关键词: 溢流量, 特征线, 阻抗孔, 溢流式调压室

Abstract:

Due to the topography, geological condition and operational pattern, some recent tailrace surge chamber adopts the layout of intersection behind the room, with branch pipes connected at the bottom of chamber. Under this new layout, some new hydraulic problems appear when the units are in stable operation. Taking the method of characteristics (MOC) of one-dimensional rigid water hammer and elastic water hammer as the theoretical basis, we carried out numerical simulation to the tailrace overflow surge chamber shared by two units. The results show that the two impedance holes of the chamber have inward and outward flow under stable operation case, and the flow volume is related with flow in each branch pipe and head loss of each tailrace branches. The surge amplitude in the chamber and the overflow volume increase with the augment of impedance hole size and width of overflow weir.

Key words: overflow surge chamber, characteristic lines, impedance hole, overflow surge chamber