超声速气流中煤油喷雾的热射流强迫点火  

Forced ignition of kerosene spray in supersonic airflow with hot gas injection

作　　者：席文雄[1] 王振国[1] 李庆[1] 梁剑寒[1] 

机构地区：[1]国防科学技术大学高超声速冲压发动机技术重点实验室,长沙410073

出　　处：《航空动力学报》2012年第11期2436-2441,共6页Journal of Aerospace Power

基　　金：国家自然科学基金(11102230)

摘　　要：在来流马赫数为2、总温为840K的双模态超燃冲压发动机扩张型燃烧室的冷起动工况条件下,对凹腔上游的煤油横向射流喷雾的热射流强迫点火过程进行了试验研究.采用高速相机拍摄了点火过程中的煤油喷雾阴影和自发光火焰的动态发展图像,对比分析了热射流喷射位置和喷射方向对点火试验结果及其凹腔驻留火焰形成的影响.试验结果表明:热射流点火主要以凹腔下游热射流与煤油喷雾的掺混燃烧为主要特征;远场的火焰逆流传播形成凹腔驻留火焰是热射流实现成功点火的主要机制.Forced ignition of kerosene spray with hot gas injection was investigated ex- perimentally in an expanding scramjet combustor with incoming air total temperature of 800 K and Mach number 2 which was related to a typical cold start-up condition of dual-model scramjet. The fuel was injected vertically into the crossflow upstream the flame-holding cav- ity. The kerosene spray shadow and self-luminosity flame evolvement during the process of ignition were observed using high speed camera. The effects of injection scheme such as po- sition and direction of hot jet on the ignition results and cavity-trapped flame generation were compared and analyzed. Results reveal that the enhanced ignition by hot gas injection is characterized by the far-field diffusive burning between spray and hot jet. The trapped flame within cavity is created due to the flame propagation upstream which is the dominant mecha- nism of successful flame establishment.

关 键 词：点火 煤油喷雾 热射流 火焰传播 凹腔驻留火焰 

分 类 号：V233.3[航空宇航科学与技术—航空宇航推进理论与工程]