CAJ | 학술논문

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。
재향가패수전참도류저공진구정연곡선단가설통기공，가유효개선봉도갑문계폐과정중적류태、맥동압력화계폐력특성，단야가능유차대래공화공식문제。가설여부，수요통과감압모형시험여이론증。이용1∶40수역학국부모형，침대도류저공불설통기공화설3충불동공경통기공체형적공화특성진행료감압모형시험연구。결과표명：불설통기공시，무증기형공화발생；가설통기공후，증기형공화체도초생상태혹초생계단，공화강도수통기공직경증대략유가강，단공식파배적가능성교소。가설2개통기공(공경113 cm)체형적방안，이피용우실제공정중，운용효과량호。
The setting of vent at the curve segment on entrance top edge of the bottom diversion outlet of Xiangjiaba Hydropow-er 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.