微型拉瓦尔喷管的流体仿真分析和优化

FLUID SIMULATING ANALYSIS AND OPTIMIZATION OF MICRO LAVAL NOZZLE

采用Fluent软件对微型模块化液化气微推进系统的拉瓦尔喷管进行了流体仿真,得到了喷管各个尺寸因素对有效比冲和推力的影响曲线关系,并给出了喷管的最终优化结果。喷管有五个尺寸因素:入口直径、喉部直径、出口直径、收缩段长度和扩张段长度。其中,喉部直径越大,推力越大,有效比冲越小;出口直径越大,推力和有效比冲越大;收缩段长度较小时,对有效比冲影响较大,对推力几乎无影响;入口直径和扩张段长度对推力和有效比冲的影响很小可忽略。

The modular liquefied gas micro-propulsion system of Laval nozzle was simulated by using FLUENT software,and got each size of nozzle thrust and effective specific impulse,and gave the optimized results of nozzle.The nozzle has five sizes:inlet diameter,throat diameter,outlet diameter,contraction length and expansion length.Among them,the greater the throat diameter,the larger the thrust,the smaller the effective specific impulse;the greater the outlet diameter,the larger the thrust and effective specific impulse;when the contraction length is small,it affects the effective specific impulse,and almost has no effects on thrust;the effects of inlet diameter and expansion length are very small to be ignored.