Need help in proper CFD software
 

Hello everybody!
I've recently started my PhD Study and need some help to find proper CFD software for my work. I study in Aircraft and Rocket’s Construction field. My research work is supposed to be connected with evaluation and modeling of processes in aircraft engines. But also I'm very interested in other types of equipment used combustion processes like high-temperature chemical reactors etc.
I will need to use CFD software for modeling of such processes. And now I'm trying to find what would be the most suitable for me. I have a little experience with FlowVision, it's our local CFD software but unfortunately I think it wouldn't suit for such complicated things like mixing and combustion processes in aircraft engines for ex.
I've heard also about Star-CD and thinking about this software. There is also Fluent exists! What to choose?
If anyone with concrete experience in modeling of such processes could provide me with advice what software is the best for it I would be very thankful because just doing early steps in this field!
Awaiting for your answers and comments!:)