OpenFOAM

1

19OpenCAE@ 2013/1/19

)(-) (-) (-)

(Interface Tracking) (Interface Capturing) ()

(MPS, SPH) VOF Level-Set Phase Field BFC() ALE(Arbitrary Lagrangian-Eulerian)

OpenFOAM

? VOF Level-Set Phase Field Front tracking BFC() ALE(Arbitrary Lagrangian-Eulerian)

VOFinterFoam

interFoam interDymFoam interMixingFoam ...

AMR(AdapVve Mesh Renement)

VOF

VOF(Volume of Fluid)

Navier-Stokes

sk

gPt

nF

Fvvvv

=

+++=+

2

0= v

VOF VOF

VOF

VOF

k:

:: liquid phase :: interface :: gas phase

1=

0=10

VOF

VOF VOFAMR CLSVOF VOF/PLIC VOF/SLIC VOF/WLIC VOF/IB CIP WENO

PLIC (Piecewise Linear Interface CalculaVon) SLIC (Simple Line Interface CalculaVon) WLIC (Weighted Line Interface CalculaVon)

2011 Cambridge Univ. Press (VOF, Front-Tracking, Level-Set )

VOF(InterFoam)

Dam Break (Tutorial)

VOF

VOFAMR(InterDymFoam)

Dam Break (Tutorial)

()

VOF

VOF VOFAMR CLSVOF VOF/PLIC VOF(THINC/WLIC) CIP ENO WENO

PLIC (Piecewise Linear Interface CalculaVon) SLIC (Simple Line Interface CalculaVon) WLIC (Weighted Line Interface CalculaVon)

CLSVOFOpenFOAM

VOF

// Need to store rho for ddt(rho, U) volScalarField rho ( IOobject ( "rho", runTime.VmeName(), mesh, IOobject::READ_IF_PRESENT ), alpha1*rho1 + (scalar(1) - alpha1)*rho2, alpha1.boundaryField().types() );

InterFoam

Navier-Stokes

sk

gPt

nF

Fvvvv

=

+++=+

2

:: liquid phase :: interface :: gas phase

1=

0=10

InterFoam

Navier-Stokes

sk

gPt

nF

Fvvvv

=

+++=+

2

:: liquid phase :: interface :: gas phase

1=

0=10 nu() ) );}

( ) 0=+

vt

InterFoam

Navier-Stokes

sk

gPt

nF

Fvvvv

=

+++=+

2

:: liquid phase :: interface :: gas phase

1=

0=10

InterFoam

Navier-Stokes

sk

gPt

nF

Fvvvv

=

+++=+

2

:: liquid phase :: interface :: gas phase

1=

0=10

InterFoam

Navier-Stokes

sk

gPt

nF

Fvvvv

=

+++=+

2

:: liquid phase :: interface :: gas phase

1=

0=10

Ueqn.H 19 if (momentumPredictor) { solve ( UEqn == fvc::reconstruct ( fvc::interpolate(rho)*(g & mesh.Sf()) + ( fvc::interpolate(interface.sigmaK())*fvc::snGrad(alpha1) - fvc::snGrad(p) ) * mesh.magSf() ) ); }

InterFoam

Navier-Stokes

:: liquid phase :: interface :: gas phase

1=

0=10

InterFoam

Navier-Stokes

:: liquid phase :: interface :: gas phase

1=

0=10

InterFoam

Navier-Stokes

:: liquid phase :: interface :: gas phase

1=

0=10

InterFoam

Navier-Stokes

:: liquid phase :: interface :: gas phase

1=

0=10

fvc::reconstruct OpenFOAM wiki + CFD online

InterFoam

Navier-Stokes

:: liquid phase :: interface :: gas phase

1=

0=10

InterFoamVer. 1.6.x

( ) ( )( ) 01 =++

rtvv

()

( ) ( )( ) 01 =++ dVdVdVdtd

V rVVvv

dVdsVs = aan

( ) dSdSdVdtd

SSV ++ nvnv r 1

InterFoamVer. 1.6.x

( ) dSdSdVdtd

SSV ++ nvnv r 1

( )( ) ff S nvr1( ) ff Snvf Sf

Sf

vn

OpenFOAM

InterFoamVer. 1.6.x

alphaEqn.H 5~8 surfaceScalarField phic = mag(phi/mesh.magSf());phic = min(interface.cAlpha()*phic, max(phic));surfaceScalarField phir = phic*interface.nHat();

fc S

=

))max(,min( ccc C =

fcr n=

=

fffr ss

Cn max,min

( )( ) ff S nvr1r??

InterFoamVer. 1.6.x

alphaEqn.H 5~8 surfaceScalarField phic = mag(phi/mesh.magSf());phic = min(interface.cAlpha()*phic, max(phic));surfaceScalarField phir = phic*interface.nHat();

nd, grep(src)

src/transportModels/interfaceProperVes/interfaceProperVes.C

cAlpha, nHat_, K_

InterFoamVer. 1.6.x

// Face unit interface normal ux nHat_ = nHatv & Sf;

// Simple expression for curvature K_ = -fvc::div(nHat_);

transportProperVesDict_(dict), cAlpha_ ( readScalar ( alpha1.mesh().soluVonDict().subDict("PISO").lookup("cAlpha") ) ),

src/transportModels/interfaceProperVes/interfaceProperVes.C

ffvf Snn =CSF (Brackbill (1992)) (ConVnuum Surface Force)

F = knsk =nf k =nn

C

131

117

146

InterFoamVer. 1.6.x

// Face unit interface normal surfaceVectorField nHatv = gradAlphaf/(mag(gradAlphaf) + deltaN_);

src/transportModels/interfaceProperVes/interfaceProperVes.C

113

nfv =( ) f

( ) f +N

deltaN_ ( "deltaN", 1e-8/pow(average(alpha1.mesh().V()), 1.0/3.0) ),

156

N =1.0108( Vi / NN )1/3

()

InterFoamVer. 1.6.x

alphaEqn.H 5~8 surfaceScalarField phic = mag(phi/mesh.magSf());phic = min(interface.cAlpha()*phic, max(phic));surfaceScalarField phir = phic*interface.nHat();

=

fffr ss

Cn max,min

( )( ) ff S nvr1

InterFoamVer. 1.6.x

alphaEqn.H 9~ for (int aCorr=0; aCorr

InterFoamVer. 1.6.x

=

fffr ss

Cn max,min )1( += r

( ) dSdSdVdtd

SSV ++ nvnv r 1

fS= v

( )( ) ff S nvr1

f

ff

f

fff S

Su

S

SuCn max,min

OpenFOAM

nfv =( ) f

( ) f +NN =

1.0108( Vi / NN )1/3

(nfv)

ffvf Snn =

:,:

InterFoam

OpenFOAMinterFoam

MULES OpenFOAM

References

J. U. Brackbill et al., J. Comp. Phys., 100, 335-354 (1992). G. Tryggvason et al., Direct Numerical SimulaVons of Gas-Liquid MulVphase Flows (Cambridge University Press, 2011)

OpenFOAM wiki (hpps://openfoamwiki.net/index.php/

OpenFOAM_guide/ReconstrucVon) CFD online (hpp://www.cfd-online.com/Forums/openfoam-

programming-development/77943-fvc-reconstruct-algorithm.html)