IsochoricNeoHookean.cpp

Go to the documentation of this file.

#include "IsochoricNeoHookean.hpp"
 
namespace polyfem::assembler
{
    IsochoricNeoHookean::IsochoricNeoHookean()
    {
    }
 
    void IsochoricNeoHookean::add_multimaterial(const int index, const json &params, const Units &units)
    {
        assert(size() == 2 || size() == 3);
 
        params_.add_multimaterial(index, params, false, units.stress());
    }
 
    std::map<std::string, Assembler::ParamFunc> IsochoricNeoHookean::parameters() const
    {
        std::map<std::string, ParamFunc> res;
        const auto &params = params_;
        const int size = this->size();
 
        res["lambda"] = [&params](const RowVectorNd &uv, const RowVectorNd &p, double t, int e) {
            double lambda, mu;
 
            params.lambda_mu(uv, p, t, e, lambda, mu);
            return lambda;
        };
 
        res["mu"] = [&params](const RowVectorNd &uv, const RowVectorNd &p, double t, int e) {
            double lambda, mu;
 
            params.lambda_mu(uv, p, t, e, lambda, mu);
            return mu;
        };
 
        res["E"] = [&params, size](const RowVectorNd &uv, const RowVectorNd &p, double t, int e) {
            double lambda, mu;
            params.lambda_mu(uv, p, t, e, lambda, mu);
 
            if (size == 3)
                return mu * (3.0 * lambda + 2.0 * mu) / (lambda + mu);
            else
                return 2 * mu * (2.0 * lambda + 2.0 * mu) / (lambda + 2.0 * mu);
        };
 
        res["nu"] = [&params, size](const RowVectorNd &uv, const RowVectorNd &p, double t, int e) {
            double lambda, mu;
 
            params.lambda_mu(uv, p, t, e, lambda, mu);
 
            if (size == 3)
                return lambda / (2.0 * (lambda + mu));
            else
                return lambda / (lambda + 2.0 * mu);
        };
 
        return res;
    }
} // namespace polyfem::assembler