Air Bubble Entrainment and Gas Transfer at Hydraulic Jumps

摘要

In open channels, the transition from a rapid to fluvial flow is called ahydraulic jump. It is characterized by large scale turbulence, air bubble entrainment and energy dissipation. The authors have investigated the air bubble entrainment at hydraulic jumps with partially developed inflow conditions. The air-water flow is characterized by a turbulent shear region with a large air content which contributes to the enhancement of the air-water interface area and air-water gas transfer in the hydraulic jump. Further a new gas transfer model is presented. Based upon physical evidence, the model enables to predict the dissolved gas contents and water quality downstream of hydraulic jumps with partially developed inflows.