What is density-weighted continuity equation
 

Hi everyone,

I found this term as I was reading a paper, so I was just wondering what it meant by density-weighted continuity equation? I'm not so sure if it applies for multiphase flow of two fluids in CFX. Does CFX implement this in their equation? If not, how do I do that? Or if someone could explain what the text below means that would be helpful as well. Thank you so much.

The part of the text from the paper I was reading: " we solve for six momentum equations, together with mass conservation and an equation for the phase fraction which involves the difference of the density-weighted continuity equations (leading to a constraint for continuity that ensures conservation of mass even in the early, not fully converged, stages of the computation)".

Have a look in a book about the Favre averaging method of the conservation equations.

I think the question is about the density weighed multiphase equations, not Favre averaging equations (which are used on equations like the momentum equation as an averaging approach to get Reynolds stresses, commonly in turbulence models).

The density weighted multiphase equations are explained in the CFX documentation, eqn 5-23 for continuity.

I will have a look at the documentations. Thank you very much!!