旋流突扩燃烧室中回流区的嵌套结构

本文探讨了一种综合旋流器和钝体结构特点设计的新型旋流室,并对双股同轴中心旋流突扩燃烧室模型进行了冷和热态试验。试验结果揭示了一个新的物理现象,即旋流器造成的旋流室回流区与钝体形成的突扩燃烧室中心回流区嵌套在一起。热态初步试验表明,该现象的存在能提高突扩燃烧室贫、富油工况的燃烧效率. 

EMBEDDED STRUCTURE OF RECIRCULATION ZONES IN COAXIAL DUMP COMBUSTOR WITH INNER SWIRL INLET

The new swirling chamber designed by combining swirlers with bluff bodies is considered in this paper.The cold flowfields in the coaxial dump combustor with inner swirl inlet were measured and investigated by using five-hole probes.It is found that when the flow ratio of the swirling chamber to the outer annular channel decreases and the expansion ability of outer annular flows toward the combustor wall is enhanced,a two-dimensional axisymmetrical central recirculation zone without tangential velocities occurs behind it in the dump combustor in addition to the swirling chamber recirculation zone.Both recirculation zones are embedded in each other.The swirling chamber recirculation zone not only tends to create the central recirculation zone,but also generates the suction which makes the latter bigger and stronger.Experimental results of combustion show that the high combustion efficiency is obtained as the embedded structure exists.