[Caramel]

Hello, everyone.

I am new to dealing with fluent.
Since no one in my lab has done numerical analysis in the past, I am having a lot of trouble in proceeding with the analysis.

I am doing a numerical analysis of the inside of the combustion chamber of a hybrid rocket in 2D. (Please refer to the picture for the model. The model is for an axis.)
I am assuming that the oxidizer (oxygen) flows out of the inlet on the right, and the fuel (kerosene air mixture) melts and flows out of the upper and lower inlets.

(1) I am not sure whether to use the fuel inflow as velocity or mass flow. I have calculated the flux and mass flow rate for the fuel based on the fuel recession rate, but which should I use?

(2) When I run the numerical analysis with the fuel as flow velocity, the combustion reaction does not occur properly. What should I do to set the analysis conditions?

I would like to thank everybody in advance.
Kanami