Analytical Modeling of Supersonic Retropropulsion Plume Structures

摘要

The propulsive-aerodynamic interactions of a vehicle undergoing supersonic retropropulsion are heavily dependent on the configuration of the nozzles and their integration with the vehicle. Knowledge of the interaction effects is gained from wind-tunnel results as well as computational fluid dynamics simulations. Because of the complex flow field structures created by a vehicle employing supersonic retropropulsion, there are significant time and computational resource requirements to generate solutions for a particular configuration under specific flow conditions. Analytical flowfield models allow for preliminary information regarding flow structure to be available with minimal computational resources. By using these analytical models in the design process, the efficiency at which these studies can be performed can be improved by reducing the design space of nonfavorable designs and illustrating scenarios for higher-fidelity analysis. This paper proposes a method for analytically describing the plume boundaries present for two supersonic retropropulsion configurations: a single-nozzle and a three-nozzle configuration. The method is based on previous work on plume boundaries with modifications to account for the effects of a supersonic freestream. Comparisons with experimental data and computational simulations verify the model results for both configurations at Mach 2 and angle of attack of zero.