parameterized_thermoelastic_material.hpp

// Copyright (c) Lawrence Livermore National Security, LLC and
// other Serac Project Developers. See the top-level LICENSE file for
// details.
//
// SPDX-License-Identifier: (BSD-3-Clause)
 
#pragma once
 
#include "serac/numerics/functional/tensor.hpp"
#include "serac/numerics/functional/tuple.hpp"
#include "serac/physics/materials/green_saint_venant_thermoelastic.hpp"
 
namespace serac::thermomechanics {
 
struct ParameterizedThermoelasticMaterial {
  double density;    
  double E0;         
  double nu;         
  double C_v;        
  double alpha0;     
  double theta_ref;  
  double kappa0;     
 
  struct State {
    double strain_trace;  
  };
 
  static constexpr int numParameters() { return 3; }
 
  template <typename DispGradType, typename TempType, typename TempGradType, typename YoungsType, typename ConductType,
            typename CoupleType, int dim>
  auto operator()(State& state, const tensor<DispGradType, dim, dim>& grad_u, TempType theta,
                  const tensor<TempGradType, dim>& grad_theta, YoungsType DeltaE, ConductType DeltaKappa,
                  CoupleType ScaleAlpha) const
  {
    auto E = E0 * get<0>(DeltaE);
    auto kappa = kappa0 + get<0>(DeltaKappa);
    auto alpha = alpha0 * get<0>(ScaleAlpha);
 
    auto K = E / (3.0 * (1.0 - 2.0 * nu));
    auto G = 0.5 * E / (1.0 + nu);
    static constexpr auto I = Identity<dim>();
    auto F = grad_u + I;
    const auto Eg = greenStrain(grad_u);
    const auto trEg = tr(Eg);
 
    // stress
    const auto S = 2.0 * G * dev(Eg) + K * (trEg - 3.0 * alpha * (theta - theta_ref)) * I;
    const auto Piola = dot(F, S);
 
    // internal heat source
    const auto s0 = -3.0 * K * alpha * theta * (trEg - state.strain_trace);
 
    // heat flux
    const auto q0 = -kappa * grad_theta;
 
    state.strain_trace = get_value(trEg);
 
    return serac::tuple{Piola, C_v, s0, q0};
  }
};
}  // namespace serac::thermomechanics