Hi all, For my two phase flow where gas is dispresed, in the 'phase' boundary condition, i need to specify the bubble size what is the formula to find it and if liquid is dispersed, how to get the droplet size?

Hello Bala,

This is not a piece of cake. If u are assuming a uniform bubble size and assuming no break up and coalescence then u can do it in the phases panel. In the boundary conditions there is an inkt condition. In the inlet condition u can select ur dispersed or the secondary phase and u are all set. There is no formula to get the bubble size in the section however all I can say is that the bubble/ drop in ur section cannot be more than the diameter of the section. But in experiemnts u can find the maximum stable bubble size and then set accordingly. It all depends on what u use for simualting. I hope it Helps Podila.

What model are you using, It exist for both DPM and eulerian a model to compute break up and coalescence. For DPM you can set it in the default DPM panel. For eulerian solver, there is a UDF on the fluent website.