基于前缘边界层扰动的空腔压力脉动抑制研究

发布时间：2018-02-14 01:02

本文关键词： 空腔斜劈气动噪声抑制方法声压级声压频谱　出处：《实验流体力学》2016年03期 　论文类型：期刊论文

【摘要】：武器内埋是实现战斗机超声速巡航、低可探测性(隐身)等先进技术指标的关键气动布局措施之一。腔内流场结构复杂,在一定条件下存在严重压力脉动,诱发强烈噪声,声压级(SPL)甚至可高达170dB,可能造成结构与内部元器件的破坏,因此空腔噪声与抑制方法成为研究热点之一。为此,对亚、跨声速流动条件(Ma=0.6、0.95和1.2)下有、无斜劈(ramps)时过渡式空腔(长深比L/D=4)气动声学特性开展了风洞试验研究,通过综合对比分析空腔底面中心线上的声压级分布和不同测点的声压频谱(SPFS)特性,探讨了斜劈对空腔气动噪声的抑制效果。研究结果表明,在亚、跨声速条件下,采用前缘斜劈对空腔内噪声有一定抑制效果,使得空腔后部区域声压级降低幅度比前部区域大,同时对空腔前壁以及后壁噪声也有抑制效果,部分典型测点声压频谱曲线上的能量尖峰基本全部被削平,这表明空腔流场已不存在产生自持振荡的流动机制。
[Abstract]:Weapon burying is one of the key aerodynamic layout measures to realize advanced technical indexes such as supersonic cruise, low detectability (stealth) and so on. The structure of flow field in the cavity is complex, and there is serious pressure pulsation under certain conditions, which induces strong noise. Sound pressure level (SPLL) can even be as high as 170 dB, which may cause damage to the structure and internal components. Therefore, cavity noise and suppression methods have become one of the research hotspots. In this paper, the aerodynamic acoustic characteristics of transition cavity (L- / D4) without slanting wedge are studied by wind tunnel test. The distribution of sound pressure level on the center line of cavity bottom and the characteristics of sound pressure spectrum of different measuring points are analyzed synthetically through wind tunnel test. In this paper, the effect of oblique wedge on the aerodynamic noise of cavity is discussed. The results show that under the condition of subsonic velocity and transonic velocity, the front edge wedge can suppress the noise in the cavity to a certain extent, which makes the reduction of sound pressure level in the rear part of the cavity greater than that in the front area. At the same time, the noise of the front wall and back wall of the cavity is also suppressed, and the energy spike on the spectrum curve of sound pressure of some typical measuring points is basically reduced, which indicates that there is no flow mechanism of self-sustaining oscillation in the cavity flow field.
【作者单位】：中国空气动力研究与发展中心高速空气动力研究所;
【基金】：国家自然科学基金(11372337)
【分类号】：V211.4

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