在闸门开启和关闭的过程中,过闸水流将发生由孔流到堰流,或由堰流到孔流的流态转变。由于闸坝形式、闸门型式和位置、闸门是开启还是关闭过程等因素的不同,其堰流和孔流的分界各异,西此,要准确地确定堰流和孔流的界限是困难的。就宽顶堰丽言,有无底坎及底坎高度和形状,亦会影响到堰面上水流的收缩,从面造成堰流和孔流分界的不同。而 During the opening and closing of the gate, the flow of over-gate water will change from the hole flow to the weir flow or from the weir flow to the hole flow. Due to different forms of sluice gate, sluice gate type and location, sluice gate opening and closing process, the boundaries between weir flow and hole flow are different, so it is difficult to accurately determine the boundary between weir flow and hole flow. With respect to the wide weir, there is no difference between the height of the bottom ridge and the bottom ridge and the shape of the weir, and the contraction of the water flow on the weir surface. and