﻿ 不同型式液舱晃荡压力对比分析
 舰船科学技术  2023, Vol. 45 Issue (12): 27-30    DOI: 10.3404/j.issn.1672-7619.2023.12.005 PDF

Comparative analysis of sloshing pressure for tanks with different types
GUO Jian-jie, WANG Wei, LI Cong, ZHOU Bo, CUI Hai-xin
Marine Design and Research Institute of China, Shanghai 200011, China
Abstract: For liquid cargo ship, tank sloshing is inevitable during navigation. It is very important to adopt a reasonable tank structure to reduce the tank sloshing pressure. Based on the traditional rectangular tank, considering adding horizontal baffles with different widths and numbers on the longitudinal bulkhead and the top cutting, the three-dimensional model of the tank is established, and the sloshing pressure of the three-dimensional tank is calculated by using Fluent software to evaluate the influence of the tank structure on the sloshing pressure. The calculation shows that under high loading rate, the sloshing situation in the cabin can be optimized by reasonably arranging the number and width of baffles, and the sloshing pressure under high loading rate can be effectively reduced by reducing the length of the cabin along the sloshing direction with the one of the top cutting.
Key words: liquid cargo ship     horizontal baffle     top cutting     sloshing pressure
0 引　言

1 液舱方案

2 数值模型 2.1 简化模型

2.2 工况

 图 1 液舱结构优化型式 Fig. 1 Optimized type of tank structure
2.3 横摇运动模拟

3 计算结果及分析 3.1 第1类方案

 图 2 计算网格 Fig. 2 Tank calculation grid

 图 3 压力测点布置图 Fig. 3 Layout of pressure measuring points

 图 4 0.7装载率单挡板测点压力曲线 Fig. 4 Pressure curve of point for 0.7 loading rate with single baffle

 图 5 0.85装载率单挡板测点压力曲线 Fig. 5 Pressure curve of point for 0.85 loading rate with single baffle
3.2 第2类方案

 图 6 0.7装载率各数量挡板测点压力曲线 Fig. 6 Pressure curve of point for 0.7 loading rate with baffle of each quantity
4 结　语

1）在挡板和自由液面相互之间距离不大的情况下，在侧壁上添加水平挡板使舱内特别是液面附近晃荡压力较无挡板时恶劣，导致液面附近的晃荡压力增加1倍以上，且挡板尺寸越大，晃荡情况越恶劣；

2）侧壁水平挡板数量并非越多越好，就0.7装载率2.0 m挡板工况而言，三挡板方案优于单挡板方案及双挡板方案，但双挡板方案对应的晃荡压力反而要大于单挡板方案；

3）当挡板浸没在自由液面以下，且和液面的距离较大时，通过设置合理的挡板数量和宽度，可以使舱内的晃荡情况得到明显改善，建议挡板宽度设置为液舱宽度的0.1～0.15倍；

4）舱顶角隅削斜方案可以减弱晃荡压力，其原因在于舱顶削斜后，液面附近沿晃荡方向的舱室长度会减小，因而顶部削斜方案对高装载率工况液面附近晃荡压力减小效果比较明显，对低装载率工况晃荡压力减小效果不大。高装载率时可以通过减小液面附近的液舱宽度降低液面附近的晃荡压力。

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