【摘要】 采用数值模拟和实验的方法研究不同喷管形式(收敛型,扩张型和收敛扩张型)和环境压力对火箭式脉冲爆震发动机(PDRE)比冲的影响。数值模拟中采用有限速率化学反应模型,通过二阶迎风格式差分逼近二维欧拉方程,数值计算结果表明收敛型喷管对比冲的增益最大(17.20%),环境压力为0.5 atm时比冲最大。不同喷管形式的实验中利用推力传感器测量得到比冲,结果同样表明收敛喷管的比冲增益最大(18.67%),且数值模拟和实验的结果基本吻合。分别采用理想性能模型和热力循环模型研究环境压力对PDRE比冲的影响。结果表明,在环境压力小于1 atm时,两种模型的分析和数值模拟均呈现不同的结果,因此低压环境下发动机的比冲影响规律有待进一步实验验证。更多还原

【Abstract】 The Numerical method was utilized to simulate the working performance of the PDRE.Specific impulse of the PDRE with different nozzles(convergent,divergent,convergent-divergent) was studied.It was found that PDRE with convergent nozzle could obtain the highest specific impulse,which was 17.20% higher than the cases without any nozzle.Ambient pressure was reduced to simulate the operation of the PDRE under vacuum condition.The results and their analysis show preliminarily that the low ambient pressure is beneficial for improving the working performance of PDRE,and 0.5atm is considered to be the optimum ambient pressure.更多还原