The regulation of propellant combustion using ultrasonic waves is proposed. Under ultrasonic frequencies of 25–40 kHz, we systematically examined the combustion characteristics of Al particles, ammonium perchlorate (AP)/hydroxyl-terminated polybutadiene (HTPB) propellants, and Al-containing Al/AP/HTPB propellants. Ultrasonic treatment increased the ignition delay time of the Al particles by 48.3 %. However, it increased the burning rate of the AP/HTPB propellants by up to 26.1 % and decreased their ignition delay by 39.3 %. As the ultrasonic frequency increased, the burning rate of the solid Al/AP/HTPB propellants increased by 22.5 %, and the degree of Al agglomeration decreased, resulting in a 24 % decrease in the size of the condensed-phase combustion products. The action mechanism was analyzed in terms of the effects of ultrasonic waves on Al droplets and combustion flames. The introduction of ultrasonic waves split the Al droplets near the burning surface into smaller particles, which affected combustion efficiency. Bringing the diffusion flame closer to the burning surface affected the burning rate. These findings demonstrate that the combustion and agglomeration characteristics of solid propellants can be modified using ultrasonic techniques, providing a new method for controlling the thrust of solid rocket motors.

中文翻译：

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超声技术在固体火箭推进剂燃烧促进中的首次应用


提出了利用超声波调节推进剂燃烧的方法。在 25–40 kHz 的超声频率下，我们系统地研究了 Al 颗粒、高氯酸铵 （AP）/羟基封端聚丁二烯 （HTPB） 推进剂和含 Al 的 Al/AP/HTPB 推进剂的燃烧特性。超声波处理使 Al 颗粒的点火延迟时间增加了 48.3 %。然而，它将 AP/HTPB 推进剂的燃烧速率提高了 26.1%，并将其点火延迟降低了 39.3%。随着超声频率的增加，固体 Al/AP/HTPB 推进剂的燃烧速率增加了 22.5 %，Al 团聚程度降低，导致凝聚相燃烧产物的尺寸减小了 24 %。根据超声波对 Al 液滴和燃烧火焰的影响分析了作用机理。超声波的引入将燃烧表面附近的 Al 液滴分裂成更小的颗粒，这影响了燃烧效率。使扩散火焰更靠近燃烧表面会影响燃烧速率。这些发现表明，可以使用超声技术改变固体推进剂的燃烧和团聚特性，为控制固体火箭发动机的推力提供了一种新方法。