opm-simulators/opm/simulators/flow/ReservoirCoupling.hpp
2025-01-17 22:06:22 +01:00

77 lines
3.3 KiB
C++

/*
Copyright 2024 Equinor ASA
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_RESERVOIR_COUPLING_HPP
#define OPM_RESERVOIR_COUPLING_HPP
#include <mpi.h>
#include <cmath>
#include <iostream>
#include <memory>
namespace Opm {
namespace ReservoirCoupling {
enum class MessageTag : int {
SlaveSimulationStartDate,
SlaveActivationDate,
SlaveProcessTermination,
SlaveNextReportDate,
SlaveNextTimeStep,
MasterGroupNames,
MasterGroupNamesSize,
};
// Helper functions
void custom_error_handler_(MPI_Comm* comm, int* err, const std::string &msg);
void setErrhandler(MPI_Comm comm, bool is_master);
// Utility class for comparing double values representing epoch dates (seconds since
// unix epoch) or elapsed time (seconds since the start of the simulation).
// NOTE: It is important that when comparing against start of a report step or similar, that
// that we do not miss these due to numerical issues. This is because communication between
// master and slave processes are based on these points in time.
// NOTE: Epoch values in this century (2000-2100) lies in the range of [1e9,4e9], and a double variable cannot
// represent such large values with high precision. For example, the date 01-01-2020 is equal
// to 1.5778368e9 seconds and adding 1e-7 seconds to this value will not change the value.
// So microseconds (1e-6) is approximately the smallest time unit we can represent for such a number.
// NOTE: Report steps seems to have a maximum resolution of whole seconds, see stepLength() in
// Schedule.cpp in opm-common, which returns the step length in seconds.
struct Seconds {
static constexpr double abstol = 1e-15;
static constexpr double reltol = 1e-15;
// We will will use the following expression to determine if two values a and b are equal:
// |a - b| <= tol = abstol + reltol * max(|a|, |b|)
// For example, assume abstol = reltol = 1e-15, then the following holds:
// - If |a| and |b| are below 1, then the absolute tolerance applies.
// - If a and b are above 1, then the relative tolerance applies.
// For example, for dates in the range 01-01-2000 to 01-01-2100, epoch values will be in the range
// [1e9, 4e9]. And we have 1e-15 * 1e9 = 1e-6, so numbers differing below one microsecond will
// be considered equal.
// NOTE: The above is not true for numbers close to zero, but we do not expect to compare such numbers.
static bool compare_eq(double a, double b);
static bool compare_gt(double a, double b);
static bool compare_gt_or_eq(double a, double b);
static bool compare_lt_or_eq(double a, double b);
};
} // namespace ReservoirCoupling
} // namespace Opm
#endif // OPM_RESERVOIR_COUPLING_HPP