模拟渔获物重量对网囊水动力和振荡特性的影响  

Effects of the simulated catch weight on the hydrodynamic and oscillation characteristics of the codend

作　　者：唐浩[1,2,3,4,5] 张锋 刘伟 叶旭昌[1,2] 胡夫祥[6] 许柳雄[1,2,3,4,5] TANG Hao;ZHANG Feng;LIU Wei;YE Xuchang;HU Fuxiang;XU Liuxiong(College of Marine Living Resource Sciences and Management,Shanghai Ocean University,Shanghai 201306,China;National Engineering Research Center for Oceanic Fisheries,Shanghai Ocean University,Shanghai 201306,China;Key Laboratory of Oceanic Fisheries Exploration,Ministry of Agriculture and Rural Affairs,Shanghai Ocean University,Shanghai 201306,China;Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources,Ministry of Education,Shanghai Ocean University,Shanghai 201306,China;Scientific Observing and Experimental Station of Oceanic Fishery Resources,Ministry of Agriculture and Rural Affairs,Shanghai Ocean University,Shanghai 201306,China;Faculty of Marine Science,Tokyo University of Marine Science and Technology,Tokyo 108-8477,Japan)

机构地区：[1]上海海洋大学海洋生物资源与管理学院,上海201306 [2]上海海洋大学,国家远洋渔业工程技术研究中心,上海201306 [3]上海海洋大学,农业农村部大洋渔业开发重点实验室,上海201306 [4]上海海洋大学,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 [5]上海海洋大学,农业农村部大洋渔业资源环境科学观测实验站,上海201306 [6]东京海洋大学海洋科学学院,东京108-8477

出　　处：《水产学报》2025年第5期183-195,共13页Journal of Fisheries of China

基　　金：国家自然科学基金(32373187);上海市自然科学基金(23ZR1427000)。

摘　　要：【目的】为了更好地了解中层拖网网囊的水动力特性和囊内渔获物重量变化之间的关系。【方法】实验通过动水槽模型探究4种不同重量渔获物(渔获物重量0.00 kg、渔获物重量1.68 kg、渔获物重量3.36 kg和渔获物重量5.04kg)分别在流速0.5、0.6、0.7、0.8和0.9 m/s共5种状态下对网囊稳定性、阻力、形态和体积的影响效果。【结果】(1)网囊结构水阻力随着渔获物重量的增加而增大,随着流速的增大而增大,其中在低流速时,模拟渔获物重量每增加1倍(1.68kg),其网囊水阻力增加值约为空网的30%。(2)网囊结构形状随着流速的增大呈逐渐收紧趋势,而随着渔获物重量的增加,网囊结构充盈,并造成导鱼区收紧,呈“腰鼓”形状。(3)网囊体积与渔获物的大小成正比,当渔获物重量增加到5.04 kg时,网囊体积约为空网时的0.8倍。本研究发现,网囊水阻力与模拟渔获物重量呈正相关关系;空网时网囊体积最大,而随着渔获物重量的增加网囊体积减小。存在模拟渔获物的网囊,无论纵向位移还是阻力都存在明显波动现象。采用3级傅里叶级数拟合网囊纵向位移振荡,拟合效果较好。【结论】本研究可为优化网囊结构、提高网囊水动力和形态特性,改善网囊选择性提供基础科学数据。To investigate the relationship between hydrodynamic characteristics and catch weight inside the mid-water trawl codend,this study examined the effects of catch weights(0.00,1.68,3.36 and 5.04 kg)on the drag force,shape,and oscillation of codend under five different flow velocities(0.5,0.6,0.7,0.8 and 0.9 m/s)using flume tank experiment.The results show that:①the drag force of the codend increased with increasing flow velocity and catch weight.At lower flow velocities,the drag force of the codend with a catch weight of 1.68 kg was 30%greater than that of empty codend;②the shape of the codend structure tended to constrict with increasing flow velocity,while it expanded with increasing catch weight.However,the fish guiding area tightened and took on a"waist drum";③the codend volume was directly proportional to the catch weight.When the catch weight increased to 5.04 kg,the codend volume was approximately 0.8 times that of the empty codend,indicating that the empty codend has the greatest volume.Under different catch weight,the periodicity and the amplitude of codend position oscillations decreased with increasing flow velocity.The codend position oscillations were fitted using a third-order Fourier series,yielding satisfactory results.These findings are expected to contribute to the optimization of the codend structure and provide relevant information for improving the hydrodynamic characteristics,geometric shape,and selectivity of the mid-water trawl codend.

关 键 词：网囊 阻力特性 振荡特性 渔获物重量 形态 

分 类 号：S972.13[农业科学—捕捞与储运]