向家坝导流底孔通气孔体型空化特性试验研究  

Experimental study on cavitation characteristics of vent in bottom diversion outlet of Xiangjiaba Hydropower Station

作　　者：陈杨[1] 姜伯乐[1] 杨江宁[1] 

机构地区：[1]长江科学院水力学研究所,湖北武汉430010

出　　处：《人民长江》2014年第12期74-76,96,共4页Yangtze River

基　　金：中央级公益性科研院所基本科研业务费专项资金资助项目(CKSF2012027/SL;CKSF2014043/SL)

摘　　要：在向家坝水电站导流底孔进口顶缘曲线段加设通气孔,可有效改善封堵闸门启闭过程中的流态、脉动压力和启闭力特性,但也可能由此带来空化空蚀问题。加设与否,需要通过减压模型试验予以论证。利用1∶40水力学局部模型,针对导流底孔不设通气孔和设3种不同孔径通气孔体型的空化特性进行了减压模型试验研究。结果表明:不设通气孔时,无蒸汽型空化发生;加设通气孔后,蒸汽型空化达到初生状态或初生阶段,空化强度随通气孔直径增大略有加强,但空蚀破坏的可能性较小。加设2个通气孔(孔径113 cm)体型的方案,已被用于实际工程中,运用效果良好。The setting of vent at the curve segment on entrance top edge of the bottom diversion outlet of Xiangjiaba Hydropower Station can improve flow pattern, fluctuation pressure and characteristics of hoisting force during open-close process of sluice gate, however, it brings cavitation problem as well. The test should be conducted by pressure relief model to verify whether the vent is set or not. By using 1：40 hydrodynamic model, the cavitation characteristics for the vents with 3 different diameters and no vent were studied by the model test. The results show that if no vent is arranged, no steam-type cavitation will occurs;if the vent is set, the steam-type cavitation reaches initial stage and the cavitation intensity increases slightly with the vent diameter, and the possibility of cavitation damage is small. The scheme of setting 2 vents with diameter of 113 cm was applied in practical engineering and good effect was obtained.

关 键 词：导流底孔 通气孔 水下噪声谱级 空化 向家坝水电站 

分 类 号：TV551.13[水利工程—水利水电工程]