Abstract:Taking Yanziya hydropower station as an example, the water and sediment motion law of sediment drainage funnel was simulated by using volume of fluid(VOF)model, Reynolds stress model(RSM), discrete N-S equations, and fifth-order Runge-Kutta variable step integration method, and the rationality of mathematical model predictions is demonstrated through physical model test. The results show that the tangential velocity of the sediment drainage funnel is generally small in the middle and large at both ends. The air funnel is generated in the bottom of the sediment drainage funnel, and a forced eddy current is generated around the air funnel. The radial velocity magnitude is small at first and then gets large with increasing radius, and the velocity direction is from the inside to the outside. There is an inward and larger radial velocity in the bottom of the sediment drainage funnel. The axial velocity magnitude is in oscillation, but its amplitude reduces with increasing radius. A top-low and bottom-high vertical distribution of sediment concentration is exhibited, a higher sediment content is found near the bottom, resulting in a higher sediment flow near the bottom. Under constraint of the funnel circular side wall, the water body generates a forced eddy with a strong sediment discharge capacity. The eddy can bring the sediment near the sand discharging bottom hole into the hole quickly, then the sediment was discharged downstream via a sand discharge tunnel connected with the hole. The differences of the predicted tangential, axial, radial velocities, and sediment content from the counterparts in model test are small.
洪振国*,田辉. 水电站排沙漏斗水沙运动规律[J]. 排灌机械工程学报, 2021, 39(3): 251-256.
HONG Zhenguo*,TIAN Hui. Water and sediment motion law of sediment drainage funnel in hydropower station. Journal of Drainage and Irrigation Machinery Engin, 2021, 39(3): 251-256.