推进技术 ›› 2019, Vol. 40 ›› Issue (4): 804-814.

• 气动热力学 • 上一篇    下一篇

射流马赫数对圆弧形凹面腔内激波聚焦过程的影响

陈 鑫1,2,张威江1,王 川3,谭 胜4   

  1. 空军工程大学 航空工程学院,陕西 西安 710038; 先进航空发动机协同创新中心,北京 100191,空军工程大学 航空工程学院,陕西 西安 710038,中国人民解放军94795部队,江苏 南通 226000,国防科技大学 空天科学学院,湖南 长沙 410073
  • 发布日期:2021-08-15
  • 基金资助:
    国家自然科学基金青年科学基金(51106178)。

关键词:激波聚焦;径向入射;圆弧形凹面腔;射流马赫数

  1. Aeronautics and Engineering Institute,Air Force Engineering University,Xi’an 710038,China;Collaborative Innovation Center for Advanced Aero-Engine,Beijing 100191,China,Aeronautics and Engineering Institute,Air Force Engineering University,Xi’an 710038,China,Chinese People’s Liberation Army with Number of 94795,Nantong 226000,China and College of Aerospace Science and Engineering,National University of Defense Technology,Changsha 410073,China
  • Published:2021-08-15

摘要: 为研究射流马赫数对连续超声速射流对撞流场演化及激波聚焦过程的影响,保持入射导流深度L=0.00mm不变,通过更换不同的Laval喷管,对马赫数分别为Ma=1.2,1.4,1.6和1.8时的实验工况凹面腔内反射聚焦过程进行了实验研究,用高速CCD(Charge coupled device)拍摄了圆弧形凹面腔中气流流场纹影照片,并用动态压力传感器测量了聚焦过程中流场的压力变化,对径向入射激波在凹面腔内的反射聚焦过程进行了描述。通过对比不同射流马赫数下激波反射聚焦过程,发现在低马赫数1.2时,表现出较强的激波完全聚焦特性,即前导激波碰撞形成反射激波,并反射聚焦形成三波点,从而在凹腔底部形成高温高压区触发爆震,前导激波完全聚焦过程在凹面腔内流场演化中占据主导地位。随着马赫数的增加,完全聚焦强度降低,在流场中的主导优势逐渐减弱;其激波聚焦频率受射流马赫数的影响较小,频率差值较小,基本保持一致。

关键词: 激波聚焦;径向入射;圆弧形凹面腔;射流马赫数

Abstract: In order to study the effects of the jet Mach number on the evolution of continuous supersonic jet and the shock focusing process, keeping the depth of the deflector L=0.00mm constant, by replacing different Laval nozzle, experiments were carried out to investigate the radial incident shock focusing in cavity where the Mach number were 1.2, 1.4, 1.6, 1.8, respectively. The schlieren photos of flow field in cavity is captured by high-speed CCD camera, the dynamic pressure sensors is used to measure the pressure variation of the flow field during the focusing process, the behaviour of radial incident shock wave reflect and focus in a circular-shaped cavity was described. The shock wave focusing processes of different jet Mach number were compared, it is found that when the Mach number is 1.2, the perfect focusing characteristics of the shock wave are strong, that is, the leading shock wave collides to form the reflected shock wave, then the three-shock point is formed by the reflective focusing, thereby forming a high-temperature and high-pressure zone at the bottom of the cavity to trigger detonation. And the perfect focusing process of the leading shock wave occupies the dominant position in the flow field evolution of the cavity. With the increase of the Mach number, the perfect focusing intensity decreases, and the dominant advantage in the flow field gradually weakens; the focusing frequency of the shock wave is less affected by the jet Mach number, and the frequency difference is small and basically consistent.

Key words: Shock wave focusing;Radial incident;Circular-shaped cavity;Jet Mach number