[Chintan-21]

Hello to All the team members


I hope you are having the good weekends and sorry to bother you in the weekends.


I am using the compressibleMultiphaseVoF solver for helical pipe simulation, and I am getting the following error message.


--> FOAM FATAL IO ERROR:
keyword sigmas is undefined in dictionary "/home/OpenFOAM/research_mesh_convergence/research_10k_comVOF/constant/phaseProperties"


Here below is my phaseProperties file


/--------------------------------- C++ -----------------------------------\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 11
\\/ M anipulation |
\---------------------------------------------------------------------------/
FoamFile
{
format ascii;
class dictionary;
location "constant";
object phaseProperties;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

type interfaceCompositionPhaseChangeMultiphaseSystem;

phases (gas liquid);

gas
{
type multicomponentPhaseModel;
diameterModel isothermal;
isothermalCoeffs
{
d0 1.6e-3; //sauter mean diameter of bubbles (change this when known)
p0 1e5; //atmospheric pressure
}

residualAlpha 1e-6; //convergence criteria
}

liquid
{
type multicomponentPhaseModel;
diameterModel constant;
constantCoeffs
{
d 1e-4;
}

residualAlpha 1e-6;
}

blending
{
default
{
type linear;
minFullyContinuousAlpha.gas 0.7;
minPartlyContinuousAlpha.gas 0.3;
minFullyContinuousAlpha.liquid 0.7;
minPartlyContinuousAlpha.liquid 0.3;
}

heatTransfer
{
type linear;
minFullyContinuousAlpha.gas 1;
minPartlyContinuousAlpha.gas 0;
minFullyContinuousAlpha.liquid 1;
minPartlyContinuousAlpha.liquid 0;
}

diffusiveMassTransfer
{
$heatTransfer;
}
}

surfaceTension
{
gas_liquid
{
type constant;
sigma 0.073; //0.0728 from engineering toolbox at 20C
}
}

drag
{
gas_dispersedIn_liquid
{
type SchillerNaumann;
}

liquid_dispersedIn_gas
{
type SchillerNaumann;
}
}

virtualMass
{
gas_dispersedIn_liquid
{
type constantCoefficient;
Cvm 0.5;
}

liquid_dispersedIn_gas
{
type constantCoefficient;
Cvm 0.5;
}
}

interfaceComposition
{
gas_liquid_inThe_gas // model for water becoming dissolved in the air
{
type saturated;
species ( water );
Le 1.0;
pSat ArdenBuck;
}

gas_liquid_inThe_liquid // model for o2 and n2 becoming dissolved in the water
{
type Henry;
species ( N2 O2 );
k (1.5e-2 3.2e-2); //dimensionless solubility constants for N2 and O2. Valid for temperatures around 280-300K
Le 1.0; //Lewis number. leave at 1.0

////SATURATED O2 at 20C is 9.1 mg/kg. (verfieid saturation with simulations!)
////SATURATED N2 at 20C is around 14 mg/kg. (verified saturation with simulations!)
}
}

heatTransfer
{
gas_dispersedIn_liquid_inThe_gas
{
type spherical;
residualAlpha 1e-4;
}

liquid_dispersedIn_gas_inThe_gas
{
type RanzMarshall;
residualAlpha 1e-4;
}

gas_dispersedIn_liquid_inThe_liquid
{
type RanzMarshall;
residualAlpha 1e-4;
}

liquid_dispersedIn_gas_inThe_liquid
{
type spherical;
residualAlpha 1e-4;
}
}

diffusiveMassTransfer
{
gas_dispersedIn_liquid_inThe_gas
{
type spherical;
}

liquid_dispersedIn_gas_inThe_gas
{
type Frossling;
Le 1.0;
}

gas_dispersedIn_liquid_inThe_liquid
{
type Frossling;
Le 1.0;
}

liquid_dispersedIn_gas_inThe_liquid
{
type spherical;
}
}

phaseTransfer
{}

lift
{}

wallLubrication
{}

turbulentDispersion
{}

interfaceCompression
{}

// ************************* //




I can see the sigma is define in the surface_tension section but I don't know why I am getting the error.


Any help would be greatly appreciated.




Regards
Chintan