furthermore, the horseshoe shape vortex system occurred to the upstream of the jet exit and the layer structure of vortexes occurred to the wake of the reverse flow region downstream of the jet are also investigated 另外,觀測到射流噴口上流的馬蹄渦系以及射流逆流區(qū)下游尾跡區(qū)旋渦的層狀結(jié)構(gòu)形式。