Compare of plug nozzle's heat transfer characteristics in different operation condition and with different coolant flow rate

To understand the different heat transfer characteristics of regenerative cooling in plug nozzle at different operating conditions, computational model of two dimensional plug nozzle and internal nozzle were established and numerical simulation was employed. Heat transfer results of the internal nozzle and the parameter distribution at the outlet were obtained. Flowfield and heat transfer characteristics of the plug at different operating conditions with different coolant flow rates were investigated. For calculation, governing equations were discretized with second order upstream scheme. The results show that at sea level, coolant flow rate affects the plug pressure, heat flux and temperature; at design operating condition, coolant flow rate has no effect on pressure and heat flux on the plug wall. With the same coolant flow rate, plug temperature at sea level is higher than that at design operating condition; under the same operating condition, ramp temperature is higher than the plug base temperature.