复杂装药固体火箭发动机工作过程中阻尼特性分析

为了获得复杂装药发动机工作过程中阻尼特性的变化规律，首先利用有限元分析方法对不同工作时刻时的燃烧室声腔结构进行了数值仿真计算，得到复杂装药发动机工作过程中的声模态及其变化规律；基于此，计算并分析了复杂装药发动机装药燃烧过程中常见阻尼因素的变化规律，结果表明，喷管阻尼系数与壁面阻尼系数占总阻尼系数百分比逐渐减小，相反微粒阻尼系数占总阻尼系数的百分比逐渐增大，在发动机工作后期,发动机阻尼系数最小，从而导致发动机后期的工作稳定性较差，小扰动易被扩大为大扰动; 在发动机的所有阻尼中，喷管阻尼在发动机工作初期起主导作用，而微粒阻尼在工作后期起主导作用。

Analysis on Damping Characteristics of Solid Rocket Motor with Complicated Grain During Operation

In order to obtain the variation law of the damping characteristics of the rocket motor with complicated grain during the working process, the numerical simulation of the combustion chamber structure at different working moments was carried out before all others by using the finite element analysis method. And then, the acoustic modes and their variation law in the working process of the complex charge solid rocket motor were obtained. Based on this, the common damping factors in the combustion process of the complex charge solid rocket motor were calculated and analyzed. The results show that the percentage of nozzle damping coefficient and wall damping coefficient to total damping coefficient decreases gradually while the percentage of particle damping coefficient to total damping coefficient increases gradually. At the later stage of solid rocket motor operation, the damping coefficient of solid rocket motor is the smallest, which results in poor stability and small disturbance is easy to be enlarged. Among all the damping of the solid rocket motor, nozzle damping plays a dominant role in the early stage of solid rocket motor operation, while particle damping plays a dominant role in the later stage of solid rocket motor operation.