Document Type : Original Article

Authors

1 Bou-Ali Sina University, Hamedan, Iran

2 Department of Water Engineering, Faculty of Agriculture, University of Ferdowsi, Mashhad, Iran

3 Department of Water engineering, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran

4 Ph. D. Chamran University, Ahvaz, Iran

Abstract

Stilling basin is one of the energy dissipater structures that are used frequently in downstream of hydraulic structures, such as spillways, sluice gates and chutes. The energy dissipation, due to macro-scale turbulence, makes intensive pressure fluctuations so it must be carefully considered when structures are designed. The experiments were carried out in a rectangular flume, 0.3m by 0.4m; and Froude numbers from 3 to 12. The pressure variations data at flume bed and the water level data were recorded by electronic pressure transducer and by piezometers, respectively. The results showed that the intensity of pressure fluctuations in hydraulic jump was related to the Froude number and relative situation from the jump toe. The maximum pressure fluctuation intensity coefficient varied from 0.08 to 0.28 at the distance of 17 to 33 percent of the jump length. The maximum value of was equal to 2 and maximum absolute of coefficient was equal to 1.2 occurred at . Longitude distribution of pressure and its fluctuation and critical values in the length of hydraulic jump also were obtained.

Keywords

Abdul Khader, M. H. and Elango, K. 1974. Turbulent pressure field beneath a hydraulic jump. J. Hydraul. Res. 12(4): 469-489.
 
Akbari, M. E., Mittal, M. K. and Pande, P. K. 1982. Pressure fluctuations on the floor of free and forced hydraulic jumps. Proceedings of the Conference on the Hydraulic Modeling of Civil Engineering Structures. Sep. 22-24. Coventry, England.
 
Bowers, C. E. and Toso. J. W. 1987. Karnafuli project, model studies of spillway damage. J. Hydraul. Eng. 114(5): 469-483.
 
Lopardo, R. A. and Henning, R. E. 1985. Experimental advances on pressure fluctuations beneath hydraulic jumps. Proceedings of the 21st IAHR Congress. Aug. 13-18. Melbourne, Australia.
 
Lopardo, R. A. and Solari, H. G. 1980. Pressure fluctuations beneath free hydraulic jump. Proceedings of the 9th Congress of the Latin American Hydraulica. International Association of Hydraulic Research.
 
 
بررسی تغییرات فشار در بستر حوضچه­های...
Marques, M. G., Drapeau, J. and Verrette, J. L. 1997. Flutuação de pressão em um ressalto hidráulico. Revista Brasileira de Recursos Hídricos Porto Alegre. 2(2): 45-52.
 
Toso, J. and Bowers, E. C. 1988. Extreme pressure in hydraulic jump stilling basin. J. Hydraul. Eng. 114, 829-843.