Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30184
Evolution of Developing Flushing Cone during the Pressurized Flushing in Reservoir Storage

Authors: Meshkati M. E., Dehghani A. A., Naser G., E mamgholizadeh S., Mosaedi A.

Abstract:

Sedimentation in reservoirs and the corresponding loss of storage capacity is one of the most serious problems in dam engineering. Pressurized flushing, a way to remove sediments from the reservoir, is flushing under a pressurized flow condition and nearly constant water level. Pressurized flushing has only local effects around the outlet. Sediment in the vicinity of the outlet openings is scoured and a funnel shaped crater is created. In this study, the temporal development of flushing cone under various hydraulic conditions was studied experimentally. Time variations of parameters such as maximum length and width of flushing and also depth of scouring cone was measured. Results indicated that an increase in flow velocity (and consequently in Froude number) established new hydraulically conditions for flushing mechanism and so a sudden growth was observed in the amount of sediment released and also scouring dimenssions. In addition, a set of nondimensional relationships were identified for temporal variations of flushing scour dimenssions, which can eventuallt be used to estimate the development of flushing cone.

Keywords: Pressure Flushing, Dam, Sediment, Scouring.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1058207

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1569

References:


[1] Olesen, K.W., Basson, G. (2004) "A 2D model for reservoir sedimentation and flushing", Conference of Hydraulics of Dams in Iran.
[2] Shen, H.W. and Lai J.-S. 1996. "Sustain reservoir useful life by flushing sediment". International Journal of Sediment Research. Vol. 11(3): 10- 17.
[3] Brandt, S. A. 2000. "A review of reservoir desiltation". International Journal of Sediment Research. Vol. 15, No. 2. pp. 321-342.
[4] Brown, C.B. 1943. "The Control of Reservoir Silting". United States Department of Agriculture, Miscellaneous Publication No. 521, Washington, D.C. p. 166.
[5] Qian, N. 1982. " Reservoir sedimentation and slope stability; technical and environmental effects". Fourteenth International Congress on Large Dams, Transactions, Rio de Janeiro, Brazil, 3-7 May, Vol. III. pp. 639-90.
[6] White W.R. and Bettess R. 1984, "The feasibility of flushing sediments through reservoirs". Challenges in African Hydrology and Water Resources, Proceeding of Harare Symposium, July, D.E. Walling, S.S.D. Foster, P. wurzel, eds, IAHS Publication No.
[7] Fang D. and Cao S. 1996 An experimental study on scour funnel in front of a sediment flushing outlet of a reservoir. Proceedings of the 6th Federal Interagency SedimentationConference.
[8] Shen H.W., Lai J.S. and Zhao D. 1993, "Hydraulic desiltation for noncohesive sediment". Proceeding of the 1993 Annual ASCE Hydraulic Engineering Conference, San Francisco, H.W Shen, S.T. Su, and F. Wen, eds, pp. 119-124.
[9] Scheuerlein, H., Tritthart M and Nunez Gonzalez F. 2004. "Numerical and physical modeling concerning the removal of sediment deposits from reservoirs". Conference proceeding of Hydraulic of Dams and River Structures, Tehran, Iran.
[10] Emamgholizadeh, S., Samadi H. and Bina M. 2005. "The flushing of the sediment near the powerintakes in the Dez Reservoir". River Basin Management. Italy.
[11] Emamgholizadeh, S., Bina M. Fathimoghadam M. and GHomeyshi M. 2006. "Investigation and Evaluation of the Pressure Flushing Through Storage Reservoir", ARPN Journal of Engineering and Applied Sciences. Vol. 1, No. 4.