opm-simulators/opm/autodiff/WellStateMultiSegment.hpp

/*
  Copyright 2015 SINTEF ICT, Applied Mathematics.

  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_WELLSTATEMULTISEGMENT_HEADER_INCLUDED
#define OPM_WELLSTATEMULTISEGMENT_HEADER_INCLUDED


#include <opm/core/wells.h>
#include <opm/core/well_controls.h>
#include <opm/common/ErrorMacros.hpp>
#include <opm/autodiff/AutoDiffBlock.hpp>
#include <opm/autodiff/WellMultiSegment.hpp>
#include <opm/autodiff/WellStateFullyImplicitBlackoil.hpp>
#include <vector>
#include <cassert>
#include <string>
#include <utility>
#include <map>
#include <algorithm>
#include <array>

namespace Opm
{

    /// The state of a set of multi-sgemnet wells
    /// since we are avoiding to use the old wells structure
    /// it makes it might be a good idea not to relate this State to the WellState
    class WellStateMultiSegment
         : public WellStateFullyImplicitBlackoil
    {
    public:

        typedef WellStateFullyImplicitBlackoil Base;
        typedef WellMultiSegment::V V;

        typedef struct {
            int well_number;
            int start_segment;
            int number_of_segments;
            int start_perforation;
            int number_of_perforations;
            std::vector<int> start_perforation_segment; // the starting position of perforation inside the segment
            std::vector<int> number_of_perforations_segment; // the numbers for perforations for the segments
        } SegmentedMapentryType;

        typedef std::map<std::string, SegmentedMapentryType> SegmentedWellMapType;
        // MAYNOT NEED THIS

        /// Allocate and initialize if wells is non-null.  Also tries
        /// to give useful initial values to the bhp(), wellRates()
        /// and perfPhaseRates() fields, depending on controls
        /// the PrevState here must be the same with State
        template <class ReservoirState, class PrevWellState>
        void init(const std::vector<WellMultiSegmentConstPtr>& wells, const ReservoirState& state, const PrevWellState& prevState)
        {
            const int nw = wells.size();
            if (nw == 0) {
                return;
            }

            const int np = wells[0]->numberOfPhases(); // number of the phases

            int nperf = 0; // the number of the perforations
            int nseg = 0; // the nubmer of the segments

            for (int iw = 0; iw < nw; ++iw) {
                nperf += wells[iw]->numberOfPerforations();
                nseg += wells[iw]->numberOfSegments();
            }

            bhp().resize(nw);
            thp().resize(nw);
            top_segment_loc_.resize(nw);
            temperature().resize(nw, 273.15 + 20); // standard temperature for now

            // deciding to add the following variables temporarily
            // TODO: making it better later
            nseg_ = nseg;
            nperf_ = nperf;

            wellRates().resize(nw * np, 0.0);

            currentControls().resize(nw);
            for(int iw = 0; iw < nw; ++iw) {
                currentControls()[iw] = well_controls_get_current(wells[iw]->wellControls());
            }

            for (int iw = 0; iw < nw; ++iw) {
                assert((wells[iw]->wellType() == INJECTOR) || (wells[iw]->wellType() == PRODUCER));
            }

            int start_segment = 0;
            int start_perforation = 0;

            perfPhaseRates().clear();
            perfPhaseRates().resize(nperf * np, 0.0);

            perfPress().clear();
            perfPress().resize(nperf, -1.0e100);

            segphaserates_.clear();
            segphaserates_.resize(nseg * np, 0.0);

            segpress_.clear();
            segpress_.resize(nseg, -1.0e100);


            for (int w = 0; w < nw; ++w) {
                assert((wells[w]->wellType() == INJECTOR) || (wells[w]->wellType() == PRODUCER));
                const WellControls* ctrl = wells[w]->wellControls();

                std::string well_name(wells[w]->name());
                // Initialize the wellMap_ here
                SegmentedMapentryType& wellMapEntry = segmentedWellMap_[well_name];
                wellMapEntry.well_number = w;
                wellMapEntry.start_segment = start_segment;
                wellMapEntry.number_of_segments = wells[w]->numberOfSegments();
                wellMapEntry.start_perforation = start_perforation;
                wellMapEntry.number_of_perforations = wells[w]->numberOfPerforations();

                top_segment_loc_[w] = start_segment;

                int start_perforation_segment = 0;
                wellMapEntry.start_perforation_segment.resize(wellMapEntry.number_of_segments);
                wellMapEntry.number_of_perforations_segment.resize(wellMapEntry.number_of_segments);

                for (int i = 0; i < wellMapEntry.number_of_segments; ++i) {
                    wellMapEntry.start_perforation_segment[i] = start_perforation_segment;
                    wellMapEntry.number_of_perforations_segment[i] = wells[w]->segmentPerforations()[i].size();
                    start_perforation_segment += wellMapEntry.number_of_perforations_segment[i];
                }
                assert(start_perforation_segment == wellMapEntry.number_of_perforations);


                if (well_controls_well_is_stopped(ctrl)) {
                    // 1. WellRates: 0
                    // 2. Bhp: assign bhp equal to bhp control, if applicable, otherwise
                    // assign equal to first perforation cell pressure.
                    if (well_controls_get_current_type(ctrl) == BHP) {
                        bhp()[w] = well_controls_get_current_target(ctrl);
                    } else {
                        const int first_cell = wells[0]->wellCells()[0];
                        bhp()[w] = state.pressure()[first_cell];
                    }
                    // 3. Thp: assign thp equal to thp control, if applicable,
                    // otherwise assign equal to bhp value.
                    if (well_controls_get_current_type(ctrl) == THP) {
                        thp()[w] = well_controls_get_current_target( ctrl );
                    } else {
                        thp()[w] = bhp()[w];
                    }
                    // 4. Perforation pressures and phase rates
                    // 5. Segment pressures and phase rates

                } else {
                    // Open Wells
                    // 1. Rates: initialize well rates to match controls if type is SURFACE_RATE. Otherwise, we
                    // cannot set the correct value here, so we aasign a small rate with the correct sign so that any
                    // logic depending on that sign will work as expected.
                    if (well_controls_get_current_type(ctrl) == SURFACE_RATE) {
                        const double rate_target = well_controls_get_current_target(ctrl);
                        const double * distr = well_controls_get_current_distr( ctrl );
                        for (int p = 0; p < np; ++p) {
                            wellRates()[np * w + p] = rate_target * distr[p];
                        }
                    } else {
                        const double small_rate = 1e-14;
                        const double sign = (wells[w]->wellType() == INJECTOR) ? 1.0 : -1.0;
                        for (int p = 0; p < np; ++p) {
                            wellRates()[np * w + p] = small_rate * sign;
                        }
                    }

                    // 2. Bhp:
                    if (well_controls_get_current_type(ctrl) == BHP) {
                        bhp()[w] = well_controls_get_current_target(ctrl);
                    } else {
                        const int first_cell = wells[w]->wellCells()[0];
                        const double safety_factor = (wells[w]->wellType() == INJECTOR) ? 1.01 : 0.99;
                        bhp()[w] = safety_factor* state.pressure()[first_cell];
                    }
                    // 3. Thp:
                    if (well_controls_get_current_type(ctrl) == THP) {
                        thp()[w] = well_controls_get_current_target(ctrl);
                    } else {
                        thp()[w] = bhp()[w];
                    }

                    // 4. Perf rates and pressures
                    int number_of_perforations = wellMapEntry.number_of_perforations;
                    for (int i = 0; i < number_of_perforations; ++i) {
                        for (int p = 0; p < np; ++p) {
                            perfPhaseRates()[np * (i + start_perforation) + p] = wellRates()[np * w + p] / double(number_of_perforations);
                        }
                        if (wells[w]->isMultiSegmented()) {
                            const double safety_factor = (wells[w]->wellType() == INJECTOR) ? 1.01 : 0.99;
                            perfPress()[i + start_perforation] = safety_factor * state.pressure()[wells[w]->wellCells()[i]];
                        } else {
                            perfPress()[i + start_perforation] = state.pressure()[wells[w]->wellCells()[i]];
                        }
                    }

                    // 5. Segment rates and pressures
                    int number_of_segments = wellMapEntry.number_of_segments;
                    // the seg_pressure is the same with the first pref_pressure. For the top segment, it is the same with bhp,
                    // when under bhp control.
                    // the seg_rates will related to the sum of the perforation rates, and also trying to keep consistent with the
                    // well rates. Most importantly, the segment rates of the top segment is the same with the well rates
                    segpress_[start_segment] = bhp()[w];
                    for (int i = 1; i < number_of_segments; ++i) {
                        /* for (int p = 0; p < np; ++p) {
                            segphaserates_[np * (i + start_segment) + p] = 0.;
                        } */
                        int first_perforation_segment = start_perforation + wellMapEntry.start_perforation_segment[i];
                        segpress_[i + start_segment] = perfPress()[first_perforation_segment];
                        // the segmnent pressure of the top segment should be the bhp
                    }

                    for (int p = 0; p < np; ++p) {
                        // std::vector<double> v_phase_rates(number_of_perforations);
                        // V v_perf_rates = V::Zero(number_of_perforations);
                        Eigen::VectorXd v_perf_rates(number_of_perforations);
                        for (int i = 0; i < number_of_perforations; ++i) {
                            v_perf_rates[i] = perfPhaseRates()[np * (i + start_perforation) + p];
                        }

                        Eigen::VectorXd v_segment_rates = wells[w]->wellOps().p2s_gather * v_perf_rates;

                        for (int i = 0; i < number_of_segments; ++i) {
                            segphaserates_[np * (i + start_segment) + p] = v_segment_rates[i];
                        }
                    }
                    // initialize the segmnet rates.
                    // it works in the analog way with the usual wells.

                    // How to initialize the perforation rates and the segment rates.?
                    // Perforation pressures can be set to the pressure of the corresponding grid cells?
                    // deviding the well rates by the number of the perforations
                    // then calculating the segment rate based on the rates for perforations and
                    // make sure the flow rate for the top segment is consistent with the well flow rates
                    // for pressure it is not that trival
                }

                start_segment += wellMapEntry.number_of_segments;
                start_perforation += wellMapEntry.number_of_perforations;

            }

            // assert(start_perforation == total_perforation);
            // assert(start_segment == total_segment);

            // Initialize current_controls_.
            // The controls set in the Wells object are treated as defaults,
            // and also used for initial values.
            currentControls().resize(nw);
            for (int w = 0; w < nw; ++w) {
                currentControls()[w] = well_controls_get_current(wells[w]->wellControls());
            }

            // initialize wells that have been there before
            // order can change so the mapping is based on the well names
            if ( !(prevState.segmentedWellMap().empty()) )
            {
                typedef typename SegmentedWellMapType::const_iterator const_iterator;
                const_iterator end_old = prevState.segmentedWellMap().end();

                for (int w = 0; w < nw; ++w) {
                    std::string well_name(wells[w]->name());
                    const_iterator it_old = prevState.segmentedWellMap().find(well_name);
                    const_iterator it_this = segmentedWellMap().find(well_name);

                    assert(it_this != segmentedWellMap().end()); // the current well must be present in the current well map

                    if (it_old != end_old) {
                        const int oldIndex = (*it_old).second.well_number;
                        const int newIndex = w;

                        // bhp
                        bhp()[newIndex] = prevState.bhp()[oldIndex];

                        // well rates
                        for( int i=0, idx=newIndex*np, oldidx=oldIndex*np; i<np; ++i, ++idx, ++oldidx )
                        {
                            wellRates()[ idx ] = prevState.wellRates()[ oldidx ];
                        }

                        const int num_seg_old_well = (*it_old).second.number_of_segments;
                        const int num_perf_old_well = (*it_old).second.number_of_perforations;

                        const int num_seg_this_well = (*it_this).second.number_of_segments;
                        const int num_perf_this_well = (*it_this).second.number_of_perforations;

                        // determing if the structure of the wells has been changed by comparing the number of segments and perforations
                        // may not be very safe.
                        // The strategy HAS to be changed later with experiments and analysis
                        if ((num_perf_old_well == num_perf_this_well) && (num_seg_old_well == num_seg_this_well)) {
                            const int old_start_perforation = (*it_old).second.start_perforation;
                            const int old_start_segment = (*it_old).second.start_segment;

                            const int this_start_perforation = (*it_this).second.start_perforation;
                            const int this_start_segment = (*it_this).second.start_segment;

                            // this is not good when the the well rates changed dramatically
                            for (int i = 0; i < num_seg_this_well * np; ++i) {
                                segphaserates_[this_start_segment * np + i] = prevState.segPhaseRates()[old_start_segment * np + i];
                            }

                            for (int i = 0; i < num_perf_this_well * np; ++i) {
                                perfPhaseRates()[this_start_perforation * np + i] = prevState.perfPhaseRates()[old_start_perforation * np + i];
                            }

                            // perf_pressures_
                            for (int i = 0; i < num_perf_this_well; ++i) {
                                // p
                                perfPress()[this_start_perforation + i] = prevState.perfPress()[old_start_perforation + i];
                            }

                            // segpress_
                            for (int i = 0; i < num_seg_this_well; ++i) {
                                // p
                                segpress_[this_start_segment + i] = prevState.segPress()[old_start_segment + i];
                            }

                            // current controls
                            const int old_control_index = prevState.currentControls()[ oldIndex ];
                            if (old_control_index < well_controls_get_num(wells[w]->wellControls())) {
                                // If the set of controls have changed, this may not be identical
                                // to the last control, but it must be a valid control.
                                currentControls()[ newIndex ] = old_control_index;
                            }
                        }

                        // else {
                            // deviding the well rates by the number of the perforations
                            // then calculating the segment rate based on the rates for perforations and
                            // make sure the flow rate for the top segment is consistent with the well flow rates
                            // for pressure it is not that trival
                        // }

                        // peforation rates
                        // segment rates
                        // It really depends on if the structures on the segments and perforations are changed.
                        // TODO: if it will be reasonable to assume that if the numbers of segments and perforations are same, then
                        // the structures of the wells are not changed.
                        // Obviously it is not true.

                        // for the perforation rates, it is Okay to calculate by deviding the well rates by the perforation numbers.
                        // Then the segment rates are calculated based on the perforation rates and the well rates.
                        // The segment rates of top segments should be the same with the well rates.
                    }
                }
            }

#if 0
            // Debugging output.
            std::cout << " output all the well state informations after initialization " << std::endl;
            const int nperf_total = numPerforations();
            const int nseg_total = numSegments();

            std::cout << " number of wells : " << nw << " nubmer of segments : " << nseg_total << std::endl;
            std::cout << " number of phase : " << np << " nubmer of perforations " << nperf_total << std::endl;

            std::cout << " bhps : " << std::endl;
            for (int i = 0; i < nw; ++i) {
                std::cout << bhp()[i] << std::endl;
            }

            std::cout << " thps : " << std::endl;

            for (int i = 0; i < nw; ++i) {
                std::cout << thp()[i] << std::endl;
            }

            std::cout << " well rates " << std::endl;
            for (int i = 0; i < nw; ++i) {
                std::cout << i;
                for (int p = 0; p < np; ++p) {
                    std::cout << " " << wellRates()[np * i + p];
                }
                std::cout << std::endl;
            }

            std::cout << " segment pressures and segment phase rates : " << std::endl;
            for (int i = 0; i < nseg_total; ++i) {
                std::cout << i << " " << segPress()[i];
                for (int p = 0; p < np; ++p) {
                    std::cout << " " << segPhaseRates()[np * i + p];
                }
                std::cout << std::endl;
            }

            std::cout << " perf pressures and pref phase rates : " << std::endl;
            for (int i = 0; i < nperf_total; ++i) {
                std::cout << i << " " << perfPress()[i];
                for (int p = 0; p < np; ++p) {
                    std::cout << " " << perfPhaseRates()[np * i + p];
                }
                std::cout << std::endl;
            }

            std::cout << " locations of the top segments : " << std::endl;
            for (int i = 0; i < nw; ++i) {
                std::cout << i << "  " << top_segment_loc_[i] << std::endl;
            }

            std::cout << " output all the information from the segmentedWellMap " << std::endl;

            for (auto iter = segmentedWellMap().begin(); iter != segmentedWellMap().end(); ++iter) {
                std::cout << " well name : " << iter->first << std::endl;
                const MapentryType &wellmapInfo = iter->second;
                std::cout << " well number : " << wellmapInfo.well_number << " start segment " << wellmapInfo.start_segment
                          << " number of segment : " << wellmapInfo.number_of_segments << std::endl;
                std::cout << " start perforation : " << wellmapInfo.start_perforation << " number of perforations : " << wellmapInfo.number_of_perforations << std::endl;
                const int nseg_well = wellmapInfo.number_of_segments;
                std::cout << "    start performation ofr each segment and number of perforation that each segment has" << std::endl;
                for (int i = 0; i < nseg_well; ++i) {
                    std::cout << " segment " << i << " start perforation " << wellmapInfo.start_perforation_segment[i]
                              << " number of perforations " << wellmapInfo.number_of_perforations_segment[i] << std::endl;
                }
            }
            std::cout << " output the well state right after intialization is DONE! " << std::endl;
#endif
        }


        std::vector<double>& segPress() { return segpress_; }
        const std::vector<double>& segPress() const { return segpress_; }

        std::vector<double>& segPhaseRates() { return segphaserates_; }
        const std::vector<double>& segPhaseRates() const { return segphaserates_; }

        const std::vector<int>& topSegmentLoc() const { return top_segment_loc_; };

        const SegmentedWellMapType& segmentedWellMap() const { return segmentedWellMap_; }
        SegmentedWellMapType& segmentedWellMap() { return segmentedWellMap_; }

        int numSegments() const { return nseg_; }
        int numPerforations() const { return nperf_; }

    private:
        // pressure for the segment nodes
        std::vector<double> segpress_;
        // phase rates for the segments
        std::vector<double> segphaserates_;
        // TODO: MIGHT NOT USE THE FOLLOWING VARIABLES AT THE
        // fractions for each segments (W, O, G)
        std::vector<double> segphasefrac_;
        // total flow rates for each segments, G_T
        std::vector<double> segtotalrate_;

        // the location of the top segments within the whole segment list
        // it is better in the Wells class if we have a class instead of
        // using a vector for all the wells
        std::vector<int> top_segment_loc_;

        SegmentedWellMapType segmentedWellMap_;

        int nseg_;
        int nperf_;
    };

} // namespace Opm


#endif // OPM_WELLSTATEMULTISEGMENT_HEADER_INCLUDE