网板是拖网的重要属具之一,广泛应用于近岸小型单拖渔船的生产作业中,其水动力性能的优劣直接关系到拖网的生产效果和经济效益。作者以网板面积1 m2、展弦比0.55的V型网板为例进行小型单拖渔船的水动力性能研究。基于田内相似准则,相似比为2制作网板模型,进行循环水槽模型试验,实验冲角在10~60°范围内,来流速度在0.2~0.7 m/s,得出网板升阻力系数等流体动力特性曲线、临界冲角、最大升阻比。结果表明,该型网板的最大升阻比约为1.86,达到最大升阻比的临界冲角在15~25°附近,该结果可为渔业生产操作中网板冲角的设置提供依据。实验结果同时显示,该型网板的水动力效率略低于其他类型网板,说明其板型仍有较大的改进空间。%Otter Board is one of the important trawl accessories. It has been widely used in fishery and has a directly effect on fishery harvesting and economic benefit. In this paper, the hydrodynamic performance of otter board of small trawl vessels has been investigated, taking Vee type otter board as an example, whose area and aspect ratio are 1 m2 and 0.55, respectively. Based on the Tauti law, the model door force under different flow velocity and attack angle was measured. The paper concluded the hydrodynamic characteristic curve of otter board coefficients, critical attack angle and maximum lift-to-drag ratio. The results show that the critical attack angle to achieve the effective expansion is 20°, which has provided a rational relative position of otter board for fishery production.
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