Abstract:In order to solve the problems of pipe blockage of the sediment laden flow in lowpressure pipe irrigation, a spiral flow waterconveying method was adopted in the lowpressure pipe irrigation. The generatorwas the key device to generate the spiral flow. Through theoretical analysis and experimental exploration, four testing sections were designed in the generator inner aisle and the hydraulic characteristics of the spiral flow in each testing section were studied. The results show that the guide vanes have significant influence on the velocity field and the vorticity field in the generator. In different radial cylinders,the velocity changes greater in the curve segment of the guide vane, and the closer it is to the pipe wall the greater the velocity changes. In the same radial cylinder,the variations of the axial velocity are the largest, while those of the circumferential component take second place and those of the radial component are the smallest. The vortex happens at the entrance to the guide vane. Then the vorticity increases constantly and diffuses to the region without guide vanes. The dense area of the vorticity is formed and at the existing region of guide vanes, and the closer it is to the pipe wall the greater the vorticity changes. Meanwhile, the rotational violent degree was described by the values of Rossby number and Ekman number when the water flow goes through the generator. The Rossby numbers are less than 1 and the magnitudes of Ekman number lie between 10-6 and 10-5 in the vorticity field of the spiral flow in the generator. It shows that the rotational violent degree is greater while the water flow goes through the generator.
李永业, 孙西欢, 王 锐. 起旋器内部的流速场和涡量场特性[J]. 排灌机械工程学报, 2011, 29(2): 155-159.
Li Yongye, Sun Xihuan, Wang Rui. Characteristics of velocity field and vorticity field in generator. Journal of Drainage and Irrigation Machinery Engin, 2011, 29(2): 155-159.
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