This experimental study investigated the higher-order velocity moments, turbulence time and length scales, and energy dissipation rates around an intermediately submerged boulder within a wake-interference flow regime in a rock-ramp fish passage. The results show a noticeable variation in the studied parameters in the wake of the boulder, as well as near the bed and boulder crest. The higher-order velocity moments show the presence of infrequent strong ejections downstream of the boulder, which may lead to higher sediment deposition and vertical mixing. The eddy length scales and the volumetric energy dissipation in this experimental model were discussed in relation to fish behavior for both the experimental model and a prototype. Relationships were proposed to roughly estimate integral length scales and energy dissipation rates around the boulder over the flow depth. The findings of this study may improve the design of rock-ramp fish passages considering the effects of turbulence on fish swimming performance and sediment transport.

中文翻译：

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岩石斜坡鱼道中巨石周围的高阶速度矩、湍流尺度和能量耗散率

该实验研究调查了岩石斜坡鱼道中尾流干扰流态内中间浸没的巨石周围的高阶速度矩、湍流时间和长度尺度以及能量耗散率。结果表明，在巨石之后以及床和巨石顶部附近，所研究的参数发生了显着变化。高阶速度矩表明在巨石下游存在罕见的强烈喷射，这可能导致更高的沉积物沉积和垂直混合。讨论了该实验模型中的涡流长度尺度和体积能量耗散与实验模型和原型的鱼类行为的关系。提出了关系来粗略估计沿流动深度的巨石周围的积分长度尺度和能量耗散率。考虑到湍流对鱼类游泳性能和沉积物运输的影响，本研究的结果可能会改进岩石斜坡鱼类通道的设计。