diff --git a/src/thermophysicalModels/basic/basicThermo/basicThermo.H b/src/thermophysicalModels/basic/basicThermo/basicThermo.H
index 92be7a6008..8ba800e661 100644
--- a/src/thermophysicalModels/basic/basicThermo/basicThermo.H
+++ b/src/thermophysicalModels/basic/basicThermo/basicThermo.H
@@ -405,32 +405,35 @@ public:
             //- Thermal diffusivity for temperature of mixture [J/m/s/K]
             virtual tmp<volScalarField> kappa() const = 0;
 
-            //- Thermal diffusivity of mixture for patch [J/m/s/K]
+            //- Thermal diffusivity for temperature
+            //  of mixture for patch [J/m/s/K]
             virtual tmp<scalarField> kappa
             (
                 const label patchi
             ) const = 0;
 
-            //- Effective thermal diffusivity of mixture [J/m/s/K]
+            //- Effective thermal diffusivity for temperature
+            //  of mixture [J/m/s/K]
             virtual tmp<volScalarField> kappaEff
             (
                 const volScalarField&
             ) const = 0;
 
-            //- Effective thermal diffusivity of mixture for patch [J/m/s/K]
+            //- Effective thermal diffusivity for temperature
+            //  of mixture for patch [J/m/s/K]
             virtual tmp<scalarField> kappaEff
             (
                 const scalarField& alphat,
                 const label patchi
             ) const = 0;
 
-            //- Effective thermal diffusivity of mixture [J/m/s/K]
+            //- Effective thermal diffusivity of mixture [kg/m/s]
             virtual tmp<volScalarField> alphaEff
             (
                 const volScalarField& alphat
             ) const = 0;
 
-            //- Effective thermal diffusivity of mixture for patch [J/m/s/K]
+            //- Effective thermal diffusivity of mixture for patch [kg/m/s]
             virtual tmp<scalarField> alphaEff
             (
                 const scalarField& alphat,
diff --git a/src/thermophysicalModels/basic/heThermo/heThermo.H b/src/thermophysicalModels/basic/heThermo/heThermo.H
index c227769b6c..a07a7ecfeb 100644
--- a/src/thermophysicalModels/basic/heThermo/heThermo.H
+++ b/src/thermophysicalModels/basic/heThermo/heThermo.H
@@ -259,30 +259,32 @@ public:
             //- Thermal diffusivity for temperature of mixture [J/m/s/K]
             virtual tmp<volScalarField> kappa() const;
 
-            //- Thermal diffusivity of mixture for patch [J/m/s/K]
+            //- Thermal diffusivity for temperature
+            //  of mixture for patch [J/m/s/K]
             virtual tmp<scalarField> kappa
             (
                 const label patchi
             ) const;
 
-            //- Effective thermal diffusivity of mixture [J/m/s/K]
+            //- Effective thermal diffusivity for temperature
+            //  of mixture [J/m/s/K]
             virtual tmp<volScalarField> kappaEff(const volScalarField&) const;
 
-            //- Effective thermal diffusivity of mixture for patch [J/m/s/K]
+            //- Effective thermal diffusivity for temperature
+            //  of mixture for patch [J/m/s/K]
             virtual tmp<scalarField> kappaEff
             (
                 const scalarField& alphat,
                 const label patchi
             ) const;
 
-
-            //- Effective thermal diffusivity of mixture [J/m/s/K]
+            //- Effective thermal diffusivity of mixture [kg/m/s]
             virtual tmp<volScalarField> alphaEff
             (
                 const volScalarField& alphat
             ) const;
 
-            //- Effective thermal diffusivity of mixture for patch [J/m/s/K]
+            //- Effective thermal diffusivity of mixture for patch [kg/m/s]
             virtual tmp<scalarField> alphaEff
             (
                 const scalarField& alphat,