响水涧抽水蓄能电站引、尾水道上弯段弯道效应分析

分析研究响水涧抽水蓄能电站引水道、尾水道上弯段水力特性,明确其弯道效应主要表现形式为:门井边垂线流速大于或接近中垂线流速;中垂线流速分布呈轻微扭曲状;沿弯道(段)横断面圆周测压管水头不等于常数。试验表明:上弯段与门井间距离在5倍管径左右可以基本消除弯道效应对流速分布的影响,在7倍管径左右可以基本消除弯道效应对压力分布的影响。

Bend effect of upper bend sections of headrace and tailrace conduits of Xiangshuijian Pumped Storage Power Station

Hydraulic characteristics of the upper bend sections of headrace and tailrace conduits of Xiangshuijian Pumped Storage Power Station were studied.The bend effect was revealed:(1) the mean flow velocities of vertical lines at both sides of gate shafts were nearly equal to or larger than those of vertical line in the center of gate shafts;(2) the velocity distribution of vertical lines in the center was slightly distorted;(3) the piezometric head was not a constant along the circumference of cross section at the bend sections.The model test results indicate that the influences of the bend effect on the velocity distribution can be avoided when the distance between the bend section and the gate shaft is about five times the conduit diameter,and those of the bend effect on the pressure distribution can be avoided when the distance is about seven times the diameter.