Analysis of Roughness Property of Three Gorges Reservoir in Initial Operation Period
Based on measured sedimentation,daily average inflow and water level series of the Three Gorges Reservoir after 10 years operation,one-dimensional flow model was adopted to calculate sediment deposition roughness of the Three Gorges Reservoir after its actual operation.Results show that the roughness characteristics are different in straight gorge reach,straight stretch reach,bending braided reach in permanent backwater area and in fluctuating backwater area.The roughness are relatively larger and changes little according to the discharge and operation time in straight gorge reach compared with straight stretch reach in permanent backwater area because few sedimentation occurs.The roughness yearly diminished slightly in bending braided reach in permanent backwater area.However in fluctuating backwater area the roughness varied little with the impounding because the river reflects its natural property.With the reservoir operation and sedimentation the roughness generally reduced in the total backwater area with the same discharge and the roughness in the permanent backwater area diminished much more than that in the fluctuating backwater area.Furthermore analysis shows that the change of the transitional period roughness is relative to river location,section shape and channel morphology.The research results lay the foundations for study of the relationship between sedimentation and roughness in Three Gorges Reservoir Region.
Three Gorges Reservoirreservoir sedimentationroughness distributiontransitional period roughness
NETL
NSTL
万方数据
维普
