ENH: avoid duplicate bookkeeping of rotation tensors in rotorDiskSource

src/fvOptions/sources/derived/rotorDiskSource/rotorDiskSource.C

@@ -422,8 +422,7 @@ void Foam::fv::rotorDiskSource::constructGeometry()
             // rotor cone system
             scalar c = cos(beta);
             scalar s = sin(beta);
-            R_[i] = tensor(c, 0, -s, 0, 1, 0, s, 0, c);
-            invR_[i] = R_[i].T();
+            Rcone_[i] = tensor(c, 0, -s, 0, 1, 0, s, 0, c);
         }
     }
 }
@@ -480,9 +479,8 @@ Foam::fv::rotorDiskSource::rotorDiskSource
     tipEffect_(1.0),
     flap_(),
     x_(cells_.size(), Zero),
-    R_(cells_.size(), I),
-    invR_(cells_.size(), I),
-    area_(cells_.size(), 0.0),
+    Rcone_(cells_.size(), I),
+    area_(cells_.size(), Zero),
     coordSys_(),
     cylindrical_(),
     rMax_(0.0),

src/fvOptions/sources/derived/rotorDiskSource/rotorDiskSource.H

@@ -188,10 +188,7 @@ protected:
         List<point> x_;
 
         //- Rotation tensor for flap angle
-        List<tensor> R_;
-
-        //- Inverse rotation tensor for flap angle
-        List<tensor> invR_;
+        List<tensor> Rcone_;
 
         //- Area [m2]
         List<scalar> area_;

src/fvOptions/sources/derived/rotorDiskSource/rotorDiskSourceTemplates.C

@@ -26,6 +26,7 @@ License
 #include "rotorDiskSource.H"
 #include "volFields.H"
 #include "unitConversion.H"
+#include "transform.H"
 
 using namespace Foam::constant;
 
@@ -62,7 +63,7 @@ void Foam::fv::rotorDiskSource::calculate
             vector Uc = cylindrical_->invTransform(U[celli], i);
 
             // Transform velocity into local coning system
-            Uc = R_[i] & Uc;
+            Uc = transform(Rcone_[i], Uc);
 
             // Set radial component of velocity to zero
             Uc.x() = 0.0;
@@ -129,7 +130,7 @@ void Foam::fv::rotorDiskSource::calculate
             liftEff += rhoRef_*localForce.z();
 
             // Transform force from local coning system into rotor cylindrical
-            localForce = invR_[i] & localForce;
+            localForce = invTransform(Rcone_[i], localForce);
 
             // Transform force into global Cartesian co-ordinate system
             force[celli] = cylindrical_->transform(localForce, i);