[ARUN K RAJ]

Hi All,

I would like to know some insight abt this equation referred in "UEqns.H" in twoPhaseEulerFoam solver used for solving multiphase problems. If someone can help me in understanding what each term here does in this equation will be helpful. I have some idea regarding these bt to crosscheck it, i need you help. I have listed the UEqn1 for convenience here:
U1Eqn =
(
(scalar(1) + Cvm*rho2*alpha2/rho1)*
(
fvm::ddt(U1)
+ fvm::div(phi1, U1, "div(phi1,U1)")
- fvm::Sp(fvc::div(phi1), U1)
)

- fvm::laplacian(nuEff1, U1)
+ fvc::div(Rc1)

+ fvm::div(phiR1, U1, "div(phi1,U1)")
- fvm::Sp(fvc::div(phiR1), U1)
+ (fvc::grad(alpha1)/(fvc::average(alpha1) + scalar(0.001)) & Rc1)
==
// g // Buoyancy term transfered to p-equation
- fvm::Sp(alpha2/rho1*K, U1)
//+ alpha2/rho1*K*U2 // Explicit drag transfered to p-equation
- alpha2/rho1*(liftCoeff - Cvm*rho2*DDtU2)
);
mrfZones.addCoriolis(scalar(1) + Cvm*rho2*alpha2/rho1, U1Eqn);
U1Eqn.relax();
}


and also what does surfaceScalarField phiR1
(
-fvc::interpolate(nuEff1)*mesh.magSf()*fvc::snGrad( alpha1)
/fvc::interpolate(alpha1 + scalar(0.001))
);
refer to in "UEqn.H"

I am using OF2.2.2 version. Thank you!