摘要
利用内径为30mm,长度为1 000mm的爆轰管,对脉冲爆轰发动机进行研究.爆轰管内充满氢气-氧气-氮气预混气,采用底端中心点火.对半球形高温火团引发的氢气-氧气-氮气爆轰过程和管内、外流场分布进行轴对称数值模拟,考虑了H_2-O_2-N_2的详细化学反应动力学机理,该机理包含了19个基元反应和9种组份.实验和计算获得的外流场阴影和数值照片,形象地描述了管外流场的变化.数值计算结果和实验结果基本一致,根据实验和数值计算结果,详细地讨论了悬吊激波产生的动力学机理.爆轰波溢出爆轰管后,斜压效应和Helmholtz不稳定导致涡环的产生,同时在流场中形成止于涡环的悬吊激波,涡环形状的变化又引起悬吊激波的强度、形状和位置的变化.
Pulse Detonation Engine (PDE) tests in the PDE tube H2-O2-N2 have been performed with central ignition in the tube end. The tube has 1000 mm long with the inner diameterof 30 mm, filled with the H2-O2-N2 mixture. Moreover, numerical simulations of pulse detonation process induced by flame in the tube with H2- O2-N2 mixture and the distribution of the internal and external flow field were performed. A detailed chemical mechanism of H2-O2-N2 system was investigated with 19 element reactions and 9 species. The generation and development of the vortex ring and suspended shock were exhibited with the sequential shadowgraphs of the external flow field both in test and simulation. The numerical results were in good agreement with the measured results. The experimental and numerical results show that the vortex ring was induced by baroclinic effect and Helmholtz instability in the vicinity of the thruster exit after the donation wave exhausted the tube. The intensity, shape and location of the suspended shock varied when the shape of the vortex ring changed.
出处
《力学学报》
EI
CSCD
北大核心
2009年第1期28-34,共7页
Chinese Journal of Theoretical and Applied Mechanics
基金
国家自然科学基金(50336030)
中国科学院高温气体动力学重点实验室基金资助项目~~