C++ FluidState::fugacityCoefficient方法代码示例

 void assign(const FluidState& fs)
 {
     for (unsigned phaseIdx = 0; phaseIdx < numPhases; ++phaseIdx) {
         for (unsigned compIdx = 0; compIdx < numComponents; ++compIdx) {
             fugacityCoefficient_[phaseIdx][compIdx] = fs.fugacityCoefficient(phaseIdx, compIdx);
         }
     }
 }

 static Scalar calculateDefect_(const FluidState &params,
                                int phaseIdx,
                                const ComponentVector &targetFug)
 {
     Scalar result = 0.0;
     for (int i = 0; i < numComponents; ++i) {
         // sum of the fugacity defect weighted by the inverse
         // fugacity coefficient
         result += std::abs(
             (targetFug[i] - params.fugacity(phaseIdx, i))
             /
             params.fugacityCoefficient(phaseIdx, i) );
     };
     return result;
 }

    static void solve(FluidState &fluidState,
                      ParameterCache &paramCache,
                      int phasePresence,
                      const MMPCAuxConstraint<Evaluation> *auxConstraints,
                      unsigned numAuxConstraints,
                      bool setViscosity,
                      bool setInternalEnergy)
    {
        typedef MathToolbox<typename FluidState::Scalar> FsToolbox;
        static_assert(std::is_same<typename FluidState::Scalar, Evaluation>::value,
                      "The scalar type of the fluid state must be 'Evaluation'");

#ifndef NDEBUG
        // currently this solver can only handle fluid systems which
        // assume ideal mixtures of all fluids. TODO: relax this
        // (requires solving a non-linear system of equations, i.e. using
        // newton method.)
        for (unsigned phaseIdx = 0; phaseIdx < numPhases; ++phaseIdx) {
            assert(FluidSystem::isIdealMixture(phaseIdx));
        }
#endif

        // compute all fugacity coefficients
        for (unsigned phaseIdx = 0; phaseIdx < numPhases; ++phaseIdx) {
            paramCache.updatePhase(fluidState, phaseIdx);

            // since we assume ideal mixtures, the fugacity
            // coefficients of the components cannot depend on
            // composition, i.e. the parameters in the cache are valid
            for (unsigned compIdx = 0; compIdx < numComponents; ++compIdx) {
                Evaluation fugCoeff = FsToolbox::template toLhs<Evaluation>(
                    FluidSystem::fugacityCoefficient(fluidState, paramCache, phaseIdx, compIdx));
                fluidState.setFugacityCoefficient(phaseIdx, compIdx, fugCoeff);
            }
        }

        // create the linear system of equations which defines the
        // mole fractions
        static const int numEq = numComponents*numPhases;
        Dune::FieldMatrix<Evaluation, numEq, numEq> M(Toolbox::createConstant(0.0));
        Dune::FieldVector<Evaluation, numEq> x(Toolbox::createConstant(0.0));
        Dune::FieldVector<Evaluation, numEq> b(Toolbox::createConstant(0.0));

        // assemble the equations expressing the fact that the
        // fugacities of each component are equal in all phases
        for (unsigned compIdx = 0; compIdx < numComponents; ++compIdx) {
            const Evaluation& entryCol1 =
                fluidState.fugacityCoefficient(/*phaseIdx=*/0, compIdx)
                *fluidState.pressure(/*phaseIdx=*/0);
            unsigned col1Idx = compIdx;

            for (unsigned phaseIdx = 1; phaseIdx < numPhases; ++phaseIdx) {
                unsigned rowIdx = (phaseIdx - 1)*numComponents + compIdx;
                unsigned col2Idx = phaseIdx*numComponents + compIdx;

                const Evaluation& entryCol2 =
                    fluidState.fugacityCoefficient(phaseIdx, compIdx)
                    *fluidState.pressure(phaseIdx);

                M[rowIdx][col1Idx] = entryCol1;
                M[rowIdx][col2Idx] = -entryCol2;
            }
        }

        // assemble the equations expressing the assumption that the
        // sum of all mole fractions in each phase must be 1 for the
        // phases present.
        unsigned presentPhases = 0;
        for (unsigned phaseIdx = 0; phaseIdx < numPhases; ++phaseIdx) {
            if (!(phasePresence & (1 << phaseIdx)))
                continue;

            unsigned rowIdx = numComponents*(numPhases - 1) + presentPhases;
            presentPhases += 1;

            b[rowIdx] = Toolbox::createConstant(1.0);
            for (unsigned compIdx = 0; compIdx < numComponents; ++compIdx) {
                unsigned colIdx = phaseIdx*numComponents + compIdx;

                M[rowIdx][colIdx] = Toolbox::createConstant(1.0);
            }
        }

        assert(presentPhases + numAuxConstraints == numComponents);

        // incorperate the auxiliary equations, i.e., the explicitly given mole fractions
        for (unsigned auxEqIdx = 0; auxEqIdx < numAuxConstraints; ++auxEqIdx) {
            unsigned rowIdx = numComponents*(numPhases - 1) + presentPhases + auxEqIdx;
            b[rowIdx] = auxConstraints[auxEqIdx].value();

            unsigned colIdx = auxConstraints[auxEqIdx].phaseIdx()*numComponents + auxConstraints[auxEqIdx].compIdx();
            M[rowIdx][colIdx] = 1.0;
        }

        // solve for all mole fractions
        try {
            Dune::FMatrixPrecision<Scalar>::set_singular_limit(1e-50);
            M.solve(x, b);
        }
        catch (const Dune::FMatrixError &e) {
//.........这里部分代码省略.........