攻角动态变化对进气道起动特性的影响研究  

Study on the influence of dynamic change of attack angle on inlet start behavior

作　　者：孙志国 郭德春 李超 Sun Zhiguo;Guo Dechun;Li Chao(Beijing Aerospace Technology Institute,Beijing 100074,China)

机构地区：[1]北京空天技术研究所,北京100074

出　　处：《空天技术》2023年第5期22-32,共11页Aerospace Technology

摘　　要：宽速域飞行器采用机体/推进系统一体化设计,飞行器姿态的动态变化必然会影响到高速进气道的性能。选取二元压缩进气道模型为研究对象,采用非定常雷诺时均(URANS)方法和k-ωSST湍流模型,在给定的三种攻角动态变化条件下,研究了不同状态下的进气道非定常流场结构特征,分析了进气道起动/不起动演变过程和性能参数曲线变化规律。研究发现,在攻角余弦振荡变化条件下,当进气道处于起动状态时其性能参数形成了迟滞环,但迟滞引起的气动力/力矩变化幅度较小;当振荡周期内进气道出现起动/不起动转换时,气动性能曲线表现为首尾有差异的开式曲线,此时不起动的影响占据了主导,进气道性能大幅下降,其中流量系数下降了80%~90%、增压比减小了约79%。当进气道在俯仰振荡中由起动向不起动转换时,三种攻角动态变化方式对进气道性能也有明显影响,攻角阶梯变化条件下进气道最容易出现不起动,不同条件下的轴向力和流量系数差异最大可达到2~3倍。Wide-speed range vehicles are characterized by highly-integrated airframe and propulsion systems,so attitude variation on aircraft may have direct effects on the performance of hypersonic inlet.An unsteady Reynolds average Navier-stokes analysis for a 2-D scramjet inlet model has been performed based on the k-shear stress transport turbulence model.Three different change laws of inlet attack angle are taken to study unsteady flow physics in the hypersonic inlet un-start/starting process.The inlet characteristic parameters are also analyzed under the three different conditions.The numerical results show that the hysteresis phenomenon has been observed for inlet characteristic parameters,however hysteresis has less influence on the aerodynamic force and the moment when the inlet keeps start.If the inlet is converted from start to unstart in a cosine oscillation period,the curves of aerodynamic parameters become head-tail open ones.At the same time,characteristics of flow field and performances of inlet are mainly led by unstart conditions,the inlet performance has deceased seriously:the captured mass flow rate decreases by about 80%~90%and the compression ratio decreases by about 79%.When the inlet switches from start to unstart during oscillating pitching,the three disturbance conditions have an obvious impact on the aerodynamic performance of the inlet.The inlet is most likely to fail to start under the condition of step change in attack angle,the maximal difference for axial force and mass flow rate can be 2~3 times among the three conditions.

关 键 词：高速进气道 起动特性 激波干扰 非定常效应 重叠网格 

分 类 号：V229.7[航空宇航科学与技术—飞行器设计]