葛洲坝过坝水流溶解气体超饱和数值模型研究

葛洲坝工程闸坝泄流促使下游河道水体中溶解气体浓度出现过饱和现象,为深入研究过坝水流溶解气体超饱和机理,建立了葛洲坝过坝水流的流动及溶解气体浓度计算的数学模型,并采用监测数据对模型参数进行率定,并对模型计算的可靠性进行了验证。结果表明:所建的数值模型能够真实描述葛洲坝坝身泄流运动的特点和溶解气体过饱和现象的发生,为进一步研究过坝水流溶解气体超饱和机理奠定基础。

Numerical Model of Dissolved Gas Supersaturation Flow over Spillway of Gezhou Dam Project

High-speed entrained flow and strong collision during the process of energy dissipation in stilling basin will produce large number of air bubbles entrapped into water during high-dam discharge.In order to study dissolved gas supersaturation downstream of the sluicing dam,mathematical models for flow over spillway and dissolved gas concentration are proposed based on the above theoretical consideration to predict the air concentration,velocities and turbulent viscosity distributions of flow through a sluicing structure including a stilling basin and to study the re-aeration of air-entrained flow.The numerical results for the air-entrained flow agree well with experimental data for various conditions.The results show that the mathematical models can accurately simulate the flow characteristics through the sluicing structures,especially the rapid air entrainments into the flow,and can help investigations on the characteristics of flow over spillway and dissolved gas supersaturation.