opm-simulators/opm/autodiff/NewtonSolver_impl.hpp
2015-09-02 13:02:27 +02:00

251 lines
8.5 KiB
C++

/*
Copyright 2013, 2015 SINTEF ICT, Applied Mathematics.
Copyright 2015 Dr. Blatt - HPC-Simulation-Software & Services
Copyright 2015 NTNU
Copyright 2015 IRIS AS
This file is part of the Open Porous Media project (OPM).
OPM is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
OPM is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with OPM. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef OPM_NEWTONSOLVER_IMPL_HEADER_INCLUDED
#define OPM_NEWTONSOLVER_IMPL_HEADER_INCLUDED
#include <opm/autodiff/NewtonSolver.hpp>
namespace Opm
{
template <class PhysicalModel>
NewtonSolver<PhysicalModel>::NewtonSolver(const SolverParameters& param,
std::unique_ptr<PhysicalModel> model)
: param_(param),
model_(std::move(model)),
newtonIterations_(0),
linearIterations_(0)
{
}
template <class PhysicalModel>
unsigned int NewtonSolver<PhysicalModel>::newtonIterations () const
{
return newtonIterations_;
}
template <class PhysicalModel>
unsigned int NewtonSolver<PhysicalModel>::linearIterations () const
{
return linearIterations_;
}
template <class PhysicalModel>
int
NewtonSolver<PhysicalModel>::
step(const double dt,
ReservoirState& reservoir_state,
WellState& well_state)
{
// Do model-specific once-per-step calculations.
model_->prepareStep(dt, reservoir_state, well_state);
// For each iteration we store in a vector the norms of the residual of
// the mass balance for each active phase, the well flux and the well equations.
std::vector<std::vector<double>> residual_norms_history;
// Assemble residual and Jacobian, store residual norms.
model_->assemble(reservoir_state, well_state, true);
residual_norms_history.push_back(model_->computeResidualNorms());
// Set up for main Newton loop.
double omega = 1.0;
int iteration = 0;
bool converged = model_->getConvergence(dt, iteration);
const int sizeNonLinear = model_->sizeNonLinear();
V dxOld = V::Zero(sizeNonLinear);
bool isOscillate = false;
bool isStagnate = false;
const enum RelaxType relaxtype = relaxType();
int linIters = 0;
// ---------- Main Newton loop ----------
while ( (!converged && (iteration < maxIter())) || (minIter() > iteration)) {
// Compute the Newton update to the primary variables.
V dx = model_->solveJacobianSystem();
// Store number of linear iterations used.
linIters += model_->linearIterationsLastSolve();
// Stabilize the Newton update.
detectNewtonOscillations(residual_norms_history, iteration, relaxRelTol(), isOscillate, isStagnate);
if (isOscillate) {
omega -= relaxIncrement();
omega = std::max(omega, relaxMax());
if (model_->terminalOutputEnabled()) {
std::cout << " Oscillating behavior detected: Relaxation set to " << omega << std::endl;
}
}
stabilizeNewton(dx, dxOld, omega, relaxtype);
// Apply the update, the model may apply model-dependent
// limitations and chopping of the update.
model_->updateState(dx, reservoir_state, well_state);
// Assemble residual and Jacobian, store residual norms.
model_->assemble(reservoir_state, well_state, false);
residual_norms_history.push_back(model_->computeResidualNorms());
// increase iteration counter
++iteration;
converged = model_->getConvergence(dt, iteration);
}
if (!converged) {
if (model_->terminalOutputEnabled()) {
std::cerr << "WARNING: Failed to compute converged solution in " << iteration << " iterations." << std::endl;
}
return -1; // -1 indicates that the solver has to be restarted
}
linearIterations_ += linIters;
newtonIterations_ += iteration;
linearIterationsLast_ = linIters;
newtonIterationsLast_ = iteration;
// Do model-specific post-step actions.
model_->afterStep(dt, reservoir_state, well_state);
return linIters;
}
template <class PhysicalModel>
void NewtonSolver<PhysicalModel>::SolverParameters::
reset()
{
// default values for the solver parameters
relax_type_ = DAMPEN;
relax_max_ = 0.5;
relax_increment_ = 0.1;
relax_rel_tol_ = 0.2;
max_iter_ = 15;
min_iter_ = 1;
}
template <class PhysicalModel>
NewtonSolver<PhysicalModel>::SolverParameters::
SolverParameters()
{
// set default values
reset();
}
template <class PhysicalModel>
NewtonSolver<PhysicalModel>::SolverParameters::
SolverParameters( const parameter::ParameterGroup& param )
{
// set default values
reset();
// overload with given parameters
relax_max_ = param.getDefault("relax_max", relax_max_);
max_iter_ = param.getDefault("max_iter", max_iter_);
min_iter_ = param.getDefault("min_iter", min_iter_);
std::string relaxation_type = param.getDefault("relax_type", std::string("dampen"));
if (relaxation_type == "dampen") {
relax_type_ = DAMPEN;
} else if (relaxation_type == "sor") {
relax_type_ = SOR;
} else {
OPM_THROW(std::runtime_error, "Unknown Relaxtion Type " << relaxation_type);
}
}
template <class PhysicalModel>
void
NewtonSolver<PhysicalModel>::detectNewtonOscillations(const std::vector<std::vector<double>>& residual_history,
const int it, const double relaxRelTol_arg,
bool& oscillate, bool& stagnate) const
{
// The detection of oscillation in two primary variable results in the report of the detection
// of oscillation for the solver.
// Only the saturations are used for oscillation detection for the black oil model.
// Stagnate is not used for any treatment here.
if ( it < 2 ) {
oscillate = false;
stagnate = false;
return;
}
stagnate = true;
int oscillatePhase = 0;
const std::vector<double>& F0 = residual_history[it];
const std::vector<double>& F1 = residual_history[it - 1];
const std::vector<double>& F2 = residual_history[it - 2];
for (int p= 0; p < model_->numPhases(); ++p){
const double d1 = std::abs((F0[p] - F2[p]) / F0[p]);
const double d2 = std::abs((F0[p] - F1[p]) / F0[p]);
oscillatePhase += (d1 < relaxRelTol_arg) && (relaxRelTol_arg < d2);
// Process is 'stagnate' unless at least one phase
// exhibits significant residual change.
stagnate = (stagnate && !(std::abs((F1[p] - F2[p]) / F2[p]) > 1.0e-3));
}
oscillate = (oscillatePhase > 1);
}
template <class PhysicalModel>
void
NewtonSolver<PhysicalModel>::stabilizeNewton(V& dx, V& dxOld, const double omega,
const RelaxType relax_type) const
{
// The dxOld is updated with dx.
// If omega is equal to 1., no relaxtion will be appiled.
const V tempDxOld = dxOld;
dxOld = dx;
switch (relax_type) {
case DAMPEN:
if (omega == 1.) {
return;
}
dx = dx*omega;
return;
case SOR:
if (omega == 1.) {
return;
}
dx = dx*omega + (1.-omega)*tempDxOld;
return;
default:
OPM_THROW(std::runtime_error, "Can only handle DAMPEN and SOR relaxation type.");
}
return;
}
} // namespace Opm
#endif // OPM_FULLYIMPLICITSOLVER_IMPL_HEADER_INCLUDED