侧板构型对高超侧压进气道起动性能的影响

Impacts of Sidewall Geometry on Starting Characteristics of Side-Compression Hypersonic Inlet

关键词:  高超声速进气道  侧板  起动性能  数值模拟  风洞实验 

Key words:  Hypersonic inlet  Sidewall  Starting characteristics  Numerical simulation  Wind tunnel test

摘要:

为了考察侧板构型对高超侧压进气道起动性能的影响,对相同收缩比下侧板分别为前掠和后掠构型的进气道开展了Ma=4来流下的风洞实验及相应的数值模拟研究。实验结果表明,侧板后掠进气道的起动性能优于侧板前掠构型,实验中侧板后掠进气道能够在+2°攻角时实现起动,而侧板前掠进气道仅能在-2°攻角时起动。对流场进行的数值模拟结果表明,侧板后掠进气道不但比侧板前掠进气道具有更高的内收缩段入口马赫数,而且交汇后的侧板激波与底板边界层干扰的强度较弱,使得边界层不易分离,两方面因素共同作用使得侧板后掠进气道的起动性能显著优于侧板前掠构型。 

Abstract:

In order to investigate the impacts of sidewall geometry on the starting characteristics of the side-compression hypersonic inlet, one inlet with forward-swept sidewall and another with aft-swept sidewall having the same contraction ratio were tested in a Ma=4wind tunnel and the flow field was researched by CFD. The experimental results show that the inlet with aft-swept sidewall exhibits better capability of starting, which can start at the attack angle of +2°, comparing with the forward-swept sidewall inlet starting at the attack angle of -2°. The numerical results show that the Mach number of the lip surface of the aft-swept sidewall inlet is higher than that of the forward-swept sidewall inlet, and the intensity of the interaction between the intersected sidewall shock and the boundary layer of the bottom wall is much weaker, which is propitious for suppressing the separation of the bottom boundary layer. The above two reasons jointly account for the fact that the aft-swept sidewall is good for the side-compression hypersonic inlet to start. 