diff --git a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/BirdCarreau/BirdCarreau.C b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/BirdCarreau/BirdCarreau.C
index fb00baacce..c22ad783b1 100644
--- a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/BirdCarreau/BirdCarreau.C
+++ b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/BirdCarreau/BirdCarreau.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2018-2021 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2018-2022 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -81,24 +81,19 @@ read
     const dictionary& coeffs =
         viscosityProperties.optionalSubDict(typeName + "Coeffs");
 
-    coeffs.lookup("nuInf") >> nuInf_;
+    nuInf_.read(coeffs);;
 
     if (coeffs.found("tauStar"))
     {
-        coeffs.lookup("tauStar") >> tauStar_;
+        tauStar_.read(coeffs);
     }
     else
     {
-        coeffs.lookup("k") >> k_;
+        k_.read(coeffs);
     }
 
-    coeffs.lookup("n") >> n_;
-
-    a_ = coeffs.lookupOrDefault
-    (
-        "a",
-        dimensionedScalar("a", dimless, 2)
-    );
+    n_.read(coeffs);
+    a_.read(coeffs);
 
     return true;
 }
diff --git a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/Casson/Casson.C b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/Casson/Casson.C
index cc1e342cda..c1f4d93adb 100644
--- a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/Casson/Casson.C
+++ b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/Casson/Casson.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2018-2021 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2018-2022 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -78,10 +78,10 @@ bool Foam::laminarModels::generalisedNewtonianViscosityModels::Casson::read
     const dictionary& coeffs =
         viscosityProperties.optionalSubDict(typeName + "Coeffs");
 
-    coeffs.lookup("m") >> m_;
-    coeffs.lookup("tau0") >> tau0_;
-    coeffs.lookup("nuMin_") >> nuMin_;
-    coeffs.lookup("nuMax_") >> nuMax_;
+    m_.read(coeffs);
+    tau0_.read(coeffs);
+    nuMin_.read(coeffs);
+    nuMax_.read(coeffs);
 
     return true;
 }
diff --git a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/CrossPowerLaw/CrossPowerLaw.C b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/CrossPowerLaw/CrossPowerLaw.C
index 15a942b7fb..58d9243102 100644
--- a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/CrossPowerLaw/CrossPowerLaw.C
+++ b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/CrossPowerLaw/CrossPowerLaw.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2018-2021 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2018-2022 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -81,18 +81,18 @@ read
     const dictionary& coeffs =
         viscosityProperties.optionalSubDict(typeName + "Coeffs");
 
-    coeffs.lookup("nuInf") >> nuInf_;
+    nuInf_.read(coeffs);
 
     if (coeffs.found("tauStar"))
     {
-        coeffs.lookup("tauStar") >> tauStar_;
+        tauStar_.read(coeffs);
     }
     else
     {
-        coeffs.lookup("m") >> m_;
+        m_.read(coeffs);
     }
 
-    coeffs.lookup("n") >> n_;
+    n_.read(coeffs);
 
     return true;
 }
diff --git a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/HerschelBulkley/HerschelBulkley.C b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/HerschelBulkley/HerschelBulkley.C
index 8fe8781817..dc7c092984 100644
--- a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/HerschelBulkley/HerschelBulkley.C
+++ b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/HerschelBulkley/HerschelBulkley.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2018-2021 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2018-2022 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -80,9 +80,9 @@ HerschelBulkley::read
     const dictionary& coeffs =
         viscosityProperties.optionalSubDict(typeName + "Coeffs");
 
-    coeffs.lookup("k") >> k_;
-    coeffs.lookup("n") >> n_;
-    coeffs.lookup("tau0") >> tau0_;
+    k_.read(coeffs);
+    n_.read(coeffs);
+    tau0_.read(coeffs);
 
     return true;
 }
diff --git a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/powerLaw/powerLaw.C b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/powerLaw/powerLaw.C
index 6d59f5bc6c..2a2a888a9e 100644
--- a/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/powerLaw/powerLaw.C
+++ b/src/MomentumTransportModels/momentumTransportModels/laminar/generalisedNewtonian/generalisedNewtonianViscosityModels/strainRateViscosityModels/powerLaw/powerLaw.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2018-2021 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2018-2022 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -79,10 +79,10 @@ bool Foam::laminarModels::generalisedNewtonianViscosityModels::powerLaw::read
     const dictionary& coeffs =
         viscosityProperties.optionalSubDict(typeName + "Coeffs");
 
-    coeffs.lookup("k") >> k_;
-    coeffs.lookup("n") >> n_;
-    coeffs.lookup("nuMin") >> nuMin_;
-    coeffs.lookup("nuMax") >> nuMax_;
+    k_.read(coeffs);
+    n_.read(coeffs);
+    nuMin_.read(coeffs);
+    nuMax_.read(coeffs);
 
     return true;
 }