Scalar bringOilToSurface(FluidState& surfaceFluidState, Scalar alpha, const FluidState& reservoirFluidState, bool guessInitial)
{
enum {
numPhases = FluidSystem::numPhases,
waterPhaseIdx = FluidSystem::waterPhaseIdx,
gasPhaseIdx = FluidSystem::gasPhaseIdx,
oilPhaseIdx = FluidSystem::oilPhaseIdx,
numComponents = FluidSystem::numComponents
};
typedef Opm::NcpFlash<Scalar, FluidSystem> Flash;
typedef Opm::ThreePhaseMaterialTraits<Scalar, waterPhaseIdx, oilPhaseIdx, gasPhaseIdx> MaterialTraits;
typedef Opm::LinearMaterial<MaterialTraits> MaterialLaw;
typedef typename MaterialLaw::Params MaterialLawParams;
typedef Dune::FieldVector<Scalar, numComponents> ComponentVector;
const Scalar refPressure = 1.0135e5; // [Pa]
// set the parameters for the capillary pressure law
MaterialLawParams matParams;
for (unsigned phaseIdx = 0; phaseIdx < numPhases; ++phaseIdx) {
matParams.setPcMinSat(phaseIdx, 0.0);
matParams.setPcMaxSat(phaseIdx, 0.0);
}
matParams.finalize();
// retieve the global volumetric component molarities
surfaceFluidState.setTemperature(273.15 + 20);
ComponentVector molarities;
for (unsigned compIdx = 0; compIdx < numComponents; ++ compIdx)
molarities[compIdx] = reservoirFluidState.molarity(oilPhaseIdx, compIdx);
if (guessInitial) {
// we start at a fluid state with reservoir oil.
for (unsigned phaseIdx = 0; phaseIdx < numPhases; ++ phaseIdx) {
for (unsigned compIdx = 0; compIdx < numComponents; ++ compIdx) {
surfaceFluidState.setMoleFraction(phaseIdx,
compIdx,
reservoirFluidState.moleFraction(phaseIdx, compIdx));
}
surfaceFluidState.setDensity(phaseIdx, reservoirFluidState.density(phaseIdx));
surfaceFluidState.setPressure(phaseIdx, reservoirFluidState.pressure(phaseIdx));
surfaceFluidState.setSaturation(phaseIdx, 0.0);
}
surfaceFluidState.setSaturation(oilPhaseIdx, 1.0);
surfaceFluidState.setSaturation(gasPhaseIdx, 1.0 - surfaceFluidState.saturation(oilPhaseIdx));
}
typename FluidSystem::template ParameterCache<Scalar> paramCache;
paramCache.updateAll(surfaceFluidState);
// increase volume until we are at surface pressure. use the
// newton method for this
ComponentVector tmpMolarities;
for (int i = 0;; ++i) {
if (i >= 20)
throw Opm::NumericalIssue("Newton method did not converge after 20 iterations");
// calculate the deviation from the standard pressure
tmpMolarities = molarities;
tmpMolarities /= alpha;
Flash::template solve<MaterialLaw>(surfaceFluidState, matParams, paramCache, tmpMolarities);
Scalar f = surfaceFluidState.pressure(gasPhaseIdx) - refPressure;
// calculate the derivative of the deviation from the standard
// pressure
Scalar eps = alpha*1e-10;
tmpMolarities = molarities;
tmpMolarities /= alpha + eps;
Flash::template solve<MaterialLaw>(surfaceFluidState, matParams, paramCache, tmpMolarities);
Scalar fStar = surfaceFluidState.pressure(gasPhaseIdx) - refPressure;
Scalar fPrime = (fStar - f)/eps;
// newton update
Scalar delta = f/fPrime;
alpha -= delta;
if (std::abs(delta) < std::abs(alpha)*1e-9) {
break;
}
}
// calculate the final result
tmpMolarities = molarities;
tmpMolarities /= alpha;
Flash::template solve<MaterialLaw>(surfaceFluidState, matParams, paramCache, tmpMolarities);
return alpha;
}
static void solve(FluidState &fluidState,
const typename MaterialLaw::Params &matParams,
typename FluidSystem::template ParameterCache<typename FluidState::Scalar>& paramCache,
const Dune::FieldVector<typename FluidState::Scalar, numComponents>& globalMolarities,
Scalar tolerance = -1)
{
typedef typename FluidState::Scalar InputEval;
/////////////////////////
// Check if all fluid phases are incompressible
/////////////////////////
bool allIncompressible = true;
for (unsigned phaseIdx = 0; phaseIdx < numPhases; ++phaseIdx) {
if (FluidSystem::isCompressible(phaseIdx)) {
allIncompressible = false;
break;
}
}
if (allIncompressible) {
// yes, all fluid phases are incompressible. in this case the flash solver
// can only determine the saturations, not the pressures. (but this
// determination is much simpler than a full flash calculation.)
paramCache.updateAll(fluidState);
solveAllIncompressible_(fluidState, paramCache, globalMolarities);
return;
}
typedef Dune::FieldMatrix<InputEval, numEq, numEq> Matrix;
typedef Dune::FieldVector<InputEval, numEq> Vector;
typedef Opm::LocalAd::Evaluation<InputEval, numEq> FlashEval;
typedef Dune::FieldVector<FlashEval, numEq> FlashDefectVector;
typedef Opm::ImmiscibleFluidState<FlashEval, FluidSystem> FlashFluidState;
Dune::FMatrixPrecision<InputEval>::set_singular_limit(1e-35);
if (tolerance <= 0)
tolerance = std::min<Scalar>(1e-5,
1e8*std::numeric_limits<Scalar>::epsilon());
typename FluidSystem::template ParameterCache<FlashEval> flashParamCache;
flashParamCache.assignPersistentData(paramCache);
/////////////////////////
// Newton method
/////////////////////////
// Jacobian matrix
Matrix J;
// solution, i.e. phase composition
Vector deltaX;
// right hand side
Vector b;
Valgrind::SetUndefined(J);
Valgrind::SetUndefined(deltaX);
Valgrind::SetUndefined(b);
FlashFluidState flashFluidState;
assignFlashFluidState_<MaterialLaw>(fluidState, flashFluidState, matParams, flashParamCache);
// copy the global molarities to a vector of evaluations. Remember that the
// global molarities are constants. (but we need to copy them to a vector of
// FlashEvals anyway in order to avoid getting into hell's kitchen.)
Dune::FieldVector<FlashEval, numComponents> flashGlobalMolarities;
for (unsigned compIdx = 0; compIdx < numComponents; ++ compIdx)
flashGlobalMolarities[compIdx] = globalMolarities[compIdx];
FlashDefectVector defect;
const unsigned nMax = 50; // <- maximum number of newton iterations
for (unsigned nIdx = 0; nIdx < nMax; ++nIdx) {
// calculate Jacobian matrix and right hand side
evalDefect_(defect, flashFluidState, flashGlobalMolarities);
Valgrind::CheckDefined(defect);
// create field matrices and vectors out of the evaluation vector to solve
// the linear system of equations.
for (unsigned eqIdx = 0; eqIdx < numEq; ++ eqIdx) {
for (unsigned pvIdx = 0; pvIdx < numEq; ++ pvIdx)
J[eqIdx][pvIdx] = defect[eqIdx].derivatives[pvIdx];
b[eqIdx] = defect[eqIdx].value;
}
Valgrind::CheckDefined(J);
Valgrind::CheckDefined(b);
// Solve J*x = b
deltaX = 0;
try { J.solve(deltaX, b); }
catch (Dune::FMatrixError e) {
throw Opm::NumericalProblem(e.what());
}
Valgrind::CheckDefined(deltaX);
// update the fluid quantities.
Scalar relError = update_<MaterialLaw>(flashFluidState, flashParamCache, matParams, deltaX);
if (relError < tolerance) {
assignOutputFluidState_(flashFluidState, fluidState);
return;
}
}
OPM_THROW(Opm::NumericalProblem,
"ImmiscibleFlash solver failed: "
"{c_alpha^kappa} = {" << globalMolarities << "}, "
<< "T = " << fluidState.temperature(/*phaseIdx=*/0));
}