Building a chute aerator is an efficient way of protecting the chute bottom from cavitation damage in large flood-discharging hydraulic structures, but it sometimes fails to provide sufficient protection to the side-walls. In this study, basic air–water flow properties were investigated for discharge flows over an offset chute aerator model, with particular focus on the near-bottom and near-wall regions, for a range of discharge velocities over the offset brink (3.58 m/s < V < 8.02 m/s), Froude numbers (4.8 < Fr < 12.0) and Reynolds numbers (8.0 × 10⁴ < Re < 9.2 × 10⁵). The results indicated little transverse variations in air–water flow properties except near the jet impact perimeter. The bottom air concentration and bubble frequency decreased at different rates downstream of the impact point; the influence of Reynolds number on the bubble size and density should not be ignored. The shape of the clear-water core between the upper and lower aeration layers was identified with the aid of high-speed imaging and air concentration calibration against the wall. A formula to predict narrowing of the jet core until its end position was developed.

中文翻译：

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泄洪槽偏置曝气机底部和侧壁曝气性能

在大型泄洪水工建筑物中，设置溜槽曝气机是保护溜槽底部免受空化破坏的有效方法，但有时无法对侧壁提供足够的保护。在这项研究中，研究了偏置滑槽曝气机模型上排出流的基本空气-水流特性，特别关注近底部和近壁区域，针对偏置边缘上的一系列排出速度（3.58 m/ s <  V  < 8.02 m/s)、弗劳德数 (4.8 < Fr < 12.0) 和雷诺数 (8.0 × 10 ⁴  < Re < 9.2 × 10 ⁵ )。结果表明，除了射流冲击周边以外，空气-水流特性的横向变化很小。撞击点下游底部空气浓度和气泡频率以不同速率下降；雷诺数对气泡尺寸和密度的影响不容忽视。借助高速成像和壁面空气浓度校准，确定了上下通气层之间的清水核心的形状。开发了一个预测射流核心变窄直至其最终位置的公式。