Abstract: By use of energy equation as well as the pressure momentum conservation equation for the first and second section of conjugate depths as the occurrence of hydraulic jump in the circular culvert, the first and second conjugate depths in the circular culvert of Guanxi reservoir dam under normal operation condition are calculated in the paper. The result shows that the cavitation erosion occurred on the top and side area of the circular culvert is caused by harmful flow pattern. Accordingly, prevention measures are advanced.

Key words: circular culvert, hydraulic jump, cavitation erosion

摘要： 采用能量方程与圆形涵管发生有压水跃时第一、第二共轭水深断面的压力动量和守恒方程，计算了官溪水库坝下涵管正常蓄水位运行工况下的第一、第二共轭水深，指出了坝下涵管顶部及侧壁发生严重蚀损破坏是管内不良流态引发的空化空蚀所致，提出了防空蚀破坏措施。

关键词: 圆形涵管, 水跃, 空化空蚀