From c6eea6990fed7afc82b42f368902898e6dde1ecb Mon Sep 17 00:00:00 2001
From: Henry <Henry>
Date: Thu, 4 Oct 2012 18:10:26 +0100
Subject: [PATCH] specieThermo: Add guard in K(T) to protect against 0 moles in
 composition

---
 .../specie/thermo/thermo/thermoI.H              | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/thermophysicalModels/specie/thermo/thermo/thermoI.H b/src/thermophysicalModels/specie/thermo/thermo/thermoI.H
index b8642e960b..21a58ec779 100644
--- a/src/thermophysicalModels/specie/thermo/thermo/thermoI.H
+++ b/src/thermophysicalModels/specie/thermo/thermo/thermoI.H
@@ -298,15 +298,22 @@ template<class Thermo, template<class> class Type>
 inline Foam::scalar
 Foam::species::thermo<Thermo, Type>::K(const scalar p, const scalar T) const
 {
-    scalar arg = -this->nMoles()*this->g(p, T)/(this->RR*T);
-
-    if (arg < 600.0)
+    if (equal(this->nMoles(), SMALL))
     {
-        return ::exp(arg);
+        return 1.0;
     }
     else
     {
-        return VGREAT;
+        scalar arg = -this->nMoles()*this->g(p, T)/(this->RR*T);
+
+        if (arg < 600.0)
+        {
+            return exp(arg);
+        }
+        else
+        {
+            return VGREAT;
+        }
     }
 }