爆轰波是一种强激波与化学反应耦合的物理现象，激波以数千米每秒速度 传播并在波后迅速放热，具有热效率高、放热迅速的特点，具有成为高超声速推 进系统的潜在应用方式。现有爆轰推进方式有脉冲爆轰、旋转爆轰、斜爆轰。斜 爆轰潜在工程应用有斜爆轰发动机与冲压加速器，由于斜爆轰推进具有自点火、 来流适应性强、理论热效率高等优势受到各国研究者的关注。工程应用需要控制 爆轰波的稳定性和推进效率，但对斜爆轰波进行精确调控的难度很大，主要原 因是对斜爆轰的机理，包括起爆的临界因素、自持传播的稳定性、淬灭机理等研 究尚存在较多的不足，因此需要对斜爆轰波起爆及自持传播机理开展深入研究， 以推进斜爆轰的工程应用。

斜爆轰作为燃烧与激波的耦合，存在两方面不稳定性特征影响其维持自持 稳定传播。一方面，在临近起爆/淬灭的临界状态其激波结构不稳定，较小的来 流状态改变会诱导不同的激波结构；另一方面，自持传播的爆轰波面上也存在 由燃烧不稳定性导致的流动结构变化。与这两方面对应的基础问题是起爆过程 与传播过程中斜爆轰激波结构、流动过程、波面精细结构的研究，它是获取斜爆 轰稳定机理、实现爆轰波调控的关键。针对上述斜爆轰的相关基础问题，开展了 高速弹丸诱导斜爆轰的机理研究. 首先基于高性能的爆轰驱动二级轻气炮发射装 置，设计了斜爆轰实验装置，实现了大速域范围内、不同起爆机理斜爆轰波起爆 与驻定，获得了不同状态爆轰波维持传播机理, 发展了先进的多序列激光阴影测 试技术, 获得了高空间分辨率的斜爆轰波波面精细结构阴影图像，揭示弹丸附近 波系与化学反应过程对斜爆轰波状态的影响机理，结合烟迹法第一次实现了斜 爆轰波胞格结构与尺寸测量，揭示了不同激波结构中斜爆轰波传播机理差异，结 合数值模拟，发现了影响现有临界理论适应性的流动机理。上述研究为建立基于 具体流动结构与化学反应机理的斜爆轰波临界理论与实现爆轰波调控提供科学 依据。本文的主要研究内容和研究成果如下：

(1) 研究了不同状态斜爆轰临界过程中激波结构的变化机理。针对来流参数 对激波结构不稳定性的影响，通过控制弹丸的状态及可燃气体初始参数，实现对 弹丸诱导不同激波结构的燃烧形式的区分；增强弹丸压缩作用有助于斜爆轰起 爆与维持驻定，影响其压缩能力的因素，包括弹丸外形与直径、弹丸速度、初始 压力；归纳了弹丸压缩能力变化与临界过程之间的联系，低于 C-J 爆轰速度起爆 的爆轰波受波后化学能释放影响无法驻定，高于 C-J 爆轰速度建立的爆轰结构由 膨胀波作用下爆轰波面能否淬灭决定。

(2) 开展了影响斜爆轰传播状态不稳定性的参数化研究。将斜爆轰波传播速 度这一体现了波后放热量与状态的关键因素作为控制参数，开展了斜爆轰传播 不稳定性的参数化研究。通过对比分析影响波面传播速度的攻角变化、起爆形 式、弹丸速度与初始压力的作用机理，获得了不同状态爆轰波传播状态的非定常变化机理。对于驻定斜爆轰其爆轰波面状态受弹丸附近膨胀波决定，弹丸速度 与攻角通过对膨胀波强度改变影响波面传播速度。草帽型爆轰波波面状态则由 化学反应过程决定，斜爆轰波面失稳后爆轰波传播速度下降导致过驱动度增加， 在波后化学放热支持下再加速形成自持传播的斜爆轰波。

(3) 揭示了不同状态下斜爆轰波燃烧与激波耦合机理。针对自持传播爆轰波 面上由燃烧不稳定性产生的波面精细结构，通过烟迹法开展了对斜爆轰横波胞 格结构、胞格尺寸的实验测量。分析了胞格形态、宽度与爆轰波面横波传播过程 的相关性，区分了不同结构下斜爆轰波横波传播机理，驻定斜爆轰中自持传播爆 轰波其横波尺寸与诱导区长度正相关，草帽型斜爆轰波横波尺寸与诱导区长度 负相关，发现爆轰波波面存在横波产生维持了不同位置胞格尺寸的一致。

(4) 开展了高速弹丸诱导斜爆轰波起爆机理的研究。通过对临界状态在不同 参数下的敏感性分析，发现现有临界理论的适用性存在不足。现有的仅考虑弹丸 压缩作用的临界理论不适用于化学反应动力学占主导的临界过程；爆轰波失稳 在弹丸附近，由弹丸外形产生的膨胀波主导，而远离弹丸处，失稳则由波面曲率 增加导致的膨胀波增强导致，膨胀波使化学反应诱导区增长导致了斜爆轰波解 耦淬灭。

The detonation wave is a combination of a strong shock wave and chemical reactions. Propagating at velocities of several kilometers per second, heat is released rapidly behind the shock wave. The detonation wave is characterized by high thermal efficiency and rapid heat release, making it potentially applicable in hypersonic propulsion systems. Detonation propulsion methods include pulse detonation, rotating detonation, and oblique detonation. The engineering applications of oblique detonation include oblique detonation engines and ram-accelerators. For advantages such as selfignition, strong adaptability to inflow, and high theoretical thermal efficiency, oblique detonation propulsion has garnered attention from researchers worldwide. Engineering applications necessitate controlling the stability and propulsion efficiency of detonation waves. However, precise control of oblique detonation waves is challenging due to the lack of thorough understanding of the mechanisms involved, including critical theory, stability, and quenching mechanisms. Therefore, in-depth research on the initiation and self-sustained propagation mechanisms of oblique detonation waves is needed to advance their engineering applications.

Oblique detonation, as a coupling of combustion and shock wave, exhibits two instability characteristics that affect its sustained and stable propagation. Firstly, near the critical condition of initiation/quenching, its shock wave structure becomes unstable, with slight changes in inflow conditions inducing different shock wave structures. Secondly, on the detonation wave front, there are fine flow structures caused by combustion instability. Corresponding to these two phenomena are fundamental issues regarding the structure of oblique detonation shock waves, flow processes, and fine structure of the wavefront during both initiation and propagation processes. Understanding these issues is crucial for elucidating the standing mechanisms of oblique detonation and achieving detonation wave control. To address the above fundamental issues of oblique detonation, research about the mechanisms of high-velocity projectile-induced oblique detonation has been conducted. Firstly, based on a high-performance detonation-driven twostage light gas gun facility, an oblique detonation experimental system was designed, enabling initiation and stabilization of oblique detonation waves with different initiation mechanisms over a wide range of velocities. This facilitated the acquisition of the mechanisms of the sustained propagation of detonation waves in different states. Advanced multi-sequence laser shadowgraph techniques were developed, providing high spatial resolution images of the fine structure of oblique detonation wavefronts. These images revealed the influence mechanisms of wave systems near projectiles and chemical reaction processes on the propagation process of oblique detonation waves. Thcellular structure and size of the oblique detonation wave were measured with soot foils for the first time. The differences in the propagation mechanisms of the oblique detonation wave in different shock wave structures were found. Moreover, through numerical simulations, flow mechanisms influencing the adaptability of existing critical theories were identified. The aforementioned research provides a scientific basis for establishing critical theories of oblique detonation waves based on flow-field structures and chemical reaction mechanisms, as well as for achieving detonation wave control. The main research content and achievements of this paper are as follows:

(1) The study investigated various shock wave structures during the critical process of oblique detonation under different states. Addressing the influence of inflow conditions on the instability of shock wave structure. The differentiation of the combustion process with different shock wave structures was achieved by changing the projectile and the combustible gas conditions. Enhanced projectile compression leads to initiating and sustaining oblique detonation. The factors affecting projectile compression capability include its shape and diameter, velocity, and initial pressure. The relationship between changes in projectile compression capability and the critical process was summarized. Below the Chapman-Jouguet (C-J) detonation velocity, the detonation wave propagates forward inability due to the influence of the chemical energy released behind the wave. Above the C-J detonation velocity, the establishment of detonation structures is determined by whether the detonation wave front can be quenched under the action of the expansion wave.

(2) A parameterized study was conducted to investigate the factors influencing the instability of oblique detonation propagation states. The propagation velocity of the oblique detonation wave, which embodies the critical factors of heat release and product condition behind the detonation wave, was selected as the control parameter for the parameterized study on the instability of oblique detonation propagation. Through comparative analysis of the effects of changes in angle of attack, initiation process, projectile velocity, and initial pressure on the wavefront propagation velocity, the transient variation mechanisms of detonation wave propagation states under different conditions were obtained. For a stabilized oblique detonation wave, the state of the detonation wavefront is determined by the expansion wave near the projectile. Projectile velocity and angle of attack affect the wavefront propagation velocity by altering the intensity of the expansion wave. In the case of a straw-hat oblique detonation wave, the state of the wavefront is determined by the chemical reaction process. After the instability of the oblique detonation wavefront, a decrease in the propagation velocity of the detonation wave leads to an increase in the overdrive, and under the support of chemical heat release behind the wave, the oblique detonation wave reaccelerates to form self-sustained propagation.

(3) The coupling mechanism between combustion and shock wave of oblique detnation wave under different states was elucidated. Regarding the fine structure of the wavefront generated by combustion instability on the self-sustained propagation detonation wavefront, experimental measurements of the transverse wave cellular structure and size of oblique detonation were conducted using the soot foils. The correlation between cell structure, width, and the transverse wave propagation process of the detonation wavefront was analyzed. Different propagation mechanisms of transverse waves of oblique detonation waves under different shock structures were distinguished. In stabilized oblique detonation, the number of transverse waves of the self-sustained propagation detonation wave is positively correlated with the length of the induction zone. In a straw-hat oblique detonation wave, the number of transverse waves is negatively correlated with the length of the induction zone. It was found that the detonation wavefront maintains consistent cell sizes at different locations through the generation of transverse waves.

(4) A study on the initiation mechanism of oblique detonation wave induced by high-velocity projectiles was conducted. Sensitivity analysis of the critical state under different parameters found that the applicability of existing critical theories is inadequate. The existing critical theories, which only consider the compressive effect of the projectile, are not suitable for critical processes dominated by chemical reaction kinetics. The instability of the detonation wave near the projectile is dominated by the expansion wave generated by the projectile’s shape, while instability away from the projectile is enhanced by the increase in wavefront curvature, leading to a strengthened expansion wave. Expansion waves cause the induction zone of chemical reactions to expand, resulting in the decoupling and quenching of oblique detonation waves.