双股高速燃气射流在液体中扩展及相互作用的实验研究

设计了多级渐扩形和矩形观察室,借助高速录像系统研究了双股高速燃气流喷入液体中的扩展及相互作用过程.探讨了喷孔直径、喷孔间距、喷射气压等参数变化对射流扩展形态的影响.结果表明:渐扩结构中较大的渐扩尺寸比能抑制射流扩展过程中的不稳定性;喷射压力越大,射流轴向扩展速度越大,射流的不稳定性越强;和矩形结构相比,同样的工况下,渐扩结构射流轴向速度较小,径向速度较大.

Experimental Study on Expansion Process and Interaction of High Speed Twin Combustion-gas Jet in Liquid

The multilevel stepped-wall and rectangular observation chambers are designed.The expansion process and interaction of high-speed twin combustion-gas jet in liquid are studied by means of high speed digital camera system.The influence of nozzle diameter,dual-orifice interval,jet pressure and chamber structure on jet expansion shape has been discussed.The results indicate that a bigger ratio of diameter-to-length can suppress the jet instability in stepped-wall chamber.The higher axial expansion velocity is discovered under the bigger injection pressure,which increases the instability of jet expansion process.Compared with rectangular chamber,the axial expansion velocity is small and radial expansion velocity is big in stepped-wall chamber under the same conditions.