一种基于横向压力控制的前体流动特性分析

Investigations on Flow Characteristics of Forebody Based on Spanwise Pressure Control

关键词:  前体构型  攻角  横向压力梯度  流量捕获  升阻比  高超声速  进气道

Key words:  Forebody configuration  Attack angel  Spanwise pressure gradient  Mass flow capture  Lift-to-drag ratio  Hypersonic  Inlet

摘要:

为了探究前体构型对进气道气动特性的影响，在相同的压缩角度及几何长度下，设计了升力体前体和类乘波体前体两种构型方案。就不同构型对前体/进气道气动特性的影响开展了三维数值模拟研究，并与进气道二维流动进行了对比分析。结果显示，相比于进气道二维流动，三维升力体和类乘波体前体构型在设计状态和不同来流攻角下均存在一定的横向压力梯度，导致进气道流量捕获能力降低，与二维流动差异较大，前者流量系数下降20.3%，后者下降9.0%。相比较而言，类乘波体前体在流量捕获能力及升阻比等方面性能更优。增大类乘波体前体宽度比和前缘角度，可以减小前体横向压力梯度，提高前体/进气道的流量捕获能力，前者提高了升阻比，而后者则降低了升阻比。

Abstract:

In order to investigate the effects of forebody configurations on inlet aerodynamic performances，two forebody configurations，namely lifting forebody and waverider-like forebody，were designed with the same compression angle and geometry length. 3D numerical simulations were conducted to explore the impact of forebody/inlet with different configurations on aerodynamic performances. Compared with 2D flows，results show that under on-design status and states with different attack angels，both two forebody configurations have spanwise pressure gradients，causing the decrease of inlet mass flow rate and evident differences in comparison with 2D flows，specifically，the former case dropped by 20.3% in mass flow coefficient and the later one declined by 9.0%. The waverider-like body has advantages in terms of mass flow capture and lift-to-drag ratio over lifting body. Increasing parameters of width ratio and leading angle is able to reduce the spanwise pressure of forebody and enhance the capacity of mass flow capture. The former approach improves the lift-to-drag ratio，and the reversed trend is applied to the later one .