[Venky_94]

Hey,
I'm new to programming in OpenFOAM and I need to compile a variation of the interFoam solver, with modifications to the property determination method and the interface curvature calculation part of the CSF model to smoothen it.

I've attached an image with the changes I wish to make highlighted. I'm just not clear of where I'll have to go about making the changes. So any help in that regard will be extremely helpful.

1. So far what I've understood is that I can make the changes involving the property determination part in the incompressibleTwoPhaseMixture.C file, although there are multiple functions within that code where similar expressions are used, calcNu, mu, muf and nuf, and I'm not sure to which ones the changes are to be made.
2. Also I'm not sure where the changes for the curvature part is to be made.

[Venky_94]

I went through the solver source code, and this is my understanding about the changes, and further questions on which files need to be modified.

1. The property determination for viscosity should be changed for nu,mu,muf, and nuf in incompressibleTwoPhaseMixture.C file
2. Property determination for density should be changed in createFields.H and alphaEqnSubCycle.H?
3. The curvature part should be changed within Foam::interfaceProperties::calculateK() in interfaceProperties.C?
4. Also, how can I access the alpha values and area of the corresponding faces to implement the curvature correction?

[Venky_94]

Originally Posted by Venky_94

I went through the solver source code, and this is my understanding about the changes, and further questions on which files need to be modified.

1. The property determination for viscosity should be changed for nu,mu,muf, and nuf in incompressibleTwoPhaseMixture.C file
2. Property determination for density should be changed in createFields.H and alphaEqnSubCycle.H?
3. The curvature part should be changed within Foam::interfaceProperties::calculateK() in interfaceProperties.C?
4. Also, how can I access the alpha values and area of the corresponding faces to implement the curvature correction?

I was able to modify the property determination part for viscosity using the incompressibleTwoPhaseMixture.C file. But I went through the complete source code and I couldn't figure out where similar property determination for density is done before being used in the UEqn.H file. Can someone clarify at which point the "alpha1*rho1 + alpha2*rho2" sort of code is implemented in interFoam for density and from where the rho used in UEqn.H and PEqn.H is being sourced from?

[Venky_94]

Originally Posted by Venky_94

I was able to modify the property determination part for viscosity using the incompressibleTwoPhaseMixture.C file. But I went through the complete source code and I couldn't figure out where similar property determination for density is done before being used in the UEqn.H file. Can someone clarify at which point the "alpha1*rho1 + alpha2*rho2" sort of code is implemented in interFoam for density and from where the rho used in UEqn.H and PEqn.H is being sourced from?

Update:
I was able to update the expression for rho as well. rho is getting updated from alphaEqnSubCycle.H file. I missed it earlier as the expression had '==' operator which I got confused with the equality operator in C++, but openFOAM uses it as an assignment operator in this case. (Reference: == operator)

rho == alpha1*rho1 + alpha2*rho2;

I still need to figure out how to write a code to obtain the area-averaged volume fraction. Any suggestions in this regard would be extremely helpful.