补燃发动机完全自身起动过程富氧燃气温度控制

Temperature control of oxygen-riched gas during complete self start-up process for staged combustion cycle engine

为了防止富氧补燃循环发动机在完全自身起动过程中出现烧蚀情况,需要研究降低发生器富氧燃气温度峰值的方法。利用成熟的发动机组件数学模型,建立了发动机完全自身起动过程动态仿真模型,并通过试验数据验证了仿真模型的合理性。基于计算结果,分析了起动过程中发生器富氧燃气温度的变化过程,进一步分析了产生3个温度极大值的原因。通过仿真研究,分析了不同起动参数对富氧燃气温度峰值的影响。结果表明:提高发生器氧化剂流量和减缓发生器燃料流量增速可以降低富氧燃气温度峰值,具体措施有提高氧化剂贮箱压力、减小供应管路长度、提高副路转级阀的作动压力和减小其转级速率。

To avoid the ablation during the complete self-starting process of staged combustion cycle engine using an oxidant gas generator,it is necessary to study the method of reducing the peak temperature of oxygen-riched gas.Using the mature mathematical model of engine components,a transient simulation model of engine self-starting process was established,and it was validated by the test data.Based on the calculation results,the temperature change of oxygen-riched gas in the generator during the start-up process was analyzed,and the reason for the three temperature maxima was further analyzed.The influence of different starting parameters on the peak temperature of oxygen-riched gas was analyzed by means of the numerical simulation.The results show that several solutions could be taken to control the peak temperature during start-up process,including improving the oxidizer flow and slowing down the growth rate of secondary fuel flow.The specific measures include increasing the oxidizer tank pressure,reducing the length of supply line,increasing the actuation pressure of stage valve and reducing its conversion rate.