Euler-Euler simulation of evaporating spray

Xavier Ponticq

Hi All,

In my research project I'm dealing with evaporating sprays and want to compare Euler-Euler simulations to Euler-Lagrange simulations with CFX 11.0 (Euler-Lagrange simulations work fine). I wish to simulate the evaporation of a liquid spray in a gaz mixture composed of air and the liquid vapor. But I've some troubles in the set-up of mass transfert for evaporation.

I followed the modeling advice of CFX help by adding a dummy material to the liquid phase, but the results especially concerning the volume fraction are not satisfactory. Actually, using a dummy material as the constraint in the liquid phase implies that this dummy material appears from nowhere in the simulation as the pure liquid is evaporating. Thus I get a liquid volume fraction that is defined everywhere in the domain and not only where lies the liquid spray.

Adding a dummy material allows to use Component pairs models to describe the evaporation process. Without this dummy material I can't see how to use an evaporation model except by providing a value for the mass transfert coefficient. So, if you have any ideas....

Regards