[durgesh.pandey]

I have to do a CFD analysis on a rocket payload(for academic purpose). I have a few doubts to start with:
1. What settings must be done in the ANSYS FLUENTsoftware for a payload which performs experiment in mesosphere if we want to find the temperature variations ?the conditions are turbulent, but there are several options for a turbulent model....which one should i pick? The payload will be ejected at a height of around 70km.
2. Secondly, should i go for a uniform mesh or a non-uniform mesh ? which will be accurate given that the geometry is very complex?
3. how to I take into account , in the software,the varying pressure the payload will be subjected to?
I cannot upload the design but if any of you guys can clear my doubts based on your experience, I would be grateful. Thanks