Computational simulation of cold supersonic jet exit from conical nozzle using FloEFD software package

To assure a soft landing, the descent vehicle of the manned transportation vehicle that is being designed at RSC Energia will use a parachute and rocket landing system. The solid-rocket landing propulsion system is to be operated in the immediate vicinity of the Earth surface, at the altitude of about 5-10 meters. The jets of the propulsion system have an impact on the aerodynamic properties of the descent vehicle during that mission phase and also affect the landing surface. The nozzles of the solid-rocket landing system have an unconventional shape - a rectangular throat with variable area, intricately shaped entry, and obliquely truncated exit section. Flows through such nozzles are poorly known and require special research. To determine the effects of the landing solid rocket jets on the aerodynamic properties of the descent vehicle and their impact on the landing surface within the framework of computer simulations, there are plans to use the FloEFD software package. In accordance with the computer simulation practice established at RSC Energia, industrial computations are preceded by test computations to validate the application of a software package to solving a particular problem. Selected for the purpose of testing the FloEFD package for its fitness to be used in the analysis of flow in the nozzles of the landing solid rocket was the problem of analyzing the exit of a cold supersonic air jet from an axially symmetric conical nozzle. The paper provides computation results and their comparison with experimental data.