【摘要】 <正> 一、前言泄洪管道或泄洪隧洞是水利枢纽的重要建筑物。在泄洪管道或泄洪洞内,当闸门局部开启时,闸门后的空气被高水头作用下的高速水流带向下游,在通气不足的情况下,闸门后的压强可能低于水的气化压强,从而引起闸门和管道的空蚀和振动,严重的还会导致建筑物的破坏。为了保障泄洪管道的安更多还原

【Abstract】 Synopsis The problem of air demand in high-head gated conduits for flood control deals with the simultaneous movements of water and air which are influenced by both hydraulic factors and structural arrangement factors. Taking Froude number at gate-opening, Frgatc, as an independent variable, the ratio of water discharge to the total discharges of water and air flows, Q_w/（Q_w+Q₃）=1/（1+β）, as dependent variable, and parameters S and L/h which reflect the effects of the structural arrangement factors, this paper analyzed the prototype data collected from 18 projects containing 21 gates and 364 data points. The prototype law of air demands is revealed. The empirical carves have been fitted with computers and a new set of empirical formulas has been established. The formulas presented here demonstrate that alr-water ratio β=k（Frgate-1）^M+C, where M is not a constant as generally adopted. but a function of Frgate. for a specified type of structural arrangement of gates and a specified ratio L/h.更多还原