圆柱壳下气泡脉动与射流试验特性研究

吴凯伦¹，于福临^1,2*，安展逸¹，鲍永瑞¹，王志鹏¹

1.山东交通学院船舶与港口工程学院，山东 威海  264209；2.威海市流固耦合动力学重点实验室，山东 威海  264209

摘要：为研究水下爆炸气泡在圆柱壳结构下的动力学特征，设计一种圆柱壳下气泡脉动与射流试验系统。通过电火花生成装置产生气泡，采用高速摄影机捕捉气泡动力学特征图像，采用压力传感器采集圆柱壳底部壁面压力载荷变化数据，分析无量纲参数γ对气泡载荷峰值压力及持续时间的影响。试验结果表明：1）当γ为0.25、0.50时，气泡外形为倒蘑菇状-云团状；当γ为0.75、1.00时，气泡外形为柱状-云团状；当γ为1.25、1.50时，气泡外形表现为鸡蛋状-扇状。2）0.25≤γ≤1.50时，气泡冲击波载荷峰值压力随γ的增大而减小，冲击波载荷峰值压力持续时间随γ的增大而增大；气泡第一周期脉动和射流载荷峰值压力持续时间大于第二周期。3）0.25≤γ≤0.75时，气泡第一周期和第二周期脉动和射流载荷峰值压力均随γ的增大而减小。4）0.75＜γ≤1.00时，气泡第一周期和第二周期脉动和射流载荷峰值压力均随γ的增大而增大。5）1.00＜γ≤1.50时，气泡第一周期脉动和射流载荷峰值压力随γ的增大而减小，第二周期脉动和射流载荷峰值压力随γ的增大而缓慢增大。

关键词：水下爆炸；气泡；脉动；射流；圆柱壳

Experimental characteristic study on bubble pulsation and jet under cylindrical shell

WU Kailun¹, YU Fulin^1,2*, AN Zhanyi¹, BAO Yongrui¹, WANG Zhipeng¹

1. Naval Architecture and Port Engineering College, Shandong Jiaotong University, Weihai 264209, China;

2. Weihai Key Laboratory of Fluid-Structure Coupling Dynamics, Weihai 264209, China

Abstract: To investigate the dynamic characteristics of underwater explosion bubbles under cylindrical shell structure, an experimental system for bubble pulsation and jet under cylindrical shell is designed. Bubbles are generated using an electric spark generation device, and bubble dynamic characteristic images are captured by a high-speed camera. Pressure sensors are employed to collect data on pressure load variations at the bottom wall of the cylindrical shell, and the influence of the dimensionless parameter γ on the peak pressure and duration of bubble loads are analyzed. Experimental results indicate that when γ is 0.25 and 0.50, the bubble shape is inverted mushroom-shaped to cumulous-shaped; when γ is 0.75 and 1.00, the bubble shape is columnar to cumulous-shaped; when γ is 1.25 and 1.50, the bubble shape exhibits egg-shaped to fan-shaped morphology. For 0.25≤γ≤1.50, the peak pressure of bubble shock wave load decreases with increasing γ, while the duration of shock wave load peak pressure increases with increasing γ; the duration of peak pressure from the first-cycle pulsation and jet load is greater than that of the second-cycle pulsation and jet load. For 0.25≤γ≤0.75, the peak pressures of both first-cycle and second-cycle pulsation and jet loads decrease with increasing γ; for 0.75＜γ≤1.00, the peak pressures of both first-cycle and second-cycle pulsation and jet loads increase with increasing γ; for 1.00＜γ≤1.50, the peak pressure of first-cycle pulsation and jet load decreases with increasing γ, while the peak pressure of second-cycle pulsation and jet load increases slowly with increasing γ.

Keywords: underwater explosion; bubble; pulsation; jet; cylindrical shell