Study on the influence of rigid plant roots and stems on the maximum shearing characteristics of boundary layer under regular wave
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摘要: 基于考虑根茎影响的近岸植物消波实验，对边界层的最大剪切力特性进行了研究。利用前人提出的规则波下含植物水流的边界层流速计算公式，探究了单独根和根茎组合两种植物模型的边界层最大剪切力特性，分析了两种模型的剪切力的沿程变化、植物对剪切力衰减特性的影响，拟合了衰减系数的公式。研究表明，波浪在通过植物带时，剪切力会出现一定幅度增大，随后逐渐降低。植物对剪切力的消减效果随入射波高的增大而增大，且茎有助于根群对边界层最大剪切力的消减作用，其消减系数的范围为0.06~0.61，拟合的公式更加适用于水深较浅的情况。Abstract: The characteristics of the maximum shear force in the boundary layer were studied based on the wave attenuation experiment of nearshore plants considering the influence of roots. The maximum shear force characteristics of the boundary layer under two plant models, root alone and combination of roots and stems, were investigated by using the formula of boundary layer velocity calculation with plant water flow under regular waves proposed by predecessors. The shear force variation along the path and the effect of plants on the shear force attenuation characteristics of the two models were analyzed, and the formulas of the attenuation coefficients were fitted. Studies have shown that when waves pass through the plant zone, the shear force increases to a certain extent and then decreases gradually. The reduction effect of plant on shear force increases with the increase of incident wave height, and the stem contributes to the reduction effect of root group on the maximum shear force of boundary layer, and the reduction coefficient ranges from 0.06 to 0.61. The fitted formula is more suitable for shallow water.
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Key words:
- generalized plant model /
- boundary layer /
- shear force /
- root /
- stem /
- regular wave
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图 4 单独根模型剪切力沿程衰减规律
Fig. 4 The variation of shear force attenuation along the way with roots alone
图 5 根+茎模型影响下的剪切力沿程衰减规律
Fig. 5 The variation of shear force attenuation along the way with roots and stems
图 7 剪切力消减系数与无量纲参数之间的关系
Fig. 7 Relationship between shearing force reduction coefficient and dimensionless parameter
表 1 实验工况
Tab. 1 Expermental cases
水深h/cm 周期T/s 波高H/cm 30.0，35.0 1.0，1.3，1.6，1.9 4.0，6.0，8.0，10.0 
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