摘要
采用k-ε紊流模型对白鹤滩水电站#1泄洪洞竖曲线段及其下游连接段水流流场进行数值模拟,获取了流速、水面线、压强、切应力等水流运动参数分布。结果表明,底板和边墙的压强沿反弧向下游逐渐增大,在反弧后部1/4范围内达到最大,反弧末端的压强梯度大于反弧起始端的压强梯度;切应力沿反弧向下游逐渐增大,且高切应力范围在下斜坡段延伸一段距离,而在同一断面内角隅附近的切应力较大;空化数沿程减小,陡坡段开始需采取掺气减蚀措施,防空蚀的关键部位为反弧段末端后边墙的中下部和底板。
A key problem of high-velocity concave flow through the invert of spillways is the potential of cavitation damage at the flow surface. The flow over the invert of No. 1 spillway tunnel in Baihetan Hydropower Station was studied by numerical simulation. The k--s turbulence model is applied to carry out the numerical simulation. The hydraulic and cavitation properties of the vertical curve flow are obtained. It is found that the piezometric pressure with concave flow increases along the anti-arc segment and reaches the maximum value at the end of the invert. The shear stress also increases along the invert and extends to some distance along the slope downstream. The cavitation index decreases along the vertical curve, so the aerators must be applied successfully in the spillway tunnel. And the sufficient quantities of air should be entrained into the water nearby the lower parts of the sidewalls and the bottom surface downstream of the invert.
出处
《水电能源科学》
2008年第6期108-111,131,共5页
Water Resources and Power
关键词
水力学
泄洪洞
反弧段
数值模拟
hydraulics
spillway tunnel
invert
numerical Simulation
