旁路式双喉道喷管气动矢量特性数值研究

Numerical Investigation on Aerodynamic Vector Performance of Bypass Dual Throat Nozzle

旁路式双喉道喷管(BDTN)通过设置旁路通道即可实现稳定的推力矢量,无需增加额外的高压气源和次流系统,研究其推力矢量特性对于提高飞行器的机动性和敏捷性具有重要意义。采用数值方法对BDTN在不同落压比下的内外流场及其在高温高压环境下的内流特性进行数值仿真。结果表明:BDTN的流场结构与普通双喉道喷管(DTN)相仿,但矢量效果更好,可在推力系数为0.966的同时获得24.6°的推力矢量角;落压比(NPR)大于4时,随着入口总压的增加,喷管推力矢量角和推力系数均逐渐减小;在入口总温为3 000K、落压比为100时,喷管的推力矢量角减小至12.75°,推力系数减小至0.882,即高温高压的内流环境对喷管矢量性能具有很大的消极影响。

Bypass dual throat nozzle(BDTN)can achieve stable thrust vector by setting the bypass channel,without increasing the pressure source and the secondary flow of the additional system.Thrust vector characteristics is of important significance to improve vehicle maneuverability and agility.Numerical studies are performed to analyze the thrust vectoring performances of a bypass dual throat nozzle(BDTN)under different conditions.The main results show that:BDTN has the same flow filed structure with the conventional dual throat nozzle(DTN),but can generate a better thrust vectoring performance with producing more steady and efficient vectoring effect.A thrust vector angle of24.6°is obtained with little thrust penalty.The thrust vector angle and the thrust ratio are decreasing with nozzle pressure ratio(NPR)increasing.The high temperature and high pressure can lead to the thrust vectoring efficiency loss tremendously with the thrust vector angle decrease to12.75°and the thrust ratio decrease to0.882.