From 24b23933347c38e59c284a233100af8c2184e2ef Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Atgeirr=20Fl=C3=B8=20Rasmussen?= <atgeirr@sintef.no>
Date: Thu, 15 Oct 2020 17:56:11 +0200
Subject: [PATCH] Add parameter --alternative-well-rate-init.

With this, a slightly more sophisticated procedure is used for well rate intialization.
Since it changes existing results, it defaults to false, giving the existing behaviour.
---
 opm/simulators/flow/BlackoilModelParametersEbos.hpp |  9 +++++++++
 opm/simulators/wells/BlackoilWellModel.hpp          |  1 +
 opm/simulators/wells/BlackoilWellModel_impl.hpp     | 10 +++++++---
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/opm/simulators/flow/BlackoilModelParametersEbos.hpp b/opm/simulators/flow/BlackoilModelParametersEbos.hpp
index f776617b4..27d304cd6 100644
--- a/opm/simulators/flow/BlackoilModelParametersEbos.hpp
+++ b/opm/simulators/flow/BlackoilModelParametersEbos.hpp
@@ -145,6 +145,10 @@ template<class TypeTag, class MyTypeTag>
 struct MaxInnerIterWells {
     using type = UndefinedProperty;
 };
+template<class TypeTag, class MyTypeTag>
+struct AlternativeWellRateInit {
+    using type = UndefinedProperty;
+};
 
 template<class TypeTag>
 struct DbhpMaxRel<TypeTag, TTag::FlowModelParameters> {
@@ -251,6 +255,10 @@ struct MaxInnerIterWells<TypeTag, TTag::FlowModelParameters> {
     static constexpr int value = 50;
 };
 template<class TypeTag>
+struct AlternativeWellRateInit<TypeTag, TTag::FlowModelParameters> {
+    static constexpr bool value = false;
+};
+template<class TypeTag>
 struct StrictInnerIterMsWells<TypeTag, TTag::FlowModelParameters> {
     static constexpr int value = 40;
 };
@@ -432,6 +440,7 @@ namespace Opm
             EWOMS_REGISTER_PARAM(TypeTag, int, StrictInnerIterMsWells, "Number of inner iterations for multi-segment wells with strict tolerance");
             EWOMS_REGISTER_PARAM(TypeTag, bool, UseInnerIterationsWells, "Use nested iterations for standard wells");
             EWOMS_REGISTER_PARAM(TypeTag, int, MaxInnerIterWells, "Maximum number of inner iterations for standard wells");
+            EWOMS_REGISTER_PARAM(TypeTag, bool, AlternativeWellRateInit, "Use alternative well rate initialization procedure");
             EWOMS_REGISTER_PARAM(TypeTag, Scalar, RegularizationFactorMsw, "Regularization factor for ms wells");
             EWOMS_REGISTER_PARAM(TypeTag, Scalar, MaxSinglePrecisionDays, "Maximum time step size where single precision floating point arithmetic can be used solving for the linear systems of equations");
             EWOMS_REGISTER_PARAM(TypeTag, int, MaxStrictIter, "Maximum number of Newton iterations before relaxed tolerances are used for the CNV convergence criterion");
diff --git a/opm/simulators/wells/BlackoilWellModel.hpp b/opm/simulators/wells/BlackoilWellModel.hpp
index 41817eadf..e638e1002 100644
--- a/opm/simulators/wells/BlackoilWellModel.hpp
+++ b/opm/simulators/wells/BlackoilWellModel.hpp
@@ -307,6 +307,7 @@ namespace Opm {
             bool initial_step_;
             bool report_step_starts_;
             bool glift_debug = false;
+            bool alternative_well_rate_init_;
             std::unique_ptr<RateConverterType> rateConverter_;
             std::unique_ptr<VFPProperties<VFPInjProperties,VFPProdProperties>> vfp_properties_;
 
diff --git a/opm/simulators/wells/BlackoilWellModel_impl.hpp b/opm/simulators/wells/BlackoilWellModel_impl.hpp
index 6fb269399..3be53596b 100644
--- a/opm/simulators/wells/BlackoilWellModel_impl.hpp
+++ b/opm/simulators/wells/BlackoilWellModel_impl.hpp
@@ -63,6 +63,8 @@ namespace Opm {
                                                  value);
                 return candidate == parallel_wells.end() || *candidate != value;
             };
+
+        alternative_well_rate_init_ = EWOMS_GET_PARAM(TypeTag, bool, AlternativeWellRateInit);
     }
 
     template<typename TypeTag>
@@ -393,9 +395,11 @@ namespace Opm {
             local_deferredLogger.warning("WELL_POTENTIAL_CALCULATION_FAILED", msg);
         }
 
-        // Update the well rates to match state, if only single-phase rates.
-        for (auto& well : well_container_) {
-            well->updateWellStateRates(ebosSimulator_, well_state_, local_deferredLogger);
+        if (alternative_well_rate_init_) {
+            // Update the well rates to match state, if only single-phase rates.
+            for (auto& well : well_container_) {
+                well->updateWellStateRates(ebosSimulator_, well_state_, local_deferredLogger);
+            }
         }
 
         //compute well guideRates