CAJ | 학술논문

超声速冲击射流在短距、垂直起降飞行器（S/VTOL）以及火箭发射等方面应用广泛，但是伴随着流场与噪声等诸多方面的问题。要研究这一类问题，必先研究这一类超声速流动的波系结构。文章利用彩虹纹影测量系统，对不同距离不同压比的冲击射流进行实验研究，得到了清晰的彩虹纹影实验结果，细致地呈现了冲击射流的波系结构。基于实验结果，对三种不同结构的冲击射流的波系结构进行了详细分析。发现喷嘴与挡板距离较大时，形成的射流结构与自由射流相似，壁面附近的射流区域不明显。随着距离减小，冲击射流出现壁面冲击区附近射流比较剧烈的现象。距离进一步减小时，出现滞止泡等结构，滞止泡的形状与压比相关。此外，实验表明冲击射流形成的马赫盘大小、形状与来流压比相关。
초성속충격사류재단거、수직기강비행기（S/VTOL）이급화전발사등방면응용엄범，단시반수착류장여조성등제다방면적문제。요연구저일류문제，필선연구저일류초성속류동적파계결구。문장이용채홍문영측량계통，대불동거리불동압비적충격사류진행실험연구，득도료청석적채홍문영실험결과，세치지정현료충격사류적파계결구。기우실험결과，대삼충불동결구적충격사류적파계결구진행료상세분석。발현분취여당판거리교대시，형성적사류결구여자유사류상사，벽면부근적사류구역불명현。수착거리감소，충격사류출현벽면충격구부근사류비교극렬적현상。거리진일보감소시，출현체지포등결구，체지포적형상여압비상관。차외，실험표명충격사류형성적마혁반대소、형상여래류압비상관。
Impinging jets widely exist in many engineering fields,such as a short takeoff ver-tical landing (S/VTOL),as well as rocket lunching.It’s important to know the shock wave structure of impinging jets.In a simple rainbow schlieren system,the knife edge in the cut-off plane is replaced by a tricolor filter with a background color center and two colors separated by central band.The direction of the filter can usually be adjusted so that the density gradients in different direction can be examined.The rainbow schlieren apparatus requires no laser source, the optical alignment is simple,and it is tolerant to minor mechanical imperfections and/or vibra-tions.In this paper,the rainbow schlieren method is used in impinging jets experiments at differ-ent range and pressure ratio.Some perfect experimental results are gotten.Three kinds of impin-ging j ets are discussed and found that the size and shape of mach disk are depended on the pres-sure ratio.The result shows that when the distance between nozzle and ground plate is relatively large,the structure of impinging jet is similar to free jet,and the jet district near the ground plate is weakly.As the distance become closer,the jet region near the ground plate becomes stronger and a big stagnation bubble appears in the recirculation flow region at a particular pres-sure ratio.