脉冲爆震燃烧器混合室研究

Experimental investigation on the mixing chamber in pulse detonation chamber

利用CFD程序分别对切向、轴向和径向供气方式的混合室中油、气的混合特性进行了三维数值模拟。切向进气有助于油气的充分混合,但是油、气分布不均;轴向进气时油、气分布比较均匀,但是油气的混合不够充分;而径向进气的油气分布、混合程度介于切向与轴向进气之间,能耗较大。设计了四种混合室结构,进行了基于两相无阀脉冲爆震燃烧器(PDC)的热态试验研究,找到了利于点火、起爆迅速的混合室结构。

Detonation has received much attention lately and been widely explored to its propulsion application. However, there are many unresolved issues related to the applications of detonation combustion, for example the mixing of fuel with air, especially the liquid fuel. This paper focused on the mixing chamber opti- mization based on pulse detonation chamber （PDC）. The mixing characteristic inside a mixing chamber was obtained by three-dimensional simulation. The simulation results indicate that well mixing but uneven concentration distribution occurred when air was introduced through the tangential inlets, while bad mixing but well- proportioned distribution occurred when air was introduced through the axial inlets. The mixing degree and gasoline-air distribution performance when air was introduced through the radial inlets were between that of tangential air flow and axial air flow, and the system energy loss was the largest. According to the above results and the experimental experience, four mixing chambers were designed. In order to observe the effects of mixing chambers on ignition-detonation performance of PDC the proof of-principle experiments of PDC were carried out. The results indicate that the fourth mixing chamber with double orifice plate offered the best ignition-detonation performance.