摘要
斜爆轰技术具有结构简单、燃烧效率高和比冲高等优点,而试验条件的局限性限制了对斜爆轰的深入理解和该技术的进一步发展。基于反向爆轰驱动激波风洞直连试验系统,模拟了飞行高度30 km、马赫数9的来流条件,针对乙烯燃料进行了25°斜劈的斜爆轰波起爆试验。该系统通过激波管产生高温高压空气,经喷管加速后进入燃烧室,待空气流场建立后喷入燃料,与空气混合起爆。对斜爆轰波的结构特征及起爆过程进行观测与分析,在斜劈处形成了清晰的斜爆轰波系结构,准确识别出斜激波、斜爆轰波、横波和三波点等特征。在波后存在高亮度区域,表明了强烈化学反应的发生。斜爆轰波在试验中稳定时间约为6 ms,角度保持在80°±2°范围内,且试验具有良好的重复性。分析表明,试验中获得的斜爆轰波位于极曲线的过驱动强解区域。试验展示了斜爆轰波的起爆过程:燃料喷注前,斜劈前首先形成稳定的斜激波;燃料喷注后,斜激波与分离激波的交汇位置触发混合燃气起爆;起爆后形成的爆轰波面由化学反应支撑,逐渐向前推进,波面长度不断增加,直至达到稳定状态。最终,激波管内反射激波产生的高压破坏了斜爆轰波结构。
Oblique detonation technology offers significant advantages such as a simple structure,high combustion efficiency,and high specific impulse.However,limitations in ground-based experimental capabilities have hindered a deeper understanding of oblique detonation and the development of this technology.Based on a reverse detonationdriven shock tunnel directly connected system,this paper simulated a flight altitude of 30 km and a Mach number of 9 to make an experimental investigation of the initiation of oblique detonation waves with a wedge angle of 25°using ethylene fuel.The experimental system generates high-temperature and high-pressure air through a shock tube,which is then accelerated through a nozzle into the combustion chamber.Once the air flow field was established,fuel was injected and mixed with the air to initiate detonation.The structural characteristics and initiation process of the oblique detonation waves were observed and analyzed.Formation of a clear oblique detonation wave structure was found at the wedge.The features such as oblique shock waves,oblique detonation waves,transverse waves,and triple points were accurately identified.The high-brightness area behind the wave indicated intense chemical reactions.The oblique detonation wave remained stable for approximately 6 milliseconds,with the angle maintained within the range of 80°±2°.The experiments showed good repeatability.Analysis revealed that the experimentally obtained oblique detonation wave falls within the overdriven strong solution region of the extreme curve.The experiment detailed the initiation process of the oblique detonation wave.Before fuel injection,a stable oblique shock wave first formed at the front of the wedge.After fuel injection,the intersection of the oblique shock wave and the separation shock wave triggered the initiation of the mixed gas.The detonation wavefront formed after initiation was sustained by chemical reactions,gradually propagating forward with its length continuously increasing until reaching a stable state.Finally,the high pressure generated by the reflected shock wave in the shock tube disrupted the oblique detonation wave structure.
作者
张晓源
李进平
马虎
张仕忠
陈硕
陆星宇
ZHANG Xiaoyuan;LI Jinping;MA Hu;ZHANG Shizhong;CHEN Shuo;LU Xingyu(State Key Laboratory of High Temperature Gas Dynamics,Institute of Mechanics,Chinese Academy of Sciences Beijing 100190,China;School of Mechanical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China)
出处
《航空学报》
北大核心
2025年第9期230-240,共11页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金(11902328)
中国科学院院长基金(1702)。
关键词
斜爆轰
激波
起爆
波系结构
激波风洞
oblique detonation
shock
detonation initiation
wave structure
shock tunnel
