船闸输水阀门后底突扩廊道流态特性分析

Unsteady Separated Flow Development in the Abrupt Bottom Expansion Water Filling Tunnel of a Shiplock

高水头船闸输水反弧门开启过程中，阀门后廊道内产生非恒定分离回流与旋涡运动，容易发生水流空化。本文通过二维数值计算，给出了反弧门后底突扩后廊道内流态随阀门开度的变化，分析了小开度平稳变化型、大开度剧烈振荡型与满开度准恒定型三种不同流态的特征与发生、发展机理，比较、分析了阀门后廊道底部突扩体型与顶部渐扩体型水动力特性的异同。

During the gate opening period, unsteady separated flow with complicated eddy motions occurs in the radial gate tunnel of a high rise shiplock, easily resulting in harmful flow cavitation. This paper presents the 2-D numerical modeling results of this type of flow in the radial gate tunnel with abrupt bottom expansion. Three flow regimes are described, the stably varying regime at small gate opening, strongly oscillating regime at greater gate opening, and quasi steady regime at full gate opening. The hydrodynamic mechanism of the flow development is discussed and the flow features between the abrupt bottom expansion and gradual top expansion tunnels are compared.