
	  		libMesh::Number cpred = context.point_value(_c_var, data_point);
	  		libMesh::Number cstar = datavals[dnum];
	  		
	  		unsigned int dim = context.get_system().get_mesh().mesh_dimension();
		    libMesh::FEType fe_type = context.get_element_fe(_c_var)->get_fe_type();
		    
		    //go between physical and reference element
		    libMesh::Point c_master = libMesh::FEInterface::inverse_map(dim, fe_type, &context.get_elem(), data_point); 	
		    
        std::vector<libMesh::Real> point_phi(n_c_dofs);
      	for (unsigned int i=0; i != n_c_dofs; i++){
      		//get value of basis function at mapped point in reference (master) element
          point_phi[i] = libMesh::FEInterface::shape(dim, fe_type, &context.get_elem(), i, c_master); 
        }
        
        for (unsigned int i=0; i != n_c_dofs; i++){
  	  		Rc(i) += (cpred - cstar)*point_phi[i];
	  
					if (compute_jacobian){
						for (unsigned int j=0; j != n_c_dofs; j++)
							J_c_c(i,j) += point_phi[j]*point_phi[i] ;
				  }
	  
  			}
	  	}
	  }

    return;
	
	}