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734eb76910
Fix bug when recalculating gaslift gradient
1783 lines
71 KiB
C++
1783 lines
71 KiB
C++
/*
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Copyright 2020 Equinor ASA.
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This file is part of the Open Porous Media project (OPM).
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OPM is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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OPM is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with OPM. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <config.h>
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#include <opm/simulators/wells/GasLiftSingleWellGeneric.hpp>
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#include <opm/input/eclipse/Schedule/GasLiftOpt.hpp>
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#include <opm/input/eclipse/Schedule/Schedule.hpp>
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#include <opm/input/eclipse/Schedule/Well/Well.hpp>
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#include <opm/simulators/utils/DeferredLogger.hpp>
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#include <opm/simulators/wells/GasLiftWellState.hpp>
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#include <opm/simulators/wells/GroupState.hpp>
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#include <opm/simulators/wells/WellState.hpp>
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#include <fmt/format.h>
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#include <cassert>
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#include <sstream>
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namespace Opm
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{
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GasLiftSingleWellGeneric::GasLiftSingleWellGeneric(DeferredLogger& deferred_logger,
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WellState& well_state,
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const GroupState& group_state,
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const Well& ecl_well,
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const SummaryState& summary_state,
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GasLiftGroupInfo& group_info,
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const PhaseUsage& phase_usage,
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const Schedule& schedule,
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const int report_step_idx,
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GLiftSyncGroups& sync_groups,
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const Parallel::Communication& comm,
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bool glift_debug)
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: GasLiftCommon(well_state, group_state, deferred_logger, comm, glift_debug)
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, ecl_well_ {ecl_well}
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, summary_state_ {summary_state}
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, group_info_ {group_info}
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, phase_usage_ {phase_usage}
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, sync_groups_ {sync_groups}
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, controls_ {ecl_well_.productionControls(summary_state_)}
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, debug_limit_increase_decrease_ {false}
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{
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this->well_name_ = ecl_well_.name();
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const GasLiftOpt& glo = schedule.glo(report_step_idx);
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// NOTE: According to LIFTOPT, item 1:
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// "Increment size for lift gas injection rate. Lift gas is
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// allocated to individual wells in whole numbers of the increment
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// size. If gas lift optimization is no longer required, it can be
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// turned off by entering a zero or negative number."
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// NOTE: This condition was checked in doGasLiftOptimize() in StandardWell
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// so it can be assumed that increment_ > 0
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this->increment_ = glo.gaslift_increment();
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assert(this->increment_ > 0);
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// NOTE: The manual (see LIFTOPT, item 2) does not mention
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// any default value or restrictions on the economic gradient.
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// TODO: The value of the gradient would most likely be a positive
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// number. Should we warn or fail on a negative value?
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// A negative value for the economic gradient would mean that
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// the oil production is decreasing with increased liftgas
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// injection (which seems strange)
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this->eco_grad_ = glo.min_eco_gradient();
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gl_well_ = &glo.well(this->well_name_);
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}
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/****************************************
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* Public methods in alphabetical order
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****************************************/
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// NOTE: Used from GasLiftStage2
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std::optional<GasLiftSingleWellGeneric::GradInfo>
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GasLiftSingleWellGeneric::calcIncOrDecGradient( double oil_rate,
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double gas_rate,
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double water_rate,
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double alq,
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const std::string& gr_name_dont_limit,
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bool increase,
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bool debug_output
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) const
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{
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auto [new_alq_opt, alq_is_limited] = addOrSubtractAlqIncrement_(alq, increase);
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// TODO: What to do if ALQ is limited and new_alq != alq?
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if (!new_alq_opt)
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return std::nullopt;
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double new_alq = *new_alq_opt;
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auto delta_alq = new_alq - alq;
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if (checkGroupALQrateExceeded(delta_alq, gr_name_dont_limit))
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return std::nullopt;
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if (auto bhp = computeBhpAtThpLimit_(new_alq, debug_output)) {
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auto [new_bhp, bhp_is_limited] = getBhpWithLimit_(*bhp);
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// TODO: What to do if BHP is limited?
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auto rates = computeWellRates_(new_bhp, bhp_is_limited, debug_output);
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const auto ratesLimited = getLimitedRatesFromRates_(rates);
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BasicRates oldrates = {oil_rate, gas_rate, water_rate, false};
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const auto new_rates = updateRatesToGroupLimits_(oldrates, ratesLimited, gr_name_dont_limit);
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if (!increase && new_rates.oil < 0) {
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return std::nullopt;
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}
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auto grad = calcEcoGradient_(oil_rate, new_rates.oil, gas_rate, new_rates.gas, increase);
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return GradInfo(grad,
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new_rates.oil,
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new_rates.oil_is_limited,
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new_rates.gas,
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new_rates.gas_is_limited,
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new_rates.water,
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new_rates.water_is_limited,
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new_alq,
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alq_is_limited);
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} else {
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return std::nullopt;
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}
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}
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std::unique_ptr<GasLiftWellState>
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GasLiftSingleWellGeneric::runOptimize(const int iteration_idx)
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{
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std::unique_ptr<GasLiftWellState> state;
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if (this->optimize_) {
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if (this->debug_limit_increase_decrease_) {
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state = runOptimize1_();
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} else {
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state = runOptimize2_();
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}
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if (state) {
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// NOTE: that state->increase() returns a std::optional<bool>, if
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// this is std::nullopt it means that we was not able to change ALQ
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// (either increase or decrease)
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if (state->increase()) { // ALQ changed..
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double alq = state->alq();
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if (this->debug)
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logSuccess_(alq, iteration_idx);
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this->well_state_.setALQ(this->well_name_, alq);
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const auto& pu = this->phase_usage_;
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std::vector<double> well_pot(pu.num_phases, 0.0);
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if (pu.phase_used[BlackoilPhases::PhaseIndex::Liquid])
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well_pot[pu.phase_pos[BlackoilPhases::PhaseIndex::Liquid]] = state->oilRate();
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if (pu.phase_used[BlackoilPhases::PhaseIndex::Aqua])
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well_pot[pu.phase_pos[BlackoilPhases::PhaseIndex::Aqua]] = state->waterRate();
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if (pu.phase_used[BlackoilPhases::PhaseIndex::Vapour])
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well_pot[pu.phase_pos[BlackoilPhases::PhaseIndex::Vapour]] = state->gasRate();
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this->well_state_[this->well_name_].well_potentials = well_pot;
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}
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}
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}
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return state;
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}
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/****************************************
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* Protected methods in alphabetical order
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****************************************/
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std::pair<std::optional<double>, bool>
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GasLiftSingleWellGeneric::addOrSubtractAlqIncrement_(double alq, bool increase) const
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{
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bool limited = false;
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double orig_alq = alq;
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if (increase) {
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alq += this->increment_;
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// NOTE: if max_alq_ was defaulted in WLIFTOPT, item 3, it has
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// already been set to the largest value in the VFP table in
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// the contructor of GasLiftSingleWell
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if (alq > this->max_alq_) {
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alq = this->max_alq_;
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limited = true;
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}
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} else { // we are decreasing ALQ
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alq -= this->increment_;
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if (this->min_alq_ > 0) {
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// According to WLIFTOPT item 5: If a positive value is
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// specified (min_alq_), the well is allocated at least that amount
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// of lift gas, unless the well is unable to flow with
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// that rate of lift gas injection, or unless the well can
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// already meet one of its own rate limits before
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// receiving its minimum lift gas rate.
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if (alq < this->min_alq_) {
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alq = this->min_alq_;
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limited = true;
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}
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} else {
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if (alq < 0) {
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alq = 0.0;
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limited = true;
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}
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}
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}
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std::optional<double> alq_opt {alq};
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// If we were not able to change ALQ (to within rounding error), we
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// return std::nullopt
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if (limited && checkALQequal_(orig_alq, alq))
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alq_opt = std::nullopt;
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return {alq_opt, limited};
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}
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double
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GasLiftSingleWellGeneric::calcEcoGradient_(
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double oil_rate, double new_oil_rate, double gas_rate, double new_gas_rate, bool increase) const
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{
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auto dqo = new_oil_rate - oil_rate;
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auto dqg = new_gas_rate - gas_rate;
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// TODO: Should the gas rate term in the denominator be subject to the constraint:
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//
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// alpha_g_ * dqg >= 0.0
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//
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// ?
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auto gradient = (this->alpha_w_ * dqo) / (this->increment_ + this->alpha_g_ * dqg);
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// TODO: Should we do any error checks on the calculation of the
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// gradient?
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if (!increase)
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gradient = -gradient;
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return gradient;
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}
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bool
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GasLiftSingleWellGeneric::checkALQequal_(double alq1, double alq2) const
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{
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return std::fabs(alq1 - alq2) < (this->increment_ * ALQ_EPSILON);
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}
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bool
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GasLiftSingleWellGeneric::checkGroupTargetsViolated(const BasicRates& rates, const BasicRates& new_rates) const
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{
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const auto& pairs = this->group_info_.getWellGroups(this->well_name_);
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for (const auto& [group_name, efficiency] : pairs) {
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for (const auto rate_type : {Rate::oil, Rate::gas, Rate::water, Rate::liquid}) {
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auto target_opt = this->group_info_.getTarget(rate_type, group_name);
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if (target_opt) {
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auto delta_rate = new_rates[rate_type] - rates[rate_type];
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auto new_group_rate = this->group_info_.getPotential(rate_type, group_name) + efficiency * delta_rate;
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if (new_group_rate > *target_opt) {
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if (this->debug) {
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const std::string msg
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= fmt::format("Group {} : {} rate {} exceeds target {}. Stopping iteration",
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group_name,
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GasLiftGroupInfo::rateToString(rate_type),
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new_group_rate,
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*target_opt);
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displayDebugMessage_(msg);
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}
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return true;
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}
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}
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}
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}
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return false;
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}
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bool
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GasLiftSingleWellGeneric::checkInitialALQmodified_(double alq, double initial_alq) const
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{
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if (checkALQequal_(alq, initial_alq)) {
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return false;
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} else {
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const std::string msg = fmt::format("initial ALQ changed from {} "
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"to {} before iteration starts..",
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initial_alq,
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alq);
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displayDebugMessage_(msg);
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return true;
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}
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}
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std::pair<std::optional<double>,double>
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GasLiftSingleWellGeneric::
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computeConvergedBhpAtThpLimitByMaybeIncreasingALQ_() const
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{
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auto alq = this->orig_alq_;
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double new_alq = alq;
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std::optional<double> bhp;
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while ((alq < this->max_alq_) || checkALQequal_(alq, this->max_alq_)) {
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if (bhp = computeBhpAtThpLimit_(alq); bhp) {
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new_alq = alq;
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break;
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}
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alq += this->increment_;
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}
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return {bhp, new_alq};
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}
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std::pair<std::optional<GasLiftSingleWellGeneric::BasicRates>, double>
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GasLiftSingleWellGeneric::computeInitialWellRates_() const
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{
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std::optional<BasicRates> rates;
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double initial_alq = this->orig_alq_;
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// auto alq = initial_alq;
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// if (auto bhp = computeBhpAtThpLimit_(this->orig_alq_); bhp) {
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if (auto [bhp, alq] = computeConvergedBhpAtThpLimitByMaybeIncreasingALQ_(); bhp) {
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{
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const std::string msg = fmt::format("computed initial bhp {} given thp limit and given alq {}", *bhp, alq);
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displayDebugMessage_(msg);
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}
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initial_alq = alq;
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auto [new_bhp, bhp_is_limited] = getBhpWithLimit_(*bhp);
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rates = computeWellRates_(new_bhp, bhp_is_limited);
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if (rates) {
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const std::string msg = fmt::format("computed initial well potentials given bhp, "
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"oil: {}, gas: {}, water: {}",
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rates->oil,
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rates->gas,
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rates->water);
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displayDebugMessage_(msg);
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}
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}
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else {
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displayDebugMessage_("Aborting optimization.");
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}
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return {rates, initial_alq};
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}
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std::optional<GasLiftSingleWellGeneric::LimitedRates>
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GasLiftSingleWellGeneric::computeLimitedWellRatesWithALQ_(double alq) const
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{
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std::optional<LimitedRates> limited_rates;
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if (auto rates = computeWellRatesWithALQ_(alq); rates) {
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limited_rates = getLimitedRatesFromRates_(*rates);
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}
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return limited_rates;
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}
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std::optional<GasLiftSingleWellGeneric::BasicRates>
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GasLiftSingleWellGeneric::computeWellRatesWithALQ_(double alq) const
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{
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std::optional<BasicRates> rates;
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auto bhp_opt = computeBhpAtThpLimit_(alq);
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if (bhp_opt) {
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auto [bhp, bhp_is_limited] = getBhpWithLimit_(*bhp_opt);
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rates = computeWellRates_(bhp, bhp_is_limited);
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}
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return rates;
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}
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void
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GasLiftSingleWellGeneric::debugCheckNegativeGradient_(double grad,
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double alq,
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double new_alq,
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double oil_rate,
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double new_oil_rate,
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double gas_rate,
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double new_gas_rate,
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bool increase) const
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{
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{
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const std::string msg = fmt::format("calculating gradient: "
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"new_oil_rate = {}, oil_rate = {}, grad = {}",
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new_oil_rate,
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oil_rate,
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grad);
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displayDebugMessage_(msg);
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}
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if (grad < 0) {
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const std::string msg = fmt::format("negative {} gradient detected ({}) : "
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"alq: {}, new_alq: {}, "
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"oil_rate: {}, new_oil_rate: {}, gas_rate: {}, new_gas_rate: {}",
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(increase ? "incremental" : "decremental"),
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grad,
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alq,
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new_alq,
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oil_rate,
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new_oil_rate,
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gas_rate,
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new_gas_rate);
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displayDebugMessage_(msg);
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}
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}
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void
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GasLiftSingleWellGeneric::debugShowAlqIncreaseDecreaseCounts_()
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{
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auto inc_count = this->well_state_.gliftGetAlqIncreaseCount(this->well_name_);
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auto dec_count = this->well_state_.gliftGetAlqDecreaseCount(this->well_name_);
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const std::string msg = fmt::format("ALQ increase/decrease count : {}/{}", inc_count, dec_count);
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displayDebugMessage_(msg);
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}
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void
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GasLiftSingleWellGeneric::debugShowBhpAlqTable_()
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{
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double alq = 0.0;
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const std::string fmt_fmt1 {"{:^12s} {:^12s} {:^12s} {:^12s}"};
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const std::string fmt_fmt2 {"{:>12.5g} {:>12.5g} {:>12.5g} {:>12.5g}"};
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const std::string header = fmt::format(fmt_fmt1, "ALQ", "BHP", "oil", "gas");
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displayDebugMessage_(header);
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auto max_it = 50;
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auto it = 1;
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while (alq <= (this->max_alq_ + this->increment_)) {
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auto bhp_at_thp_limit = computeBhpAtThpLimit_(alq);
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if (!bhp_at_thp_limit) {
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const std::string msg = fmt::format("Failed to get converged potentials "
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"for ALQ = {}. Skipping.",
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alq);
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displayDebugMessage_(msg);
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} else {
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auto [bhp, bhp_is_limited] = getBhpWithLimit_(*bhp_at_thp_limit);
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auto rates = computeWellRates_(bhp, bhp_is_limited, /*debug_out=*/false);
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const std::string msg = fmt::format(fmt_fmt2, alq, bhp, rates.oil, rates.gas);
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displayDebugMessage_(msg);
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}
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alq += this->increment_;
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if (it > max_it) {
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const std::string msg = fmt::format("ALQ table : max iterations {} reached. Stopping iteration.", max_it);
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displayDebugMessage_(msg);
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break;
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}
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it++;
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}
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}
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void
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GasLiftSingleWellGeneric::debugShowLimitingTargets_(const LimitedRates& rates) const
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{
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if (rates.limited()) {
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if (rates.oil_is_limited) {
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const std::string msg = fmt::format("oil rate {} is limited by {} target",
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rates.oil,
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GasLiftGroupInfo::rateToString(*(rates.oil_limiting_target)));
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displayDebugMessage_(msg);
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}
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if (rates.gas_is_limited) {
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const std::string msg = fmt::format("gas rate {} is limited by GRAT target", rates.gas);
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displayDebugMessage_(msg);
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}
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if (rates.water_is_limited) {
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const std::string msg = fmt::format("water rate {} is limited by {} target",
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rates.water,
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GasLiftGroupInfo::rateToString(*(rates.water_limiting_target)));
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displayDebugMessage_(msg);
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}
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} else {
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displayDebugMessage_("no rates are currently limited by a target");
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}
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}
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void
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GasLiftSingleWellGeneric::debugShowProducerControlMode() const
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{
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const int well_index = this->well_state_.index(this->well_name_).value();
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const Well::ProducerCMode& control_mode = this->well_state_.well(well_index).production_cmode;
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const std::string msg = fmt::format("Current control mode is: {}", WellProducerCMode2String(control_mode));
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displayDebugMessage_(msg);
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}
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void
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GasLiftSingleWellGeneric::debugShowStartIteration_(double alq, bool increase, double oil_rate)
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{
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const std::string msg = fmt::format(
|
|
"starting {} iteration, ALQ = {}, oilrate = {}", (increase ? "increase" : "decrease"), alq, oil_rate);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
|
|
void
|
|
GasLiftSingleWellGeneric::debugShowTargets_()
|
|
{
|
|
if (this->controls_.hasControl(Well::ProducerCMode::ORAT)) {
|
|
auto target = this->controls_.oil_rate;
|
|
const std::string msg = fmt::format("has ORAT control with target {}", target);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
if (this->controls_.hasControl(Well::ProducerCMode::GRAT)) {
|
|
auto target = this->controls_.gas_rate;
|
|
const std::string msg = fmt::format("has GRAT control with target {}", target);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
if (this->controls_.hasControl(Well::ProducerCMode::LRAT)) {
|
|
auto target = this->controls_.liquid_rate;
|
|
const std::string msg = fmt::format("has LRAT control with target {}", target);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
}
|
|
|
|
void
|
|
GasLiftSingleWellGeneric::displayDebugMessage_(const std::string& msg) const
|
|
{
|
|
|
|
if (this->debug) {
|
|
const std::string message = fmt::format("Well {} : {}", this->well_name_, msg);
|
|
logMessage_(/*prefix=*/"GLIFT", message);
|
|
}
|
|
}
|
|
|
|
void
|
|
GasLiftSingleWellGeneric::displayWarning_(const std::string& msg)
|
|
{
|
|
const std::string message = fmt::format("WELL {} : {}", this->well_name_, msg);
|
|
logMessage_(/*prefix=*/"GLIFT", msg, MessageType::WARNING);
|
|
}
|
|
|
|
std::pair<double, bool>
|
|
GasLiftSingleWellGeneric::getBhpWithLimit_(double bhp) const
|
|
{
|
|
bool limited = false;
|
|
if (this->controls_.hasControl(Well::ProducerCMode::BHP)) {
|
|
auto limit = this->controls_.bhp_limit;
|
|
if (bhp < limit) {
|
|
bhp = limit;
|
|
limited = true;
|
|
}
|
|
}
|
|
return {bhp, limited};
|
|
}
|
|
|
|
|
|
// TODO: what if the gas_rate_target_ has been defaulted
|
|
// (i.e. value == 0, meaning: "No limit") but the
|
|
// oil_rate_target_ has not been defaulted ?
|
|
// If the new_oil_rate exceeds the oil_rate_target_ it is cut back,
|
|
// but the same cut-back will not happen for the new_gas_rate
|
|
// Seems like an inconsistency, since alq should in this
|
|
// case also be adjusted (to the smaller value that would
|
|
// give oil target rate) but then the gas rate would also be smaller?
|
|
// The effect of not reducing the gas rate (if it should be
|
|
// reduced?) is that a too large value is used in the
|
|
// computation of the economic gradient making the gradient
|
|
// smaller than it should be since the term appears in the denominator.
|
|
std::pair<double, bool>
|
|
GasLiftSingleWellGeneric::getGasRateWithLimit_(const BasicRates& rates) const
|
|
{
|
|
auto [rate, target_type] = getRateWithLimit_(Rate::gas, rates);
|
|
bool limited = target_type.has_value();
|
|
return {rate, limited};
|
|
}
|
|
|
|
// NOTE: If the computed oil rate is larger than the target
|
|
// rate of the well, we reduce it to the target rate. This
|
|
// will make the economic gradient smaller than it would be
|
|
// if we did not reduce the rate, and it is less
|
|
// likely that the current gas lift increment will be
|
|
// accepted.
|
|
// TODO: If it still is accepted, we should ideally reduce the alq
|
|
// also since we also reduced the rate. This might involve
|
|
// some sort of iteration though..
|
|
std::pair<double, bool>
|
|
GasLiftSingleWellGeneric::getOilRateWithLimit_(const BasicRates& rates) const
|
|
{
|
|
auto [rate, target_type] = getRateWithLimit_(Rate::oil, rates);
|
|
bool limited = target_type.has_value();
|
|
return {rate, limited};
|
|
}
|
|
|
|
std::pair<double, std::optional<GasLiftSingleWellGeneric::Rate>>
|
|
GasLiftSingleWellGeneric::getOilRateWithLimit2_(const BasicRates& rates) const
|
|
{
|
|
return getRateWithLimit_(Rate::oil, rates);
|
|
}
|
|
|
|
std::pair<double, bool>
|
|
GasLiftSingleWellGeneric::getWaterRateWithLimit_(const BasicRates& rates) const
|
|
{
|
|
auto [rate, target_type] = getRateWithLimit_(Rate::water, rates);
|
|
bool limited = target_type.has_value();
|
|
return {rate, limited};
|
|
}
|
|
|
|
std::pair<double, std::optional<GasLiftSingleWellGeneric::Rate>>
|
|
GasLiftSingleWellGeneric::getWaterRateWithLimit2_(const BasicRates& rates) const
|
|
{
|
|
return getRateWithLimit_(Rate::water, rates);
|
|
}
|
|
|
|
double
|
|
GasLiftSingleWellGeneric::getRate_(Rate rate, const BasicRates& rates) const
|
|
{
|
|
switch (rate) {
|
|
case Rate::oil:
|
|
return rates.oil;
|
|
case Rate::gas:
|
|
return rates.gas;
|
|
case Rate::water:
|
|
return rates.water;
|
|
case Rate::liquid:
|
|
return rates.oil + rates.water;
|
|
default:
|
|
// Need this to avoid compiler warning : control reaches end of non-void function
|
|
throw std::runtime_error("This should not happen");
|
|
}
|
|
}
|
|
|
|
double
|
|
GasLiftSingleWellGeneric::getProductionTarget_(Rate rate) const
|
|
{
|
|
switch (rate) {
|
|
case Rate::oil:
|
|
return this->controls_.oil_rate;
|
|
case Rate::gas:
|
|
return this->controls_.gas_rate;
|
|
case Rate::water:
|
|
return this->controls_.water_rate;
|
|
case Rate::liquid:
|
|
return this->controls_.liquid_rate;
|
|
default:
|
|
// Need this to avoid compiler warning : control reaches end of non-void function
|
|
throw std::runtime_error("This should not happen");
|
|
}
|
|
}
|
|
|
|
std::pair<double, std::optional<GasLiftSingleWellGeneric::Rate>>
|
|
GasLiftSingleWellGeneric::getRateWithLimit_(Rate rate_type, const BasicRates& rates) const
|
|
{
|
|
double new_rate = getRate_(rate_type, rates);
|
|
// If "target_type" is empty at the end of this method, it means the rate
|
|
// was not limited. Otherwise, target_type gives the reason (the type of target)
|
|
// for why the rate was limited.
|
|
std::optional<Rate> target_type;
|
|
|
|
if (hasProductionControl_(rate_type)) {
|
|
auto target = getProductionTarget_(rate_type);
|
|
if (new_rate > target) {
|
|
const std::string msg = fmt::format("limiting {} rate to target: "
|
|
"computed rate: {}, target: {}",
|
|
GasLiftGroupInfo::rateToString(rate_type),
|
|
new_rate,
|
|
target);
|
|
displayDebugMessage_(msg);
|
|
new_rate = target;
|
|
target_type = rate_type;
|
|
}
|
|
}
|
|
if (((rate_type == Rate::oil) || (rate_type == Rate::water)) && hasProductionControl_(Rate::liquid)) {
|
|
double rate2;
|
|
if (rate_type == Rate::oil) {
|
|
rate2 = getRate_(Rate::water, rates);
|
|
} else {
|
|
rate2 = getRate_(Rate::oil, rates);
|
|
}
|
|
// Note: Since "new_rate" was first updated for ORAT or WRAT, see first "if"
|
|
// statement in the method, the rate is limited due to LRAT only if
|
|
// it becomes less than the rate limited by a WRAT or ORAT target..
|
|
double liq_rate = new_rate + rate2;
|
|
|
|
auto liq_target = getProductionTarget_(Rate::liquid);
|
|
if (liq_rate > liq_target) {
|
|
double fraction = new_rate / liq_rate;
|
|
// NOTE: since
|
|
// fraction * liq_rate = new_rate,
|
|
// we must have
|
|
// fraction * liq_target < new_rate
|
|
// since
|
|
// liq_target < liq_rate
|
|
// therefore new_rate will become less than it original was and
|
|
// limited = true.
|
|
new_rate = fraction * liq_target;
|
|
target_type = Rate::liquid;
|
|
const std::string msg = fmt::format("limiting {} rate to {} due to LRAT target: "
|
|
"computed LRAT: {}, target LRAT: {}",
|
|
GasLiftGroupInfo::rateToString(rate_type),
|
|
new_rate,
|
|
liq_rate,
|
|
liq_target);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
}
|
|
// TODO: Also check RESV target?
|
|
return {new_rate, target_type};
|
|
}
|
|
|
|
std::pair<double, bool>
|
|
GasLiftSingleWellGeneric::getOilRateWithGroupLimit_(double new_oil_rate, double oil_rate, const std::string& gr_name_dont_limit) const
|
|
{
|
|
[[maybe_unused]] auto [rate, gr_name, efficiency] = getRateWithGroupLimit_(Rate::oil, new_oil_rate, oil_rate, gr_name_dont_limit);
|
|
bool limited = gr_name != nullptr;
|
|
return {rate, limited};
|
|
}
|
|
|
|
std::pair<double, bool>
|
|
GasLiftSingleWellGeneric::getGasRateWithGroupLimit_(double new_gas_rate, double gas_rate, const std::string& gr_name_dont_limit) const
|
|
{
|
|
[[maybe_unused]] auto [rate, gr_name, efficiency] = getRateWithGroupLimit_(Rate::gas, new_gas_rate, gas_rate, gr_name_dont_limit);
|
|
bool limited = gr_name != nullptr;
|
|
return {rate, limited};
|
|
}
|
|
|
|
std::pair<double, bool>
|
|
GasLiftSingleWellGeneric::getWaterRateWithGroupLimit_(double new_water_rate, double water_rate, const std::string& gr_name_dont_limit) const
|
|
{
|
|
[[maybe_unused]] auto [rate, gr_name, efficiency] = getRateWithGroupLimit_(Rate::water, new_water_rate, water_rate, gr_name_dont_limit);
|
|
bool limited = gr_name != nullptr;
|
|
return {rate, limited};
|
|
}
|
|
|
|
std::tuple<double, double, bool, bool>
|
|
GasLiftSingleWellGeneric::getLiquidRateWithGroupLimit_(const double new_oil_rate,
|
|
const double oil_rate,
|
|
const double new_water_rate,
|
|
const double water_rate,
|
|
const std::string& gr_name_dont_limit) const
|
|
{
|
|
auto liquid_rate = oil_rate + water_rate;
|
|
auto new_liquid_rate = new_oil_rate + new_water_rate;
|
|
auto [liquid_rate_limited, group_name, efficiency]
|
|
= getRateWithGroupLimit_(Rate::liquid, new_liquid_rate, liquid_rate, gr_name_dont_limit);
|
|
bool limited = group_name != nullptr;
|
|
if (limited) {
|
|
// the oil, gas, and water cases can be handled directly by
|
|
// getRateWithGroupLimit_() above. However, for the liquid case
|
|
// we must do some postprocessing. I chose to include it here
|
|
// instead of cluttering up getRateWithGroupLimit_() with this
|
|
// special case.
|
|
double delta_water = new_water_rate - water_rate;
|
|
double delta_oil = new_oil_rate - oil_rate;
|
|
|
|
double gr_water_rate = this->group_info_.waterRate(*group_name);
|
|
double gr_oil_rate = this->group_info_.oilRate(*group_name);
|
|
|
|
// NOTE: these rates are too large according to the limited liquid rate
|
|
// but it does not matter since we are only using them to calculate
|
|
// the fraction of the liquid corresponding to the oil phase
|
|
double new_gr_water_rate = gr_water_rate + efficiency * delta_water;
|
|
double new_gr_oil_rate = gr_oil_rate + efficiency * delta_oil;
|
|
double new_gr_liquid_rate = new_gr_water_rate + new_gr_oil_rate;
|
|
|
|
double oil_fraction = new_gr_oil_rate / new_gr_liquid_rate;
|
|
double delta_liquid = liquid_rate_limited - liquid_rate;
|
|
auto limited_oil_rate = oil_rate + oil_fraction * delta_liquid;
|
|
auto limited_water_rate = water_rate + (1.0 - oil_fraction) * delta_liquid;
|
|
return {limited_oil_rate, limited_water_rate, limited, limited};
|
|
}
|
|
return {new_oil_rate, new_water_rate, limited, limited};
|
|
}
|
|
|
|
std::tuple<double, const std::string*, double>
|
|
GasLiftSingleWellGeneric::getRateWithGroupLimit_(Rate rate_type, const double new_rate, const double old_rate, const std::string& gr_name_dont_limit) const
|
|
{
|
|
const double delta_rate = new_rate - old_rate;
|
|
if (delta_rate > 0) {
|
|
// It is required that the production rate for a given group is
|
|
// is less than or equal to its target rate.
|
|
// Then it only makes sense to check if the group target is exceeded
|
|
// if delta_rate > 0
|
|
const auto& pairs = this->group_info_.getWellGroups(this->well_name_);
|
|
double limited_rate = new_rate;
|
|
double gr_target, new_gr_rate, efficiency;
|
|
const std::string* group_name = nullptr;
|
|
for (const auto& [group_name_temp, efficiency_temp] : pairs) {
|
|
// in stage 2 we don't want to limit the rate to the group
|
|
// target we are trying to redistribute the gaslift within
|
|
if (gr_name_dont_limit == group_name_temp) {
|
|
continue;
|
|
}
|
|
|
|
auto gr_target_opt = this->group_info_.getTarget(rate_type, group_name_temp);
|
|
if (gr_target_opt) {
|
|
double gr_target_temp = *gr_target_opt;
|
|
double gr_rate_temp = this->group_info_.getRate(rate_type, group_name_temp);
|
|
if (gr_rate_temp > gr_target_temp) {
|
|
if (this->debug) {
|
|
debugInfoGroupRatesExceedTarget(rate_type, group_name_temp, gr_rate_temp, gr_target_temp);
|
|
}
|
|
group_name = &group_name_temp;
|
|
efficiency = efficiency_temp;
|
|
limited_rate = old_rate;
|
|
gr_target = gr_target_temp;
|
|
new_gr_rate = gr_rate_temp;
|
|
break;
|
|
}
|
|
double new_gr_rate_temp = gr_rate_temp + efficiency_temp * delta_rate;
|
|
if (new_gr_rate_temp > gr_target_temp) {
|
|
double limited_rate_temp = old_rate + (gr_target_temp - gr_rate_temp) / efficiency_temp;
|
|
if (limited_rate_temp < limited_rate) {
|
|
group_name = &group_name_temp;
|
|
efficiency = efficiency_temp;
|
|
limited_rate = limited_rate_temp;
|
|
gr_target = gr_target_temp;
|
|
new_gr_rate = new_gr_rate_temp;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (group_name) {
|
|
if (this->debug) {
|
|
const std::string msg = fmt::format("limiting {} rate from {} to {} to meet group target {} "
|
|
"for group {}. Computed group rate was: {}",
|
|
GasLiftGroupInfo::rateToString(rate_type),
|
|
new_rate,
|
|
limited_rate,
|
|
gr_target,
|
|
*group_name,
|
|
new_gr_rate);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
return {limited_rate, group_name, efficiency};
|
|
}
|
|
}
|
|
return {new_rate, /*group_name =*/nullptr, /*efficiency dummy value*/ 0.0};
|
|
}
|
|
|
|
|
|
std::pair<std::optional<GasLiftSingleWellGeneric::LimitedRates>, double>
|
|
GasLiftSingleWellGeneric::getInitialRatesWithLimit_() const
|
|
{
|
|
std::optional<LimitedRates> limited_rates;
|
|
double initial_alq = this->orig_alq_;
|
|
if (auto [rates, alq] = computeInitialWellRates_(); rates) {
|
|
if (this->debug) {
|
|
displayDebugMessage_("Maybe limiting initial rates before optimize loop..");
|
|
}
|
|
auto temp_rates = getLimitedRatesFromRates_(*rates);
|
|
BasicRates old_rates = getWellStateRates_();
|
|
limited_rates = updateRatesToGroupLimits_(old_rates, temp_rates);
|
|
initial_alq = alq;
|
|
}
|
|
return {limited_rates, initial_alq};
|
|
}
|
|
|
|
GasLiftSingleWellGeneric::LimitedRates
|
|
GasLiftSingleWellGeneric::getLimitedRatesFromRates_(const BasicRates& rates) const
|
|
{
|
|
auto [oil_rate, oil_limiting_target] = getOilRateWithLimit2_(rates);
|
|
auto [gas_rate, gas_is_limited] = getGasRateWithLimit_(rates);
|
|
auto [water_rate, water_limiting_target] = getWaterRateWithLimit2_(rates);
|
|
bool oil_is_limited = oil_limiting_target.has_value();
|
|
bool water_is_limited = water_limiting_target.has_value();
|
|
return LimitedRates {oil_rate,
|
|
gas_rate,
|
|
water_rate,
|
|
oil_is_limited,
|
|
gas_is_limited,
|
|
water_is_limited,
|
|
rates.bhp_is_limited,
|
|
oil_limiting_target,
|
|
water_limiting_target};
|
|
}
|
|
|
|
GasLiftSingleWellGeneric::BasicRates
|
|
GasLiftSingleWellGeneric::getWellStateRates_() const
|
|
{
|
|
const int well_index = this->well_state_.index(this->well_name_).value();
|
|
const auto& pu = this->phase_usage_;
|
|
const auto& ws = this->well_state_.well(well_index);
|
|
const auto& wrate = ws.well_potentials;
|
|
|
|
const auto oil_rate = pu.phase_used[Oil] ? wrate[pu.phase_pos[Oil]] : 0.0;
|
|
|
|
const auto gas_rate = pu.phase_used[Gas] ? wrate[pu.phase_pos[Gas]] : 0.0;
|
|
|
|
const auto water_rate = pu.phase_used[Water] ? wrate[pu.phase_pos[Water]] : 0.0;
|
|
if (this->debug) {
|
|
const std::string msg = fmt::format("Initial surface rates: oil : {}, "
|
|
"gas : {}, water : {}",
|
|
oil_rate,
|
|
gas_rate,
|
|
water_rate);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
return BasicRates {oil_rate, water_rate, gas_rate, /*bhp_is_limited=*/false};
|
|
}
|
|
|
|
|
|
bool
|
|
GasLiftSingleWellGeneric::hasProductionControl_(Rate rate) const
|
|
{
|
|
switch (rate) {
|
|
case Rate::oil:
|
|
return this->controls_.hasControl(Well::ProducerCMode::ORAT);
|
|
case Rate::gas:
|
|
return this->controls_.hasControl(Well::ProducerCMode::GRAT);
|
|
case Rate::water:
|
|
return this->controls_.hasControl(Well::ProducerCMode::WRAT);
|
|
case Rate::liquid:
|
|
return this->controls_.hasControl(Well::ProducerCMode::LRAT);
|
|
default:
|
|
// Need this to avoid compiler warning : control reaches end of non-void function
|
|
throw std::runtime_error("This should not happen");
|
|
}
|
|
}
|
|
|
|
|
|
std::pair<GasLiftSingleWellGeneric::LimitedRates, double>
|
|
GasLiftSingleWellGeneric::increaseALQtoPositiveOilRate_(double alq, const LimitedRates& orig_rates) const
|
|
{
|
|
bool stop_iteration = false;
|
|
double temp_alq = alq;
|
|
// use the copy constructor to only copy the rates
|
|
BasicRates rates = orig_rates;
|
|
while (!stop_iteration) {
|
|
temp_alq += this->increment_;
|
|
if (temp_alq > this->max_alq_)
|
|
break;
|
|
auto temp_rates = computeWellRatesWithALQ_(temp_alq);
|
|
if (!temp_rates)
|
|
break;
|
|
alq = temp_alq;
|
|
rates = *temp_rates;
|
|
if (rates.oil > 0)
|
|
break;
|
|
}
|
|
// TODO: what about group limits?
|
|
return {getLimitedRatesFromRates_(rates), alq};
|
|
}
|
|
|
|
std::pair<GasLiftSingleWellGeneric::LimitedRates, double>
|
|
GasLiftSingleWellGeneric::increaseALQtoMinALQ_(const double orig_alq, const LimitedRates& orig_rates) const
|
|
{
|
|
auto min_alq = this->min_alq_;
|
|
assert(min_alq >= 0);
|
|
assert(orig_alq < min_alq);
|
|
assert(min_alq < this->max_alq_);
|
|
bool stop_iteration = false;
|
|
double alq = orig_alq;
|
|
LimitedRates rates = orig_rates;
|
|
while (!stop_iteration) {
|
|
double temp_alq = alq + this->increment_;
|
|
|
|
alq = temp_alq;
|
|
if (temp_alq >= min_alq)
|
|
break;
|
|
|
|
auto temp_rates = computeLimitedWellRatesWithALQ_(temp_alq);
|
|
|
|
if (temp_rates) {
|
|
rates = *temp_rates;
|
|
if (rates.limited())
|
|
break;
|
|
}
|
|
}
|
|
return std::make_pair(rates, alq);
|
|
}
|
|
|
|
void
|
|
GasLiftSingleWellGeneric::logSuccess_(double alq, const int iteration_idx)
|
|
{
|
|
const std::string message = fmt::format("GLIFT, IT={}, WELL {} : {} ALQ from {} to {}",
|
|
iteration_idx,
|
|
this->well_name_,
|
|
((alq > this->orig_alq_) ? "increased" : "decreased"),
|
|
this->orig_alq_,
|
|
alq);
|
|
this->deferred_logger_.info(message);
|
|
}
|
|
|
|
std::pair<GasLiftSingleWellGeneric::LimitedRates, double>
|
|
GasLiftSingleWellGeneric::maybeAdjustALQbeforeOptimizeLoop_(const LimitedRates& orig_rates,
|
|
const double orig_alq,
|
|
const bool increase) const
|
|
{
|
|
double alq = orig_alq;
|
|
LimitedRates rates = orig_rates;
|
|
|
|
if (this->debug) {
|
|
const std::string msg = fmt::format("initial ALQ: {}", alq);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
if (!increase) {
|
|
// NOTE: Try to decrease ALQ down to a value where the groups
|
|
// maximum alq target and the total gas + alq target is not violated
|
|
std::tie(rates, alq) = reduceALQtoGroupAlqLimits_(alq, orig_rates);
|
|
if (orig_rates.limited()) {
|
|
// NOTE: Try to decrease ALQ down to a value where the well target is
|
|
// not exceeded.
|
|
// NOTE: This may reduce ALQ below the minimum value set in WLIFTOPT
|
|
// item 5. However, this is OK since the rate target is met and there
|
|
// is no point in using a higher ALQ value then.
|
|
auto [rates1, alq1] = reduceALQtoWellTarget_(alq, orig_rates);
|
|
auto [rates2, alq2] = reduceALQtoGroupTarget(alq, orig_rates);
|
|
if (alq1 < alq2) {
|
|
alq = alq1;
|
|
rates = rates1;
|
|
} else {
|
|
alq = alq2;
|
|
rates = rates2;
|
|
}
|
|
}
|
|
} else {
|
|
if (orig_rates.oil < 0) {
|
|
// Try to increase ALQ up to a value where oil_rate is positive
|
|
std::tie(rates, alq) = increaseALQtoPositiveOilRate_(alq, rates);
|
|
}
|
|
if ((this->min_alq_ > 0) && (alq < this->min_alq_)) {
|
|
// Try to increase ALQ up to the minimum limit without checking
|
|
// the economic gradient..
|
|
std::tie(rates, alq) = increaseALQtoMinALQ_(alq, rates);
|
|
}
|
|
}
|
|
if (orig_alq != alq) {
|
|
if (this->debug) {
|
|
const std::string msg = fmt::format("adjusted ALQ to: {}", alq);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
double delta_alq = alq - orig_alq;
|
|
updateGroupRates_(orig_rates, rates, delta_alq);
|
|
}
|
|
return {rates, alq};
|
|
}
|
|
|
|
bool
|
|
has_control(int controls, Group::InjectionCMode cmode)
|
|
{
|
|
return ((controls & static_cast<int>(cmode)) != 0);
|
|
}
|
|
|
|
// Reduce ALQ to the lowest value greater than zero that still makes at
|
|
// least one rate limited w.r.t. group targets, or reduce ALQ to zero if
|
|
// such positive ALQ value cannot be found.
|
|
std::pair<GasLiftSingleWellGeneric::LimitedRates, double>
|
|
GasLiftSingleWellGeneric::reduceALQtoGroupAlqLimits_(const double orig_alq, const LimitedRates& orig_rates) const
|
|
{
|
|
bool stop_this_iteration = false;
|
|
double alq = orig_alq;
|
|
BasicRates rates {orig_rates};
|
|
double temp_alq = orig_alq;
|
|
while (!stop_this_iteration) {
|
|
if (temp_alq == 0)
|
|
break;
|
|
temp_alq -= this->increment_;
|
|
if (temp_alq < 0)
|
|
temp_alq = 0;
|
|
auto new_rates = computeWellRatesWithALQ_(temp_alq);
|
|
if (!new_rates)
|
|
break;
|
|
auto delta_alq = temp_alq - orig_alq;
|
|
auto delta_gas_rate = new_rates->gas - orig_rates.gas;
|
|
if (!checkGroupTotalRateExceeded(delta_alq, delta_gas_rate)) {
|
|
break;
|
|
}
|
|
rates = *new_rates;
|
|
alq = temp_alq;
|
|
}
|
|
if (alq == orig_alq) {
|
|
return {orig_rates, orig_alq};
|
|
} else {
|
|
LimitedRates limited_rates = getLimitedRatesFromRates_(rates);
|
|
return {limited_rates, alq};
|
|
}
|
|
}
|
|
// Reduce ALQ to the lowest value greater than zero that still makes at
|
|
// least one rate limited w.r.t. group targets, or reduce ALQ to zero if
|
|
// such positive ALQ value cannot be found.
|
|
std::pair<GasLiftSingleWellGeneric::LimitedRates, double>
|
|
GasLiftSingleWellGeneric::reduceALQtoGroupTarget(const double orig_alq, const LimitedRates& orig_rates) const
|
|
{
|
|
bool stop_this_iteration = true;
|
|
const std::vector<std::pair<std::string, double>>& pairs = this->group_info_.getWellGroups(this->well_name_);
|
|
for (const auto& pair /*<group_name, efficiency>*/ : pairs) {
|
|
const auto& group_name = pair.first;
|
|
if (!this->group_state_.has_production_control(group_name))
|
|
continue;
|
|
if (this->group_info_.hasAnyTarget(group_name)) {
|
|
stop_this_iteration = false;
|
|
displayDebugMessage_("Reducing ALQ to meet group target(s) before iteration starts.");
|
|
break;
|
|
}
|
|
}
|
|
double alq = orig_alq;
|
|
BasicRates rates {orig_rates};
|
|
double temp_alq = orig_alq;
|
|
while (!stop_this_iteration) {
|
|
if (temp_alq == 0)
|
|
break;
|
|
temp_alq -= this->increment_;
|
|
if (temp_alq < 0)
|
|
temp_alq = 0;
|
|
auto new_rates = computeWellRatesWithALQ_(temp_alq);
|
|
if (!new_rates)
|
|
break;
|
|
if (!checkGroupTargetsViolated(rates, *new_rates)) {
|
|
break;
|
|
}
|
|
rates = *new_rates;
|
|
alq = temp_alq;
|
|
}
|
|
if (alq == orig_alq) {
|
|
return {orig_rates, orig_alq};
|
|
} else {
|
|
LimitedRates limited_rates = getLimitedRatesFromRates_(rates);
|
|
return {limited_rates, alq};
|
|
}
|
|
}
|
|
|
|
// Reduce ALQ to the lowest value greater than zero that still makes at
|
|
// least one rate limited w.r.t. well targets, or reduce ALQ to zero if
|
|
// such positive ALQ value cannot be found.
|
|
std::pair<GasLiftSingleWellGeneric::LimitedRates, double>
|
|
GasLiftSingleWellGeneric::reduceALQtoWellTarget_(const double orig_alq, const LimitedRates& rates) const
|
|
{
|
|
// this method should only be called if "rates" is limited
|
|
assert(rates.limited());
|
|
if (this->debug) {
|
|
displayDebugMessage_("Reducing ALQ to meet well targets before iteration starts..");
|
|
debugShowLimitingTargets_(rates);
|
|
}
|
|
double alq = orig_alq;
|
|
double temp_alq = alq;
|
|
std::optional<LimitedRates> new_rates;
|
|
bool stop_iteration = false;
|
|
while (!stop_iteration) {
|
|
if (temp_alq == 0)
|
|
break;
|
|
temp_alq -= this->increment_;
|
|
if (temp_alq < 0)
|
|
temp_alq = 0;
|
|
auto temp_rates = computeLimitedWellRatesWithALQ_(temp_alq);
|
|
if (!temp_rates)
|
|
break; // failed to compute BHP given THP limit and ALQ
|
|
// keep iterating until no rate is limited
|
|
if (!temp_rates->limited())
|
|
break;
|
|
alq = temp_alq;
|
|
new_rates = temp_rates;
|
|
}
|
|
assert(alq <= orig_alq);
|
|
if (this->debug) {
|
|
if (alq < orig_alq) {
|
|
// NOTE: ALQ may drop below zero before we are able to meet the target
|
|
const std::string msg = fmt::format("Reduced ALQ from {} to {} to meet rate targets. Rates (new, old) : "
|
|
"oil(({}, {}), gas({}, {}), water({}, {})",
|
|
orig_alq,
|
|
alq,
|
|
new_rates->oil,
|
|
rates.oil,
|
|
new_rates->gas,
|
|
rates.gas,
|
|
new_rates->water,
|
|
rates.water);
|
|
displayDebugMessage_(msg);
|
|
} else if (alq == orig_alq) {
|
|
// We might not be able to reduce ALQ, for example if ALQ starts out at zero.
|
|
const std::string msg = fmt::format("Not able to reduce ALQ {} further. ", orig_alq);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
}
|
|
if (new_rates) {
|
|
return {*new_rates, alq};
|
|
} else {
|
|
return {rates, orig_alq};
|
|
}
|
|
}
|
|
|
|
// INPUT:
|
|
// - increase (boolean) :
|
|
// - true : try increase the lift gas supply,
|
|
// - false : try decrease lift gas supply.
|
|
//
|
|
// OUTPUT:
|
|
//
|
|
// - return value: a new GasLiftWellState or nullptr
|
|
//
|
|
std::unique_ptr<GasLiftWellState>
|
|
GasLiftSingleWellGeneric::runOptimizeLoop_(bool increase)
|
|
{
|
|
if (this->debug)
|
|
debugShowProducerControlMode();
|
|
std::unique_ptr<GasLiftWellState> ret_value; // nullptr initially
|
|
auto [rates, cur_alq] = getInitialRatesWithLimit_();
|
|
if (!rates)
|
|
return ret_value;
|
|
// if (this->debug) debugShowBhpAlqTable_();
|
|
if (this->debug)
|
|
debugShowAlqIncreaseDecreaseCounts_();
|
|
if (this->debug)
|
|
debugShowTargets_();
|
|
bool success = false; // did we succeed to increase alq?
|
|
bool alq_is_limited = false;
|
|
LimitedRates new_rates = *rates;
|
|
auto [temp_rates2, new_alq] = maybeAdjustALQbeforeOptimizeLoop_(*rates, cur_alq, increase);
|
|
if (checkInitialALQmodified_(new_alq, this->orig_alq_)) {
|
|
auto delta_alq = new_alq - cur_alq;
|
|
new_rates = temp_rates2;
|
|
cur_alq = new_alq;
|
|
success = true;
|
|
updateGroupRates_(*rates, new_rates, delta_alq);
|
|
}
|
|
|
|
OptimizeState state {*this, increase};
|
|
auto temp_alq = cur_alq;
|
|
if (checkThpControl_()) {
|
|
if (this->debug)
|
|
debugShowStartIteration_(temp_alq, increase, new_rates.oil);
|
|
} else {
|
|
// If the well is not under THP control, we can still use the previous
|
|
// initial adjustment of ALQ by using the well's THP limit to calculate
|
|
// BHP and then well rates from that.
|
|
// This is useful for example for wells under group control to reduce
|
|
// their gaslift. A typical case for this could be that a new well opens up.
|
|
// Then gaslift can be reduced while still keeping the group target.
|
|
state.stop_iteration = true;
|
|
}
|
|
while (!state.stop_iteration && (++state.it <= this->max_iterations_)) {
|
|
if (state.checkRatesViolated(new_rates))
|
|
break;
|
|
if (state.checkAlqOutsideLimits(temp_alq, new_rates.oil))
|
|
break;
|
|
std::optional<double> alq_opt;
|
|
std::tie(alq_opt, alq_is_limited) = state.addOrSubtractAlqIncrement(temp_alq);
|
|
if (!alq_opt)
|
|
break;
|
|
auto delta_alq = *alq_opt - temp_alq;
|
|
if (checkGroupALQrateExceeded(delta_alq))
|
|
break;
|
|
|
|
temp_alq = *alq_opt;
|
|
if (this->debug)
|
|
state.debugShowIterationInfo(temp_alq);
|
|
rates = new_rates;
|
|
auto temp_rates = computeLimitedWellRatesWithALQ_(temp_alq);
|
|
if (!temp_rates)
|
|
break;
|
|
if (temp_rates->bhp_is_limited)
|
|
state.stop_iteration = true;
|
|
temp_rates = updateRatesToGroupLimits_(*rates, *temp_rates);
|
|
|
|
auto delta_gas_rate = temp_rates->gas - rates->gas;
|
|
if (checkGroupTotalRateExceeded(delta_alq, delta_gas_rate))
|
|
break;
|
|
|
|
/* if (this->debug_abort_if_increase_and_gas_is_limited_) {
|
|
if (gas_is_limited && increase) {
|
|
// if gas is limited we do not want to increase
|
|
displayDebugMessage_(
|
|
"increasing ALQ and gas is limited -> aborting iteration");
|
|
break;
|
|
}
|
|
}
|
|
*/
|
|
auto gradient = state.calcEcoGradient(rates->oil, temp_rates->oil, rates->gas, temp_rates->gas);
|
|
if (this->debug)
|
|
debugCheckNegativeGradient_(
|
|
gradient, cur_alq, temp_alq, rates->oil, temp_rates->oil, rates->gas, temp_rates->gas, increase);
|
|
if (state.checkEcoGradient(gradient))
|
|
break;
|
|
cur_alq = temp_alq;
|
|
success = true;
|
|
new_rates = *temp_rates;
|
|
updateGroupRates_(*rates, new_rates, delta_alq);
|
|
}
|
|
if (state.it > this->max_iterations_) {
|
|
warnMaxIterationsExceeded_();
|
|
}
|
|
std::optional<bool> increase_opt;
|
|
if (success) {
|
|
this->well_state_.gliftUpdateAlqIncreaseCount(this->well_name_, increase);
|
|
increase_opt = increase;
|
|
} else {
|
|
increase_opt = std::nullopt;
|
|
}
|
|
ret_value = std::make_unique<GasLiftWellState>(new_rates.oil,
|
|
new_rates.oil_is_limited,
|
|
new_rates.gas,
|
|
new_rates.gas_is_limited,
|
|
cur_alq,
|
|
alq_is_limited,
|
|
new_rates.water,
|
|
new_rates.water_is_limited,
|
|
increase_opt);
|
|
return ret_value;
|
|
}
|
|
|
|
std::unique_ptr<GasLiftWellState>
|
|
GasLiftSingleWellGeneric::runOptimize1_()
|
|
{
|
|
std::unique_ptr<GasLiftWellState> state;
|
|
int inc_count = this->well_state_.gliftGetAlqIncreaseCount(this->well_name_);
|
|
int dec_count = this->well_state_.gliftGetAlqDecreaseCount(this->well_name_);
|
|
if (dec_count == 0 && inc_count == 0) {
|
|
state = tryIncreaseLiftGas_();
|
|
if (!state || !(state->alqChanged())) {
|
|
state = tryDecreaseLiftGas_();
|
|
}
|
|
} else if (dec_count == 0) {
|
|
assert(inc_count > 0);
|
|
state = tryIncreaseLiftGas_();
|
|
} else if (inc_count == 0) {
|
|
assert(dec_count > 0);
|
|
state = tryDecreaseLiftGas_();
|
|
}
|
|
return state;
|
|
}
|
|
|
|
std::unique_ptr<GasLiftWellState>
|
|
GasLiftSingleWellGeneric::runOptimize2_()
|
|
{
|
|
std::unique_ptr<GasLiftWellState> state;
|
|
state = tryIncreaseLiftGas_();
|
|
if (!state || !(state->alqChanged())) {
|
|
state = tryDecreaseLiftGas_();
|
|
}
|
|
return state;
|
|
}
|
|
|
|
std::unique_ptr<GasLiftWellState>
|
|
GasLiftSingleWellGeneric::tryDecreaseLiftGas_()
|
|
{
|
|
return runOptimizeLoop_(/*increase=*/false);
|
|
}
|
|
|
|
std::unique_ptr<GasLiftWellState>
|
|
GasLiftSingleWellGeneric::tryIncreaseLiftGas_()
|
|
{
|
|
return runOptimizeLoop_(/*increase=*/true);
|
|
}
|
|
|
|
void
|
|
GasLiftSingleWellGeneric::setAlqMinRate_(const GasLiftWell& well)
|
|
{
|
|
// NOTE: According to WLIFTOPT item 5 :
|
|
// if min_rate() is negative, it means: allocate at least enough lift gas
|
|
// to enable the well to flow
|
|
// NOTE: "to enable the well to flow" : How to interpret this?
|
|
// We choose to interpret it to mean a positive oil rate as returned from
|
|
//
|
|
// computeWellRates_(bhp, cur_potentials);
|
|
//
|
|
// So even if the well is producing gas, if the oil rate is zero
|
|
// we say that the "well is not flowing".
|
|
//
|
|
// Note that if WECON item 2 is set, the well can be shut off
|
|
// before the flow rate reaches zero. Also,
|
|
// if bhp drops below the bhp lower limit, the well might switch to bhp
|
|
// control before the oil rate becomes zero.
|
|
|
|
this->min_alq_ = well.min_rate();
|
|
if (this->min_alq_ > 0) {
|
|
if (this->min_alq_ >= this->max_alq_) {
|
|
// NOTE: We reset the value to a negative value.
|
|
// negative value means: Allocate at least enough lift gas
|
|
// to allow the well to flow.
|
|
// TODO: Consider other options for resetting the value..
|
|
this->min_alq_ = -1;
|
|
displayWarning_("Minimum ALQ value is larger than maximum ALQ value!"
|
|
" Resetting value.");
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
GasLiftSingleWellGeneric::updateGroupRates_(const LimitedRates& rates,
|
|
const LimitedRates& new_rates,
|
|
double delta_alq) const
|
|
{
|
|
double delta_oil = new_rates.oil - rates.oil;
|
|
double delta_gas = new_rates.gas - rates.gas;
|
|
double delta_water = new_rates.water - rates.water;
|
|
const auto& pairs = this->group_info_.getWellGroups(this->well_name_);
|
|
for (const auto& [group_name, efficiency] : pairs) {
|
|
int idx = this->group_info_.getGroupIdx(group_name);
|
|
// This will notify the optimize loop in BlackoilWellModel, see
|
|
// gasLiftOptimizationStage1() in BlackoilWellModel_impl.hpp
|
|
// that this group_info needs to be synchronized to the other MPI ranks
|
|
this->sync_groups_.insert(idx);
|
|
this->group_info_.update(group_name,
|
|
efficiency * delta_oil,
|
|
efficiency * delta_gas,
|
|
efficiency * delta_water,
|
|
efficiency * delta_alq);
|
|
}
|
|
}
|
|
|
|
GasLiftSingleWellGeneric::LimitedRates
|
|
GasLiftSingleWellGeneric::updateRatesToGroupLimits_(const BasicRates& old_rates, const LimitedRates& rates, const std::string& gr_name) const
|
|
{
|
|
LimitedRates new_rates = rates;
|
|
auto [new_oil_rate, oil_is_limited] = getOilRateWithGroupLimit_(new_rates.oil, old_rates.oil, gr_name);
|
|
if (oil_is_limited) {
|
|
new_rates.oil_limiting_target = Rate::oil;
|
|
}
|
|
auto [new_gas_rate, gas_is_limited] = getGasRateWithGroupLimit_(new_rates.gas, old_rates.gas, gr_name);
|
|
auto [new_water_rate, water_is_limited] = getWaterRateWithGroupLimit_(new_rates.water, old_rates.water, gr_name);
|
|
if (water_is_limited) {
|
|
new_rates.water_limiting_target = Rate::water;
|
|
}
|
|
auto [new_oil_rate2, new_water_rate2, oil_is_limited2, water_is_limited2]
|
|
= getLiquidRateWithGroupLimit_(new_oil_rate, old_rates.oil, new_water_rate, old_rates.water, gr_name);
|
|
if (oil_is_limited2) {
|
|
new_rates.oil_limiting_target = Rate::liquid;
|
|
}
|
|
if (water_is_limited2) {
|
|
new_rates.water_limiting_target = Rate::liquid;
|
|
}
|
|
new_rates.oil = new_oil_rate2;
|
|
new_rates.gas = new_gas_rate;
|
|
new_rates.water = new_water_rate2;
|
|
new_rates.oil_is_limited = rates.oil_is_limited || oil_is_limited || oil_is_limited2;
|
|
new_rates.gas_is_limited = rates.gas_is_limited || gas_is_limited;
|
|
new_rates.water_is_limited = rates.water_is_limited || water_is_limited || water_is_limited2;
|
|
if (oil_is_limited || oil_is_limited2 || gas_is_limited || water_is_limited || water_is_limited2) {
|
|
new_rates.limit_type = LimitedRates::LimitType::group;
|
|
}
|
|
return new_rates;
|
|
}
|
|
|
|
// Called when we should use a fixed ALQ value
|
|
void
|
|
GasLiftSingleWellGeneric::updateWellStateAlqFixedValue_(const GasLiftWell& well)
|
|
{
|
|
auto& max_alq_optional = well.max_rate();
|
|
if (max_alq_optional) {
|
|
// According to WLIFTOPT, item 3:
|
|
// If item 2 is NO, then item 3 is regarded as the fixed
|
|
// lift gas injection rate for the well.
|
|
auto new_alq = *max_alq_optional;
|
|
this->well_state_.setALQ(this->well_name_, new_alq);
|
|
}
|
|
// else {
|
|
// // If item 3 is defaulted, the lift gas rate remains
|
|
// // unchanged at its current value.
|
|
//}
|
|
}
|
|
|
|
// Determine if we should use a fixed ALQ value.
|
|
//
|
|
// From the manual for WLIFTOPT, item 2:
|
|
// Is the well's lift gas injection rate to be calculated by the
|
|
// optimization facility?
|
|
// - YES : The well's lift gas injection rate is calculated by the
|
|
// optimization facility.
|
|
// - NO : The well's lift gas injection rate remains fixed at a
|
|
// value that can be set either in Item 3 of this keyword, or in
|
|
// Item 12 of keyword WCONPROD, or with keyword WELTARG.
|
|
bool
|
|
GasLiftSingleWellGeneric::useFixedAlq_(const GasLiftWell& well)
|
|
{
|
|
auto wliftopt_item2 = well.use_glo();
|
|
if (wliftopt_item2) {
|
|
return false;
|
|
} else {
|
|
displayDebugMessage_("WLIFTOPT item2 = NO. Skipping optimization.");
|
|
// auto& max_alq_optional = well.max_rate();
|
|
// if (max_alq_optional) {
|
|
// According to WLIFTOPT, item 3:
|
|
// If item 2 is NO, then item 3 is regarded as the fixed
|
|
// lift gas injection rate for the well.
|
|
// }
|
|
// else {
|
|
// If item 3 is defaulted, the lift gas rate remains
|
|
// unchanged at its current value.
|
|
// }
|
|
return true;
|
|
}
|
|
}
|
|
|
|
void
|
|
GasLiftSingleWellGeneric::debugInfoGroupRatesExceedTarget(Rate rate_type,
|
|
const std::string& gr_name,
|
|
double rate,
|
|
double target) const
|
|
{
|
|
const std::string msg = fmt::format("{} rate for group {} exceeds target: "
|
|
"rate = {}, target = {}, the old rate is kept.",
|
|
GasLiftGroupInfo::rateToString(rate_type),
|
|
gr_name,
|
|
rate,
|
|
target);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
|
|
void
|
|
GasLiftSingleWellGeneric::warnMaxIterationsExceeded_()
|
|
{
|
|
const std::string msg = fmt::format("Max iterations ({}) exceeded", this->max_iterations_);
|
|
displayWarning_(msg);
|
|
}
|
|
|
|
/****************************************
|
|
* Methods declared in OptimizeState
|
|
****************************************/
|
|
|
|
std::pair<std::optional<double>, bool>
|
|
GasLiftSingleWellGeneric::OptimizeState::addOrSubtractAlqIncrement(double alq)
|
|
{
|
|
auto [alq_opt, limited] = this->parent.addOrSubtractAlqIncrement_(alq, this->increase);
|
|
if (!alq_opt) {
|
|
const std::string msg = fmt::format("iteration {}, alq = {} : not able to {} ALQ increment",
|
|
this->it,
|
|
alq,
|
|
(this->increase ? "add" : "subtract"));
|
|
}
|
|
return {alq_opt, limited};
|
|
}
|
|
|
|
double
|
|
GasLiftSingleWellGeneric::OptimizeState::calcEcoGradient(double oil_rate,
|
|
double new_oil_rate,
|
|
double gas_rate,
|
|
double new_gas_rate)
|
|
{
|
|
return this->parent.calcEcoGradient_(oil_rate, new_oil_rate, gas_rate, new_gas_rate, this->increase);
|
|
}
|
|
|
|
// NOTE: According to WLIFTOPT item 5 :
|
|
// if min_rate() is negative, it means: allocate at least enough lift gas
|
|
// to enable the well to flow
|
|
// We will interpret this as (see discussion above GasLiftSingleWell()
|
|
// in this file): Allocate at least the amount of lift gas needed to
|
|
// get a positive oil production rate.
|
|
bool
|
|
GasLiftSingleWellGeneric::OptimizeState::checkAlqOutsideLimits(double alq, [[maybe_unused]] double oil_rate)
|
|
{
|
|
std::ostringstream ss;
|
|
bool result = false;
|
|
|
|
if (this->increase) {
|
|
if (alq >= this->parent.max_alq_) {
|
|
ss << "ALQ >= " << this->parent.max_alq_ << " (max limit), "
|
|
<< "stopping iteration";
|
|
result = true;
|
|
} else { // checking the minimum limit...
|
|
// NOTE: A negative min_alq_ means: allocate at least enough lift gas
|
|
// to enable the well to flow, see WLIFTOPT item 5.
|
|
if (this->parent.min_alq_ < 0) {
|
|
// - if oil rate is negative (i.e. the well is not flowing), continue to
|
|
// increase ALQ (according WLIFTOPT item 5) and try make the well
|
|
// flow.
|
|
// - else if oil rate is already positive, there is no minimum
|
|
// limit for ALQ in this case
|
|
result = false;
|
|
} else {
|
|
// NOTE: checking for a lower limit is not necessary
|
|
// when increasing alq. If ALQ was smaller than the minimum when
|
|
// we entered the runOptimizeLoop_() method,
|
|
// increaseALQtoMinALQ_() will ensure that ALQ >= min_alq
|
|
assert(alq >= this->parent.min_alq_);
|
|
result = false;
|
|
}
|
|
}
|
|
} else { // we are decreasing lift gas
|
|
if (alq == 0) {
|
|
ss << "ALQ is zero, cannot decrease further. Stopping iteration. ";
|
|
result = true;
|
|
} else if (alq < 0) {
|
|
ss << "Negative ALQ: " << alq << ". Stopping iteration. ";
|
|
result = true;
|
|
}
|
|
// NOTE: A negative min_alq_ means: allocate at least enough lift gas
|
|
// to enable the well to flow, see WLIFTOPT item 5.
|
|
if (this->parent.min_alq_ < 0) {
|
|
// We know that the well is flowing (oil_rate > 0) since that was
|
|
// already checked in runOptimizeLoop_() by calling checkNegativeOilRate()
|
|
assert(oil_rate >= 0);
|
|
result = false;
|
|
} else {
|
|
if (alq <= this->parent.min_alq_) {
|
|
// According to WLIFTOPT item 5:
|
|
// "If a positive value is specified, the well is
|
|
// allocated at least that amount of lift gas,
|
|
// unless the well is unable to flow with that rate
|
|
// of lift gas injection, or unless the well can
|
|
// already meet one of its own rate limits before
|
|
// receiving its minimum lift gas rate."
|
|
//
|
|
// - We already know that the well is flowing, (oil_rate > 0),
|
|
// since that was already checked in runOptimizeLoop_() by calling
|
|
// checkRatesViolated().
|
|
// - We also know that the rate limit was not exceeded since that was
|
|
// checked by checkRatesViolated()
|
|
assert(oil_rate >= 0);
|
|
ss << "ALQ <= " << this->parent.min_alq_ << " (min limit), "
|
|
<< "stopping iteration";
|
|
result = true;
|
|
} else {
|
|
// NOTE: checking for an upper limit should not be necessary
|
|
// when decreasing alq.. so this is just to catch an
|
|
// illegal state at an early point.
|
|
if (this->parent.checkALQequal_(alq, this->parent.max_alq_)) {
|
|
return false;
|
|
} else if (alq > this->parent.max_alq_) {
|
|
warn_("unexpected: alq above upper limit when trying to "
|
|
"decrease lift gas. aborting iteration.");
|
|
result = true;
|
|
} else {
|
|
result = false;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (this->parent.debug) {
|
|
const std::string msg = ss.str();
|
|
if (!msg.empty())
|
|
this->parent.displayDebugMessage_(msg);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
bool
|
|
GasLiftSingleWellGeneric::checkGroupALQrateExceeded(double delta_alq, const std::string& gr_name_dont_limit) const
|
|
{
|
|
const auto& pairs = group_info_.getWellGroups(well_name_);
|
|
for (const auto& [group_name, efficiency] : pairs) {
|
|
// in stage 2 we don't want to limit the rate to the group
|
|
// target we are trying to redistribute the gaslift within
|
|
if (gr_name_dont_limit == group_name)
|
|
continue;
|
|
auto max_alq_opt = group_info_.maxAlq(group_name);
|
|
if (max_alq_opt) {
|
|
double alq = group_info_.alqRate(group_name) + efficiency * delta_alq;
|
|
if (alq > *max_alq_opt) {
|
|
if (debug) {
|
|
const std::string msg = fmt::format(
|
|
"Group {} : alq {} exceeds max_alq {}. Stopping iteration", group_name, alq, *max_alq_opt);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool
|
|
GasLiftSingleWellGeneric::checkGroupTotalRateExceeded(double delta_alq, double delta_gas_rate) const
|
|
{
|
|
const auto& pairs = group_info_.getWellGroups(well_name_);
|
|
for (const auto& [group_name, efficiency] : pairs) {
|
|
auto max_total_rate_opt = group_info_.maxTotalGasRate(group_name);
|
|
if (max_total_rate_opt) {
|
|
double alq = group_info_.alqRate(group_name) + efficiency * delta_alq;
|
|
double gas_rate = group_info_.gasRate(group_name) + efficiency * delta_gas_rate;
|
|
|
|
if ((alq + gas_rate) > *max_total_rate_opt) {
|
|
if (debug) {
|
|
const std::string msg
|
|
= fmt::format("Group {} : total gas rate {} exceeds max_total_gas_rate {}. Stopping iteration",
|
|
group_name,
|
|
alq + gas_rate,
|
|
*max_total_rate_opt);
|
|
displayDebugMessage_(msg);
|
|
}
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
//
|
|
// bool checkEcoGradient(double gradient)
|
|
//
|
|
// - Determine if the gradient has reached the limit of the economic gradient.
|
|
//
|
|
// - If we are increasing lift gas, returns true if the gradient is smaller
|
|
// than or equal to the economic gradient,
|
|
//
|
|
// - If we are decreasing lift gas, returns true if the gradient is greater
|
|
// than or equal to the economic gradient. (I.e., we assume too much lift gas
|
|
// is being used and the gradient has become too small. We try to decrease
|
|
// lift gas until the gradient increases and reaches the economic gradient..)
|
|
//
|
|
bool
|
|
GasLiftSingleWellGeneric::OptimizeState::checkEcoGradient(double gradient)
|
|
{
|
|
std::ostringstream ss;
|
|
bool result = false;
|
|
|
|
if (this->parent.debug) {
|
|
ss << "checking gradient: " << gradient;
|
|
}
|
|
if (this->increase) {
|
|
if (this->parent.debug)
|
|
ss << " <= " << this->parent.eco_grad_ << " --> ";
|
|
if (gradient <= this->parent.eco_grad_) {
|
|
if (this->parent.debug)
|
|
ss << "yes, stopping";
|
|
result = true;
|
|
} else {
|
|
if (this->parent.debug)
|
|
ss << "no, continue";
|
|
}
|
|
} else { // decreasing lift gas
|
|
if (this->parent.debug)
|
|
ss << " >= " << this->parent.eco_grad_ << " --> ";
|
|
if (gradient >= this->parent.eco_grad_) {
|
|
if (this->parent.debug)
|
|
ss << "yes, stopping";
|
|
result = true;
|
|
} else {
|
|
if (this->parent.debug)
|
|
ss << "no, continue";
|
|
}
|
|
}
|
|
if (this->parent.debug)
|
|
this->parent.displayDebugMessage_(ss.str());
|
|
return result;
|
|
}
|
|
|
|
bool
|
|
GasLiftSingleWellGeneric::OptimizeState::checkRatesViolated(const LimitedRates& rates) const
|
|
{
|
|
if (!this->increase) {
|
|
if (rates.oil < 0) {
|
|
// The well is not flowing, and it will(?) not help to reduce lift
|
|
// gas further. Note that this assumes that the oil rates drops with
|
|
// decreasing lift gas.
|
|
this->parent.displayDebugMessage_("Negative oil rate detected while descreasing "
|
|
"lift gas. Stopping iteration.");
|
|
return true;
|
|
}
|
|
}
|
|
if (rates.limited()) {
|
|
if (this->parent.debug) {
|
|
const std::string well_or_group = rates.limit_type == LimitedRates::LimitType::well ? "well" : "group";
|
|
std::string target_type;
|
|
std::string rate_type;
|
|
if (rates.oil_is_limited) {
|
|
target_type = GasLiftGroupInfo::rateToString(*(rates.oil_limiting_target));
|
|
rate_type = "oil";
|
|
} else if (rates.gas_is_limited) {
|
|
target_type = "gas";
|
|
rate_type = "gas";
|
|
} else if (rates.water_is_limited) {
|
|
target_type = GasLiftGroupInfo::rateToString(*(rates.water_limiting_target));
|
|
rate_type = "water";
|
|
}
|
|
const std::string msg = fmt::format("iteration {} : {} rate was limited due to {} {} target. "
|
|
"Stopping iteration",
|
|
this->it,
|
|
rate_type,
|
|
well_or_group,
|
|
target_type);
|
|
this->parent.displayDebugMessage_(msg);
|
|
}
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void
|
|
GasLiftSingleWellGeneric::OptimizeState::debugShowIterationInfo(double alq)
|
|
{
|
|
const std::string msg = fmt::format("iteration {}, ALQ = {}", this->it, alq);
|
|
this->parent.displayDebugMessage_(msg);
|
|
}
|
|
|
|
|
|
// NOTE: When calculating the gradient, determine what the well would produce if
|
|
// the lift gas injection rate were increased by one increment. The
|
|
// production rates are adjusted if necessary to obey
|
|
// any rate or BHP limits that the well may be subject to. From this
|
|
// information, calculate the well's "weighted incremental
|
|
// gradient"
|
|
//
|
|
// TODO: What does it mean to "adjust the production rates" given a
|
|
// BHP limit?
|
|
//
|
|
double
|
|
GasLiftSingleWellGeneric::OptimizeState::getBhpWithLimit()
|
|
{
|
|
auto [new_bhp, limited] = this->parent.getBhpWithLimit_(this->bhp);
|
|
if (limited) {
|
|
// TODO: is it possible that bhp falls below the limit when
|
|
// adding lift gas? I.e. if this->increase == true..
|
|
// TODO: we keep the current alq, but it should probably
|
|
// be adjusted since we changed computed bhp. But how?
|
|
|
|
// Stop iteration, but first check the economic gradient
|
|
// with the bhp_update. If the gradient looks OK (see the
|
|
// main optimize loop) we keep the current ALQ value.
|
|
this->stop_iteration = true;
|
|
}
|
|
return new_bhp;
|
|
}
|
|
|
|
/****************************************
|
|
* Methods declared in BasicRates
|
|
****************************************/
|
|
|
|
GasLiftSingleWellGeneric::BasicRates::BasicRates(const LimitedRates& rates)
|
|
{
|
|
oil = rates.oil;
|
|
gas = rates.gas;
|
|
water = rates.water;
|
|
bhp_is_limited = rates.bhp_is_limited;
|
|
}
|
|
|
|
|
|
} // namespace Opm
|