From a8b83fce8555e42fd720f97160ed3f2c626c866e Mon Sep 17 00:00:00 2001
From: xiao312 <xiaoxiao1642@163.com>
Date: Tue, 24 Jun 2025 10:49:54 +0800
Subject: [PATCH 1/2] Calling syncState() on Cantera Reactor in
 dfChemistryModel to avoid repetitive initialization.

---
 src/dfChemistryModel/dfChemistryModel.C | 27 ++++++++++++++++---------
 src/dfChemistryModel/dfChemistryModel.H |  5 ++++-
 2 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/src/dfChemistryModel/dfChemistryModel.C b/src/dfChemistryModel/dfChemistryModel.C
index 3c09f12a..61c3fccf 100644
--- a/src/dfChemistryModel/dfChemistryModel.C
+++ b/src/dfChemistryModel/dfChemistryModel.C
@@ -336,6 +336,14 @@ Foam::dfChemistryModel<ThermoType>::dfChemistryModel
     {
         hc_[i] = CanteraGas_->Hf298SS(i)/CanteraGas_->molecularWeight(i);
     }
+    
+    react_ = std::make_unique<Cantera::Reactor>();
+    react_->setEnergy(0);
+    react_->insert(mixture_.CanteraSolution());
+
+    sim_ = std::make_unique<Cantera::ReactorNet>();
+    sim_->addReactor(*react_);
+    setNumerics(*sim_);  
 }
 
 
@@ -824,7 +832,7 @@ void Foam::dfChemistryModel<ThermoType>::solveSingle
     clockTime time;
     time.timeIncrement();
 
-    Cantera::Reactor react;
+    // Cantera::Reactor react;
     const scalar Ti = problem.Ti;
     const scalar pi = problem.pi;
     const scalar rhoi = problem.rhoi;
@@ -833,14 +841,15 @@ void Foam::dfChemistryModel<ThermoType>::solveSingle
 
     mixture_.setState_TPY(Ti, pi, yPre_.begin());
 
-    react.insert(mixture_.CanteraSolution());
-    // keep T const before and after sim.advance. this will give you a little improvement
-    react.setEnergy(0);
-    Cantera::ReactorNet sim;
-    sim.addReactor(react);
-    setNumerics(sim);
+    // react.insert(mixture_.CanteraSolution());
+    // // keep T const before and after sim.advance. this will give you a little improvement
+    // react.setEnergy(0);
+    // Cantera::ReactorNet sim;
+    // sim.addReactor(react);
+    // setNumerics(sim);
 
-    sim.advance(problem.deltaT);
+    react_->syncState();
+    sim_->advance(problem.deltaT);
 
     CanteraGas_->getMassFractions(yTemp_.begin());
 
@@ -1176,4 +1185,4 @@ Foam::scalar Foam::dfChemistryModel<ThermoType>::solve_CVODE
 #include "pytorchFunctions.H"
 #endif
 
-// ************************************************************************* //
+// ************************************************************************* //
\ No newline at end of file
diff --git a/src/dfChemistryModel/dfChemistryModel.H b/src/dfChemistryModel/dfChemistryModel.H
index 59ea2483..34a4cbb9 100644
--- a/src/dfChemistryModel/dfChemistryModel.H
+++ b/src/dfChemistryModel/dfChemistryModel.H
@@ -94,6 +94,9 @@ public IOdictionary
         CanteraMixture& mixture_;
         std::shared_ptr<Cantera::ThermoPhase> CanteraGas_;
         std::shared_ptr<Cantera::Kinetics> CanteraKinetics_;
+        std::unique_ptr<Cantera::Reactor> react_;
+        std::unique_ptr<Cantera::ReactorNet> sim_;
+
         const fvMesh& mesh_;
         Switch chemistry_;
 
@@ -388,4 +391,4 @@ public:
 
 #endif
 
-// ************************************************************************* //
+// ************************************************************************* //
\ No newline at end of file

From f5f6eba716fcef440b479bb8b3afa202eda457a6 Mon Sep 17 00:00:00 2001
From: xiao312 <xiaoxiao1642@163.com>
Date: Wed, 25 Jun 2025 12:56:49 +0800
Subject: [PATCH 2/2] Bug fix

---
 src/dfChemistryModel/dfChemistryModel.C | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/dfChemistryModel/dfChemistryModel.C b/src/dfChemistryModel/dfChemistryModel.C
index 61c3fccf..b9d6da87 100644
--- a/src/dfChemistryModel/dfChemistryModel.C
+++ b/src/dfChemistryModel/dfChemistryModel.C
@@ -852,6 +852,7 @@ void Foam::dfChemistryModel<ThermoType>::solveSingle
     sim_->advance(problem.deltaT);
 
     CanteraGas_->getMassFractions(yTemp_.begin());
+    sim_->setInitialTime(0.0);
 
     for (int i=0; i<mixture_.nSpecies(); i++)
     {