Unexpected pressure rise may occur in the end-burning grain solid rocket motor. It is generally believed that this phenomenon is caused by the nonparallel layer combustion of the burning surface, resulting in the increase of burning rate along the inhibitor. In order to explain the cause of this phenomenon, the experimental investigation on four different end configurations were carried out. Based on the X-ray real-time radiography (RTR) technique, a new method for determining the dynamic burning rate of propellant and obtaining the real-time end-burning profile was developed. From the real-time images of the burning surface, it is found that there was a phenomenon of nonuniform burning surface displacement in the end-burning grain solid rocket motor. Through image processing, the real-time burning rate of grain center line and the real-time cone angle are obtained. Based on the analysis of the real-time burning rate at different positions of the end surface, the end face cone burning process in the motor working process is obtained. The closer to the shell, the higher the burning rate of the propellant. Considering the actual structure of this end-burning grain motor, it is speculated that the main cause of the cone burning of the grain may be due to the heat conduction of the metal wall. By adjusting the initial shape of the grain end surface, the operating pressure of the combustion chamber can be basically unchanged, so as to meet the mission requirements. The results show that the method can measure the burning rate of solid propellant in real time and provide support for the study of nonuniform combustion of solid propellant.

中文翻译：

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基于X射线实时射线照相的固体末推进剂燃烧速率增强分析。

最终燃烧谷物固体火箭发动机中可能发生意外的压力上升。通常认为，这种现象是由燃烧表面的非平行层燃烧引起的，导致沿抑制剂的燃烧速率增加。为了解释这种现象的原因，对四种不同的末端结构进行了实验研究。基于X射线实时射线照相（RTR）技术，开发了一种确定推进剂动态燃烧速率并获得实时最终燃烧曲线的新方法。从燃烧表面的实时图像发现，在末端燃烧谷物固体火箭发动机中存在燃烧表面位移不均匀的现象。通过图像处理 得到了粮食中心线的实时燃烧率和实时锥角。通过对端面不同位置的实时燃烧速率的分析，得出了电机工作过程中端面锥面的燃烧过程。离壳体越近，推进剂的燃烧速率越高。考虑到这种谷物燃烧机的实际结构，可以推测谷物锥体燃烧的主要原因可能是由于金属壁的热传导。通过调节晶粒端面的初始形状，燃烧室的工作压力可以基本保持不变，从而满足任务要求。