单组元300N发动机低温试验研究

Low Temperature Experimental Research on Mono-Propellant 300N Engine

关键词:  液体火箭发动机  单组元推进剂  低温  试验研究  起活时间

Key words:  Liquid rocket engine  Mono-propellant  Low temperature  Experiment  Activation time

摘要:

为探究低温环境下单组元300N发动机的工作特性，揭示影响发动机低温性能的主要影响因素，以300N发动机为试验对象，开展了模拟飞行工况的发动机低温试验。给出了低温试验研究方法，分别从温度差异对发动机性能影响、催化剂活性差异对发动机低温启动特性影响和低温对电磁阀响应特性影响等方面获得研究结果。结果表明，低温是影响发动机低温性能的主要影响因素，-48℃条件催化剂无法完成推进剂的催化分解，发动机发生爆炸；-30℃条件下起活时间为80.5～87.5ms，发动机可正常启动，且启动温度与起活时间呈指数关系；催化剂批次差异也对发动机低温工作性能产生一定影响，不同批次催化剂低温起活时间的差异可达91ms；低温试验过程中，电磁阀的关闭受到低温推进剂粘性和背压的影响，产生了明显的迟滞现象，延迟时间约100ms，对发动机在轨的精准控制存在一定影响。

Abstract:

In order to explore the working characteristics of the mono-propellant 300N engine in the low temperature environment and to reveal the main influencing factors， the low temperature environment experiments simulating flight environment were carried out taking the mono-propellant 300N engine as the experimental object. The research methods of low temperature experiments of 300N engine were given. The results of low temperature experiment were summarized from the effect of temperature difference on engine performance， catalyst activity difference on engine starting characteristics and low temperature on electromagnetic valve response characteristics. The results show that low temperature is the main factor on the performance of the 300N engine， the catalyst at -48°C cannot complete the catalytic decomposition of the propellant， and the engine works abnormally. The activation time at -30°C is 80.5~87.5ms， the engine can start normally， and there is an exponential relationship between starting temperature and activation time. The difference of catalyst batches also has a certain impact on the low-temperature performance of the engine. The activation time between different batches of catalysts can vary up to 91ms at low temperature. During the low temperature test， the closing time of the electromagnetic valve was affected by the viscosity of the low temperature propellant and the back pressure， resulting in obvious hysteresis. The delay time of control was about 100ms， which had a certain impact on the precise control of the engine.