﻿ 大洋勘探船月池阻力特性研究
 舰船科学技术  2022, Vol. 44 Issue (19): 32-37    DOI: 10.3404/j.issn.1672-7649.2022.19.007 PDF

1. 江苏科技大学 海洋装备研究院，江苏 镇江 212003;
2. 中国船舶及海洋工程设计研究院，上海 200011

Research on resistance of moonpool of the ocean exploration ship
LI Wen-juan1, TAO Yan-wu1, YANG Wei2, ZHANG Hai-bin2
1. Marine Equipment and Technology Institute, Jiangsu University of Science and Technology, Zhenjiang 212003, China;
2. Marine Design and Research Institute of China, Shanghai 200011, China
Abstract: For ocean exploration ship, considering straight bow and bulbous bow, as well as three moonpool configurations of no-moonpool, bow moonpool and two moonpools, numerical simulation method is used to analyze the total resistance of each type scheme and the resistance increased by moonpool. This paper analyzes the influence of different ship types and moonpool layout schemes about the resistance of ocean exploration ship and explores the law of components of friction resistance and residual resistance with different ship types and moonpools. The conclusions could provide references for the improvement of the resistance of the moonpool for further.
Key words: ocean exploration ship     moonpool     resistance     numerical simulations.
0 引　言

1 计算模型 1.1 模型主尺度

1.2 月池布置及尺寸

 图 1 船型三维图 Fig. 1 3D view of ship shape

 图 2 月池尺寸示意图 Fig. 2 Sizes of moonpools

2 大洋勘探船月池阻力数值模拟及分析 2.1 计算工况

2.2 计算方案

1）计算域及边界条件

2）计算时间步长设置

ITTC (75-03-02-04, 2014) 推荐的计算船舶阻力的时间步长与船舶的航速以及船长有关，计算时间步长取为：

 $\Delta t = 0.005\sim 0.01{{{L_{{\text{PP}}}}} \mathord{\left/ {\vphantom {{{L_{{\text{PP}}}}} V}} \right. } V} 。$ (1)

3）平均阻力提取方法

4）网格收敛性验证

2.3 计算结果 2.3.1 球鼻首船型设计吃水航行阻力

 图 7 球鼻首船型设计吃水阻力曲线 Fig. 7 Resistance curve of bulb bow at designed draft
2.3.2 球鼻首船型压载吃水航行阻力

 图 8 球鼻首船型压载吃水阻力曲线 Fig. 8 Resistance curve of bulb bow at ballast draft
2.3.3 直立首船型设计吃水航行阻力

 图 9 直立首船型设计吃水阻力曲线 Fig. 9 Resistance curve of straight bow at designed draft
2.3.4 直立首船型压载吃水航行阻力

 图 10 直立首船型压载吃水阻力曲线 Fig. 10 Resistance curve of straight bow at ballast draft
2.4 计算结果分析

1）对于相同的月池布置方案的船型，无论是在设计吃水还是在压载吃水状态，球鼻首船型的总阻力均大于直立型船型。设计航速设计吃水状态，球鼻首船型的无月池、单月池和双月池方案的阻力比直立型船型分别大5.4%，6.6%和7.1%；在设计航速压载吃水状态，球鼻首船型的无月池、单月池和双月池方案的阻力比直立型船型分别大8.7%，10.0%和9.8%。两船型的总阻力对比如图11所示。

 图 11 两船型阻力对比 Fig. 11 Comparison of resistance of two different ship types

2）通过对单月池和双月池方案对比发现：在设计吃水状态下单月池和双月池方案的总阻力差别不大，而在压载吃水状态双月池方案总阻力比单月池方案稍大一些。具体来看，设计航速设计吃水状态和压载吃水状态，球鼻型双月池阻力比单月池阻力分别增大3.1%和2.7%，直立型双月池阻力比单月池阻力分别增大3.1%和2.9%。

3）月池形式的变化对阻力的影响主要体现在剩余阻力增加上，另外月池的存在会减小摩擦阻力。

4）吃水状态对月池产生的剩余阻力影响较大，进而影响不同船型的总阻力大小。

 图 12 球鼻首船型月池增阻曲线 Fig. 12 Curve of added resistance of moonpool of bulb bow

 图 13 直立首船型月池增阻曲线 Fig. 13 Curve of added resistance of moonpool of straight bow

3 结　语

1）对于相同的月池布置方案的船型，无论是在设计吃水还是在压载吃水状态，球鼻首船型的总阻力均大于直立型船型。

2）通过对单月池和双月池方案对比发现：在设计吃水状态下单月池和双月池方案的总阻力差别不大，而在压载吃水状态双月池方案总阻力比单月池方案稍大一些。

3）低航速时，月池增阻随航速增加，而航速在上升到一定值附近会出现拐点，月池增阻呈下降或平稳趋势，航速继续增大后，增阻趋势会随吃水及船型的不同而呈现不同的趋势，但无论何种船型或吃水状态，月池的存在导致摩擦增阻为负值，即月池会降低船体的摩擦阻力。双月池方案摩擦阻力减小程度更大一些。

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