How to go about modeling injection nozzle two phase flow in FLUENT?
 

I trying to model liquid atomization and primary breakup in a converging- diverging nozzle using FLUENT. The geometry is attached below. It is a cross flow of water on a high speed jet combustion vapor. To start with am trying to model a cold flow simulation of water- air, which would create a spray at the exit. From my initial research of the problem in hand, i have decided to use Euler-Lagrange model. Gas phase described in Eulerian frame of reference and liquid phase using DPM model of FLUENT. Weber number of the liquid phase is high. At the throat region, speed is sonic (Mach no = 1). I am not sure what sort of atomizer model ( plain orifice or effervescent or any other) should i use to describe the liquid flow. In most of the built in atomizer model, the flow of two phases are co- axial. However, in my problem it is cross- flow.
So the primary question is how should i inject my liquid phase in DPM model of FLUENT? I would like to use blob injection model, so the initial diameter is that of the nozzle diameter and then use KHRT model to study the primary break up. In my problem, am interested in the primary break up, that is the region where it form liquid sheets, film for the core liquid. My aim to study the regime before the droplet formation.
Any sort of input, ideas are appreciated and it would help immensely in getting a step closer to solve the problem.