Thermal plume
 

Hello Every one
I am trying to simulate thermal plume from a nozzle exit and for that i am referring "Study on infrared signature of solid rocket motor afterburning exhaust plume" Paper. For details about geometry, boundary conditions and solver settings please refer attached images. mass momentum and energy equations are not converging. please suggest me if i did any thing wrong while assigning boundary conditions or solver settings. (mesh is very fine)

http://postimg.org/image/4zut4r7hx/

http://postimg.org/image/iut3n81x1/

http://postimg.org/image/9oaszxwol/