三峡船闸输水隧洞反弧门后廊道体型空化模型试验

针对三峡永久船闸的第三级水隧洞反向孤形阀门后顶扩和底扩两种廊道体型进行了恒定流减压状态下的空化模型试验。结果表明：在拟定的若干阀门开度条件下，反孤门底缘均存在不同程度的空化现象，但顶扩体型的空比较扩体型严重，故底扩体型较顶扩体型更具优越性。为此，建议通过控制阀门快速启闭操作方式，增加阀门后淹没水深等措施减免空化强度。

Study on Cavitation Experiment of Gallery Shape Back of Ogee Gate of Lock Water Conveyance Tunnel in Three Gorges

Under steady flow the cavitation experiment of two type gallery shapes both back top and bottom expansion of ogee gate of permanent lock of third water canveyance tunnel in Three Gorges Hydropower Project have been studied. Results showed that different degree cavitations at bottom edge of the ogee gate, with different openings, have been found, but cavitation inception of the top expansion is more serious than that of bottom expansion; so that the cavitation resistant behaviors of the bottom expansion is also better than that of top expansion.For preventing cantation, some measnres, such as controlling cperating method of ogee gate and increasing submergence depth back of gallery and fixing aeration devices etc., have been saggested.