ENH: cylindricalCS is now in radians only (issue #863)

- this provides internal consistency and allows direct use of the
  coordinate angle with sin(), cos() functions.
  It eliminates potential issues that could otherwise arise from
  alternative user input.

  Eg, in mixerFvMesh it would have previously been possible to specify
  the coordinate system to use degrees or radians, but these units were
  not checked when determining the tangential sweep positions.

NOTE: this may represent a breaking change if user coding has been
relying on cylindrical coordinate system in degrees.

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

@@ -381,7 +381,7 @@ void Foam::fv::rotorDiskSource::createCoordinateSystem()
         }
     }
 
-    coordSys_ = cylindricalCS("rotorCoordSys", origin, axis, refDir, false);
+    coordSys_ = cylindricalCS("rotorCS", origin, axis, refDir);
 
     const scalar sumArea = gSum(area_);
     const scalar diameter = Foam::sqrt(4.0*sumArea/mathematical::pi);
@@ -483,7 +483,7 @@ Foam::fv::rotorDiskSource::rotorDiskSource
     R_(cells_.size(), I),
     invR_(cells_.size(), I),
     area_(cells_.size(), 0.0),
-    coordSys_(false),
+    coordSys_(),
     cylindrical_(),
     rMax_(0.0),
     trim_(trimModel::New(*this, coeffs_)),

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

@@ -196,7 +196,7 @@ protected:
         //- Area [m2]
         List<scalar> area_;
 
-        //- Rotor local cylindrical coordinate system (r, theta, z)
+        //- Rotor local cylindrical coordinate system (r-theta-z)
         cylindricalCS coordSys_;
 
         //- Rotor transformation coordinate system
@@ -279,7 +279,7 @@ public:
             // (Cylindrical r, theta, z)
             inline const List<point>& x() const;
 
-            //- Return the rotor coordinate system (r, theta, z)
+            //- Return the rotor coordinate system (r-theta-z)
             inline const cylindricalCS& coordSys() const;
 
 

src/lagrangian/intermediate/submodels/CloudFunctionObjects/ParticleCollector/ParticleCollector.C

@@ -207,7 +207,7 @@ void Foam::ParticleCollector<CloudType>::initConcentricCircles()
     faces_.setSize(nFace);
     area_.setSize(nFace);
 
-    coordSys_ = cylindricalCS("coordSys", origin, normal_[0], refDir, false);
+    coordSys_ = cylindricalCS("collector", origin, normal_[0], refDir);
 
     List<label> ptIDs(identity(nPointPerRadius));
 
@@ -539,7 +539,7 @@ Foam::ParticleCollector<CloudType>::ParticleCollector
     faceTris_(),
     nSector_(0),
     radius_(),
-    coordSys_(false),
+    coordSys_(),
     normal_(),
     negateParcelsOppositeNormal_
     (

src/mesh/blockMesh/blockEdges/arcEdge/arcEdge.C

@@ -98,8 +98,8 @@ Foam::cylindricalCS Foam::blockEdges::arcEdge::calcAngle()
 
     radius_ = mag(r3);
 
-    // The corresponding local cylindrical coordinate system (degrees)
-    return cylindricalCS("arcEdgeCS", centre, arcAxis, r1, true);
+    // The corresponding local cylindrical coordinate system (radians)
+    return cylindricalCS("arc", centre, arcAxis, r1);
 }
 
 
@@ -158,13 +158,14 @@ Foam::point Foam::blockEdges::arcEdge::position(const scalar lambda) const
         return p3_;
     }
 
-    return cs_.globalPosition(vector(radius_, lambda*angle_, 0.0));
+    // The angle is degrees, the coordinate system in radians
+    return cs_.globalPosition(vector(radius_, degToRad(lambda*angle_), 0));
 }
 
 
 Foam::scalar Foam::blockEdges::arcEdge::length() const
 {
-    return degToRad(angle_*radius_);
+    return degToRad(radius_*angle_);
 }
 
 

src/mesh/blockMesh/blockEdges/arcEdge/arcEdge.H

@@ -64,7 +64,7 @@ class arcEdge
         //- The arc radius
         scalar radius_;
 
-        //- The local cylindrical coordinate system (degrees)
+        //- The local cylindrical coordinate system
         cylindricalCS cs_;
 
 

src/meshTools/coordinate/systems/cylindricalCS.C

@@ -3,7 +3,7 @@
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
     \\  /    A nd           | Copyright (C) 2011-2016 OpenFOAM Foundation
-     \\/     M anipulation  |
+     \\/     M anipulation  | Copyright (C) 2018 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -24,41 +24,69 @@ License
 \*---------------------------------------------------------------------------*/
 
 #include "cylindricalCS.H"
-
-#include "one.H"
-#include "mathematicalConstants.H"
 #include "addToRunTimeSelectionTable.H"
 
+// * * * * * * * * * * * * * * * Local Functions * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+// Issue warning if 'degrees' keyword was specified and true.
+// Compatibility change after 1806.
+
+static inline void warnCompatDegrees(const Foam::dictionary& dict)
+{
+    if (Pstream::parRun() ? Pstream::master() : true)
+    {
+        std::cerr
+            << "--> FOAM IOWarning :" << nl
+            << "    Found [v1806] 'degrees' keyword in dictionary \""
+            << dict.name().c_str() << "\"    Ignored, now radians only." << nl
+            << std::endl;
+    }
+}
+
+
+//- Convert from Cartesian (to Cylindrical)
+static inline vector fromCartesian(const vector& v)
+{
+    return vector(hypot(v.x(), v.y()), atan2(v.y(), v.x()), v.z());
+}
+
+
+//- Convert to Cartesian (from Cylindrical)
+static inline vector toCartesian(const vector& v)
+{
+    return vector(v.x()*cos(v.y()), v.x()*sin(v.y()), v.z());
+}
+
+} // End namespace Foam
+
 
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
-Foam::cylindricalCS::cylindricalCS(const bool inDegrees)
+Foam::cylindricalCS::cylindricalCS()
 :
-    coordinateSystem(),
-    inDegrees_(inDegrees)
+    coordinateSystem()
 {}
 
 
 Foam::cylindricalCS::cylindricalCS
 (
-    const coordinateSystem& cs,
-    const bool inDegrees
+    const coordinateSystem& cs
 )
 :
-    coordinateSystem(cs),
-    inDegrees_(inDegrees)
+    coordinateSystem(cs)
 {}
 
 
 Foam::cylindricalCS::cylindricalCS
 (
     const word& name,
-    const coordinateSystem& cs,
-    const bool inDegrees
+    const coordinateSystem& cs
 )
 :
-    coordinateSystem(name, cs),
-    inDegrees_(inDegrees)
+    coordinateSystem(name, cs)
 {}
 
 
@@ -66,12 +94,10 @@ Foam::cylindricalCS::cylindricalCS
 (
     const word& name,
     const point& origin,
-    const coordinateRotation& cr,
-    const bool inDegrees
+    const coordinateRotation& cr
 )
 :
-    coordinateSystem(name, origin, cr),
-    inDegrees_(inDegrees)
+    coordinateSystem(name, origin, cr)
 {}
 
 
@@ -80,12 +106,10 @@ Foam::cylindricalCS::cylindricalCS
     const word& name,
     const point& origin,
     const vector& axis,
-    const vector& dirn,
-    const bool inDegrees
+    const vector& dirn
 )
 :
-    coordinateSystem(name, origin, axis, dirn),
-    inDegrees_(inDegrees)
+    coordinateSystem(name, origin, axis, dirn)
 {}
 
 
@@ -95,9 +119,13 @@ Foam::cylindricalCS::cylindricalCS
     const dictionary& dict
 )
 :
-    coordinateSystem(name, dict),
-    inDegrees_(dict.lookupOrDefault("degrees", true))
-{}
+    coordinateSystem(name, dict)
+{
+    if (dict.lookupOrDefault("degrees", false))
+    {
+        warnCompatDegrees(dict);
+    }
+}
 
 
 Foam::cylindricalCS::cylindricalCS
@@ -106,45 +134,26 @@ Foam::cylindricalCS::cylindricalCS
     const dictionary& dict
 )
 :
-    coordinateSystem(obr, dict),
-    inDegrees_(dict.lookupOrDefault("degrees", true))
-{}
-
-
-// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
-
-Foam::cylindricalCS::~cylindricalCS()
-{}
+    coordinateSystem(obr, dict)
+{
+    if (dict.lookupOrDefault("degrees", false))
+    {
+        warnCompatDegrees(dict);
+    }
+}
 
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
-bool Foam::cylindricalCS::inDegrees() const
-{
-    return inDegrees_;
-}
-
-
-bool& Foam::cylindricalCS::inDegrees()
-{
-    return inDegrees_;
-}
-
-
 Foam::vector Foam::cylindricalCS::localToGlobal
 (
     const vector& local,
     bool translate
 ) const
 {
-    scalar theta
-    (
-        local.y()*(inDegrees_ ? constant::mathematical::pi/180.0 : 1.0)
-    );
-
     return coordinateSystem::localToGlobal
     (
-        vector(local.x()*cos(theta), local.x()*sin(theta), local.z()),
+        toCartesian(local),
         translate
     );
 }
@@ -156,19 +165,22 @@ Foam::tmp<Foam::vectorField> Foam::cylindricalCS::localToGlobal
     bool translate
 ) const
 {
-    scalarField theta
-    (
-        local.component(vector::Y)
-       *(inDegrees_ ? constant::mathematical::pi/180.0 : 1.0)
-    );
+    const label len = local.size();
 
+    auto tresult = tmp<vectorField>::New(len);
+    auto& result = tresult.ref();
 
-    vectorField lc(local.size());
-    lc.replace(vector::X, local.component(vector::X)*cos(theta));
-    lc.replace(vector::Y, local.component(vector::X)*sin(theta));
-    lc.replace(vector::Z, local.component(vector::Z));
+    for (label i=0; i<len; ++i)
+    {
+        result[i] =
+            coordinateSystem::localToGlobal
+            (
+                toCartesian(local[i]),
+                translate
+            );
+    }
 
-    return coordinateSystem::localToGlobal(lc, translate);
+    return tresult;
 }
 
 
@@ -178,21 +190,10 @@ Foam::vector Foam::cylindricalCS::globalToLocal
     bool translate
 ) const
 {
-    const vector lc
+    return fromCartesian
     (
         coordinateSystem::globalToLocal(global, translate)
     );
-
-    return vector
-    (
-        sqrt(sqr(lc.x()) + sqr(lc.y())),
-        atan2
-        (
-            lc.y(),
-            lc.x()
-        )*(inDegrees_ ? 180.0/constant::mathematical::pi : 1.0),
-        lc.z()
-    );
 }
 
 
@@ -202,31 +203,18 @@ Foam::tmp<Foam::vectorField> Foam::cylindricalCS::globalToLocal
     bool translate
 ) const
 {
-    const vectorField lc
+    const label len = global.size();
+
+    tmp<vectorField> tresult
     (
         coordinateSystem::globalToLocal(global, translate)
     );
+    auto& result = tresult.ref();
 
-    tmp<vectorField> tresult(new vectorField(lc.size()));
-    vectorField& result = tresult.ref();
-
-    result.replace
-    (
-        vector::X,
-        sqrt(sqr(lc.component(vector::X)) + sqr(lc.component(vector::Y)))
-    );
-
-    result.replace
-    (
-        vector::Y,
-        atan2
-        (
-            lc.component(vector::Y),
-            lc.component(vector::X)
-        )*(inDegrees_ ? 180.0/constant::mathematical::pi : 1.0)
-    );
-
-    result.replace(vector::Z, lc.component(vector::Z));
+    for (label i=0; i<len; ++i)
+    {
+        result[i] = fromCartesian(result[i]);
+    }
 
     return tresult;
 }

src/meshTools/coordinate/systems/cylindricalCS.H

@@ -3,7 +3,7 @@
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
     \\  /    A nd           | Copyright (C) 2011-2014 OpenFOAM Foundation
-     \\/     M anipulation  |
+     \\/     M anipulation  | Copyright (C) 2018 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -25,7 +25,7 @@ Class
     Foam::cylindricalCS
 
 Description
-    Cylindrical coordinate system
+    Cylindrical coordinate system, always in radians.
 
 SourceFiles
     cylindricalCS.C
@@ -50,12 +50,6 @@ class cylindricalCS
 :
     public coordinateSystem
 {
-    // Private data members
-
-        //- Are angles in degrees? (default = true)
-        bool inDegrees_;
-
-
 protected:
 
     // Protected Member Functions
@@ -92,21 +86,19 @@ public:
     // Constructors
 
         //- Construct null
-        cylindricalCS(const bool inDegrees=true);
+        cylindricalCS();
 
         //- Construct copy
         cylindricalCS
         (
-            const coordinateSystem&,
-            const bool inDegrees=true
+            const coordinateSystem&
         );
 
         //- Construct copy with a different name
         cylindricalCS
         (
             const word& name,
-            const coordinateSystem&,
-            const bool inDegrees=true
+            const coordinateSystem&
         );
 
         //- Construct from origin and rotation
@@ -114,8 +106,7 @@ public:
         (
             const word& name,
             const point& origin,
-            const coordinateRotation&,
-            const bool inDegrees=true
+            const coordinateRotation&
         );
 
         //- Construct from origin and 2 axes
@@ -124,8 +115,7 @@ public:
             const word& name,
             const point& origin,
             const vector& axis,
-            const vector& dirn,
-            const bool inDegrees=true
+            const vector& dirn
         );
 
         //- Construct from dictionary and name
@@ -136,16 +126,7 @@ public:
 
 
     //- Destructor
-    virtual ~cylindricalCS();
-
-
-    // Member Functions
-
-        //- Are angles in degrees?
-        bool inDegrees() const;
-
-        //- Non-const access to inDegrees
-        bool& inDegrees();
+    virtual ~cylindricalCS() = default;
 };
 
 

src/topoChangerFvMesh/mixerFvMesh/mixerFvMesh.C

@@ -269,13 +269,10 @@ Foam::mixerFvMesh::mixerFvMesh
     ),
     csPtr_
     (
-        coordinateSystem::New
-        (
-            "coordinateSystem",
-            motionDict_.subDict("coordinateSystem")
-        )
+        // Caution: must be a cylindricalCS
+        coordinateSystem::New(*this, motionDict_, "coordinateSystem")
     ),
-    rpm_(readScalar(motionDict_.lookup("rpm"))),
+    rpm_(motionDict_.get<scalar>("rpm")),
     movingPointsMaskPtr_(nullptr)
 {
     addZonesAndModifiers();
@@ -294,6 +291,7 @@ Foam::mixerFvMesh::~mixerFvMesh()
     deleteDemandDrivenData(movingPointsMaskPtr_);
 }
 
+
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 // Return moving points mask.  Moving points marked with 1
@@ -310,13 +308,15 @@ const Foam::scalarField& Foam::mixerFvMesh::movingPointsMask() const
 
 bool Foam::mixerFvMesh::update()
 {
-    // Rotational speed needs to be converted from rpm
+    // The tangential sweep (radians)
+    const vector theta(0, rpmToRads(rpm_)*time().deltaTValue(), 0);
+
     movePoints
     (
         csPtr_->globalPosition
         (
             csPtr_->localPosition(points())
-          + vector(0, rpm_*360.0*time().deltaTValue()/60.0, 0)
+          + theta
             *movingPointsMask()
         )
     );
@@ -339,7 +339,7 @@ bool Foam::mixerFvMesh::update()
         csPtr_->globalPosition
         (
             csPtr_->localPosition(oldPoints())
-          + vector(0, rpm_*360.0*time().deltaTValue()/60.0, 0)
+          + theta
             *movingPointsMask()
         )
     );