虹吸进水口的最大真空值过大,水流中会产生蒸汽泡,导致虹吸不能正常工作,甚至引起水流断裂或空穴现象,故最大真空值应予以限制,成为确定进水口喉道顶壁和底部高程的依据,也是控制最大流量的依据。通过国内虹吸进水口的实践和若干较可信的研究成果出发,探讨最大真空值的近似计算及其容许值,以求节省投资,且使设计偏于安全及运行可靠。图2幅,表3个。 Siphon inlet maximum vacuum value is too large, the water flow will produce steam bubbles, resulting in siphon can not work properly, and even cause water flow fracture or hole phenomenon, so the maximum vacuum value should be limited to determine the inlet throat wall and the bottom The basis of the elevation, but also the basis for controlling the maximum flow. Based on the practice of siphon inlet in China and some credible research results, the approximate calculation of maximum vacuum value and its allowable value are discussed in order to save investment and make the design safer and more reliable. Figure 2, Table 3.