Study on the Development Mechanism of Detonation Wave for the Hydrogen-Oxygen Mixture in a Shock Tube
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摘要: 针对气相爆轰波成长机制研究,采用压力传感器和高速摄影技术,测试了氢氧混合气体在点火后的火焰波、前驱冲击波以及爆轰波的成长变化过程,计算了冲击波过程参数和气体状态参数,分析了火焰加速机制。实验结果表明,APX-RS型高速摄影系统可用于拍摄气相爆轰波的成长历程;氢氧爆轰波的产生是由于湍流火焰和冲击波的相互正反馈作用,导致反应区内多处发生局部爆炸,爆炸波与冲击波相互耦合,最终成长为定常爆轰波。Abstract: This paper mainly focuses on the experimental investigation of the gaseous detonation wave build-up mechanism for hydrogen-oxygen mixture in shock tube. Five pressure sensors were used to record the pressures and a high-speed camera was used to capture velocities of flame, shock, or detonation wave. The high-speed camera records the transformation of flame, shock in the ignition phase and the attenuation of detonation wave. The experimental results show that the diagnostic system can effectively measure the DDT. The images of flame propagation show that the flame front is curving and dispersive. It is found that the interaction of shock and turbulent flame is a dominant factor for the onset of explosion. In the smooth tube, experiments indicate that the intensity of shock wave continually increases due to the acceleration of flame. The local explosion occurs in the reaction zone when the intensity of shock wave arrives at a critical pressure pc when some hot spots form in the local explosion centers. At that time, an unsteady detonation wave is formed immediately, and after a period of the propagation or attenuation process, it eventually evolves into a steady detonation wave.
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Lee J H S, Knystautas R, Freiman A. High Speed Turbulent Deflagrations and Transition to Detonation in H2-Air Mixtures [J]. Combust Flame, 1984, 56(2): 227-239. Brown C J, Thomas G O. Experimental Studies of Shock-Induced Ignition and Transition to Detonation in Ethylene and Propane Mixtures [J]. Combust Flame, 1999, 117(4): 861-870. Thomas G O, Bambrey R J, Brown C. Experimental Observations of Flame Acceleration and Transition to Detonation Following Shock-Flame Interaction Combust [J]. Combustion Theory and Modelling, 2001, 5(4): 573-594. Thomas G O, Bambrey R J. Some Observations of the Controlled Generation and Onset of Detonation [J]. Shock Waves, 2002, 12(1): 13-21. Card J, Rival D, Ciccarelli G. DDT in Fuel-Air Mixtures at Elevated Temperatures and Pressures [J]. Shock Waves, 2005, 14(3): 167-173. Li J, Lai W H, Chung K, et al. Uncertainty Analysis of Deflagration-to-Detonation Run-up Distance [J]. Shock Waves, 2005, 14(5-6): 413-420. Kersten C, Frster H. Investigation of Deflagrations and Detonations in Pipes and Flame Arresters by High-Speed Framing [J]. Journal of Loss Prevention in the Process Industries, 2004, 17(1): 43-50. Medvedev S P, Khomik S V, Olivier H, et al. Hydrogen Detonation and Fast Deflagration Triggered by a Turbulent Jet of Combustion Products [J]. Shock Waves, 2005, 14(3): 193-203. Sorin R, Zitoun R, Desbordes D. Optimization of the Deflagration to Detonation Transition: Reduction of Length and Time of Transition [J]. Shock Waves, 2006, 15(2): 137-145. Nian W M, Zhou K Y, Wang H L, et al. The Re-intension Process of Gaseous Detonation Downstream of the Acoustic Absorbing Walled Section [J]. Journal of Experimental Mechanics, 2005, 20(1): 37-43. (in Chinese) 年伟民, 周凯元, 王汉良, 等. 气体爆轰波在声学吸收壁下游的再加强过程 [J]. 实验力学, 2005, 20(1): 37-43. Zhu Y J, Yang J M, Lee J H S. High-Speed Deflagration and It's Transition to Detonation in Two Different Gaseous Mixtures [J]. Journal of Experimental Mechanics, 2008, 23(2): 110-117. (in Chinese) 朱雨建, 杨基明, Lee J H S. 两种不同气体中的高速爆燃波及其向爆轰的转变 [J]. 实验力学, 2008, 23(2): 110-117. Sun C W, Wei Y Z, Zhou Z K. Applied Detonation Physics [M]. Beijing: National Defense Industry Press, 2000. 孙承纬, 卫玉章, 周之奎. 应用爆轰物理 [M]. 北京: 国防工业出版社, 2000.
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