侧壁激波诱导下凹腔燃烧室冷态流场实验观测

Experimental observation of non-reaction flow field based on cavity supersonic combustor on condition of side wall shock wave

在单凹腔燃烧室中引入侧壁激波,为研究燃烧室内部流动特性,采用纳米粒子平面激光散射技术和粒子图像测速技术对全尺寸玻璃燃烧室模型进行流场观测,获得了冷态流场展向和法向的瞬态灰度图及平均速度场。实验结果表明:在远壁面区域,凹腔内部速度与密度都较低;引入侧壁激波后,近壁面区域凹腔与主流的质量与动量交换增强,速度与密度升高;受到侧壁激波影响,燃烧室底壁边界层不再均匀,凹腔中后部产生大规模低速区,具有明显三维特性。

Side wall shock wave was introduced in super：,onic combustor based on cavity. In order to study the internal flow characteristics of the combustor, nano-particle planer laser scattering and particle image velocimetry technologies were employed to observe internal flow field of combustor model made by glass. Gray images and average velocity distributions of non-reaction flow field in side view and top view were caught by experimental facilities. Observation results reveal that： speed and density of fluid inside cavity are low in the region far away from the side wall ; mass and momentum exchange is enhanced in the region near the side wall on condition of side wall shock wave with high speed and density; boundary layer of combustor bottom wall becomes nonuniform due to side wall shock waves, and large scale of low speed region generates at the rear of cavity with obvious three-dimensional characteristics.