From ee6a53adeea80cc37d6d0ef31b3f2dd6b9711cff Mon Sep 17 00:00:00 2001
From: Henry Weller <http://openfoam.org>
Date: Tue, 12 Jun 2018 10:11:50 +0100
Subject: [PATCH] seulex: Reverting change to stability/monotonicity check

This change cause some cases to fail, in particular
tutorials/lagrangian/sprayFoam/aachenBomb

Reopened https://bugs.openfoam.org/view.php?id=2972
---
 src/ODE/ODESolvers/seulex/seulex.C | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/ODE/ODESolvers/seulex/seulex.C b/src/ODE/ODESolvers/seulex/seulex.C
index 4df64c6c1..643c1c8fc 100644
--- a/src/ODE/ODESolvers/seulex/seulex.C
+++ b/src/ODE/ODESolvers/seulex/seulex.C
@@ -153,7 +153,8 @@ bool Foam::seulex::seul
 
             LUBacksubstitute(a_, pivotIndices_, dy_);
 
-            const scalar denom = max(1, dy1);
+            // const scalar denom = max(1, dy1);
+            const scalar denom = min(1, dy1 + small);
             scalar dy2 = 0;
             for (label i=0; i<n_; i++)
             {
@@ -286,7 +287,7 @@ void Foam::seulex::solve
         if (mag(dx) <= mag(x)*sqr(small))
         {
              WarningInFunction
-                    << "step size underflow :"  << dx << endl;
+                 << "step size underflow :"  << dx << endl;
         }
 
         scalar errOld = 0;