diff --git a/dumux/material/fluidsystems/brineco2.hh b/dumux/material/fluidsystems/brineco2.hh
index 800cecd550a9a7e0d011cd105ab8c53c661629fc..7c1c603735878c7a30d1fb19f0b0eb599c739493 100644
--- a/dumux/material/fluidsystems/brineco2.hh
+++ b/dumux/material/fluidsystems/brineco2.hh
@@ -88,10 +88,11 @@ namespace Detail {
* \ingroup Fluidsystems
* \brief Default policy for the Brine-CO2 fluid system
*/
-template<bool salinityIsConstant>
+template<bool salinityIsConstant, bool fastButSimplifiedRelations = false>
struct BrineCO2DefaultPolicy
{
static constexpr bool useConstantSalinity() { return salinityIsConstant; }
+ static constexpr bool useCO2GasDensityAsGasMixtureDensity() { return fastButSimplifiedRelations; }
};
/*!
@@ -330,6 +331,10 @@ public:
static void init(Scalar startTemp, Scalar endTemp, int tempSteps,
Scalar startPressure, Scalar endPressure, int pressureSteps)
{
+ std::cout << "The Brine-CO2 fluid system was configured with the following policy:\n";
+ std::cout << " - use constant salinity: " << std::boolalpha << Policy::useConstantSalinity() << "\n";
+ std::cout << " - use CO2 gas density as gas mixture density: " << std::boolalpha << Policy::useCO2GasDensityAsGasMixtureDensity() << std::endl;
+
// maybe set salinity of the constant salinity brine
if (useConstantSalinity)
ConstantSalinityBrine::constantSalinity = getParam<Scalar>("FluidSystem.Salinity", 0.3);
@@ -351,11 +356,19 @@ public:
static Scalar density(const FluidState& fluidState, int phaseIdx)
{
if (phaseIdx == liquidPhaseIdx)
- return liquidDensity_(fluidState);
+ return liquidDensityMixture_(fluidState);
- // in the end it comes down to a simplification of just CO2
else if (phaseIdx == gasPhaseIdx)
- return CO2::gasDensity(fluidState.temperature(phaseIdx), fluidState.pressure(phaseIdx));
+ {
+ if (Policy::useCO2GasDensityAsGasMixtureDensity())
+ // use the CO2 gas density only and neglect compositional effects
+ return CO2::gasDensity(fluidState.temperature(phaseIdx), fluidState.pressure(phaseIdx));
+ else
+ //account for compositional effects (water) in the gas phase
+ return gasDensityMixture_(fluidState.temperature(phaseIdx),
+ fluidState.pressure(phaseIdx),
+ fluidState.moleFraction(phaseIdx, comp0Idx));
+ }
DUNE_THROW(Dune::InvalidStateException, "Invalid phase index.");
}
@@ -709,15 +722,14 @@ public:
private:
- /***********************************************************************/
- /* */
- /* Total brine density with dissolved CO2 */
- /* rho_{b,CO2} = rho_w + contribution(salt) + contribution(CO2) */
- /* */
- /***********************************************************************/
- // computes the density of the liquid phase
+ /*!
+ * \brief Liquid-phase density calculation of a mixture of brine and CO2 accounting for compositional effects.
+ *
+ * \param fluidState An arbitrary fluid state
+ * \return liquidDensity the liquid-phase density
+ */
template<class FluidState>
- static Scalar liquidDensity_(const FluidState& fluidState)
+ static Scalar liquidDensityMixture_(const FluidState& fluidState)
{
const auto T = fluidState.temperature(liquidPhaseIdx);
const auto p = fluidState.pressure(liquidPhaseIdx);
@@ -777,7 +789,17 @@ private:
return rho_brine + contribCO2;
}
- // computes the density of the liquid water/CO2 mixture
+
+ /*!
+ * \brief Liquid-phase density for a mixture of CO2 in pure water.
+ * \note this is used by liquidDensityMixture_
+ *
+ * \param temperature The temperature
+ * \param pl the liquid-phase pressure
+ * \param xlH2O the liquid-phase H2O mole fraction
+ * \param xlCO2 the liquid-phase CO2 mole fraction
+ * \return the density of a mixture of CO2 in pure water
+ */
static Scalar liquidDensityWaterCO2_(Scalar temperature,
Scalar pl,
Scalar xlH2O,
@@ -799,6 +821,23 @@ private:
tempC*5.044e-7))) / 1.0e6;
return 1/(xlCO2 * V_phi/M_T + M_H2O * xlH2O / (rho_pure * M_T));
}
+
+ /*!
+ * \brief Gas-phase density calculation accounting for compositional effects.
+ *
+ * \param temperature The temperature
+ * \param pg the gas-phase pressure
+ * \param xgH2O the gas-phase H2O mole fraction
+ * \return the gas-phase density
+ */
+ static Scalar gasDensityMixture_(Scalar temperature, Scalar pg, Scalar xgH2O)
+ {
+ const Scalar pH2O = xgH2O*pg; //Dalton' Law
+ const Scalar pCO2 = pg - pH2O;
+ const Scalar gasDensityCO2 = CO2::gasDensity(temperature, pCO2);
+ const Scalar gasDensityH2O = H2O::gasDensity(temperature, pH2O);
+ return gasDensityCO2 + gasDensityH2O;
+ }
};
} // end namespace FluidSystems
diff --git a/test/material/fluidsystems/test_fluidsystems.cc b/test/material/fluidsystems/test_fluidsystems.cc
index 0053bab8693165f821a0a83c3f02f881dcbd5e65..d86f1be3969ccfbc554021cd5c5c446cdb0ed07d 100644
--- a/test/material/fluidsystems/test_fluidsystems.cc
+++ b/test/material/fluidsystems/test_fluidsystems.cc
@@ -177,6 +177,16 @@ int main()
using FluidSystem = FluidSystems::BrineCO2< Scalar, HeterogeneousCO2Tables::CO2Tables,
H2OType, FluidSystems::BrineCO2DefaultPolicy</*useConstantSalinity=*/false> >;
success += checkFluidSystem<Scalar, FluidSystem>( false ); }
+ { using H2OType = Components::TabulatedComponent<Components::H2O<Scalar>>;
+ using FluidSystem = FluidSystems::BrineCO2< Scalar, HeterogeneousCO2Tables::CO2Tables,
+ H2OType, FluidSystems::BrineCO2DefaultPolicy</*useConstantSalinity=*/true,
+ /*fastButSimplifiedRelations*/true> >;
+ success += checkFluidSystem<Scalar, FluidSystem>( false ); }
+ { using H2OType = Components::TabulatedComponent<Components::H2O<Scalar>>;
+ using FluidSystem = FluidSystems::BrineCO2< Scalar, HeterogeneousCO2Tables::CO2Tables,
+ H2OType, FluidSystems::BrineCO2DefaultPolicy</*useConstantSalinity=*/false,
+ /*fastButSimplifiedRelations*/true> >;
+ success += checkFluidSystem<Scalar, FluidSystem>( false ); }
// H2O -- Air
{ using H2OType = Components::SimpleH2O<Scalar>;
diff --git a/test/porousmediumflow/co2/implicit/heterogeneousproblem.hh b/test/porousmediumflow/co2/implicit/heterogeneousproblem.hh
index f1d36d4c344e0c170e2c498cc039cccadad4207c..b41d26dee4e94f7c01b7d05905c901477027929a 100644
--- a/test/porousmediumflow/co2/implicit/heterogeneousproblem.hh
+++ b/test/porousmediumflow/co2/implicit/heterogeneousproblem.hh
@@ -34,6 +34,8 @@
#include <dumux/porousmediumflow/problem.hh>
#include <dumux/porousmediumflow/co2/model.hh>
+#include <dumux/material/components/tabulatedcomponent.hh>
+#include <dumux/material/components/h2o.hh>
#include <dumux/material/fluidsystems/brineco2.hh>
#include <dumux/discretization/box/scvftoscvboundarytypes.hh>
@@ -69,8 +71,11 @@ SET_TYPE_PROP(HeterogeneousTypeTag, SpatialParams, HeterogeneousSpatialParams<ty
typename GET_PROP_TYPE(TypeTag, Scalar)>);
// Set fluid configuration
-SET_TYPE_PROP(HeterogeneousTypeTag, FluidSystem, FluidSystems::BrineCO2<typename GET_PROP_TYPE(TypeTag, Scalar),
- HeterogeneousCO2Tables::CO2Tables>);
+SET_TYPE_PROP(HeterogeneousTypeTag, FluidSystem,
+ FluidSystems::BrineCO2<typename GET_PROP_TYPE(TypeTag, Scalar),
+ HeterogeneousCO2Tables::CO2Tables,
+ Components::TabulatedComponent<Components::H2O<typename GET_PROP_TYPE(TypeTag, Scalar)>>,
+ FluidSystems::BrineCO2DefaultPolicy</*constantSalinity=*/true, /*simpleButFast=*/true>>);
// Use Moles
SET_BOOL_PROP(HeterogeneousTypeTag, UseMoles, false);