GRINS-0.7.0
elastic_cable_rayleigh_damping.C
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1 //-----------------------------------------------------------------------bl-
2 //--------------------------------------------------------------------------
3 //
4 // GRINS - General Reacting Incompressible Navier-Stokes
5 //
6 // Copyright (C) 2014-2016 Paul T. Bauman, Roy H. Stogner
7 // Copyright (C) 2010-2013 The PECOS Development Team
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23 //-----------------------------------------------------------------------el-
24 
25 // This class
26 #include "grins/elastic_cable_rayleigh_damping.h"
27 
28 // GRINS
29 #include "grins/physics_naming.h"
30 #include "grins/elasticity_tensor.h"
31 
32 // libMesh
33 #include "libmesh/getpot.h"
34 #include "libmesh/quadrature.h"
35 
36 namespace GRINS
37 {
38  template<typename StressStrainLaw>
39  ElasticCableRayleighDamping<StressStrainLaw>::ElasticCableRayleighDamping( const PhysicsName& physics_name,
40  const GetPot& input,
41  bool is_compressible )
42  : ElasticCableBase<StressStrainLaw>(physics_name,input,is_compressible),
43  _lambda_factor(input("Physics/"+PhysicsNaming::elastic_cable_rayleigh_damping()+"/lambda_factor",0.0)),
44  _mu_factor(input("Physics/"+PhysicsNaming::elastic_cable_rayleigh_damping()+"/mu_factor",0.0))
45  {
46  if( !input.have_variable("Physics/"+PhysicsNaming::elastic_cable_rayleigh_damping()+"/lambda_factor") )
47  libmesh_error_msg("ERROR: Couldn't find Physics/"+PhysicsNaming::elastic_cable_rayleigh_damping()+"/lambda_factor in input!");
48 
49  if( !input.have_variable("Physics/"+PhysicsNaming::elastic_cable_rayleigh_damping()+"/mu_factor") )
50  libmesh_error_msg("ERROR: Couldn't find Physics/"+PhysicsNaming::elastic_cable_rayleigh_damping()+"/mu_factor in input!");
51 
52 
53  // If the user specified enabled subdomains in this Physics section,
54  // that's an error; we're slave to ElasticCable.
55  if( input.have_variable("Physics/"+PhysicsNaming::elastic_cable_rayleigh_damping()+"/enabled_subdomains" ) )
56  libmesh_error_msg("ERROR: Cannot specify subdomains for "
57  +PhysicsNaming::elastic_cable_rayleigh_damping()
58  +"! Must specify subdomains through "
59  +PhysicsNaming::elastic_cable()+".");
60 
61  this->parse_enabled_subdomains(input,PhysicsNaming::elastic_cable());
62  }
63 
64  template<typename StressStrainLaw>
65  void ElasticCableRayleighDamping<StressStrainLaw>::damping_residual( bool compute_jacobian,
66  AssemblyContext& context,
67  CachedValues& /*cache*/)
68  {
69  // First, do the "mass" contribution
70  this->mass_residual_impl(compute_jacobian,
71  context,
72  &libMesh::FEMContext::interior_rate,
73  &libMesh::DiffContext::get_elem_solution_rate_derivative,
74  _mu_factor);
75 
76  // Now do the stiffness contribution
77  const unsigned int n_u_dofs = context.get_dof_indices(this->_disp_vars.u()).size();
78 
79  const std::vector<libMesh::Real> &JxW =
80  this->get_fe(context)->get_JxW();
81 
82  // Residuals that we're populating
83  libMesh::DenseSubVector<libMesh::Number> &Fu = context.get_elem_residual(this->_disp_vars.u());
84  libMesh::DenseSubVector<libMesh::Number> &Fv = context.get_elem_residual(this->_disp_vars.v());
85  libMesh::DenseSubVector<libMesh::Number> &Fw = context.get_elem_residual(this->_disp_vars.w());
86 
87  //Grab the Jacobian matrix as submatrices
88  //libMesh::DenseMatrix<libMesh::Number> &K = context.get_elem_jacobian();
89  libMesh::DenseSubMatrix<libMesh::Number> &Kuu = context.get_elem_jacobian(this->_disp_vars.u(),this->_disp_vars.u());
90  libMesh::DenseSubMatrix<libMesh::Number> &Kuv = context.get_elem_jacobian(this->_disp_vars.u(),this->_disp_vars.v());
91  libMesh::DenseSubMatrix<libMesh::Number> &Kuw = context.get_elem_jacobian(this->_disp_vars.u(),this->_disp_vars.w());
92  libMesh::DenseSubMatrix<libMesh::Number> &Kvu = context.get_elem_jacobian(this->_disp_vars.v(),this->_disp_vars.u());
93  libMesh::DenseSubMatrix<libMesh::Number> &Kvv = context.get_elem_jacobian(this->_disp_vars.v(),this->_disp_vars.v());
94  libMesh::DenseSubMatrix<libMesh::Number> &Kvw = context.get_elem_jacobian(this->_disp_vars.v(),this->_disp_vars.w());
95  libMesh::DenseSubMatrix<libMesh::Number> &Kwu = context.get_elem_jacobian(this->_disp_vars.w(),this->_disp_vars.u());
96  libMesh::DenseSubMatrix<libMesh::Number> &Kwv = context.get_elem_jacobian(this->_disp_vars.w(),this->_disp_vars.v());
97  libMesh::DenseSubMatrix<libMesh::Number> &Kww = context.get_elem_jacobian(this->_disp_vars.w(),this->_disp_vars.w());
98 
99  unsigned int n_qpoints = context.get_element_qrule().n_points();
100 
101  // All shape function gradients are w.r.t. master element coordinates
102  const std::vector<std::vector<libMesh::Real> >& dphi_dxi = this->get_fe(context)->get_dphidxi();
103 
104  const libMesh::DenseSubVector<libMesh::Number>& u_coeffs = context.get_elem_solution( this->_disp_vars.u() );
105  const libMesh::DenseSubVector<libMesh::Number>& v_coeffs = context.get_elem_solution( this->_disp_vars.v() );
106  const libMesh::DenseSubVector<libMesh::Number>& w_coeffs = context.get_elem_solution( this->_disp_vars.w() );
107 
108  const libMesh::DenseSubVector<libMesh::Number>& dudt_coeffs = context.get_elem_solution_rate( this->_disp_vars.u() );
109  const libMesh::DenseSubVector<libMesh::Number>& dvdt_coeffs = context.get_elem_solution_rate( this->_disp_vars.v() );
110  const libMesh::DenseSubVector<libMesh::Number>& dwdt_coeffs = context.get_elem_solution_rate( this->_disp_vars.w() );
111 
112  // Need these to build up the covariant and contravariant metric tensors
113  const std::vector<libMesh::RealGradient>& dxdxi = this->get_fe(context)->get_dxyzdxi();
114 
115  const unsigned int dim = 1; // The cable dimension is always 1 for this physics
116 
117  for (unsigned int qp=0; qp != n_qpoints; qp++)
118  {
119  // Gradients are w.r.t. master element coordinates
120  libMesh::Gradient grad_u, grad_v, grad_w;
121  libMesh::Gradient dgradu_dt, dgradv_dt, dgradw_dt;
122 
123  for( unsigned int d = 0; d < n_u_dofs; d++ )
124  {
125  libMesh::RealGradient u_gradphi( dphi_dxi[d][qp] );
126  grad_u += u_coeffs(d)*u_gradphi;
127  grad_v += v_coeffs(d)*u_gradphi;
128  grad_w += w_coeffs(d)*u_gradphi;
129 
130  dgradu_dt += dudt_coeffs(d)*u_gradphi;
131  dgradv_dt += dvdt_coeffs(d)*u_gradphi;
132  dgradw_dt += dwdt_coeffs(d)*u_gradphi;
133  }
134 
135  libMesh::RealGradient grad_x( dxdxi[qp](0) );
136  libMesh::RealGradient grad_y( dxdxi[qp](1) );
137  libMesh::RealGradient grad_z( dxdxi[qp](2) );
138 
139  libMesh::TensorValue<libMesh::Real> a_cov, a_contra, A_cov, A_contra;
140  libMesh::Real lambda_sq = 0;
141 
142  this->compute_metric_tensors( qp, *(this->get_fe(context)), context,
143  grad_u, grad_v, grad_w,
144  a_cov, a_contra, A_cov, A_contra,
145  lambda_sq );
146 
147  // Compute stress tensor
148  libMesh::TensorValue<libMesh::Real> tau;
149  ElasticityTensor C;
150  this->_stress_strain_law.compute_stress_and_elasticity(dim,a_contra,a_cov,A_contra,A_cov,tau,C);
151 
152  libMesh::Real jac = JxW[qp];
153 
154  for (unsigned int i=0; i != n_u_dofs; i++)
155  {
156  libMesh::RealGradient u_gradphi( dphi_dxi[i][qp] );
157 
158  libMesh::Real u_diag_factor = _lambda_factor*this->_A*jac*tau(0,0)*dgradu_dt(0)*u_gradphi(0);
159  libMesh::Real v_diag_factor = _lambda_factor*this->_A*jac*tau(0,0)*dgradv_dt(0)*u_gradphi(0);
160  libMesh::Real w_diag_factor = _lambda_factor*this->_A*jac*tau(0,0)*dgradw_dt(0)*u_gradphi(0);
161 
162  const libMesh::Real C1 = _lambda_factor*this->_A*jac*C(0,0,0,0)*u_gradphi(0);
163 
164  const libMesh::Real gamma_u = (grad_x(0)+grad_u(0));
165  const libMesh::Real gamma_v = (grad_y(0)+grad_v(0));
166  const libMesh::Real gamma_w = (grad_z(0)+grad_w(0));
167 
168  const libMesh::Real x_term = C1*gamma_u;
169  const libMesh::Real y_term = C1*gamma_v;
170  const libMesh::Real z_term = C1*gamma_w;
171 
172  const libMesh::Real dt_term = dgradu_dt(0)*gamma_u + dgradv_dt(0)*gamma_v + dgradw_dt(0)*gamma_w;
173 
174  Fu(i) += u_diag_factor + x_term*dt_term;
175  Fv(i) += v_diag_factor + y_term*dt_term;
176  Fw(i) += w_diag_factor + z_term*dt_term;
177  }
178 
179  if( compute_jacobian )
180  {
181  for(unsigned int i=0; i != n_u_dofs; i++)
182  {
183  libMesh::RealGradient u_gradphi_I( dphi_dxi[i][qp] );
184 
185  for(unsigned int j=0; j != n_u_dofs; j++)
186  {
187  libMesh::RealGradient u_gradphi_J( dphi_dxi[j][qp] );
188 
189  libMesh::Real common_factor = _lambda_factor*this->_A*jac*u_gradphi_I(0);
190 
191  const libMesh::Real diag_term_1 = common_factor*tau(0,0)*u_gradphi_J(0)*context.get_elem_solution_rate_derivative();
192 
193  const libMesh::Real dgamma_du = ( u_gradphi_J(0)*(grad_x(0)+grad_u(0)) );
194 
195  const libMesh::Real dgamma_dv = ( u_gradphi_J(0)*(grad_y(0)+grad_v(0)) );
196 
197  const libMesh::Real dgamma_dw = ( u_gradphi_J(0)*(grad_z(0)+grad_w(0)) );
198 
199  const libMesh::Real diag_term_2_factor = common_factor*C(0,0,0,0)*context.get_elem_solution_derivative();
200 
201  Kuu(i,j) += diag_term_1 + dgradu_dt(0)*diag_term_2_factor*dgamma_du;
202  Kuv(i,j) += dgradu_dt(0)*diag_term_2_factor*dgamma_dv;
203  Kuw(i,j) += dgradu_dt(0)*diag_term_2_factor*dgamma_dw;
204 
205  Kvu(i,j) += dgradv_dt(0)*diag_term_2_factor*dgamma_du;
206  Kvv(i,j) += diag_term_1 + dgradv_dt(0)*diag_term_2_factor*dgamma_dv;
207  Kvw(i,j) += dgradv_dt(0)*diag_term_2_factor*dgamma_dw;
208 
209  Kwu(i,j) += dgradw_dt(0)*diag_term_2_factor*dgamma_du;
210  Kwv(i,j) += dgradw_dt(0)*diag_term_2_factor*dgamma_dv;
211  Kww(i,j) += diag_term_1 + dgradw_dt(0)*diag_term_2_factor*dgamma_dw;
212 
213  const libMesh::Real C1 = common_factor*C(0,0,0,0);
214 
215  const libMesh::Real gamma_u = (grad_x(0)+grad_u(0));
216  const libMesh::Real gamma_v = (grad_y(0)+grad_v(0));
217  const libMesh::Real gamma_w = (grad_z(0)+grad_w(0));
218 
219  const libMesh::Real x_term = C1*gamma_u;
220  const libMesh::Real y_term = C1*gamma_v;
221  const libMesh::Real z_term = C1*gamma_w;
222 
223  const libMesh::Real ddtterm_du = u_gradphi_J(0)*(gamma_u*context.get_elem_solution_rate_derivative()
224  + dgradu_dt(0)*context.get_elem_solution_derivative());
225 
226  const libMesh::Real ddtterm_dv = u_gradphi_J(0)*(gamma_v*context.get_elem_solution_rate_derivative()
227  + dgradv_dt(0)*context.get_elem_solution_derivative());
228 
229  const libMesh::Real ddtterm_dw = u_gradphi_J(0)*(gamma_w*context.get_elem_solution_rate_derivative()
230  + dgradw_dt(0)*context.get_elem_solution_derivative());
231 
232  Kuu(i,j) += x_term*ddtterm_du;
233  Kuv(i,j) += x_term*ddtterm_dv;
234  Kuw(i,j) += x_term*ddtterm_dw;
235 
236  Kvu(i,j) += y_term*ddtterm_du;
237  Kvv(i,j) += y_term*ddtterm_dv;
238  Kvw(i,j) += y_term*ddtterm_dw;
239 
240  Kwu(i,j) += z_term*ddtterm_du;
241  Kwv(i,j) += z_term*ddtterm_dv;
242  Kww(i,j) += z_term*ddtterm_dw;
243 
244  const libMesh::Real dt_term = dgradu_dt(0)*gamma_u + dgradv_dt(0)*gamma_v + dgradw_dt(0)*gamma_w;
245 
246  // Here, we're missing derivatives of C(0,0,0,0) w.r.t. strain
247  // Nonzero for hyperelasticity models
248  const libMesh::Real dxterm_du = C1*u_gradphi_J(0)*context.get_elem_solution_derivative();
249  const libMesh::Real dyterm_dv = dxterm_du;
250  const libMesh::Real dzterm_dw = dxterm_du;
251 
252  Kuu(i,j) += dxterm_du*dt_term;
253  Kvv(i,j) += dyterm_dv*dt_term;
254  Kww(i,j) += dzterm_dw*dt_term;
255 
256  } // end j-loop
257  } // end i-loop
258  } // end if(compute_jacobian)
259  } // end qp loop
260  }
261 
262 } // end namespace GRINS
GRINS::PhysicsNaming::elastic_cable_rayleigh_damping
static PhysicsName elastic_cable_rayleigh_damping()
Definition: physics_naming.h:170
GRINS::PhysicsNaming::elastic_cable
static PhysicsName elastic_cable()
Definition: physics_naming.h:167
GRINS
GRINS namespace.
Definition: arrhenius_catalycity.h:31
physics_naming.h
elasticity_tensor.h
GRINS::PhysicsName
std::string PhysicsName
Definition: physics_naming.h:33
GRINS::Physics::parse_enabled_subdomains
void parse_enabled_subdomains(const GetPot &input, const std::string &physics_name)
Definition: physics.C:64
GRINS::ElasticCableRayleighDamping::damping_residual
virtual void damping_residual(bool compute_jacobian, AssemblyContext &context, CachedValues &)
Time dependent part(s) of physics for element interiors.
Definition: elastic_cable_rayleigh_damping.C:65
elastic_cable_rayleigh_damping.h
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