Development of a Laval nozzle for a cold gas propulsion system

6th ModTech International Conference - Modern Technologies in Industrial Engineering

Dumitrescu, O.^1 ; Gherman, B.^1 ; Tipa, T.^1

National Research and Development Institute for Gas Turbines COMOTI, 220 D Iuliu Maniu Bvd., Bucharest, Romania^1

关键词: Analytical results;    Characteristics method;    Cold gas propulsion system;    Commercial software;    Inert properties;    Main parameters;    Propulsion system;    Solar thermal propulsion system;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/400/4/042016/pdf
DOI  :  10.1088/1757-899X/400/4/042016

来源: IOP

【 摘 要 】

This paper presents a study regarding the calculation and design of a Laval nozzle, and its influence on the performances obtained. For this research, numerical simulation were conducted using the commercial software ANSYS CFX to verify the geometry and to compare it with the analytical results. This study is part of a research project that develops an advanced solar thermal propulsion system; the main purpose is to increase the operation life of a satellite using focused solar light. Two geometries are analyzed in this paper: one with a cone shape and the other generated using the characteristics method. The working fluid is nitrogen gas, which was used due to its inert properties and high molar mass. For the numerical simulations an exterior domain has been taking into account, to capture the jet and to observe how is evolving into the atmosphere. Several cases were studied; temperature was the main parameter varied from one case to another. As a result of the numerical simulations, it was found that the nozzle shape and temperature at the inlet to the convergent section influences performance of the propulsion system in a significant manner. Mach diamonds form because of the supersonic exhaust of the nozzle, and can be seen how their intensity is decreasing in magnitude near the domain outlet.