From c26f08d819d1419855426744777a36f72ddde48b Mon Sep 17 00:00:00 2001
From: John <colemanjs@ornl.gov>
Date: Mon, 23 Jun 2025 10:57:47 -0400
Subject: [PATCH] added implicit temperature limiting, accessible through
 PIMPLE dictionary in fvSolution

---
 applications/solvers/additiveFoam/solutionControls.H |  7 +++++++
 applications/solvers/additiveFoam/thermo/TEqn.H      | 10 +++++++++-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/applications/solvers/additiveFoam/solutionControls.H b/applications/solvers/additiveFoam/solutionControls.H
index 94c5336c..4c26ab4a 100644
--- a/applications/solvers/additiveFoam/solutionControls.H
+++ b/applications/solvers/additiveFoam/solutionControls.H
@@ -5,6 +5,13 @@ scalar nThermoCorr =
 scalar thermoTol = 
     pimple.dict().lookupOrDefault<scalar>("thermoTolerance", 1e-6);
 
+dimensionedScalar Tmax
+(
+    "Tmax",
+    T.dimensions(),
+    pimple.dict().lookupOrDefault<scalar>("Tmax", vGreat)
+);
+
 // Integrate the total power input to domain
 const scalar totalPower = fvc::domainIntegrate(sources.qDot()).value();
 
diff --git a/applications/solvers/additiveFoam/thermo/TEqn.H b/applications/solvers/additiveFoam/thermo/TEqn.H
index ee58df87..4c22f5d9 100644
--- a/applications/solvers/additiveFoam/thermo/TEqn.H
+++ b/applications/solvers/additiveFoam/thermo/TEqn.H
@@ -20,10 +20,18 @@
     {
         #include "thermo/thermoSource.H"
 
+        //- optional implicit limiting of temperature field
+        volScalarField A
+        (
+            "A",
+            dimensionedScalar(rho.dimensions()*Cp.dimensions(), 1e15)
+           *pos(T - Tmax)
+        );
+        
         //- solve the energy equation
         solve
         (
-            TEqn
+            TEqn + rDeltaT*(fvm::Sp(A, T) - A*Tmax)
          ==
             (
                 (ddtScheme == "Euler")