void ElasticMembranePressure<PressureType>::element_time_derivative
( bool compute_jacobian, AssemblyContext & context )
{
unsigned int u_var = this->_disp_vars.u();
unsigned int v_var = this->_disp_vars.v();
unsigned int w_var = this->_disp_vars.w();
const unsigned int n_u_dofs = context.get_dof_indices(u_var).size();
const std::vector<libMesh::Real> &JxW =
this->get_fe(context)->get_JxW();
const std::vector<std::vector<libMesh::Real> >& u_phi =
this->get_fe(context)->get_phi();
const MultiphysicsSystem & system = context.get_multiphysics_system();
unsigned int u_dot_var = system.get_second_order_dot_var(u_var);
unsigned int v_dot_var = system.get_second_order_dot_var(v_var);
unsigned int w_dot_var = system.get_second_order_dot_var(w_var);
libMesh::DenseSubVector<libMesh::Number> &Fu = context.get_elem_residual(u_dot_var);
libMesh::DenseSubVector<libMesh::Number> &Fv = context.get_elem_residual(v_dot_var);
libMesh::DenseSubVector<libMesh::Number> &Fw = context.get_elem_residual(w_dot_var);
libMesh::DenseSubMatrix<libMesh::Number>& Kuv = context.get_elem_jacobian(u_dot_var,v_var);
libMesh::DenseSubMatrix<libMesh::Number>& Kuw = context.get_elem_jacobian(u_dot_var,w_var);
libMesh::DenseSubMatrix<libMesh::Number>& Kvu = context.get_elem_jacobian(v_dot_var,u_var);
libMesh::DenseSubMatrix<libMesh::Number>& Kvw = context.get_elem_jacobian(v_dot_var,w_var);
libMesh::DenseSubMatrix<libMesh::Number>& Kwu = context.get_elem_jacobian(w_dot_var,u_var);
libMesh::DenseSubMatrix<libMesh::Number>& Kwv = context.get_elem_jacobian(w_dot_var,v_var);
unsigned int n_qpoints = context.get_element_qrule().n_points();
// All shape function gradients are w.r.t. master element coordinates
const std::vector<std::vector<libMesh::Real> >& dphi_dxi =
this->get_fe(context)->get_dphidxi();
const std::vector<std::vector<libMesh::Real> >& dphi_deta =
this->get_fe(context)->get_dphideta();
const libMesh::DenseSubVector<libMesh::Number>& u_coeffs = context.get_elem_solution( u_var );
const libMesh::DenseSubVector<libMesh::Number>& v_coeffs = context.get_elem_solution( v_var );
const libMesh::DenseSubVector<libMesh::Number>& w_coeffs = context.get_elem_solution( w_var );
const std::vector<libMesh::RealGradient>& dxdxi = this->get_fe(context)->get_dxyzdxi();
const std::vector<libMesh::RealGradient>& dxdeta = this->get_fe(context)->get_dxyzdeta();
for (unsigned int qp=0; qp != n_qpoints; qp++)
{
// sqrt(det(a_cov)), a_cov being the covariant metric tensor of undeformed body
libMesh::Real sqrt_a = sqrt( dxdxi[qp]*dxdxi[qp]*dxdeta[qp]*dxdeta[qp]
- dxdxi[qp]*dxdeta[qp]*dxdeta[qp]*dxdxi[qp] );
// Gradients are w.r.t. master element coordinates
libMesh::Gradient grad_u, grad_v, grad_w;
for( unsigned int d = 0; d < n_u_dofs; d++ )
{
libMesh::RealGradient u_gradphi( dphi_dxi[d][qp], dphi_deta[d][qp] );
grad_u += u_coeffs(d)*u_gradphi;
grad_v += v_coeffs(d)*u_gradphi;
grad_w += w_coeffs(d)*u_gradphi;
}
libMesh::RealGradient dudxi( grad_u(0), grad_v(0), grad_w(0) );
libMesh::RealGradient dudeta( grad_u(1), grad_v(1), grad_w(1) );
libMesh::RealGradient A_1 = dxdxi[qp] + dudxi;
libMesh::RealGradient A_2 = dxdeta[qp] + dudeta;
libMesh::RealGradient A_3 = A_1.cross(A_2);
// Compute pressure at this quadrature point
libMesh::Real press = (*_pressure)(context,qp);
// Small optimization
libMesh::Real p_over_sa = press/sqrt_a;
/* The formula here is actually
P*\sqrt{\frac{A}{a}}*A_3, where A_3 is a unit vector
But, |A_3| = \sqrt{A} so the normalizing part kills
the \sqrt{A} in the numerator, so we can leave it out
and *not* normalize A_3.
*/
libMesh::RealGradient traction = p_over_sa*A_3;
for (unsigned int i=0; i != n_u_dofs; i++)
{
// Small optimization
libMesh::Real phi_times_jac = u_phi[i][qp]*JxW[qp];
Fu(i) -= traction(0)*phi_times_jac;
Fv(i) -= traction(1)*phi_times_jac;
Fw(i) -= traction(2)*phi_times_jac;
if( compute_jacobian )
{
for (unsigned int j=0; j != n_u_dofs; j++)
{
libMesh::RealGradient u_gradphi( dphi_dxi[j][qp], dphi_deta[j][qp] );
const libMesh::Real dt0_dv = p_over_sa*(u_gradphi(0)*A_2(2) - A_1(2)*u_gradphi(1));
const libMesh::Real dt0_dw = p_over_sa*(A_1(1)*u_gradphi(1) - u_gradphi(0)*A_2(1));
const libMesh::Real dt1_du = p_over_sa*(A_1(2)*u_gradphi(1) - u_gradphi(0)*A_2(2));
const libMesh::Real dt1_dw = p_over_sa*(u_gradphi(0)*A_2(0) - A_1(0)*u_gradphi(1));
const libMesh::Real dt2_du = p_over_sa*(u_gradphi(0)*A_2(1) - A_1(1)*u_gradphi(1));
const libMesh::Real dt2_dv = p_over_sa*(A_1(0)*u_gradphi(1) - u_gradphi(0)*A_2(0));
Kuv(i,j) -= dt0_dv*phi_times_jac;
Kuw(i,j) -= dt0_dw*phi_times_jac;
Kvu(i,j) -= dt1_du*phi_times_jac;
Kvw(i,j) -= dt1_dw*phi_times_jac;
Kwu(i,j) -= dt2_du*phi_times_jac;
Kwv(i,j) -= dt2_dv*phi_times_jac;
}
}
}
}
}
void ElasticCableRayleighDamping<StressStrainLaw>::damping_residual( bool compute_jacobian,
AssemblyContext& context,
CachedValues& /*cache*/)
{
// First, do the "mass" contribution
this->mass_residual_impl(compute_jacobian,
context,
&libMesh::FEMContext::interior_rate,
&libMesh::DiffContext::get_elem_solution_rate_derivative,
_mu_factor);
// Now do the stiffness contribution
const unsigned int n_u_dofs = context.get_dof_indices(this->_disp_vars.u()).size();
const std::vector<libMesh::Real> &JxW =
this->get_fe(context)->get_JxW();
// Residuals that we're populating
libMesh::DenseSubVector<libMesh::Number> &Fu = context.get_elem_residual(this->_disp_vars.u());
libMesh::DenseSubVector<libMesh::Number> &Fv = context.get_elem_residual(this->_disp_vars.v());
libMesh::DenseSubVector<libMesh::Number> &Fw = context.get_elem_residual(this->_disp_vars.w());
//Grab the Jacobian matrix as submatrices
//libMesh::DenseMatrix<libMesh::Number> &K = context.get_elem_jacobian();
libMesh::DenseSubMatrix<libMesh::Number> &Kuu = context.get_elem_jacobian(this->_disp_vars.u(),this->_disp_vars.u());
libMesh::DenseSubMatrix<libMesh::Number> &Kuv = context.get_elem_jacobian(this->_disp_vars.u(),this->_disp_vars.v());
libMesh::DenseSubMatrix<libMesh::Number> &Kuw = context.get_elem_jacobian(this->_disp_vars.u(),this->_disp_vars.w());
libMesh::DenseSubMatrix<libMesh::Number> &Kvu = context.get_elem_jacobian(this->_disp_vars.v(),this->_disp_vars.u());
libMesh::DenseSubMatrix<libMesh::Number> &Kvv = context.get_elem_jacobian(this->_disp_vars.v(),this->_disp_vars.v());
libMesh::DenseSubMatrix<libMesh::Number> &Kvw = context.get_elem_jacobian(this->_disp_vars.v(),this->_disp_vars.w());
libMesh::DenseSubMatrix<libMesh::Number> &Kwu = context.get_elem_jacobian(this->_disp_vars.w(),this->_disp_vars.u());
libMesh::DenseSubMatrix<libMesh::Number> &Kwv = context.get_elem_jacobian(this->_disp_vars.w(),this->_disp_vars.v());
libMesh::DenseSubMatrix<libMesh::Number> &Kww = context.get_elem_jacobian(this->_disp_vars.w(),this->_disp_vars.w());
unsigned int n_qpoints = context.get_element_qrule().n_points();
// All shape function gradients are w.r.t. master element coordinates
const std::vector<std::vector<libMesh::Real> >& dphi_dxi = this->get_fe(context)->get_dphidxi();
const libMesh::DenseSubVector<libMesh::Number>& u_coeffs = context.get_elem_solution( this->_disp_vars.u() );
const libMesh::DenseSubVector<libMesh::Number>& v_coeffs = context.get_elem_solution( this->_disp_vars.v() );
const libMesh::DenseSubVector<libMesh::Number>& w_coeffs = context.get_elem_solution( this->_disp_vars.w() );
const libMesh::DenseSubVector<libMesh::Number>& dudt_coeffs = context.get_elem_solution_rate( this->_disp_vars.u() );
const libMesh::DenseSubVector<libMesh::Number>& dvdt_coeffs = context.get_elem_solution_rate( this->_disp_vars.v() );
const libMesh::DenseSubVector<libMesh::Number>& dwdt_coeffs = context.get_elem_solution_rate( this->_disp_vars.w() );
// Need these to build up the covariant and contravariant metric tensors
const std::vector<libMesh::RealGradient>& dxdxi = this->get_fe(context)->get_dxyzdxi();
const unsigned int dim = 1; // The cable dimension is always 1 for this physics
for (unsigned int qp=0; qp != n_qpoints; qp++)
{
// Gradients are w.r.t. master element coordinates
libMesh::Gradient grad_u, grad_v, grad_w;
libMesh::Gradient dgradu_dt, dgradv_dt, dgradw_dt;
for( unsigned int d = 0; d < n_u_dofs; d++ )
{
libMesh::RealGradient u_gradphi( dphi_dxi[d][qp] );
grad_u += u_coeffs(d)*u_gradphi;
grad_v += v_coeffs(d)*u_gradphi;
grad_w += w_coeffs(d)*u_gradphi;
dgradu_dt += dudt_coeffs(d)*u_gradphi;
dgradv_dt += dvdt_coeffs(d)*u_gradphi;
dgradw_dt += dwdt_coeffs(d)*u_gradphi;
}
libMesh::RealGradient grad_x( dxdxi[qp](0) );
libMesh::RealGradient grad_y( dxdxi[qp](1) );
libMesh::RealGradient grad_z( dxdxi[qp](2) );
libMesh::TensorValue<libMesh::Real> a_cov, a_contra, A_cov, A_contra;
libMesh::Real lambda_sq = 0;
this->compute_metric_tensors( qp, *(this->get_fe(context)), context,
grad_u, grad_v, grad_w,
a_cov, a_contra, A_cov, A_contra,
lambda_sq );
// Compute stress tensor
libMesh::TensorValue<libMesh::Real> tau;
ElasticityTensor C;
this->_stress_strain_law.compute_stress_and_elasticity(dim,a_contra,a_cov,A_contra,A_cov,tau,C);
libMesh::Real jac = JxW[qp];
for (unsigned int i=0; i != n_u_dofs; i++)
{
libMesh::RealGradient u_gradphi( dphi_dxi[i][qp] );
libMesh::Real u_diag_factor = _lambda_factor*this->_A*jac*tau(0,0)*dgradu_dt(0)*u_gradphi(0);
libMesh::Real v_diag_factor = _lambda_factor*this->_A*jac*tau(0,0)*dgradv_dt(0)*u_gradphi(0);
libMesh::Real w_diag_factor = _lambda_factor*this->_A*jac*tau(0,0)*dgradw_dt(0)*u_gradphi(0);
const libMesh::Real C1 = _lambda_factor*this->_A*jac*C(0,0,0,0)*u_gradphi(0);
const libMesh::Real gamma_u = (grad_x(0)+grad_u(0));
const libMesh::Real gamma_v = (grad_y(0)+grad_v(0));
const libMesh::Real gamma_w = (grad_z(0)+grad_w(0));
const libMesh::Real x_term = C1*gamma_u;
const libMesh::Real y_term = C1*gamma_v;
const libMesh::Real z_term = C1*gamma_w;
const libMesh::Real dt_term = dgradu_dt(0)*gamma_u + dgradv_dt(0)*gamma_v + dgradw_dt(0)*gamma_w;
Fu(i) += u_diag_factor + x_term*dt_term;
Fv(i) += v_diag_factor + y_term*dt_term;
Fw(i) += w_diag_factor + z_term*dt_term;
}
if( compute_jacobian )
{
for(unsigned int i=0; i != n_u_dofs; i++)
{
libMesh::RealGradient u_gradphi_I( dphi_dxi[i][qp] );
for(unsigned int j=0; j != n_u_dofs; j++)
{
libMesh::RealGradient u_gradphi_J( dphi_dxi[j][qp] );
libMesh::Real common_factor = _lambda_factor*this->_A*jac*u_gradphi_I(0);
const libMesh::Real diag_term_1 = common_factor*tau(0,0)*u_gradphi_J(0)*context.get_elem_solution_rate_derivative();
const libMesh::Real dgamma_du = ( u_gradphi_J(0)*(grad_x(0)+grad_u(0)) );
const libMesh::Real dgamma_dv = ( u_gradphi_J(0)*(grad_y(0)+grad_v(0)) );
const libMesh::Real dgamma_dw = ( u_gradphi_J(0)*(grad_z(0)+grad_w(0)) );
const libMesh::Real diag_term_2_factor = common_factor*C(0,0,0,0)*context.get_elem_solution_derivative();
Kuu(i,j) += diag_term_1 + dgradu_dt(0)*diag_term_2_factor*dgamma_du;
Kuv(i,j) += dgradu_dt(0)*diag_term_2_factor*dgamma_dv;
Kuw(i,j) += dgradu_dt(0)*diag_term_2_factor*dgamma_dw;
Kvu(i,j) += dgradv_dt(0)*diag_term_2_factor*dgamma_du;
Kvv(i,j) += diag_term_1 + dgradv_dt(0)*diag_term_2_factor*dgamma_dv;
Kvw(i,j) += dgradv_dt(0)*diag_term_2_factor*dgamma_dw;
Kwu(i,j) += dgradw_dt(0)*diag_term_2_factor*dgamma_du;
Kwv(i,j) += dgradw_dt(0)*diag_term_2_factor*dgamma_dv;
Kww(i,j) += diag_term_1 + dgradw_dt(0)*diag_term_2_factor*dgamma_dw;
const libMesh::Real C1 = common_factor*C(0,0,0,0);
const libMesh::Real gamma_u = (grad_x(0)+grad_u(0));
const libMesh::Real gamma_v = (grad_y(0)+grad_v(0));
const libMesh::Real gamma_w = (grad_z(0)+grad_w(0));
const libMesh::Real x_term = C1*gamma_u;
const libMesh::Real y_term = C1*gamma_v;
const libMesh::Real z_term = C1*gamma_w;
const libMesh::Real ddtterm_du = u_gradphi_J(0)*(gamma_u*context.get_elem_solution_rate_derivative()
+ dgradu_dt(0)*context.get_elem_solution_derivative());
const libMesh::Real ddtterm_dv = u_gradphi_J(0)*(gamma_v*context.get_elem_solution_rate_derivative()
+ dgradv_dt(0)*context.get_elem_solution_derivative());
const libMesh::Real ddtterm_dw = u_gradphi_J(0)*(gamma_w*context.get_elem_solution_rate_derivative()
+ dgradw_dt(0)*context.get_elem_solution_derivative());
Kuu(i,j) += x_term*ddtterm_du;
Kuv(i,j) += x_term*ddtterm_dv;
Kuw(i,j) += x_term*ddtterm_dw;
Kvu(i,j) += y_term*ddtterm_du;
Kvv(i,j) += y_term*ddtterm_dv;
Kvw(i,j) += y_term*ddtterm_dw;
Kwu(i,j) += z_term*ddtterm_du;
Kwv(i,j) += z_term*ddtterm_dv;
Kww(i,j) += z_term*ddtterm_dw;
const libMesh::Real dt_term = dgradu_dt(0)*gamma_u + dgradv_dt(0)*gamma_v + dgradw_dt(0)*gamma_w;
// Here, we're missing derivatives of C(0,0,0,0) w.r.t. strain
// Nonzero for hyperelasticity models
const libMesh::Real dxterm_du = C1*u_gradphi_J(0)*context.get_elem_solution_derivative();
const libMesh::Real dyterm_dv = dxterm_du;
const libMesh::Real dzterm_dw = dxterm_du;
Kuu(i,j) += dxterm_du*dt_term;
Kvv(i,j) += dyterm_dv*dt_term;
Kww(i,j) += dzterm_dw*dt_term;
} // end j-loop
} // end i-loop
} // end if(compute_jacobian)
} // end qp loop
}
void ElasticMembraneConstantPressure::element_time_derivative( bool compute_jacobian,
AssemblyContext& context,
CachedValues& /*cache*/ )
{
const unsigned int n_u_dofs = context.get_dof_indices(_disp_vars.u()).size();
const std::vector<libMesh::Real> &JxW =
this->get_fe(context)->get_JxW();
const std::vector<std::vector<libMesh::Real> >& u_phi =
this->get_fe(context)->get_phi();
libMesh::DenseSubVector<libMesh::Number> &Fu = context.get_elem_residual(_disp_vars.u());
libMesh::DenseSubVector<libMesh::Number> &Fv = context.get_elem_residual(_disp_vars.v());
libMesh::DenseSubVector<libMesh::Number> &Fw = context.get_elem_residual(_disp_vars.w());
libMesh::DenseSubMatrix<libMesh::Number>& Kuv = context.get_elem_jacobian(_disp_vars.u(),_disp_vars.v());
libMesh::DenseSubMatrix<libMesh::Number>& Kuw = context.get_elem_jacobian(_disp_vars.u(),_disp_vars.w());
libMesh::DenseSubMatrix<libMesh::Number>& Kvu = context.get_elem_jacobian(_disp_vars.v(),_disp_vars.u());
libMesh::DenseSubMatrix<libMesh::Number>& Kvw = context.get_elem_jacobian(_disp_vars.v(),_disp_vars.w());
libMesh::DenseSubMatrix<libMesh::Number>& Kwu = context.get_elem_jacobian(_disp_vars.w(),_disp_vars.u());
libMesh::DenseSubMatrix<libMesh::Number>& Kwv = context.get_elem_jacobian(_disp_vars.w(),_disp_vars.v());
unsigned int n_qpoints = context.get_element_qrule().n_points();
// All shape function gradients are w.r.t. master element coordinates
const std::vector<std::vector<libMesh::Real> >& dphi_dxi =
this->get_fe(context)->get_dphidxi();
const std::vector<std::vector<libMesh::Real> >& dphi_deta =
this->get_fe(context)->get_dphideta();
const libMesh::DenseSubVector<libMesh::Number>& u_coeffs = context.get_elem_solution( _disp_vars.u() );
const libMesh::DenseSubVector<libMesh::Number>& v_coeffs = context.get_elem_solution( _disp_vars.v() );
const libMesh::DenseSubVector<libMesh::Number>& w_coeffs = context.get_elem_solution( _disp_vars.w() );
const std::vector<libMesh::RealGradient>& dxdxi = this->get_fe(context)->get_dxyzdxi();
const std::vector<libMesh::RealGradient>& dxdeta = this->get_fe(context)->get_dxyzdeta();
for (unsigned int qp=0; qp != n_qpoints; qp++)
{
// sqrt(det(a_cov)), a_cov being the covariant metric tensor of undeformed body
libMesh::Real sqrt_a = sqrt( dxdxi[qp]*dxdxi[qp]*dxdeta[qp]*dxdeta[qp]
- dxdxi[qp]*dxdeta[qp]*dxdeta[qp]*dxdxi[qp] );
// Gradients are w.r.t. master element coordinates
libMesh::Gradient grad_u, grad_v, grad_w;
for( unsigned int d = 0; d < n_u_dofs; d++ )
{
libMesh::RealGradient u_gradphi( dphi_dxi[d][qp], dphi_deta[d][qp] );
grad_u += u_coeffs(d)*u_gradphi;
grad_v += v_coeffs(d)*u_gradphi;
grad_w += w_coeffs(d)*u_gradphi;
}
libMesh::RealGradient dudxi( grad_u(0), grad_v(0), grad_w(0) );
libMesh::RealGradient dudeta( grad_u(1), grad_v(1), grad_w(1) );
libMesh::RealGradient A_1 = dxdxi[qp] + dudxi;
libMesh::RealGradient A_2 = dxdeta[qp] + dudeta;
libMesh::RealGradient A_3 = A_1.cross(A_2);
/* The formula here is actually
P*\sqrt{\frac{A}{a}}*A_3, where A_3 is a unit vector
But, |A_3| = \sqrt{A} so the normalizing part kills
the \sqrt{A} in the numerator, so we can leave it out
and *not* normalize A_3.
*/
libMesh::RealGradient traction = _pressure/sqrt_a*A_3;
libMesh::Real jac = JxW[qp];
for (unsigned int i=0; i != n_u_dofs; i++)
{
Fu(i) -= traction(0)*u_phi[i][qp]*jac;
Fv(i) -= traction(1)*u_phi[i][qp]*jac;
Fw(i) -= traction(2)*u_phi[i][qp]*jac;
if( compute_jacobian )
{
for (unsigned int j=0; j != n_u_dofs; j++)
{
libMesh::RealGradient u_gradphi( dphi_dxi[j][qp], dphi_deta[j][qp] );
const libMesh::Real dt0_dv = _pressure/sqrt_a*(u_gradphi(0)*A_2(2) - A_1(2)*u_gradphi(1));
const libMesh::Real dt0_dw = _pressure/sqrt_a*(A_1(1)*u_gradphi(1) - u_gradphi(0)*A_2(1));
const libMesh::Real dt1_du = _pressure/sqrt_a*(A_1(2)*u_gradphi(1) - u_gradphi(0)*A_2(2));
const libMesh::Real dt1_dw = _pressure/sqrt_a*(u_gradphi(0)*A_2(0) - A_1(0)*u_gradphi(1));
const libMesh::Real dt2_du = _pressure/sqrt_a*(u_gradphi(0)*A_2(1) - A_1(1)*u_gradphi(1));
const libMesh::Real dt2_dv = _pressure/sqrt_a*(A_1(0)*u_gradphi(1) - u_gradphi(0)*A_2(0));
Kuv(i,j) -= dt0_dv*u_phi[i][qp]*jac;
Kuw(i,j) -= dt0_dw*u_phi[i][qp]*jac;
Kvu(i,j) -= dt1_du*u_phi[i][qp]*jac;
Kvw(i,j) -= dt1_dw*u_phi[i][qp]*jac;
Kwu(i,j) -= dt2_du*u_phi[i][qp]*jac;
Kwv(i,j) -= dt2_dv*u_phi[i][qp]*jac;
}
}
}
}
return;
}
