Effects of hydraulic structures on pumping sump flows

• Main Authors: Chih-YaoYang, 楊智堯
• Other Authors: Huang-Huei Huang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/02822892667895689261

碩士 === 國立成功大學 === 水利及海洋工程學系碩博士班 === 98 === 　　Large-scale pumps have been extensively used in sewage treatment plants, flood control pumping stations, and circulating cooling water system of electric power plants. The whole system contains lots of complicated hydraulic structures. While designing the sump, the project technical specification such as Unite States Standard (HI) and Britain’s standard (BHRA), etc. are widely consulted at present. However, those project technical specifications are established in ideal simple conditions, while the extra structures increasing, it still has to do the physical modeling test to ensure the security and understand the variation in flow fields. 　　The experimental model of present paper is designed according to the second nuclear power plant of Taiwan. Detailed three-dimensional measurements of the approach flow in the pump sump were obtained by using an Acoustic Doppler Velocimeter(ADV), discussion on uniform and non-uniform flow in front of the suction pipe. The swirl angles at the throat of the suction pipe were also measured by swirl meter to investigate effects of different suction structures and observed the frequency of free surface vortices appearance. Besides, also discussed the relationship between the effects upon baffle wall and it’s place. 　　The experimental results show that the pump-approach flow distributions are stable with uniform flow. The average turbulent intensity with non-uniform flow increased 1.5 to 2 times compared to uniform flow. Generally speaking, turbulent intensity is directly proportional to the distance of suction pipe. The baffle wall performed very well in terms of mitigating the intensity and appearing frequency of free surface, and the best installation place is in the middle of free surface. The suction structure is able to improve the flow condition. The test result is almost no difference to diverse suction structure angles. The about mentioned results would be referred to the important of intake structure in the future.