rhoCentralFoam: corrected reading of Pr

applications/solvers/compressible/rhoCentralFoam/readThermophysicalProperties.H

@@ -16,11 +16,8 @@ IOdictionary thermophysicalProperties
 
 dimensionedScalar Pr
 (
-    dimensionedScalar::lookupOrDefault
-    (
-        "Pr",
-        thermophysicalProperties,
-        1.0
-    )
+    "Pr",
+    dimless,
+    thermophysicalProperties.subDict("mixture").subDict("transport")
+   .lookup("Pr")
 );
-