深海网箱结构设计与分析方法

以目前世界最先进深海网箱装备为基础,论述DNV·GL船级社对项目入级审核要求和设计建造难点。研究总体结构强度分析方法、不同的渔网莫里森模拟方法,研究垂向阻尼对结构总强度的影响程度。结果表明网箱结构质量控制非常关键,总强度主要受静态工况影响;垂向阻尼在浅吃水海域影响较小,对深水海域,莫里森模型模拟渔网需继续对比;深海网箱管结构K节点处建造要求高,通常为高应力区,需细化网格计算焊缝节点处SCF(应力集中系数)根据S-N曲线得到热点应力估算疲劳强度及寿命。该项研究可为深海网箱入级、设计研发优化、建造提供一定的工程参考及技术支持。

Structural Design and Analysis of Offshore Cages

Based on the world most advanced offshore cage,this paper discusses the requirements of DNV·GL Classification Society for the project classification and difficulties in the design and construction.The methods for the analysis of the overall strength and the Morrison simulation of different fishing nets are researched to investigate the influence of the vertical damping on the overall structural strength.The results show that the weight control of the cage structure is very critical as the overall strength is mainly influenced by the static operation conditions.It also shows that the vertical damping has little influence on the overall strength in the shallow waters,whereas the Morrison modeling should be further investigated for the simulation of fishing nets in the deep sea.It is of high requirement for the construction of K-joints of the pipe structure of the offshore cage,usually with high stresses.The fatigue strength and the life should be estimated according to the S-N curve based on the stress concentration factors(SCF)at the weld joint that are calculated by the refined mesh.It can provide engineering reference and technical support for the classification,design,research and optimization of the offshore cage.