src/lagrangian/dieselSpray/spraySubModels/breakupModel/reitzDiwakar/reitzDiwakar.C

   1 /*---------------------------------------------------------------------------*\
   2   =========                 |
   3   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   4    \\    /   O peration     |
   5     \\  /    A nd           | Copyright (C) 2011 OpenFOAM Foundation
   6      \\/     M anipulation  |
   7 -------------------------------------------------------------------------------
   8 License
   9     This file is part of OpenFOAM.
  10
  11     OpenFOAM is free software: you can redistribute it and/or modify it
  12     under the terms of the GNU General Public License as published by
  13     the Free Software Foundation, either version 3 of the License, or
  14     (at your option) any later version.
  15
  16     OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
  17     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  19     for more details.
  20
  21     You should have received a copy of the GNU General Public License
  22     along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 \*---------------------------------------------------------------------------*/
  25
  26 #include "error.H"
  27
  28 #include "reitzDiwakar.H"
  29 #include "addToRunTimeSelectionTable.H"
  30 #include "basicMultiComponentMixture.H"
  31
  32 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
  33
  34 namespace Foam
  35 {
  36     defineTypeNameAndDebug(reitzDiwakar, 0);
  37
  38     addToRunTimeSelectionTable
  39     (
  40         breakupModel,
  41         reitzDiwakar,
  42         dictionary
  43     );
  44 }
  45
  46 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
  47
  48 Foam::reitzDiwakar::reitzDiwakar
  49 (
  50     const dictionary& dict,
  51     spray& sm
  52 )
  53 :
  54     breakupModel(dict, sm),
  55     coeffsDict_(dict.subDict(typeName + "Coeffs")),
  56     Cbag_(readScalar(coeffsDict_.lookup("Cbag"))),
  57     Cb_(readScalar(coeffsDict_.lookup("Cb"))),
  58     Cstrip_(readScalar(coeffsDict_.lookup("Cstrip"))),
  59     Cs_(readScalar(coeffsDict_.lookup("Cs")))
  60 {}
  61
  62
  63 // * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
  64
  65 Foam::reitzDiwakar::~reitzDiwakar()
  66 {}
  67
  68
  69 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
  70
  71 void Foam::reitzDiwakar::breakupParcel
  72 (
  73     parcel& p,
  74     const scalar deltaT,
  75     const vector& vel,
  76     const liquidMixtureProperties& fuels
  77 ) const
  78 {
  79     const PtrList<volScalarField>& Y = spray_.composition().Y();
  80
  81     label cellI = p.cell();
  82     scalar pressure = spray_.p()[cellI];
  83     scalar temperature = spray_.T()[cellI];
  84     scalar Taverage = p.T() + (temperature - p.T())/3.0;
  85
  86     scalar muAverage = 0.0;
  87     scalar Winv = 0.0;
  88     forAll(Y, i)
  89     {
  90         Winv += Y[i][cellI]/spray_.gasProperties()[i].W();
  91         muAverage += Y[i][cellI]*spray_.gasProperties()[i].mu(Taverage);
  92     }
  93     scalar R = specie::RR*Winv;
  94
  95     // ideal gas law to evaluate density
  96     scalar rhoAverage = pressure/R/Taverage;
  97     scalar nuAverage = muAverage/rhoAverage;
  98     scalar sigma = fuels.sigma(pressure, p.T(), p.X());
  99
 100
 101     // The We and Re numbers are to be evaluated using the 1/3 rule.
 102
 103     scalar WeberNumber = p.We(vel, rhoAverage, sigma);
 104     scalar ReynoldsNumber = p.Re(vel, nuAverage);
 105
 106     scalar sqRey = sqrt(ReynoldsNumber);
 107
 108     if (WeberNumber > Cbag_)
 109     {
 110         if (WeberNumber > Cstrip_*sqRey)
 111         {
 112             scalar dStrip =
 113                 sqr(2.0*Cstrip_*sigma)
 114                /(
 115                     rhoAverage
 116                    *pow3(mag(p.Urel(vel)))
 117                    *muAverage
 118                 );
 119
 120             scalar tauStrip =
 121                 Cs_*p.d()
 122                *sqrt(fuels.rho(pressure, p.T(), p.X())/rhoAverage)
 123                /mag(p.Urel(vel));
 124
 125             scalar fraction = deltaT/tauStrip;
 126
 127             // new droplet diameter, implicit calculation
 128             p.d() = (fraction*dStrip + p.d())/(1.0 + fraction);
 129         }
 130         else
 131         {
 132             scalar dBag = 2.0*Cbag_*sigma/(rhoAverage*sqr(mag(p.Urel(vel))));
 133
 134             scalar tauBag =
 135                 Cb_*p.d()*sqrt(fuels.rho(pressure, p.T(), p.X())*p.d()/sigma);
 136
 137             scalar fraction = deltaT/tauBag;
 138
 139             // new droplet diameter, implicit calculation
 140             p.d() = (fraction*dBag + p.d())/(1.0 + fraction);
 141         }
 142     }
 143 }
 144
 145
 146 // ************************************************************************* //