Submerged gas jet plays a very important role in many industries occasion. It often causes load of pool structure induced by flow oscillation. Exploring the mechanism and key influencing factors of submerged non-condensable gas jet oscillation characteristics is of great significance to ensure the safe operation of the equipment. In the present work, the phenomenon of flow oscillation for non-condensable gas jet through a horizontal one- or multi-hole sparger from sonic to supersonic zone is studied experimentally. The steady and unsteady characteristic of flow process and flow structure are visualized by using high-speed camera, and pressure oscillation is obtained by simultaneous pressure measurement. Experimental results show that gas Froude number and sparger structure have great influence on the gas flow pattern. With Froude number increasing, gas flow pattern is obviously reinforced. Multi-hole sparger significantly weakens the gas jet behavior at horizontal direction away from holes comparing with one-hole sparger under the same Froude number. The spectrogram approaches of pressure oscillation indicates the dynamic pressure data contains two principal frequency components. First dominant frequency is identical with that of transient interfacial fluctuation, which is related to gas jet periodic expansion feedback and independent on Froude number and position. And second dominant frequency is not changed with the position, but decreases significantly with the increase of Froude number. Intensity of pressure oscillation increases with Froude number increasing and the distance from sparger decreasing. In addition, the multi-hole sparger can significantly reduce intensity of pressure oscillation under the same Froude number. Dimensionless relation is developed to evaluate the Froude number and sparger structure on the second dominant frequency and intensity of pressure oscillation. This study can be applied to well understanding of flow oscillation mechanism and provide technical support for looking for mitigation measures to reduce oscillation in the future.

潜入式气体射流在许多行业场合中发挥着非常重要的作用。常引起流动振荡引起的池结构载荷。探索水下不凝气射流振荡特性的机理及关键影响因素，对保证设备安全运行具有重要意义。在目前的工作中，不凝气体射流通过水平单孔或多孔分布器从音速区到超音速区的流动振荡现象进行了实验研究。利用高速摄像机对流动过程和流动结构的稳态和非稳态特性进行可视化，并通过同步压力测量获得压力振荡。实验结果表明，气体弗劳德数和分布器结构对气体流动模式有很大影响。随着弗劳德数的增加，气流模式明显加强。在相同弗劳德数下，与单孔分布器相比，多孔分布器显着减弱了远离孔的水平方向的气体射流行为。压力振荡的谱图方法表明动态压力数据包含两个主要频率分量。第一主频与瞬态界面涨落相同，与气体射流周期膨胀反馈有关，与弗劳德数和位置无关。而第二主频不随位置变化，而是随着弗劳德数的增加而显着降低。压力振荡的强度随着弗劳德数的增加和与分布器的距离的减小而增加。此外，在相同的弗劳德数下，多孔分布器可以显着降低压力振荡的强度。建立了无量纲关系来评估弗劳德数和分布器结构对压力振荡的第二主频率和强度的影响。本研究可用于深入了解流动振荡机制，为今后寻找减缓振荡的缓解措施提供技术支持。