Fluid Dynamic Analysis of Drainage Dome and Drainage Tests

• Main Authors: HSU,HSUEH-CHENG, 許學成
• Other Authors: TSAI,GWO-CHUNG
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/4m6652

碩士 === 國立宜蘭大學 === 機械與機電工程學系碩士班 === 107 === In this study, the numerical simulation analysis software ANSYS/Fluent and experimental methods were used to study the drainage efficiency of the drainage dome. The drainage hole is divided into a blank group, a conventional group and a drainage dome group. Drain pipes are available in diameters of 1.5 inches, 2.0 inches and 2.5 inches. The effect of the arrangement of the drain hole and the diameter of the drain pipe on the drainage efficiency will be discussed. The simulation analysis is based on Computational Fluid Dynamics, which simulates the time and drainage rate of drainage when different drainage pipe diameters and different drainage ports are set. The experimental results show that when the water level is lower than a certain height, the vortex will form during the drainage process of no cover group and the traditional group, and the drainage efficiency will drop sharply at this time. There was no vortex in the drainage process of the drainage dome group. The drainage rate in the same stage is higher than the other two groups. Finally, the drainage rate decreased due to insufficient water level. The simulation analysis showed that the final water level of the drain dome group was lower under the same drainage time. The streamline diagram and the vector diagram show that the water flow of the blank group and the conventional group flows into the drainage hole in a tangential manner, and a vortex is generated. The water flowing through the drain cover group flows directly to the drain hole after rectification, which proves that the drain cover can block the formation of vortices. From the velocity profile, the maximum flow velocity in the drain pipe is maintained for a long distance, and the flow velocity of the drain ring inner drain of the drain cover group is large, which proves that the average flow velocity of the drain cover group is faster. It can be seen from the pressure distribution map that the drainage cover group satisfies the siphon drainage phenomenon: the greater the pressure difference, the faster the drainage flow rate. Comparing the experimental and simulation results, the drainage hood group can reduce the drainage time and increase the drainage rate. Both the simulation and the experiment prove that the drainage hood group can improve the overall drainage efficiency.