Author(s): Kakeru Takahira; Wang Mingyang; Takashi Nakamura; Tadaharu Ishikawa; Mitsuteru E.; Jamila Tarhouni
Linked Author(s):
Keywords: Reservoir; Sedimentation; Semi-arid area; Fine sediment; Numerical study
Abstract: Wash load sedimentation in semi-arid area during flood events was studied through numerical experiments. Very fine sediment in the Joumine Reservoir, with typical grain size of 5μm, is considered to be eroded from poor vegetation field, where the wet season is from autumn to late spring. The sedimentation process in Joumine Reservoir was investigated by numerical experiments with some assumptions on dynamics of the very fine bed materials. Some estimated meteorological and hydraulic data was used to calculate sediment exchange across the reservoir bed surface. Computation showed the bottom density current was caused by high turbid inflow during large flood period (220m3/s). The current induced re-suspension of bed sediment which accumulated during small and moderate flood period (40m3/s) and transported them to the dam site. The simulation reproduced the distribution of sedimentation during different flood period, demonstrating the potential utility of such models in the management of reservoir sedimentation, suggesting a solution of desilting through reasonable flood discharge.
Year: 2013