Validation of Supersonic Film Cooling Modeling for Liquid Rocket Nozzle Applications

Abstract

Supersonic film cooling (SSFC) of nozzles has been used in several liquid rocket engine designs, and is being applied to the nozzle extension of the J-2X upper stage engine now under development. Due to the large size and challenging thermal load of the nozzle extension, there was a critical need to assess the accuracy of CFD models in representative SSFC flowfields. This paper reports results from a CFD analysis of SSFC experiments performed at Calspan in the late 1980s and early 1990s. 2-D and 3-D CFD simulations of flat plate heating, coolant nozzle flow, and film cooling flowfields are discussed and compared with the experimental data. For the film cooling cases studied, the 3-D simulations predict the initial mixing of the coolant and freestream in the adiabatic cooling region reasonably well. However, the CFD simulations generally predict faster mixing in the developed flow region of the flowfield than indicated by the experimental data. Hence, from an engineering perspective, the CFD tool and modeling assumptions used are conservative.

Effect of Coolant Inlet Conditions on Supersonic Film Cooling

“…Martin et al [12,13] used the large-eddy simulation method to study supersonic film cooling with the large-eddy simulation results agreeing well with experimental data and the results showing that the turbulent kinetic energy is significantly enhanced by the shock wave in the interaction area between the coolant gas and the mainstream. The numerical study of Christopher and Joseph [14] gave reasonable predictions of threedimensional supersonic film cooling for the initial mixing between the coolant and the mainstream in the adiabatic cooling region.…”

Film Cooling Effect on the Nosetip in Hypersonic Flow

“…The gas film cooling system is firstly used in combustion chamber of the aircraft gas turbine. And later a lot of research work are developed [7][8][9]. Supersonic film cooling have been studied since the 1960s, with early research being primarily experimental.…”