multifluid.hpp

#pragma once

#include "nlohmann/json.hpp"

#include <Eigen/Dense>
#include <fstream>
#include <string>
#include <cmath>
#include <optional>
#include "teqp/types.hpp"
#include "MultiComplex/MultiComplex.hpp"

// See https://eigen.tuxfamily.org/dox/TopicCustomizing_CustomScalar.html
namespace Eigen {
    template<typename TN> struct NumTraits<mcx::MultiComplex<TN>> : NumTraits<double> // permits to get the epsilon, dummy_precision, lowest, highest functions
    {
        enum {
            IsComplex = 1,
            IsInteger = 0,
            IsSigned = 1,
            RequireInitialization = 1,
            ReadCost = 1,
            AddCost = 3,
            MulCost = 3
        };
    };
}

template<typename EOSCollection>
class CorrespondingStatesContribution {

private:
    const EOSCollection EOSs;
public:
    CorrespondingStatesContribution(EOSCollection&& EOSs) : EOSs(EOSs) {};

    template<typename TauType, typename DeltaType, typename MoleFractions>
    auto alphar(const TauType& tau, const DeltaType& delta, const MoleFractions& molefracs) const {
        using resulttype = std::common_type_t<decltype(tau), decltype(molefracs[0]), decltype(delta)>; // Type promotion, without the const-ness
        resulttype alphar = 0.0;
        auto N = molefracs.size();
        for (auto i = 0; i < N; ++i) {
            alphar = alphar + molefracs[i] * EOSs[i].alphar(tau, delta);
        }
        return alphar;
    }
};

template<typename FCollection, typename DepartureFunctionCollection>
class DepartureContribution {

private:
    const FCollection F;
    const DepartureFunctionCollection funcs;
public:
    DepartureContribution(FCollection&& F, DepartureFunctionCollection&& funcs) : F(F), funcs(funcs) {};

    template<typename TauType, typename DeltaType, typename MoleFractions>
    auto alphar(const TauType& tau, const DeltaType& delta, const MoleFractions& molefracs) const {
        using resulttype = std::common_type_t<decltype(tau), decltype(molefracs[0]), decltype(delta)>; // Type promotion, without the const-ness
        resulttype alphar = 0.0;
        auto N = molefracs.size();
        for (auto i = 0; i < N; ++i) {
            for (auto j = i+1; j < N; ++j) {
                alphar = alphar + molefracs[i] * molefracs[j] * F(i, j) * funcs[i][j].alphar(tau, delta);
            }
        }
        return alphar;
    }
};