摘要： 拖网网板的水动力模型试验结果经常会因雷诺数、模型尺度等各种试验因素出现不同程度的结果偏差。为研究模型参数对拖网网板水动力试验的影响机理，选取立式V型曲面网板为研究对象，基于水槽模型试验结合计算流体力学数值模拟方法，对比分析其水动力性能及流场分布，探究模型尺度比、板面厚度及模型材料等参数对其水动力试验结果的影响。结果显示：模型尺度比变化对网板升/阻力系数曲线形状无显著影响，但模型尺度缩小过多（20:1）将导致升力系数在小冲角（α＜30°）时偏差明显；模型板面厚度增加会导致升力系数在大冲角（α＞30°）下的显著降低，而对阻力系数的影响则主要反映在小冲角（α＜30°）时；非金属材料模型由于刚性不足，在水槽模型试验过程中容易因受力后产生一定位移与变形而引起试验结果的偏差。基于上述结果，设计网板水动力模型试验时，应使得模型尺度尽可能大，减小模型尺度对试验结果精度的影响；可适当增加板面厚度以提高模型结构稳定性，增厚范围不宜超过2倍。
关键词:
网板,
水动力,
模型试验,
影响机理,
数值模拟
Abstract: The hydrodynamic model experiment results of trawling otter board often have different degrees of deviation due to various experimental factors such as Reynolds number and model scale ratio. To understand the Influence mechanism in the hydrodynamic model experiment of otter board, this paper selects vertical cambered V-Type otter board as the research object, bases on the flume tank model experiment combined with computational fluid dynamics (CFD) numerical simulation method, the hydrodynamic performance and flow field distribution were compared and analyzed, aims to explore the influence of model scale ratio, board thickness and model material on its hydrodynamic performance experiment. The results show that the change of model scale ratio has no significant effect on the curve shape of lift coefficient and drag coefficient, but excessive reduction of model scale ratio (20:1) will lead to significant deviation of lift coefficient at the small angle of attack (α < 30°). The change of the board thickness will lead to a significant change of the lift coefficient at the large angle of attack (α > 30°), while the influence on the drag coefficient mainly reflects on the small angle of attack (α < 30°). Non-metallic material model is insufficient rigidity, and it is easy to produce certain displacement and deformation after obtaining stress in the flume tank model experiment process, which will cause the deviation of experimental results. Based on the above results, the model scale should be as large as possible to reduce the influence of model scale on the accuracy of experimental results. The structure stability of the model can be improved by increasing the board thickness, but the thickening range should not be more than double of the prototype.
Key words:
otter board,
hydrodynamic characteristics,
model experiment,
influence mechanism,
numerical simulation
王一博, 初文华[], 张怀志, 曹宇, 崔森琦, 武树龙,. 基于CFD的拖网网板模型参数对水动力试验的影响研究[J]. 渔业现代化, 2023, 50(5): 101-.
WANG Yibo , CHU Wenhua , ZHANG Huaizhi, CAO Yu, CUI Senqi , WU Shulong,. Study on the influence of otter board model parameters on hydrodynamic experiment based on CFD[J]. Fishery Modernization, 2023, 50(5): 101-.