From faea69fdb26464b1570e849119d76f6b1f6205ac Mon Sep 17 00:00:00 2001
From: Antonella Ritorto <anto.ritorto@gmail.com>
Date: Fri, 2 May 2025 14:06:21 +0200
Subject: [PATCH 1/2] Update cell depth and thickness in serial simulation for
 CpGrid with LGRs

---
 opm/models/utils/simulator.hh            | 24 +++++++++++++-----------
 opm/simulators/flow/CpGridVanguard.hpp   |  4 ++++
 opm/simulators/flow/FlowBaseVanguard.hpp |  6 +++---
 3 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/opm/models/utils/simulator.hh b/opm/models/utils/simulator.hh
index 1975500c12..12dc7b63e5 100644
--- a/opm/models/utils/simulator.hh
+++ b/opm/models/utils/simulator.hh
@@ -129,17 +129,6 @@ public:
             OPM_END_PARALLEL_TRY_CATCH("Allocating the simulation vanguard failed: ", comm);
         }
 
-        // Only relevant for CpGrid
-        if (verbose_) {
-            std::cout << "Adding LGRs, if any\n" << std::flush;
-        }
-
-        {
-            OPM_BEGIN_PARALLEL_TRY_CATCH();
-            vanguard_->addLgrs();
-            OPM_END_PARALLEL_TRY_CATCH("Adding LGRs to the simulation vanguard failed: ", comm);
-        }
-
         if (verbose_) {
             std::cout << "Distributing the vanguard's data\n" << std::flush;
         }
@@ -150,6 +139,19 @@ public:
             OPM_END_PARALLEL_TRY_CATCH("Could not distribute the vanguard data: ", comm);
         }
 
+        // Only relevant for CpGrid
+        if (verbose_) {
+            std::cout << "Adding LGRs, if any, in serial run\n" << std::flush;
+        }
+
+        {
+            if ( comm.size() == 1 ) { // serial run
+                OPM_BEGIN_PARALLEL_TRY_CATCH();
+                vanguard_->addLgrs();
+                OPM_END_PARALLEL_TRY_CATCH("Adding LGRs to the simulation vanguard in serial run failed: ", comm);
+            }
+        }
+
         if (verbose_) {
             std::cout << "Allocating the model\n" << std::flush;
         }
diff --git a/opm/simulators/flow/CpGridVanguard.hpp b/opm/simulators/flow/CpGridVanguard.hpp
index 22beeaca18..8769e7b9b1 100644
--- a/opm/simulators/flow/CpGridVanguard.hpp
+++ b/opm/simulators/flow/CpGridVanguard.hpp
@@ -258,6 +258,10 @@ public:
         if (const auto& lgrs = this->eclState().getLgrs(); lgrs.size() > 0) {
             OpmLog::info("\nAdding LGRs to the grid and updating its leaf grid view");
             this->addLgrsUpdateLeafView(lgrs, lgrs.size(), *this->grid_);
+
+            this->updateGridView_();
+            this->updateCellDepths_();
+            this->updateCellThickness_();
         }
     }
 
diff --git a/opm/simulators/flow/FlowBaseVanguard.hpp b/opm/simulators/flow/FlowBaseVanguard.hpp
index 2339e19442..7951f2f184 100644
--- a/opm/simulators/flow/FlowBaseVanguard.hpp
+++ b/opm/simulators/flow/FlowBaseVanguard.hpp
@@ -362,9 +362,9 @@ protected:
             cellCenterDepth_[elemIdx] = cellCenterDepth(element);
 
             if (!num_aqu_cells.empty()) {
-               const unsigned int global_index = cartesianIndex(elemIdx);
-               const auto search = num_aqu_cells.find(global_index);
-               if (search != num_aqu_cells.end()) {
+                const unsigned int global_index = cartesianIndex(elemIdx);
+                const auto search = num_aqu_cells.find(global_index);
+                if (search != num_aqu_cells.end()) {
                     // updating the cell depth using aquifer cell depth
                     cellCenterDepth_[elemIdx] = search->second->depth;
                 }

From bdfafbd5cdc15307eee790f3e6a765d68929a365 Mon Sep 17 00:00:00 2001
From: Antonella Ritorto <anto.ritorto@gmail.com>
Date: Wed, 7 May 2025 16:50:31 +0200
Subject: [PATCH 2/2] Move the if-serial run into CpGridVanguard::addLgrs(),
 warn if parallel

---
 opm/models/utils/simulator.hh          | 10 ++++------
 opm/simulators/flow/CpGridVanguard.hpp |  5 ++++-
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/opm/models/utils/simulator.hh b/opm/models/utils/simulator.hh
index 12dc7b63e5..c6353c5f51 100644
--- a/opm/models/utils/simulator.hh
+++ b/opm/models/utils/simulator.hh
@@ -139,17 +139,15 @@ public:
             OPM_END_PARALLEL_TRY_CATCH("Could not distribute the vanguard data: ", comm);
         }
 
-        // Only relevant for CpGrid
+        // Only relevant for CpGrid and serial runs.
         if (verbose_) {
             std::cout << "Adding LGRs, if any, in serial run\n" << std::flush;
         }
 
         {
-            if ( comm.size() == 1 ) { // serial run
-                OPM_BEGIN_PARALLEL_TRY_CATCH();
-                vanguard_->addLgrs();
-                OPM_END_PARALLEL_TRY_CATCH("Adding LGRs to the simulation vanguard in serial run failed: ", comm);
-            }
+            OPM_BEGIN_PARALLEL_TRY_CATCH();
+            vanguard_->addLgrs();
+            OPM_END_PARALLEL_TRY_CATCH("Adding LGRs to the simulation vanguard in serial run failed: ", comm);
         }
 
         if (verbose_) {
diff --git a/opm/simulators/flow/CpGridVanguard.hpp b/opm/simulators/flow/CpGridVanguard.hpp
index 8769e7b9b1..daf0e7d118 100644
--- a/opm/simulators/flow/CpGridVanguard.hpp
+++ b/opm/simulators/flow/CpGridVanguard.hpp
@@ -255,7 +255,7 @@ public:
         // Check if input file contains Lgrs.
         //
         // If there are lgrs, create the grid with them, and update the leaf grid view.
-        if (const auto& lgrs = this->eclState().getLgrs(); lgrs.size() > 0) {
+        if (const auto& lgrs = this->eclState().getLgrs(); (lgrs.size() > 0) && (this->grid_->comm().size() == 1)) {
             OpmLog::info("\nAdding LGRs to the grid and updating its leaf grid view");
             this->addLgrsUpdateLeafView(lgrs, lgrs.size(), *this->grid_);
 
@@ -263,6 +263,9 @@ public:
             this->updateCellDepths_();
             this->updateCellThickness_();
         }
+        else {
+            Opm::OpmLog::warning("Adding LGRs in parallel run is not supported yet.\n");
+        }
     }
 
     unsigned int gridEquilIdxToGridIdx(unsigned int elemIndex) const {