diff --git a/applications/solvers/acoustic/acousticFoam/readTransportProperties.H b/applications/solvers/acoustic/acousticFoam/readTransportProperties.H
index 5ff526af53..ec83492534 100644
--- a/applications/solvers/acoustic/acousticFoam/readTransportProperties.H
+++ b/applications/solvers/acoustic/acousticFoam/readTransportProperties.H
@@ -18,6 +18,6 @@ dimensionedScalar rho("rho", dimDensity, transportProperties);
 
 scalar MaxCo =
     max(mesh.surfaceInterpolation::deltaCoeffs()*c0).value()
-   *runTime.deltaT().value();
+   *runTime.deltaTValue();
 
 Info<< "Max acoustic Courant Number = " << MaxCo << endl;
diff --git a/applications/solvers/combustion/chemFoam/setDeltaT.H b/applications/solvers/combustion/chemFoam/setDeltaT.H
index 52407c9475..ef50a97026 100644
--- a/applications/solvers/combustion/chemFoam/setDeltaT.H
+++ b/applications/solvers/combustion/chemFoam/setDeltaT.H
@@ -1,5 +1,5 @@
 if (adjustTimeStep)
 {
     runTime.setDeltaT(min(dtChem, maxDeltaT));
-    Info<< "deltaT = " <<  runTime.deltaT().value() << endl;
+    Info<< "deltaT = " <<  runTime.deltaTValue() << endl;
 }
diff --git a/applications/solvers/combustion/chemFoam/solveChemistry.H b/applications/solvers/combustion/chemFoam/solveChemistry.H
index e32a1ab0bd..856ccab1d6 100644
--- a/applications/solvers/combustion/chemFoam/solveChemistry.H
+++ b/applications/solvers/combustion/chemFoam/solveChemistry.H
@@ -1,3 +1,3 @@
-dtChem = chemistry.solve(runTime.deltaT().value());
+dtChem = chemistry.solve(runTime.deltaTValue());
 scalar Qdot = chemistry.Qdot()()[0]/rho[0];
-integratedHeat += Qdot*runTime.deltaT().value();
+integratedHeat += Qdot*runTime.deltaTValue();
diff --git a/applications/solvers/finiteArea/liquidFilmFoam/capillaryCourantNo.H b/applications/solvers/finiteArea/liquidFilmFoam/capillaryCourantNo.H
index f4e87630e0..6973f17483 100644
--- a/applications/solvers/finiteArea/liquidFilmFoam/capillaryCourantNo.H
+++ b/applications/solvers/finiteArea/liquidFilmFoam/capillaryCourantNo.H
@@ -7,7 +7,7 @@
             *mag(aMesh.edgeInterpolation::deltaCoeffs())
             /rhol
         )
-    ).value()*runTime.deltaT().value();
+    ).value()*runTime.deltaTValue();
 
     Info<< "Max Capillary Courant Number = " << CoNumSigma << '\n' << endl;
 }
diff --git a/applications/solvers/finiteArea/liquidFilmFoam/surfaceCourantNo.H b/applications/solvers/finiteArea/liquidFilmFoam/surfaceCourantNo.H
index 8944e3ecba..04a30557c7 100644
--- a/applications/solvers/finiteArea/liquidFilmFoam/surfaceCourantNo.H
+++ b/applications/solvers/finiteArea/liquidFilmFoam/surfaceCourantNo.H
@@ -47,10 +47,10 @@ if (aMesh.nInternalEdges())
     );
 
     CoNum = max(SfUfbyDelta/aMesh.magLe())
-        .value()*runTime.deltaT().value();
+        .value()*runTime.deltaTValue();
 
     meanCoNum = (sum(SfUfbyDelta)/sum(aMesh.magLe()))
-        .value()*runTime.deltaT().value();
+        .value()*runTime.deltaTValue();
 
     velMag = max(mag(phis)/aMesh.magLe()).value();
 }
diff --git a/applications/solvers/heatTransfer/chtMultiRegionFoam/include/setInitialMultiRegionDeltaT.H b/applications/solvers/heatTransfer/chtMultiRegionFoam/include/setInitialMultiRegionDeltaT.H
index b120e5c3d0..09f4a717a9 100644
--- a/applications/solvers/heatTransfer/chtMultiRegionFoam/include/setInitialMultiRegionDeltaT.H
+++ b/applications/solvers/heatTransfer/chtMultiRegionFoam/include/setInitialMultiRegionDeltaT.H
@@ -49,11 +49,11 @@ if (adjustTimeStep)
         (
             min
             (
-                min(maxCo/CoNum, maxDi/DiNum)*runTime.deltaT().value(),
+                min(maxCo/CoNum, maxDi/DiNum)*runTime.deltaTValue(),
                 min(runTime.deltaTValue(), maxDeltaT)
             )
         );
-        Info<< "deltaT = " <<  runTime.deltaT().value() << endl;
+        Info<< "deltaT = " <<  runTime.deltaTValue() << endl;
     }
 }
 
diff --git a/applications/solvers/heatTransfer/chtMultiRegionFoam/include/setMultiRegionDeltaT.H b/applications/solvers/heatTransfer/chtMultiRegionFoam/include/setMultiRegionDeltaT.H
index 4f076d2e69..8eed82dd5c 100644
--- a/applications/solvers/heatTransfer/chtMultiRegionFoam/include/setMultiRegionDeltaT.H
+++ b/applications/solvers/heatTransfer/chtMultiRegionFoam/include/setMultiRegionDeltaT.H
@@ -59,12 +59,12 @@ if (adjustTimeStep)
     (
         min
         (
-            min(deltaTFluid, maxDeltaTSolid)*runTime.deltaT().value(),
+            min(deltaTFluid, maxDeltaTSolid)*runTime.deltaTValue(),
             maxDeltaT
         )
     );
 
-    Info<< "deltaT = " <<  runTime.deltaT().value() << endl;
+    Info<< "deltaT = " <<  runTime.deltaTValue() << endl;
 }
 
 // ************************************************************************* //
diff --git a/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.C b/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.C
index 4f3d9c75fc..77d276973f 100644
--- a/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.C
+++ b/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.C
@@ -1075,7 +1075,7 @@ void Foam::multiphaseMixtureThermo::solveAlphas
 
         MULES::limit
         (
-            1.0/mesh_.time().deltaT().value(),
+            1.0/mesh_.time().deltaTValue(),
             geometricOneField(),
             alpha,
             phi_,
diff --git a/applications/solvers/multiphase/icoReactingMultiphaseInterFoam/laserDTRM/laserDTRM.C b/applications/solvers/multiphase/icoReactingMultiphaseInterFoam/laserDTRM/laserDTRM.C
index f27015326b..ae930a1e39 100644
--- a/applications/solvers/multiphase/icoReactingMultiphaseInterFoam/laserDTRM/laserDTRM.C
+++ b/applications/solvers/multiphase/icoReactingMultiphaseInterFoam/laserDTRM/laserDTRM.C
@@ -699,7 +699,7 @@ void Foam::radiation::laserDTRM::calculate()
         scalar totalQ = gSum(Q_.primitiveFieldRef()*mesh_.V());
         Info << "Total energy absorbed [W]: " << totalQ << endl;
 
-        if (mesh_.time().outputTime())
+        if (mesh_.time().writeTime())
         {
             reflectingCellsVol.write();
             nHat.write();
diff --git a/applications/solvers/multiphase/interCondensatingEvaporatingFoam/temperaturePhaseChangeTwoPhaseMixtures/constant/constant.C b/applications/solvers/multiphase/interCondensatingEvaporatingFoam/temperaturePhaseChangeTwoPhaseMixtures/constant/constant.C
index 78400b60ff..8f1fb0f883 100644
--- a/applications/solvers/multiphase/interCondensatingEvaporatingFoam/temperaturePhaseChangeTwoPhaseMixtures/constant/constant.C
+++ b/applications/solvers/multiphase/interCondensatingEvaporatingFoam/temperaturePhaseChangeTwoPhaseMixtures/constant/constant.C
@@ -124,7 +124,7 @@ Foam::temperaturePhaseChangeTwoPhaseMixtures::constant::mDot() const
       * max(TSat - T, T0)
     );
 
-    if (mesh_.time().outputTime())
+    if (mesh_.time().writeTime())
     {
         mDotC.write();
         mDotE.write();
diff --git a/applications/solvers/multiphase/interFoam/interMixingFoam/alphaEqn.H b/applications/solvers/multiphase/interFoam/interMixingFoam/alphaEqn.H
index 36c7aa00fe..2909b2e8e9 100644
--- a/applications/solvers/multiphase/interFoam/interMixingFoam/alphaEqn.H
+++ b/applications/solvers/multiphase/interFoam/interMixingFoam/alphaEqn.H
@@ -96,7 +96,7 @@
             MULES::limiter
             (
                 allLambda,
-                1.0/runTime.deltaT().value(),
+                1.0/runTime.deltaTValue(),
                 geometricOneField(),
                 alpha1,
                 alphaPhi1BD,
@@ -164,7 +164,7 @@
             MULES::limiter
             (
                 allLambda,
-                1.0/runTime.deltaT().value(),
+                1.0/runTime.deltaTValue(),
                 geometricOneField(),
                 alpha2,
                 alphaPhi2BD,
diff --git a/applications/solvers/multiphase/multiphaseInterFoam/multiphaseMixture/multiphaseMixture.C b/applications/solvers/multiphase/multiphaseInterFoam/multiphaseMixture/multiphaseMixture.C
index 7fefaa1642..9c6ff5d331 100644
--- a/applications/solvers/multiphase/multiphaseInterFoam/multiphaseMixture/multiphaseMixture.C
+++ b/applications/solvers/multiphase/multiphaseInterFoam/multiphaseMixture/multiphaseMixture.C
@@ -628,7 +628,7 @@ void Foam::multiphaseMixture::solveAlphas
 
         MULES::limit
         (
-            1.0/mesh_.time().deltaT().value(),
+            1.0/mesh_.time().deltaTValue(),
             geometricOneField(),
             alpha,
             phi_,
diff --git a/applications/solvers/stressAnalysis/solidDisplacementFoam/readMechanicalProperties.H b/applications/solvers/stressAnalysis/solidDisplacementFoam/readMechanicalProperties.H
index b1f35b15ff..9b116afb1a 100644
--- a/applications/solvers/stressAnalysis/solidDisplacementFoam/readMechanicalProperties.H
+++ b/applications/solvers/stressAnalysis/solidDisplacementFoam/readMechanicalProperties.H
@@ -20,7 +20,7 @@
     IOobject rhoIO
     (
         "rho",
-        runTime.timeName(0),
+        Time::timeName(0),
         mesh,
         IOobject::NO_READ,
         IOobject::NO_WRITE
@@ -75,7 +75,7 @@
     IOobject EHeader
     (
         "E",
-        runTime.timeName(0),
+        Time::timeName(0),
         mesh,
         IOobject::NO_READ,
         IOobject::NO_WRITE
@@ -127,7 +127,7 @@
     IOobject nuIO
     (
         "nu",
-        runTime.timeName(0),
+        Time::timeName(0),
         mesh,
         IOobject::NO_READ,
         IOobject::NO_WRITE
diff --git a/applications/solvers/stressAnalysis/solidDisplacementFoam/readThermalProperties.H b/applications/solvers/stressAnalysis/solidDisplacementFoam/readThermalProperties.H
index 98711e36c4..e1e77e0939 100644
--- a/applications/solvers/stressAnalysis/solidDisplacementFoam/readThermalProperties.H
+++ b/applications/solvers/stressAnalysis/solidDisplacementFoam/readThermalProperties.H
@@ -51,7 +51,7 @@ if (thermalStress)
     IOobject CIO
     (
         "C",
-        runTime.timeName(0),
+        Time::timeName(0),
         mesh,
         IOobject::NO_READ,
         IOobject::NO_WRITE
@@ -106,7 +106,7 @@ if (thermalStress)
     IOobject rhoKIO
     (
         "k",
-        runTime.timeName(0),
+        Time::timeName(0),
         mesh,
         IOobject::NO_READ,
         IOobject::NO_WRITE
@@ -161,7 +161,7 @@ if (thermalStress)
     IOobject alphaIO
     (
         "alpha",
-        runTime.timeName(0),
+        Time::timeName(0),
         mesh,
         IOobject::NO_READ,
         IOobject::NO_WRITE
diff --git a/src/OpenFOAM/db/Time/Time.C b/src/OpenFOAM/db/Time/Time.C
index 1df4fcee23..2549167fe7 100644
--- a/src/OpenFOAM/db/Time/Time.C
+++ b/src/OpenFOAM/db/Time/Time.C
@@ -73,7 +73,7 @@ Foam::Time::writeControlNames
 });
 
 
-Foam::Time::fmtflags Foam::Time::format_(Foam::Time::general);
+Foam::Time::fmtflags Foam::Time::format_(Foam::Time::fmtflags::general);
 
 int Foam::Time::precision_(6);
 
@@ -777,19 +777,13 @@ Foam::Time::~Time()
 Foam::word Foam::Time::timeName(const scalar t, const int precision)
 {
     std::ostringstream buf;
-    buf.setf(ios_base::fmtflags(format_), ios_base::floatfield);
+    buf.setf(std::ios_base::fmtflags(format_), std::ios_base::floatfield);
     buf.precision(precision);
     buf << t;
     return buf.str();
 }
 
 
-Foam::word Foam::Time::timeName() const
-{
-    return dimensionedScalar::name();
-}
-
-
 Foam::word Foam::Time::findInstance
 (
     const fileName& dir,
@@ -1003,18 +997,14 @@ bool Foam::Time::isAdjustTimeStep() const
 
 void Foam::Time::setTime(const Time& t)
 {
-    value() = t.value();
-    dimensionedScalar::name() = t.dimensionedScalar::name();
-    timeIndex_ = t.timeIndex_;
+    resetTimeState(t.timeName(), t.value(), t.timeIndex());
     fileHandler().setTime(*this);
 }
 
 
 void Foam::Time::setTime(const instant& inst, const label newIndex)
 {
-    value() = inst.value();
-    dimensionedScalar::name() = inst.name();
-    timeIndex_ = newIndex;
+    resetTimeState(inst.name(), inst.value(), newIndex);
 
     IOdictionary timeDict
     (
@@ -1045,9 +1035,12 @@ void Foam::Time::setTime(const dimensionedScalar& newTime, const label newIndex)
 
 void Foam::Time::setTime(const scalar newTime, const label newIndex)
 {
-    value() = newTime;
-    dimensionedScalar::name() = timeName(timeToUserTime(newTime));
-    timeIndex_ = newIndex;
+    resetTimeState
+    (
+        timeName(timeToUserTime(newTime)),
+        newTime,
+        newIndex
+    );
     fileHandler().setTime(*this);
 }
 
diff --git a/src/OpenFOAM/db/Time/Time.H b/src/OpenFOAM/db/Time/Time.H
index ad28409a43..2b07d333f7 100644
--- a/src/OpenFOAM/db/Time/Time.H
+++ b/src/OpenFOAM/db/Time/Time.H
@@ -347,7 +347,17 @@ public:
 
     // Member Functions
 
-        // Database functions
+    // TimeState Functions
+
+        //- Return the current time name
+        using TimeState::timeName;
+
+        //- Return a time name for the given scalar time value
+        //- formatted with the given precision
+        static word timeName(const scalar t, const int precision = precision_);
+
+
+        // Database Functions
 
             //- Return name from objectRegistry and not TimePaths
             using objectRegistry::name;
@@ -365,7 +375,7 @@ public:
             }
 
             //- Return read access to the controlDict dictionary
-            const dictionary& controlDict() const
+            const dictionary& controlDict() const noexcept
             {
                 return controlDict_;
             }
@@ -487,17 +497,6 @@ public:
 
         // Access
 
-            //- Return time name of given scalar time
-            //- formatted with the given precision
-            static word timeName
-            (
-                const scalar t,
-                const int precision = precision_
-            );
-
-            //- Return current time name
-            virtual word timeName() const;
-
             //- Return start time index
             virtual label startTimeIndex() const;
 
@@ -514,7 +513,7 @@ public:
             virtual bool isAdjustTimeStep() const;
 
             //- Return the list of function objects
-            const functionObjectList& functionObjects() const
+            const functionObjectList& functionObjects() const noexcept
             {
                 return functionObjects_;
             }
@@ -644,13 +643,13 @@ public:
             virtual void endSubCycle();
 
             //- Return non-const access to the list of function objects
-            functionObjectList& functionObjects()
+            functionObjectList& functionObjects() noexcept
             {
                 return functionObjects_;
             }
 
 
-    // Member operators
+    // Member Operators
 
         //- Set deltaT to that specified and increment time via operator++()
         virtual Time& operator+=(const dimensionedScalar& deltaT);
diff --git a/src/OpenFOAM/db/Time/TimeIO.C b/src/OpenFOAM/db/Time/TimeIO.C
index aff2757899..55e4fc862b 100644
--- a/src/OpenFOAM/db/Time/TimeIO.C
+++ b/src/OpenFOAM/db/Time/TimeIO.C
@@ -335,20 +335,20 @@ void Foam::Time::readDict()
 
         if (formatName == "general")
         {
-            format_ = general;
+            format_ = fmtflags::general;
         }
         else if (formatName == "fixed")
         {
-            format_ = fixed;
+            format_ = fmtflags::fixed;
         }
         else if (formatName == "scientific")
         {
-            format_ = scientific;
+            format_ = fmtflags::scientific;
         }
         else
         {
             WarningInFunction
-                << "unsupported time format " << formatName
+                << "Unsupported time format " << formatName
                 << endl;
         }
     }
@@ -373,6 +373,7 @@ void Foam::Time::readDict()
         endTime_ = 0;
     }
 
+    // Adjust the TimeState name
     dimensionedScalar::name() = timeName(value());
 
     if (controlDict_.found("writeVersion"))
diff --git a/src/OpenFOAM/db/Time/TimeState.H b/src/OpenFOAM/db/Time/TimeState.H
index ec96dd934c..4bf3373d71 100644
--- a/src/OpenFOAM/db/Time/TimeState.H
+++ b/src/OpenFOAM/db/Time/TimeState.H
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2018-2021 OpenCFD Ltd.
+    Copyright (C) 2018-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -53,8 +53,19 @@ class TimeState
 :
     public dimensionedScalar
 {
+    // Private Member Functions
+
+        // //- Dimensions for 1/time
+        // inline static dimensionSet dimInvTime()
+        // {
+        //     return dimensionSet(0, 0, -1, 0, 0, 0, 0);
+        // }
+
+
 protected:
 
+    // Protected Data
+
         label timeIndex_;
         label writeTimeIndex_;
 
@@ -66,6 +77,22 @@ protected:
         bool writeTime_;
 
 
+    // Protected Member Functions
+
+        //- Reset some of TimeState (name, value, index)
+        void resetTimeState
+        (
+            const word& newName,
+            const scalar newValue,
+            const label newIndex
+        )
+        {
+            dimensionedScalar::name() = newName;
+            dimensionedScalar::value() = newValue;
+            timeIndex_ = newIndex;
+        }
+
+
 public:
 
     // Constructors
@@ -78,43 +105,50 @@ public:
     virtual ~TimeState() = default;
 
 
-    // Member functions
+    // Member Functions
 
-        // Access
+    // Conversion
 
-            //- Convert the user-time (e.g. CA deg) to real-time (s).
-            virtual scalar userTimeToTime(const scalar theta) const;
+        //- Convert the user-time (e.g. CA deg) to real-time (s).
+        virtual scalar userTimeToTime(const scalar theta) const;
 
-            //- Convert the real-time (s) into user-time (e.g. CA deg)
-            virtual scalar timeToUserTime(const scalar t) const;
-
-            //- Return current time value
-            inline scalar timeOutputValue() const;
-
-            //- Return current time index
-            inline label timeIndex() const noexcept;
-
-            //- Return time step value
-            inline scalar deltaTValue() const noexcept;
-
-            //- Return old time step value
-            inline scalar deltaT0Value() const noexcept;
-
-            //- Return time step
-            inline dimensionedScalar deltaT() const;
-
-            //- Return old time step
-            inline dimensionedScalar deltaT0() const;
+        //- Convert the real-time (s) into user-time (e.g. CA deg)
+        virtual scalar timeToUserTime(const scalar t) const;
 
 
-        // Check
+    // Access
 
-            //- True if this is a write time
-            inline bool writeTime() const noexcept;
+        //- Return the current user-time value.
+        //- (ie, after applying any timeToUserTime() conversion)
+        inline scalar timeOutputValue() const;
 
-            //- Deprecated(2016-05) return true if this is a write time.
-            //  \deprecated(2016-05) - use writeTime() method
-            bool outputTime() const noexcept { return this->writeTime(); }
+        //- Return the current time name
+        inline const word& timeName() const noexcept;
+
+        //- Return the current time index
+        inline label timeIndex() const noexcept;
+
+        //- Return time step value
+        inline scalar deltaTValue() const noexcept;
+
+        //- Return old time step value
+        inline scalar deltaT0Value() const noexcept;
+
+        //- Return time step
+        inline dimensionedScalar deltaT() const;
+
+        //- Return old time step
+        inline dimensionedScalar deltaT0() const;
+
+        //- True if this is a write interval
+        inline bool writeTime() const noexcept;
+
+
+    // Housekeeping
+
+        //- Deprecated(2016-05) return true if this is a write time.
+        //  \deprecated(2016-05) - use writeTime() method
+        bool outputTime() const noexcept { return this->writeTime(); }
 };
 
 
diff --git a/src/OpenFOAM/db/Time/TimeStateI.H b/src/OpenFOAM/db/Time/TimeStateI.H
index bf9dd0f5c4..287d3c60a8 100644
--- a/src/OpenFOAM/db/Time/TimeStateI.H
+++ b/src/OpenFOAM/db/Time/TimeStateI.H
@@ -30,10 +30,23 @@ License
 
 inline Foam::scalar Foam::TimeState::timeOutputValue() const
 {
-    return timeToUserTime(value());
+    return timeToUserTime(dimensionedScalar::value());
 }
 
 
+inline const Foam::word& Foam::TimeState::timeName() const noexcept
+{
+    return dimensionedScalar::name();
+}
+
+
+// FUTURE?
+// inline Foam::scalar Foam::TimeState::timeValue() const noexcept
+// {
+//     return dimensionedScalar::value();
+// }
+
+
 inline Foam::label Foam::TimeState::timeIndex() const noexcept
 {
     return timeIndex_;
diff --git a/src/OpenFOAM/expressions/exprDriver/exprDriver.C b/src/OpenFOAM/expressions/exprDriver/exprDriver.C
index 6ca0715be9..f8afebea5e 100644
--- a/src/OpenFOAM/expressions/exprDriver/exprDriver.C
+++ b/src/OpenFOAM/expressions/exprDriver/exprDriver.C
@@ -283,11 +283,11 @@ Foam::scalar Foam::expressions::exprDriver::deltaT() const
 {
     if (timeStatePtr_)
     {
-        return timeStatePtr_->deltaT().value();
+        return timeStatePtr_->deltaTValue();
     }
     else if (obrPtr_)
     {
-        return obrPtr_->time().deltaT().value();
+        return obrPtr_->time().deltaTValue();
     }
     return 0;
 }
diff --git a/src/dynamicFaMesh/interfaceTrackingFvMesh/functionObjects/writeFreeSurface/writeFreeSurface.C b/src/dynamicFaMesh/interfaceTrackingFvMesh/functionObjects/writeFreeSurface/writeFreeSurface.C
index 2ca76be4fa..70e56a95d1 100644
--- a/src/dynamicFaMesh/interfaceTrackingFvMesh/functionObjects/writeFreeSurface/writeFreeSurface.C
+++ b/src/dynamicFaMesh/interfaceTrackingFvMesh/functionObjects/writeFreeSurface/writeFreeSurface.C
@@ -48,7 +48,7 @@ namespace Foam
 
 bool Foam::writeFreeSurface::writeData()
 {
-    if (time_.outputTime())
+    if (time_.writeTime())
     {
         const fvMesh& mesh =
             time_.lookupObject<fvMesh>(polyMesh::defaultRegion);
diff --git a/src/dynamicFaMesh/interfaceTrackingFvMesh/interfaceTrackingFvMesh.C b/src/dynamicFaMesh/interfaceTrackingFvMesh/interfaceTrackingFvMesh.C
index d3c87b6f33..ef431b1d9e 100644
--- a/src/dynamicFaMesh/interfaceTrackingFvMesh/interfaceTrackingFvMesh.C
+++ b/src/dynamicFaMesh/interfaceTrackingFvMesh/interfaceTrackingFvMesh.C
@@ -834,8 +834,7 @@ void Foam::interfaceTrackingFvMesh::smoothFreeSurfaceMesh()
             )
         );
 
-    fsPatchPointMeshU ==
-        displacement/mesh().time().deltaT().value();
+    fsPatchPointMeshU == displacement/mesh().time().deltaTValue();
 
     dynamicMotionSolverFvMesh::update();
 }
@@ -1008,7 +1007,7 @@ Foam::scalar Foam::interfaceTrackingFvMesh::maxCourantNumber()
 
         CoNum = gMax
         (
-            mesh().time().deltaT().value()/
+            mesh().time().deltaTValue()/
             sqrt
             (
                 Foam::pow(dE, 3.0)/2.0/M_PI/(sigma().value() + SMALL)
@@ -1027,7 +1026,7 @@ Foam::scalar Foam::interfaceTrackingFvMesh::maxCourantNumber()
 
         CoNum = gMax
         (
-            mesh().time().deltaT().value()/
+            mesh().time().deltaTValue()/
             sqrt
             (
                 Foam::pow(dE, 3.0)/2.0/M_PI/sigmaE
@@ -2125,7 +2124,7 @@ bool Foam::interfaceTrackingFvMesh::update()
          == fv::CrankNicolsonDdtScheme<vector>::typeName
         )
         {
-            sweptVolCorr *= (1.0/2.0)*mesh().time().deltaT().value();
+            sweptVolCorr *= (1.0/2.0)*mesh().time().deltaTValue();
         }
         else if
         (
@@ -2133,7 +2132,7 @@ bool Foam::interfaceTrackingFvMesh::update()
          == fv::EulerDdtScheme<vector>::typeName
         )
         {
-            sweptVolCorr *= mesh().time().deltaT().value();
+            sweptVolCorr *= mesh().time().deltaTValue();
         }
         else if
         (
@@ -2143,11 +2142,11 @@ bool Foam::interfaceTrackingFvMesh::update()
         {
             if (mesh().time().timeIndex() == 1)
             {
-                sweptVolCorr *= mesh().time().deltaT().value();
+                sweptVolCorr *= mesh().time().deltaTValue();
             }
             else
             {
-                sweptVolCorr *= (2.0/3.0)*mesh().time().deltaT().value();
+                sweptVolCorr *= (2.0/3.0)*mesh().time().deltaTValue();
             }
         }
         else
@@ -2212,8 +2211,7 @@ bool Foam::interfaceTrackingFvMesh::update()
                 )
             );
 
-        fsPatchPointMeshU ==
-            displacement/mesh().time().deltaT().value();
+        fsPatchPointMeshU == displacement/mesh().time().deltaTValue();
 
         dynamicMotionSolverFvMesh::update();
 
@@ -2245,8 +2243,7 @@ bool Foam::interfaceTrackingFvMesh::update()
                 )
             );
 
-        fsPatchPointMeshU ==
-            displacement/mesh().time().deltaT().value();
+        fsPatchPointMeshU == displacement/mesh().time().deltaTValue();
 
         dynamicMotionSolverFvMesh::update();
     }
diff --git a/src/faOptions/sources/derived/jouleHeatingSource/jouleHeatingSource.C b/src/faOptions/sources/derived/jouleHeatingSource/jouleHeatingSource.C
index b50853bccc..0de1a2276e 100644
--- a/src/faOptions/sources/derived/jouleHeatingSource/jouleHeatingSource.C
+++ b/src/faOptions/sources/derived/jouleHeatingSource/jouleHeatingSource.C
@@ -143,7 +143,7 @@ void Foam::fa::jouleHeatingSource::addSup
         // Add the Joule heating contribution
         areaVectorField gradV("gradV", fac::grad(V_));
 
-        if (debug > 1 && mesh().time().outputTime())
+        if (debug > 1 && mesh().time().writeTime())
         {
             areaScalarField qgradV("gradVSource", (gradV & gradV));
             qgradV.write();
diff --git a/src/finiteArea/finiteArea/d2dt2Schemes/EulerFaD2dt2Scheme/EulerFaD2dt2Scheme.C b/src/finiteArea/finiteArea/d2dt2Schemes/EulerFaD2dt2Scheme/EulerFaD2dt2Scheme.C
index 53eadce916..7327de14f5 100644
--- a/src/finiteArea/finiteArea/d2dt2Schemes/EulerFaD2dt2Scheme/EulerFaD2dt2Scheme.C
+++ b/src/finiteArea/finiteArea/d2dt2Schemes/EulerFaD2dt2Scheme/EulerFaD2dt2Scheme.C
@@ -44,14 +44,14 @@ namespace fa
 template<class Type>
 scalar EulerFaD2dt2Scheme<Type>::deltaT_() const
 {
-    return mesh().time().deltaT().value();
+    return mesh().time().deltaTValue();
 }
 
 
 template<class Type>
 scalar EulerFaD2dt2Scheme<Type>::deltaT0_() const
 {
-    return mesh().time().deltaT0().value();
+    return mesh().time().deltaT0Value();
 }
 
 
diff --git a/src/finiteArea/finiteArea/ddtSchemes/EulerFaDdtScheme/EulerFaDdtScheme.C b/src/finiteArea/finiteArea/ddtSchemes/EulerFaDdtScheme/EulerFaDdtScheme.C
index e557edfc56..8b9c8e9fac 100644
--- a/src/finiteArea/finiteArea/ddtSchemes/EulerFaDdtScheme/EulerFaDdtScheme.C
+++ b/src/finiteArea/finiteArea/ddtSchemes/EulerFaDdtScheme/EulerFaDdtScheme.C
@@ -456,7 +456,7 @@ EulerFaDdtScheme<Type>::famDdt
 
     faMatrix<Type>& fam = tfam.ref();
 
-    scalar rDeltaT = 1.0/mesh().time().deltaT().value();
+    scalar rDeltaT = 1.0/mesh().time().deltaTValue();
 
     fam.diag() = rDeltaT*mesh().S();
 
@@ -491,7 +491,7 @@ EulerFaDdtScheme<Type>::famDdt
     );
     faMatrix<Type>& fam = tfam.ref();
 
-    scalar rDeltaT = 1.0/mesh().time().deltaT().value();
+    scalar rDeltaT = 1.0/mesh().time().deltaTValue();
 
     fam.diag() = rDeltaT*rho.value()*mesh().S();
 
@@ -528,7 +528,7 @@ EulerFaDdtScheme<Type>::famDdt
     );
     faMatrix<Type>& fam = tfam.ref();
 
-    scalar rDeltaT = 1.0/mesh().time().deltaT().value();
+    scalar rDeltaT = 1.0/mesh().time().deltaTValue();
 
     fam.diag() = rDeltaT*rho.primitiveField()*mesh().S();
 
diff --git a/src/finiteArea/finiteArea/ddtSchemes/backwardFaDdtScheme/backwardFaDdtScheme.C b/src/finiteArea/finiteArea/ddtSchemes/backwardFaDdtScheme/backwardFaDdtScheme.C
index 81a0178e61..01c0576d71 100644
--- a/src/finiteArea/finiteArea/ddtSchemes/backwardFaDdtScheme/backwardFaDdtScheme.C
+++ b/src/finiteArea/finiteArea/ddtSchemes/backwardFaDdtScheme/backwardFaDdtScheme.C
@@ -44,14 +44,14 @@ namespace fa
 template<class Type>
 scalar backwardFaDdtScheme<Type>::deltaT_() const
 {
-    return mesh().time().deltaT().value();
+    return mesh().time().deltaTValue();
 }
 
 
 template<class Type>
 scalar backwardFaDdtScheme<Type>::deltaT0_() const
 {
-    return mesh().time().deltaT0().value();
+    return mesh().time().deltaT0Value();
 }
 
 
@@ -65,7 +65,7 @@ scalar backwardFaDdtScheme<Type>::deltaT0_(const GeoField& vf) const
     }
     else
     {
-        return deltaT0_();
+        return mesh().time().deltaT0Value();
     }
 }
 
diff --git a/src/finiteArea/finiteArea/ddtSchemes/boundedBackwardFaDdtScheme/boundedBackwardFaDdtScheme.C b/src/finiteArea/finiteArea/ddtSchemes/boundedBackwardFaDdtScheme/boundedBackwardFaDdtScheme.C
index 73b342d5df..b63446ae20 100644
--- a/src/finiteArea/finiteArea/ddtSchemes/boundedBackwardFaDdtScheme/boundedBackwardFaDdtScheme.C
+++ b/src/finiteArea/finiteArea/ddtSchemes/boundedBackwardFaDdtScheme/boundedBackwardFaDdtScheme.C
@@ -43,13 +43,13 @@ namespace fa
 
 scalar boundedBackwardFaDdtScheme::deltaT_() const
 {
-    return mesh().time().deltaT().value();
+    return mesh().time().deltaTValue();
 }
 
 
 scalar boundedBackwardFaDdtScheme::deltaT0_() const
 {
-    return mesh().time().deltaT0().value();
+    return mesh().time().deltaT0Value();
 }
 
 
diff --git a/src/finiteVolume/expressions/base/fvExprDriverIO.C b/src/finiteVolume/expressions/base/fvExprDriverIO.C
index 500ac1c772..69badfa7a6 100644
--- a/src/finiteVolume/expressions/base/fvExprDriverIO.C
+++ b/src/finiteVolume/expressions/base/fvExprDriverIO.C
@@ -279,7 +279,7 @@ void Foam::expressions::fvExprDriver::createWriterAndRead(const word& name)
 
 void Foam::expressions::fvExprDriver::tryWrite() const
 {
-    if (writer_ && mesh().time().outputTime())
+    if (writer_ && mesh().time().writeTime())
     {
         writer_->write();
     }
diff --git a/src/finiteVolume/fields/fvPatchFields/derived/activePressureForceBaffleVelocity/activePressureForceBaffleVelocityFvPatchVectorField.C b/src/finiteVolume/fields/fvPatchFields/derived/activePressureForceBaffleVelocity/activePressureForceBaffleVelocityFvPatchVectorField.C
index 983e4f83c0..6f2a989768 100644
--- a/src/finiteVolume/fields/fvPatchFields/derived/activePressureForceBaffleVelocity/activePressureForceBaffleVelocityFvPatchVectorField.C
+++ b/src/finiteVolume/fields/fvPatchFields/derived/activePressureForceBaffleVelocity/activePressureForceBaffleVelocityFvPatchVectorField.C
@@ -303,7 +303,7 @@ void Foam::activePressureForceBaffleVelocityFvPatchVectorField::updateCoeffs()
                 openFraction_
               + min
                 (
-                    this->db().time().deltaT().value()/openingTime_,
+                    this->db().time().deltaTValue()/openingTime_,
                     maxOpenFractionDelta_
                 )
             );
diff --git a/src/functionObjects/doc/functionObjects.dox b/src/functionObjects/doc/functionObjects.dox
index fc4c772bef..f2da136c61 100644
--- a/src/functionObjects/doc/functionObjects.dox
+++ b/src/functionObjects/doc/functionObjects.dox
@@ -68,7 +68,7 @@ functions
         timeEnd             10;
         evaluateControl     timeStep;
         evaluateInterval    1;
-        writeControl        outputTime;
+        writeControl        writeTime;
         writeInterval       1;
         ...
     }
diff --git a/src/functionObjects/field/DMD/DMDModels/derived/STDMD/STDMD.C b/src/functionObjects/field/DMD/DMDModels/derived/STDMD/STDMD.C
index b733b036d8..3678b341e5 100644
--- a/src/functionObjects/field/DMD/DMDModels/derived/STDMD/STDMD.C
+++ b/src/functionObjects/field/DMD/DMDModels/derived/STDMD/STDMD.C
@@ -887,7 +887,7 @@ bool Foam::DMDModels::STDMD::read(const dictionary& dict)
             "interval",
             (
                 dict.getCheck<label>("executeInterval", labelMinMax::ge(1))
-               *mesh_.time().deltaT().value()
+               *mesh_.time().deltaTValue()
             ),
             scalarMinMax::ge(0)
         );
diff --git a/src/functionObjects/field/reactionSensitivityAnalysis/reactionsSensitivityAnalysis.C b/src/functionObjects/field/reactionSensitivityAnalysis/reactionsSensitivityAnalysis.C
index 73dff8766f..a0bc517f95 100644
--- a/src/functionObjects/field/reactionSensitivityAnalysis/reactionsSensitivityAnalysis.C
+++ b/src/functionObjects/field/reactionSensitivityAnalysis/reactionsSensitivityAnalysis.C
@@ -95,7 +95,7 @@ calculateSpeciesRR
     );
     auto& RR = RRt.ref();
 
-    scalar dt = time_.deltaT().value();
+    scalar dt = time_.deltaTValue();
 
     endTime_ += dt;
 
@@ -131,9 +131,9 @@ writeSpeciesRR()
 {
 
     consFilePtr_() << "time : " << mesh_.time().value() << tab << nl;
-    consFilePtr_() << "delta T : "<< mesh_.time().deltaT().value() << nl << nl;
+    consFilePtr_() << "delta T : "<< mesh_.time().deltaTValue() << nl << nl;
     prodFilePtr_() << "time : " << mesh_.time().value() << tab << nl;
-    prodFilePtr_() << "delta T : "<< mesh_.time().deltaT().value() << nl << nl;
+    prodFilePtr_() << "delta T : "<< mesh_.time().deltaTValue() << nl << nl;
 
     consIntFilePtr_() << "start time : " << startTime_ << tab
         << "end time :" <<  endTime_ << nl;
diff --git a/src/functionObjects/phaseSystems/sizeDistribution/sizeDistribution.H b/src/functionObjects/phaseSystems/sizeDistribution/sizeDistribution.H
index ca21b6a64a..ce8a1bd2cc 100644
--- a/src/functionObjects/phaseSystems/sizeDistribution/sizeDistribution.H
+++ b/src/functionObjects/phaseSystems/sizeDistribution/sizeDistribution.H
@@ -39,7 +39,7 @@ Description
     {
         type sizeDistribution;
         libs (reactingEulerFoamFunctionObjects);
-        writeControl    outputTime;
+        writeControl    writeTime;
         writeInterval   1;
         log             true;
         ...
diff --git a/src/functionObjects/solvers/energyTransport/energyTransport.H b/src/functionObjects/solvers/energyTransport/energyTransport.H
index 5376401cff..aa3b9929f0 100644
--- a/src/functionObjects/solvers/energyTransport/energyTransport.H
+++ b/src/functionObjects/solvers/energyTransport/energyTransport.H
@@ -53,7 +53,7 @@ Usage
             libs            (energyTransportFunctionObjects);
 
             enabled         true;
-            writeControl    outputTime;
+            writeControl    writeTime;
             writeInterval   1;
 
             field           T;
@@ -99,7 +99,7 @@ Usage
             libs            (energyTransportFunctionObjects);
 
             enabled         true;
-            writeControl    outputTime;
+            writeControl    writeTime;
             writeInterval   1;
 
             field           T;
diff --git a/src/functionObjects/solvers/scalarTransport/scalarTransport.H b/src/functionObjects/solvers/scalarTransport/scalarTransport.H
index 25593a5ca2..686d6cdba6 100644
--- a/src/functionObjects/solvers/scalarTransport/scalarTransport.H
+++ b/src/functionObjects/solvers/scalarTransport/scalarTransport.H
@@ -84,7 +84,7 @@ Usage
             libs            (solverFunctionObjects);
 
             enabled         true;
-            writeControl    outputTime;
+            writeControl    writeTime;
             writeInterval   1;
 
             field           s;
diff --git a/src/functionObjects/utilities/areaWrite/areaWrite.H b/src/functionObjects/utilities/areaWrite/areaWrite.H
index bca7c2a36d..197857ee96 100644
--- a/src/functionObjects/utilities/areaWrite/areaWrite.H
+++ b/src/functionObjects/utilities/areaWrite/areaWrite.H
@@ -38,7 +38,7 @@ Description
         libs    (utilityFunctionObjects);
 
         // Write at same frequency as fields
-        writeControl    outputTime;
+        writeControl    writeTime;
         writeInterval   1;
 
         // Fields to be sampled
diff --git a/src/optimisation/adjointOptimisation/adjoint/objectives/objective/objective.C b/src/optimisation/adjointOptimisation/adjoint/objectives/objective/objective.C
index ddd759300f..76c4fb4e3a 100644
--- a/src/optimisation/adjointOptimisation/adjoint/objectives/objective/objective.C
+++ b/src/optimisation/adjointOptimisation/adjoint/objectives/objective/objective.C
@@ -306,7 +306,7 @@ void objective::accumulateJMean()
         const scalar time = mesh_.time().value();
         if (isWithinIntegrationTime())
         {
-            const scalar dt = mesh_.time().deltaT().value();
+            const scalar dt = mesh_.time().deltaTValue();
             const scalar elapsedTime = time - integrationStartTimePtr_();
             const scalar denom = elapsedTime + dt;
             JMean_ = (JMean_*elapsedTime + J_*dt)/denom;
diff --git a/src/overset/cellCellStencil/cellCellStencil/cellCellStencil.C b/src/overset/cellCellStencil/cellCellStencil/cellCellStencil.C
index 37395777ed..60286a7bb3 100644
--- a/src/overset/cellCellStencil/cellCellStencil/cellCellStencil.C
+++ b/src/overset/cellCellStencil/cellCellStencil/cellCellStencil.C
@@ -505,7 +505,7 @@ void Foam::cellCellStencil::walkFront
         }
 
 
-        if ((debug&2) && (mesh_.time().outputTime()))
+        if ((debug & 2) && mesh_.time().writeTime())
         {
             tmp<volScalarField> tfld
             (
@@ -656,7 +656,7 @@ void Foam::cellCellStencil::walkFront
             fraction.transfer(newFraction);
         }
 
-        if ((debug&2) && (mesh_.time().outputTime()))
+        if ((debug & 2) && mesh_.time().writeTime())
         {
             tmp<volScalarField> tfld
             (
@@ -708,7 +708,7 @@ void Foam::cellCellStencil::walkFront
     }
 
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
diff --git a/src/overset/cellCellStencil/cellVolumeWeight/cellVolumeWeightCellCellStencil.C b/src/overset/cellCellStencil/cellVolumeWeight/cellVolumeWeightCellCellStencil.C
index a9f238d1c0..437330112a 100644
--- a/src/overset/cellCellStencil/cellVolumeWeight/cellVolumeWeightCellCellStencil.C
+++ b/src/overset/cellCellStencil/cellVolumeWeight/cellVolumeWeightCellCellStencil.C
@@ -657,7 +657,7 @@ bool Foam::cellCellStencils::cellVolumeWeight::update()
         markPatchCells(partMesh, partCellMap, allPatchTypes);
     }
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -794,7 +794,7 @@ bool Foam::cellCellStencils::cellVolumeWeight::update()
     }
 
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -840,7 +840,7 @@ bool Foam::cellCellStencils::cellVolumeWeight::update()
     }
 
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -864,7 +864,7 @@ bool Foam::cellCellStencils::cellVolumeWeight::update()
     // Mark unreachable bits
     findHoles(globalCells, mesh_, zoneID, allStencil, allCellTypes);
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -910,7 +910,7 @@ bool Foam::cellCellStencils::cellVolumeWeight::update()
     );
 
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -1024,16 +1024,13 @@ bool Foam::cellCellStencils::cellVolumeWeight::update()
     }
 
     // Write to volField for debugging
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
-        if ((debug&2) && (mesh_.time().outputTime()))
-        {
-            tmp<volScalarField> tfld
-            (
-                createField(mesh_, "allCellTypes_final", allCellTypes)
-            );
-            tfld().write();
-        }
+        tmp<volScalarField> tfld
+        (
+            createField(mesh_, "allCellTypes_final", allCellTypes)
+        );
+        tfld().write();
     }
 
 
@@ -1066,7 +1063,7 @@ bool Foam::cellCellStencils::cellVolumeWeight::update()
     );
 
     // Dump interpolation stencil
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         // Dump weight
         cellInterpolationWeight_.instance() = mesh_.time().timeName();
diff --git a/src/overset/cellCellStencil/inverseDistance/inverseDistanceCellCellStencil.C b/src/overset/cellCellStencil/inverseDistance/inverseDistanceCellCellStencil.C
index 530b5ac215..17b92e868d 100644
--- a/src/overset/cellCellStencil/inverseDistance/inverseDistanceCellCellStencil.C
+++ b/src/overset/cellCellStencil/inverseDistance/inverseDistanceCellCellStencil.C
@@ -1478,7 +1478,7 @@ void Foam::cellCellStencils::inverseDistance::holeExtrapolationStencil
             }
         }
 
-        if (debug&2)
+        if (debug & 2)
         {
             reduce(nSpecialNear, sumOp<label>());
             reduce(nSpecialFar, sumOp<label>());
@@ -2051,7 +2051,7 @@ bool Foam::cellCellStencils::inverseDistance::update()
         }
     }
 
-    if ((debug&2)&& (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -2089,7 +2089,7 @@ bool Foam::cellCellStencils::inverseDistance::update()
         }
     }
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -2108,7 +2108,7 @@ bool Foam::cellCellStencils::inverseDistance::update()
     findHoles(globalCells, mesh_, zoneID, allStencil, allCellTypes);
 
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -2116,7 +2116,7 @@ bool Foam::cellCellStencils::inverseDistance::update()
         );
         tfld().write();
     }
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         labelList stencilSize(mesh_.nCells());
         forAll(allStencil, celli)
@@ -2172,7 +2172,7 @@ bool Foam::cellCellStencils::inverseDistance::update()
 //         }
 //     }
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -2216,7 +2216,7 @@ bool Foam::cellCellStencils::inverseDistance::update()
         useLayer
     );
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -2365,7 +2365,7 @@ bool Foam::cellCellStencils::inverseDistance::update()
     >(cellInterpolationWeight_.boundaryFieldRef(), false);
 
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         // Dump mesh
         mesh_.time().write();
@@ -2404,9 +2404,8 @@ bool Foam::cellCellStencils::inverseDistance::update()
         holeExtrapolationStencil(globalCells);
     }
 
-    if ((debug&2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
-
         // Dump weight
         cellInterpolationWeight_.instance() = mesh_.time().timeName();
         cellInterpolationWeight_.write();
diff --git a/src/overset/cellCellStencil/trackingInverseDistance/trackingInverseDistanceCellCellStencil.C b/src/overset/cellCellStencil/trackingInverseDistance/trackingInverseDistanceCellCellStencil.C
index 1917e31b8d..8c22dc50fb 100644
--- a/src/overset/cellCellStencil/trackingInverseDistance/trackingInverseDistanceCellCellStencil.C
+++ b/src/overset/cellCellStencil/trackingInverseDistance/trackingInverseDistanceCellCellStencil.C
@@ -834,7 +834,7 @@ bool Foam::cellCellStencils::trackingInverseDistance::update()
     DebugInfo<< FUNCTION_NAME << " : Determined holes and donor-acceptors"
         << endl;
 
-    if ((debug & 2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -875,7 +875,7 @@ bool Foam::cellCellStencils::trackingInverseDistance::update()
     }
     DebugInfo<< FUNCTION_NAME << " : Removed bad donors" << endl;
 
-    if ((debug & 2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -894,7 +894,7 @@ bool Foam::cellCellStencils::trackingInverseDistance::update()
     findHoles(globalCells_, mesh_, zoneID, allStencil, allCellTypes);
     DebugInfo<< FUNCTION_NAME << " : Flood-filled holes" << endl;
 
-    if ((debug & 2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -947,7 +947,7 @@ bool Foam::cellCellStencils::trackingInverseDistance::update()
         dict_.getOrDefault("useLayer", -1)
     );
 
-    if ((debug & 2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         tmp<volScalarField> tfld
         (
@@ -1063,7 +1063,7 @@ bool Foam::cellCellStencils::trackingInverseDistance::update()
     >(cellInterpolationWeight_.boundaryFieldRef(), false);
 
 
-    if ((debug & 2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         // Dump mesh
         mesh_.time().write();
@@ -1106,7 +1106,7 @@ bool Foam::cellCellStencils::trackingInverseDistance::update()
     }
 
 
-    if ((debug & 2) && (mesh_.time().outputTime()))
+    if ((debug & 2) && mesh_.time().writeTime())
     {
         // Dump weight
         cellInterpolationWeight_.instance() = mesh_.time().timeName();
diff --git a/src/overset/oversetFvMesh/oversetFvMeshBaseTemplates.C b/src/overset/oversetFvMesh/oversetFvMeshBaseTemplates.C
index faa741cafe..c57a635818 100644
--- a/src/overset/oversetFvMesh/oversetFvMeshBaseTemplates.C
+++ b/src/overset/oversetFvMesh/oversetFvMeshBaseTemplates.C
@@ -744,7 +744,7 @@ Foam::SolverPerformance<Type> Foam::oversetFvMeshBase::solveOverset
     // Calculate stabilised diagonal as normalisation for interpolation
     const scalarField norm(normalisation(m));
 
-    if (debug && mesh_.time().outputTime())
+    if (debug && mesh_.time().writeTime())
     {
         volScalarField scale
         (
diff --git a/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C b/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C
index 6943f0d90a..c8142628ac 100644
--- a/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C
+++ b/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C
@@ -119,7 +119,7 @@ void Foam::multiphaseSystem::solveAlphas()
 
         MULES::limit
         (
-            1.0/mesh_.time().deltaT().value(),
+            1.0/mesh_.time().deltaTValue(),
             geometricOneField(),
             phase,
             phi_,
diff --git a/src/phaseSystemModels/multiphaseInter/phasesSystem/interfaceModels/porousModels/VollerPrakash/VollerPrakash.C b/src/phaseSystemModels/multiphaseInter/phasesSystem/interfaceModels/porousModels/VollerPrakash/VollerPrakash.C
index 2771f3bc0c..cb6067bf18 100644
--- a/src/phaseSystemModels/multiphaseInter/phasesSystem/interfaceModels/porousModels/VollerPrakash/VollerPrakash.C
+++ b/src/phaseSystemModels/multiphaseInter/phasesSystem/interfaceModels/porousModels/VollerPrakash/VollerPrakash.C
@@ -68,7 +68,7 @@ Foam::porousModels::VollerPrakash::S() const
     const volScalarField& solidAlpha =
         mesh_.lookupObject<volScalarField>(solidPhase_);
 
-    if (mesh_.time().outputTime() && debug)
+    if (debug && mesh_.time().writeTime())
     {
         volScalarField Su
         (
diff --git a/src/phaseSystemModels/multiphaseInter/phasesSystem/massTransferModels/diffusionGasEvaporation/diffusionGasEvaporation.C b/src/phaseSystemModels/multiphaseInter/phasesSystem/massTransferModels/diffusionGasEvaporation/diffusionGasEvaporation.C
index 18ea28da4d..6a7e10ec02 100644
--- a/src/phaseSystemModels/multiphaseInter/phasesSystem/massTransferModels/diffusionGasEvaporation/diffusionGasEvaporation.C
+++ b/src/phaseSystemModels/multiphaseInter/phasesSystem/massTransferModels/diffusionGasEvaporation/diffusionGasEvaporation.C
@@ -198,7 +198,7 @@ Foam::meltingEvaporationModels::diffusionGasEvaporation<Thermo, OtherThermo>
        *C_*rhog*Dvg*gradYgm*interfaceArea_
        /(1 - YvSat);
 
-    if (debug && mesh.time().outputTime())
+    if (debug && mesh.time().writeTime())
     {
         volScalarField pSat("pSat", saturationModelPtr_->pSat(T));
         pSat.write();
diff --git a/src/phaseSystemModels/multiphaseInter/phasesSystem/multiphaseSystem/multiphaseSystem.C b/src/phaseSystemModels/multiphaseInter/phasesSystem/multiphaseSystem/multiphaseSystem.C
index 7758370b7f..4cf91a30e3 100644
--- a/src/phaseSystemModels/multiphaseInter/phasesSystem/multiphaseSystem/multiphaseSystem.C
+++ b/src/phaseSystemModels/multiphaseInter/phasesSystem/multiphaseSystem/multiphaseSystem.C
@@ -305,7 +305,7 @@ void Foam::multiphaseInter::multiphaseSystem::solveAlphas()
 
             MULES::limit
             (
-                1.0/mesh_.time().deltaT().value(),
+                1.0/mesh_.time().deltaTValue(),
                 geometricOneField(),
                 alpha1,
                 phi,
@@ -479,7 +479,7 @@ Foam::multiphaseInter::multiphaseSystem::maxDiffNo() const
         maxVal = max(maxVal, max(iter()->diffNo()).value());
     }
 
-    return maxVal * mesh_.time().deltaT().value();
+    return maxVal * mesh_.time().deltaTValue();
 }
 
 
diff --git a/src/phaseSystemModels/multiphaseInter/phasesSystem/phaseModel/MultiComponentPhaseModel/MultiComponentPhaseModel.C b/src/phaseSystemModels/multiphaseInter/phasesSystem/phaseModel/MultiComponentPhaseModel/MultiComponentPhaseModel.C
index 1dca7f055c..3fd085f7e8 100644
--- a/src/phaseSystemModels/multiphaseInter/phasesSystem/phaseModel/MultiComponentPhaseModel/MultiComponentPhaseModel.C
+++ b/src/phaseSystemModels/multiphaseInter/phasesSystem/phaseModel/MultiComponentPhaseModel/MultiComponentPhaseModel.C
@@ -324,7 +324,7 @@ void Foam::MultiComponentPhaseModel<BasePhaseModel, phaseThermo>::solveYi
 
             MULES::limit
             (
-                1.0/mesh.time().deltaT().value(),
+                1.0/mesh.time().deltaTValue(),
                 geometricOneField(),
                 Yi,
                 phi,
diff --git a/src/regionFaModels/liquidFilm/liquidFilmBase.C b/src/regionFaModels/liquidFilm/liquidFilmBase.C
index a10af1c3a8..e7143a516d 100644
--- a/src/regionFaModels/liquidFilm/liquidFilmBase.C
+++ b/src/regionFaModels/liquidFilm/liquidFilmBase.C
@@ -261,7 +261,7 @@ scalar liquidFilmBase::CourantNumber() const
     );
 
     CoNum =
-        max(SfUfbyDelta/regionMesh().magLe()).value()*time().deltaT().value();
+        max(SfUfbyDelta/regionMesh().magLe()).value()*time().deltaTValue();
 
     velMag = max(mag(phif_)/regionMesh().magLe()).value();
 
diff --git a/src/sampling/probes/probes.H b/src/sampling/probes/probes.H
index 542e7455a8..7e9e54e68f 100644
--- a/src/sampling/probes/probes.H
+++ b/src/sampling/probes/probes.H
@@ -46,7 +46,7 @@ Description
         name            probes;
 
         // Write at same frequency as fields
-        writeControl    outputTime;
+        writeControl    writeTime;
         writeInterval   1;
 
         // Fields to be probed
diff --git a/src/sampling/sampledSurface/sampledSurfaces/sampledSurfaces.H b/src/sampling/sampledSurface/sampledSurfaces/sampledSurfaces.H
index ec0ff59faa..45d25bcd87 100644
--- a/src/sampling/sampledSurface/sampledSurfaces/sampledSurfaces.H
+++ b/src/sampling/sampledSurface/sampledSurfaces/sampledSurfaces.H
@@ -41,7 +41,7 @@ Description
         libs    (sampling);
 
         // Write at same frequency as fields
-        writeControl    outputTime;
+        writeControl    writeTime;
         writeInterval   1;
 
         // Fields to be sampled
diff --git a/src/topoChangerFvMesh/movingConeTopoFvMesh/movingConeTopoFvMesh.C b/src/topoChangerFvMesh/movingConeTopoFvMesh/movingConeTopoFvMesh.C
index 14115509ab..51221b8fad 100644
--- a/src/topoChangerFvMesh/movingConeTopoFvMesh/movingConeTopoFvMesh.C
+++ b/src/topoChangerFvMesh/movingConeTopoFvMesh/movingConeTopoFvMesh.C
@@ -366,7 +366,7 @@ bool Foam::movingConeTopoFvMesh::update()
                 topoChangeMap().preMotionPoints()
               + (
                     pos0(0.5 - mag(motionMask_)) // cells above the body
-                )*curMotionVel_*time().deltaT().value();
+                )*curMotionVel_*time().deltaTValue();
         }
         else
         {
@@ -385,7 +385,7 @@ bool Foam::movingConeTopoFvMesh::update()
                 points()
               + (
                     pos0(0.5 - mag(motionMask_)) // cells above the body
-                )*curMotionVel_*time().deltaT().value();
+                )*curMotionVel_*time().deltaTValue();
         }
     }
     else
@@ -396,7 +396,7 @@ bool Foam::movingConeTopoFvMesh::update()
             points()
           + (
                 pos0(0.5 - mag(motionMask_)) // cells above the body
-           )*curMotionVel_*time().deltaT().value();
+           )*curMotionVel_*time().deltaTValue();
     }
 
     // The mesh now contains the cells with zero volume
diff --git a/src/transportModels/geometricVoF/advectionSchemes/isoAdvection/isoAdvectionTemplates.C b/src/transportModels/geometricVoF/advectionSchemes/isoAdvection/isoAdvectionTemplates.C
index e51b4c9246..c79592c3b4 100644
--- a/src/transportModels/geometricVoF/advectionSchemes/isoAdvection/isoAdvectionTemplates.C
+++ b/src/transportModels/geometricVoF/advectionSchemes/isoAdvection/isoAdvectionTemplates.C
@@ -234,7 +234,7 @@ void Foam::isoAdvection::boundFlux
 {
     addProfilingInFunction(geometricVoF);
     DebugInFunction << endl;
-    scalar rDeltaT = 1/mesh_.time().deltaTValue();
+    const scalar rDeltaT = 1.0/mesh_.time().deltaTValue();
 
     correctedFaces.clear();
     const scalar aTol = 100*SMALL; // Note: tolerances
@@ -400,7 +400,7 @@ void Foam::isoAdvection::advect(const SpType& Sp, const SuType& Su)
 
     scalar advectionStartTime = mesh_.time().elapsedCpuTime();
 
-    const scalar rDeltaT = 1/mesh_.time().deltaTValue();
+    const scalar rDeltaT = 1.0/mesh_.time().deltaTValue();
 
     // reconstruct the interface
     surf_->reconstruct();
diff --git a/tutorials/incompressible/pimpleFoam/laminar/contaminatedDroplet2D/makePerturbation/makePerturbation.C b/tutorials/incompressible/pimpleFoam/laminar/contaminatedDroplet2D/makePerturbation/makePerturbation.C
index e4a9b01661..18130ca9d5 100644
--- a/tutorials/incompressible/pimpleFoam/laminar/contaminatedDroplet2D/makePerturbation/makePerturbation.C
+++ b/tutorials/incompressible/pimpleFoam/laminar/contaminatedDroplet2D/makePerturbation/makePerturbation.C
@@ -106,7 +106,7 @@ int main(int argc, char *argv[])
 
         vector r0(x, y, 0);
 
-        fsPatchU[pointI] = (scale - 1.0)*r0/runTime.deltaT().value();
+        fsPatchU[pointI] = (scale - 1.0)*r0/runTime.deltaTValue();
     }
 
     fixedValuePointPatchVectorField& fsPatchPointMeshU =
diff --git a/tutorials/incompressible/pimpleFoam/laminar/filmPanel0/system/sampling b/tutorials/incompressible/pimpleFoam/laminar/filmPanel0/system/sampling
index 8705a7f3a7..c38289f4b1 100644
--- a/tutorials/incompressible/pimpleFoam/laminar/filmPanel0/system/sampling
+++ b/tutorials/incompressible/pimpleFoam/laminar/filmPanel0/system/sampling
@@ -54,7 +54,7 @@ area
     libs    (utilityFunctionObjects);
 
     // Write at same frequency as fields
-    writeControl    outputTime;
+    writeControl    writeTime;
     writeInterval   1;
 
     fields          (U p hf_film );
diff --git a/tutorials/incompressible/pimpleFoam/laminar/sloshing2D/makeWave/makeWave.C b/tutorials/incompressible/pimpleFoam/laminar/sloshing2D/makeWave/makeWave.C
index 0910fa3e7a..74de4caf7f 100644
--- a/tutorials/incompressible/pimpleFoam/laminar/sloshing2D/makeWave/makeWave.C
+++ b/tutorials/incompressible/pimpleFoam/laminar/sloshing2D/makeWave/makeWave.C
@@ -100,7 +100,7 @@ int main(int argc, char *argv[])
             vector
             (
                 0,
-                a0*::cos(M_PI*x/L)/runTime.deltaT().value(),
+                a0*::cos(M_PI*x/L)/runTime.deltaTValue(),
                 0
             );
     }
diff --git a/tutorials/multiphase/icoReactingMultiphaseInterFoam/poolEvaporation/system/controlDict b/tutorials/multiphase/icoReactingMultiphaseInterFoam/poolEvaporation/system/controlDict
index cea2beec6c..f4191053b2 100644
--- a/tutorials/multiphase/icoReactingMultiphaseInterFoam/poolEvaporation/system/controlDict
+++ b/tutorials/multiphase/icoReactingMultiphaseInterFoam/poolEvaporation/system/controlDict
@@ -77,7 +77,7 @@ functions
         libs            (fieldFunctionObjects);
 
         field           T;
-        writeControl    outputTime;
+        writeControl    writeTime;
         writeInterval   1;
         htcModel        fixedReferenceTemperature;
         patches         (bottom);
@@ -90,7 +90,7 @@ functions
         libs            (fieldFunctionObjects);
 
         patches         (bottom);
-        writeControl    outputTime;
+        writeControl    writeTime;
         writeInterval   1;
     }
 }