泄洪洞突扩突跌段空化特性的试验研究

结合九甸峡水利枢纽泄洪洞工程,在常压模型试验的基础上,通过减压模型实验,探讨了光滑壁面及存在多种尺度凸体时,弧形闸门突扩突跌段侧墙在各级水位及各种相似真空度下的空化特性。实验结果表明,侧墙压力分布特性类似于易于发生空化的反弧段,在清水区内空化特性对不平整度比较敏感,而掺气区域对空化噪声有很好的屏蔽作用。

Experimental Study of the Cavitation Characteristics of Sudden Lateral Enlargement and Bottom Drop Section in Spillway Tunnel

In combining with the spillway tunnel of Jiudianxia hydro junction project,and after usual model test,vacuum experiments were conducted to investigate the cavitation characteristics of radial gate region with sudden lateral enlargement and bottom drop.The cavitation characteristics of side wall were explored for both smooth wall and rough wall at different water heads and similar vacuums.The results show that the pressure distributions on the side walls are quite similar with that over the ogee-section of spillway tunnel, where cavitations take place easily.In pure water area,the cavitation characteristics of the side wall are sensitive to the unevenness of surfaces,while in the aerated area,cavitation noises are shielded significantly.