基于模型试验的定置底刺网作业形态影响因素研究  

On the influential factors in the operation form of bottom-set gillnet based on model tests

作　　者：郭绍健 徐子沐 叶旭昌[1,2,3] 张健 王禹程[1] 周成 GUO Shaojian;XU Zimu;YE Xuchang;ZHANG Jian;WANG Yucheng;ZHOU Cheng(College of Marine Sciences,Shanghai Ocean University,Shanghai201306,China;National EngineeringResearch Center for Oceanic Fisheries,Shanghai201306,China;Key Laboratory of Sustainable Exploitationof Oceanic Fisheries Resources,Ministry of Education,Shanghai201306,China)

机构地区：[1]上海海洋大学海洋科学学院,上海201306 [2]国家远洋渔业工程技术研究中心,上海201306 [3]大洋渔业资源可持续开发省部共建教育部重点实验室,上海201306

出　　处：《海洋渔业》2023年第2期214-226,共13页Marine Fisheries

基　　金：国家重点研发计划(2019YFD0901502,2020YFD0901202);上海海洋大学科技发展专项基金项目(A2-2006-22-200208)。

摘　　要：为了解刺网作业过程中的水动力行为和形态变化,通过聚乙烯(PE)和聚酰胺(PA)刺网在均匀恒定流场中进行水动力学试验,探究了流速、线面积系数和转向网目(T90)对定置底刺网作业高度和形态特征的影响,并提出了两种材料刺网的形变程度(k)拟合公式。研究结果表明,刺网作业高度与流速负相关,流速为0.2、0.4、0.6、0.8 m·s^(-1)时,刺网作业高度分别为静水状态下高度的96.5%、69.3%、43.9%、29.9%,刺网下半部分网目缩结角随流速增大而增大;同一流速时,两种材料刺网作业高度基本一致,但PA刺网网目扩张形态更均匀;低流速时(≤0.2 m·s^(-1)),T0刺网作业高度高于T90刺网,流速达到0.4 m·s^(-1)后,T90刺网作业高度更大;线面积系数是影响刺网形态特征的重要因素,线面积系数越小,刺网作业高度越高,网目扩张形态越均匀。Bottomset gillnet has the characteristics of harvesting a variety of species,high economic benefits,high sizeselectivity and poor speciesselectivity.The hydrodynamic behavior of bottomset gillnet under fishing operation are dynamically changed in response to combined effects of external forces from wave and current,and catch impact etc.,which results in reduced fishing efficiency,fishing gear selectivity and security,and subsequently the remnant netting forms“ghost fishing”.The main internal factors affecting the fishing efficiency and selectivity of gillnet gear include mesh and twine size,working height of gillnet,twine material and hanging ratio,In addition,in the working process,due to the influence of external forces such as waves and streams and the interaction with fish behavior,the form and structure of gillnets change,fishing performance decreases,and selectivity changes.For the intention of further understanding the hydrodynamic behavior and geometry deformation under fishing operation,this study,on the basis of hydrodynamic experiment of polyethylene(PE)and nylon(PA)gillnets in the uniform current,investigated the effect of current velocity,solidity ratio and 90°turned mesh on the working height and shape characteristics of bottomget gillnet,and developed the empirical formulas of deformation degree(k)of PE and PA gillnets.The results showed that the working height of gillnet was negatively correlated with the current velocity,and 96.5%,69.3%,43.9%and 29.9%of the initial height under the still water were achieved under current velocity of 0.2,0.4,0.6,0.8 m·s^(-1),respectively;hanging angle in the lowerhalf part of the gillnet increased with the current velocity.When V=0 m·s^(-1),the gillnet was stretched vertically in the water,the gillnet mesh was in the form of a high middle and low on both sides,the headline was inverted catenatelike.With the increase of current velocity,the gillnet gradually shifted backwards and downwards,the projection area of the gillnet in the Y-Z pl

关 键 词：定置底刺网 模型试验 线面积系数 水动力学 

分 类 号：S972[农业科学—捕捞与储运]