Experimental Investigation of Natural Frequencies of Gas-Liquid Coupled Systems in Tanks

WEI Zhijun; ZHAI Gangjun; WU Chuijie

doi:10.21656/1000-0887.410207

Volume 42 Issue 2

Feb. 2021

Turn off MathJax

Article Contents

Article Navigation > Applied Mathematics and Mechanics > 2021 > 42(2): 133-141

WEI Zhijun, ZHAI Gangjun, WU Chuijie. Experimental Investigation of Natural Frequencies of Gas-Liquid Coupled Systems in Tanks[J]. Applied Mathematics and Mechanics, 2021, 42(2): 133-141. doi: 10.21656/1000-0887.410207

Citation:

PDF( 2382 KB)

Experimental Investigation of Natural Frequencies of Gas-Liquid Coupled Systems in Tanks

doi: 10.21656/1000-0887.410207

¹State Key Laboratory of Costal and Offshore Engineering(Dalian University of Technology), Dalian, Liaoning 116024, P.R.China;²School of Aeronautics and Astronautics, Dalian University of Technology,Dalian, Liaoning 116024, P.R.China

Funds: The National Natural Science Foundation of China（11602051;51779040）

Received Date: 2020-07-10
Rev Recd Date: 2021-01-04
Publish Date: 2021-02-01

Abstract

Abstract

The wave impact phenomenon widely exists in nature, ocean and aerospace engineering. When the wave impacts on the large-scale structure, the violent free surface may break and the wave tip entraps the air. As a consequence, wave impact with gas-entrapment may cause localized and large load, which may lead to structural failure. During the slamming process, the influence of gas on the natural modes of the free surface has not been systematically reported. A series of experiments were designed and conducted to study the influences of 2 different ullage space pressures on the natural frequencies and damping ratios of gas-liquid coupled systems. High-speed cameras were employed to record the free-surface vibration. Furthermore, the surface wave height was extracted with a self-made image-processing software. The results show that, the sloshing energy mainly concentrates on the lowest natural frequency of the free surface under a low ullage space pressure; while the sloshing energy mainly concentrates on the 2nd natural frequency of the free surface under a high ullage space pressure. As the ullage space pressure of the sloshing tank increases, the dominant natural frequency of the free surface will increase, while the corresponding damping ratio will decrease. Therefore, the gas compressibility is an important factor for the sloshing issue in the tank.
- model test,
- ullage space pressure,
- free-surface elevation,
- natural frequency,
- damping

FullText(HTML)

References(15)

References

[1]	卫志军, 岳前进, 阮诗伦, 等. 矩形液舱晃荡冲击荷载的试验机理研究[J]. 船舶力学, 2012,16(28): 885-892.(WEI Zhijun, YUE Qianjin, RUAN Shilun, et al. Experimental study on sloshing impact load of rectangular liquid tank[J]. Ship Mechanics,2012,16(8): 885-892.(in Chinese))
[2]	卫志军, 岳前进, 张文首, 等. 大尺度储舱液体晃荡砰击压力测量方法研究[J]. 中国科学：物理力学天文学, 2014,44(7): 746-758.(WEI Zhijun, YUE Qianjin, ZHANG Wenshou, et al. Study on the measurement method of liquid sloshing slamming pressure in large scale cabin[J]. Scientia Sinica: physica, Mechanica & Astronomica,2014,44(7): 746-758.(in Chinese))
[3]	WEI Z J, YUE Q J. Experimental investigation of non-similarity slamming phenomena in geometrically similar tanks[J]. International Journal of Offshore and Polar Engineering,2015,25(4): 288-298.
[4]	卫志军, 陈晓东, 董玉山, 等. 两种平台下晃荡冲击荷载的实验研究[J]. 船舶力学, 2015,19(7): 841-849.(WEI Zhijun, CHEN Xiaodong, DONG Yushan, et al. Experimental study on sloshing impact loads on two platforms[J]. Ship Mechanics,2015,19(7): 841-849.(in Chinese))
[5]	王立时, 李遇春, 张皓. 二维晃动自然频率与阻尼比系数的试验识别[J]. 振动与冲击, 2016,35(8): 173-176.(WANG Lishi, LI Yuchun, ZHANG Hao. Experimental identification of two-dimensional sloshing natural frequency and damping ratio coefficient[J]. Journal of Vibration and Shock,2016,35(8): 173-176.(in Chinese))
[6]	DODGE F T. The new dynamic behavior of liquids in moving containers[R]. San Antonio, TX: Southwest Research Institute, 2000.
[7]	吕敬, 李俊峰, 王天舒. 带弹性附件充液矩形贮箱俯仰运动动态响应[J]. 应用数学和力学, 2007,28(3): 317-327.(L Jing, LI Junfeng, WANG Tianshu. Dynamic response of pitching motion of liquid-filled rectangular tank with elastic attachment[J]. Applied Mathematics and Mechanics,2007,28(3): 317-327.(in Chinese)
[8]	LI Y C, WANG Z. An approximate analytical solution of sloshing frequencies for a liquid in various shape aqueducts[J]. Shock and Vibration,2014,11: 672648.
[9]	李遇春, 张皓. 二维晃动模态的统一Ritz计算格式[J]. 振动与冲击, 2014,33(19): 81-85.(LI Yuchun, ZHANG Hao. Unified Ritz calculation scheme for two-dimensional sloshing mode[J]. Journal of Vibration and Shock,2014,33(19): 81-85.(in Chinese))
[10]	蒋梅荣, 任冰, 温鸿杰, 等. 弹性液舱内液体晃荡实验研究[J]. 海洋工程, 2013,31(5): 1-10.(JIANG Meirong, REN Bing, WEN Hongjie, et al. Experimental study on liquid sloshing in elastic liquid tank[J]. The Ocean Engineering,2013,31(5): 1-10.(in Chinese))
[11]	王鹏翔, 李遇春, 王立时. 矩形容器内液体一阶晃动模态试验识别[C]//第26届全国结构工程学术会议论文集(第Ⅱ册). 2017.(WANG Pengxiang, LI Yuchun, WANG Lishi. Experimental identification of 1st-order sloshing mode of liquid in rectangular container[C]// Proceedings of the 26th National Conference on Structural Engineering (Vol Ⅱ) . 2017.(in Chinese))
[12]	HUANG N E, SHEN Z, LONG S R, et al. The empirical mode decomposition and the Hilbert spectrum for nonlinear and non stationary time series analysis[J]. Proceedings of the Royal Society of London,1998,455(1971): 903-995.
[13]	王慧, 刘正士. 一种识别结构模态阻尼比的方法[J]. 农业机器学报, 2008,39(6): 201-202.(WANG Hui, LIU Zhengshi. Method for identifying structural modal damping ratio[J]. Transactions of the Chinese Society for Agricultural Machinery,2008,39(6): 201-202.(in Chinese))
[14]	黄时春. 水下爆炸荷载作用下舰船阻尼特性的试验研究[D]. 硕士学位论文. 哈尔滨: 哈尔滨工程大学, 2016.(HUANG Shichun. Experimental study on the damping characteristics of warship under the action of underwater explosion load[D]. Master Thesis. Harbin: Harbin Engineering University, 2016.(in Chinese))
[15]	付晓波. 经验模态分解法理论研究与应用[D]. 硕士学位论文. 太原: 太原理工大学, 2013.(FU Xiaobo. Theoretical study and application of empirical mode decomposition[D]. Master Thesis. Taiyuan: Taiyuan University of Technology, 2013.(in Chinese))