Merge branch 'master' of /home/noisy3/OpenFOAM/OpenFOAM-dev

applications/solvers/combustion/PDRFoam/PDRModels/XiEqModels/basicXiSubXiEq/basicXiSubXiEq.H

@@ -29,6 +29,36 @@ Description
     Basic sub-grid obstacle flame-wrinking enhancement factor model.
     Details supplied by J Puttock 2/7/06.
 
+    <b> Sub-grid flame area generation <\b>
+
+    \f$ n = N - \hat{\dwea{\vec{U}}}.n_{s}.\hat{\dwea{\vec{U}}} \f$
+    \f$ n_{r} = \sqrt{n} \f$
+
+    where:
+
+        \f$ \hat{\dwea{\vec{U}}} = \dwea{\vec{U}} / \vert \dwea{\vec{U}}
+        \vert \f$
+
+        \f$ b = \hat{\dwea{\vec{U}}}.B.\hat{\dwea{\vec{U}}} / n_{r} \f$
+
+    where:
+
+        \f$ B \f$ is the file "B".
+
+        \f$ N \f$ is the file "N".
+
+        \f$  n_{s} \f$ is the file "ns".
+
+    The flame area enhancement factor \f$ \Xi_{sub} \f$ is expected to
+    approach:
+
+    \f[
+        \Xi_{{sub}_{eq}} =
+            1 + max(2.2 \sqrt{b}, min(0.34 \frac{\vert \dwea{\vec{U}}
+            \vert}{{\vec{U}}^{'}}, 1.6)) \times min(\frac{n}{4}, 1)
+    \f]
+
+
 SourceFiles
     basicSubGrid.C
 

applications/solvers/combustion/PDRFoam/PDRModels/XiGModels/basicXiSubG/basicXiSubG.H

@@ -25,10 +25,28 @@ License
 Class
     basicSubGrid
 
+
 Description
+
     Basic sub-grid obstacle flame-wrinking generation rate coefficient model.
     Details supplied by J Puttock 2/7/06.
 
+    \f$ G_{sub} \f$ denotes the generation coefficient and it is given by
+
+    \f[
+        G_{sub} = k_{1} /frac{\vert \dwea{\vec{U}} \vert}{L_{obs}}
+                 \frac{/Xi_{{sub}_{eq}}-1}{/Xi_{sub}}
+    \f]
+
+    and the removal:
+
+    \f[ - k_{1} /frac{\vert \dwea{\vec{U}} \vert}{L_{sub}}
+    \frac{\Xi_{sub}-1}{\Xi_{sub}} \f]
+
+    Finally, \f$ G_{sub} \f$ is added to generation rate \f$ G_{in} \f$
+    due to the turbulence.
+
+
 SourceFiles
     basicSubGrid.C
 

applications/solvers/combustion/PDRFoam/PDRModels/dragModels/basic/basic.H

@@ -29,6 +29,50 @@ Description
     Basic sub-grid obstacle drag model.
     Details supplied by J Puttock 2/7/06.
 
+    <b> Sub-grid drag term <\b>
+
+    The resistance term (force per unit of volume) is given by:
+
+    \f[
+        R = -\frac{1}{2} \rho \vert \dwea{\vec{U}} \vert \dwea{\vec{U}}.D
+    \f]
+
+    where:
+
+        \f$ D \f$ is the tensor field "CR" in \f$ m^{-1} \f$
+
+        This is term is treated implicitly in UEqn.H
+
+    <b> Sub-grid turbulence generation <\b>
+
+    The turbulence source term \f$ G_{R} \f$ occurring in the
+    \f$ \kappa-\epsilon \f$ equations for the generation of turbulence due
+    to interaction with unresolved obstacles :
+
+    \f$ G_{R} = C_{s}\beta_{\nu}
+    \mu_{eff} A_{w}^{2}(\dwea{\vec{U}}-\dwea{\vec{U}_{s}})^2 + \frac{1}{2}
+    \rho \vert \dwea{\vec{U}} \vert \dwea{\vec{U}}.T.\dwea{\vec{U}} \f$
+
+    where:
+
+        \f$ C_{s} \f$ = 1
+
+        \f$ \beta_{\nu} \f$ is the volume porosity (file "betav").
+
+        \f$ \mu_{eff} \f$ is the effective viscosity.
+
+        \f$ A_{w}^{2}\f$ is the obstacle surface area per unit of volume
+        (file "Aw").
+
+        \f$ \dwea{\vec{U}_{s}} \f$ is the slip velocity and is considered
+        \f$ \frac{1}{2}. \dwea{\vec{U}} \f$.
+
+        \f$ T \f$ is a tensor in the file CT.
+
+    The term \f$ G_{R} \f$ is treated explicitly in the \f$ \kappa-\epsilon
+    \f$ Eqs in the PDRkEpsilon.C file.
+
+
 SourceFiles
     basic.C
 
@@ -40,7 +84,6 @@ SourceFiles
 #include "PDRDragModel.H"
 #include "XiEqModel.H"
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 namespace Foam
 {

applications/solvers/combustion/PDRFoam/PDRModels/turbulence/PDRkEpsilon/PDRkEpsilon.H

@@ -26,7 +26,17 @@ Class
     PDRkEpsilon
 
 Description
-    Standard k-epsilon turbulence model.
+    Standard k-epsilon turbulence model with additional source terms
+    corresponding to PDR basic drag model (basic.H)
+
+    The turbulence source term \f$ G_{R} \f$ appears in the
+    \f$ \kappa-\epsilon \f$ equation for the generation of turbulence due to
+    interaction with unresolved obstacles.
+
+    In the \f$ \epsilon  \f$ equation \f$ C_{1} G_{R} \f$ is added as a source
+    term.
+
+    In the \f$ \kappa \f$ equation \f$ G_{R} \f$ is added as a source term.
 
 SourceFiles
     PDRkEpsilon.C

applications/solvers/combustion/PDRFoam/XiModels/XiModel/XiModel.H

@@ -27,6 +27,57 @@ Class
 
 Description
     Base-class for all Xi models used by the b-Xi combustion model.
+    See Technical Report SH/RE/01R for details on the PDR modelling.
+
+    Xi is given through an algebraic expression (algebraic.H),
+    by solving a transport equation (transport.H) or a fixed value (fixed.H).
+    See report TR/HGW/10 for details on the Weller two equations model.
+
+    In the algebraic and transport methods \f$\Xi_{eq}\f$ is calculated in
+    similar way. In the algebraic approach, \f$\Xi_{eq}\f$ is the value used in
+    the \f$ b \f$ transport equation.
+
+    \f$\Xi_{eq}\f$ is calculated as follows:
+
+    \f$\Xi_{eq} = 1 + (1 + 2\Xi_{coeff}(0.5 - \dwea{b}))(\Xi^* - 1)\f$
+
+    where:
+
+        \f$ \dwea{b} \f$ is the regress variable.
+
+        \f$ \Xi^* \f$ is the total equilibrium wrinkling combining the effects
+        of the flame inestability and turbulence interaction and is given by
+
+        \f[
+            \Xi^* = \frac {R}{R - G_\eta - G_{in}}
+        \f]
+
+    where:
+
+        \f$ G_\eta \f$ is the generation rate of wrinkling due to turbulence
+        interaction.
+
+        \f$ G_{in} = \kappa \rho_{u}/\rho_{b} \f$ is the generation
+         rate due to the flame inestability.
+
+    By adding the removal rates of the two effects:
+
+        \f[
+            R = G_\eta \frac{\Xi_{\eta_{eq}}}{\Xi_{\eta_{eq}} - 1}
+              + G_{in} \frac{\Xi_{{in}_{eq}}}{\Xi_{{in}_{eq}} - 1}
+        \f]
+
+    where:
+
+        \f$ R \f$ is the total removal.
+
+        \f$ G_\eta \f$ is a model constant.
+
+        \f$ \Xi_{\eta_{eq}} \f$ is the flame wrinkling due to turbulence.
+
+        \f$ \Xi_{{in}_{eq}} \f$ is the equilibrium level of the flame wrinkling
+        generated by inestability. It is a constant (default 2.5).
+
 
 SourceFiles
     XiModel.C
@@ -51,6 +102,8 @@ namespace Foam
                           Class XiModel Declaration
 \*---------------------------------------------------------------------------*/
 
+
+
 class XiModel
 {
 

applications/solvers/combustion/PDRFoam/laminarFlameSpeed/SCOPE/SCOPELaminarFlameSpeed.H

@@ -28,6 +28,33 @@ Class
 Description
     Laminar flame speed obtained from the SCOPE correlation.
 
+    Seven parameters are specified in terms of polynomial functions of
+    stoichiometry. Two polynomials are fitted, covering different parts of the
+    flammable range. If the mixture is outside the fitted range, linear
+    interpolation is used between the extreme of the polynomio and the upper or
+    lower flammable limit with the Markstein number constant.
+
+    Variations of pressure and temperature from the reference values are taken
+    into account through \f$ pexp \f$ and \f$ texp \f$
+
+    The laminar burning velocity fitting polynomial is:
+
+    \f$ Su = a_{0}(1+a_{1}x+K+..a_{i}x^{i}..+a_{6}x^{6}) (p/p_{ref})^{pexp}
+    (T/T_{ref})^{texp} \f$
+
+    where:
+
+        \f$ a_{i} \f$ are the polinomial coefficients.
+
+        \f$ pexp \f$ and \f$ texp \f$ are the pressure and temperature factors
+        respectively.
+
+        \f$ x \f$ is the equivalence ratio.
+
+        \f$ T_{ref} \f$ and \f$ p_{ref} \f$ are the temperature and pressure
+        references for the laminar burning velocity.
+
+
 SourceFiles
     SCOPELaminarFlameSpeed.C
 
@@ -125,7 +152,7 @@ class SCOPE
         //  corrected for temperature and pressure dependence
         inline scalar Su0pTphi(scalar p, scalar Tu, scalar phi) const;
 
-        //- Laminar flame speed evaluated from the given uniform 
+        //- Laminar flame speed evaluated from the given uniform
         //  equivalence ratio corrected for temperature and pressure dependence
         tmp<volScalarField> Su0pTphi
         (
@@ -134,7 +161,7 @@ class SCOPE
             scalar phi
         ) const;
 
-        //- Laminar flame speed evaluated from the given equivalence ratio 
+        //- Laminar flame speed evaluated from the given equivalence ratio
         //  distribution corrected for temperature and pressure dependence
         tmp<volScalarField> Su0pTphi
         (
@@ -144,7 +171,7 @@ class SCOPE
         ) const;
 
         //- Return the Markstein number
-        //  evaluated from the given equivalence ratio 
+        //  evaluated from the given equivalence ratio
         tmp<volScalarField> Ma(const volScalarField& phi) const;
 
         //- Construct as copy (not implemented)