Numerical and experimental research on axial injection end-burning hybrid rocket motors with polyethylene fuel  

作　　者：Xiangyu MENG Hui TIAN Lingfei HE Jingfei GAO Xiaoting NIU Guobiao CAI 

机构地区：[1]School of Astronautics,Beihang University,Beijing 100191,China [2]Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies,Ministry of Education,Beijing 100816,China

出　　处：《Chinese Journal of Aeronautics》2024年第8期91-105,共15页中国航空学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.U20B2034);the Academic Excellence Foundation of Beihang University for PhD Students,China.

摘　　要：This study investigates the end-burning hybrid rocket motors with polyethylene fuel by the numerical simulation and experiment.Based on computational fluid dynamics,a numerical model is developed.The model is validated by two firing tests in this hybrid rocket motor,which uses oxygen and polyethylene as propellants.The results show that the numerical and experimental data are in good agreement,and the error of the chamber pressure is less than 2.63%.Based on the simulation mode,the blowoff limit of the end-burning hybrid rocket motors is investigated.When the nozzle throat diameter and the inner diameter of grain are large,it is more difficult for the hybrid rocket motor to achieve end-burning mode,i.e.,the flame spreading is prevented in the narrow duct.The main reason is that when the nozzle throat and the grain port are large,chamber pressure and oxidizer flow velocity are low.Therefore,the friction velocity considering the pressure and flow velocity is proposed.The critical friction velocity is about 4.054–4.890 m/s in the hybrid rocket motors.When the friction velocity exceeds the critical friction velocity,the combustion mode in hybrid rocket motors changes from the flame spreading mode to the end-burning mode.Moreover,the regression rate formula is obtained by fitting,which shows that the regression rate has a good correlation with combustion chamber pressure.The critical friction velocity and regression rate formula can provide an important reference for end-burning hybrid rocket motors.

关 键 词：Hybrid rocket motor End burning Blowoff limit Flame propagation Regression rate 

分 类 号：V436[航空宇航科学与技术—航空宇航推进理论与工程]