Showing 2 results for M. Bina
A. Moradi Sabz Koohi, S. S.m. Kashefipour, M. Bina,
Volume 15, Issue 56 (sumer 2011)
Abstract
Drops are the most important and common hydraulic structures used as energy dissipators in irrigation networks and erodible waterways. Dissipation of energy occurs in two different ways. One portion belongs to the geometric form of the structure (briefly called loss due to structure), whereas the other occurs due to happening of hydraulic jump downstream of the structure. The dimensions of drop structure and downstream stilling basin can be optimized if geometric and hydraulic characteristics are recognized properly. In this research, the effects of drop geometry and hydraulic characteristics on the loss due to structure were investigated. At first, the effective dimensionless parameters were specified. 14 physical models of more common drops including straight, inclined and stepped drops were then built in 2 heights of 51.5 & 25.5 centimeters and 2 bed slopes of 26.6 & 33.7 degrees. The number of steps in stepped models was chosen equal to 3 and 7. With establishment of 90 flow rate, the energy losses were compared. The results showed that in the range of variable parameters, the straight drop has the maximum amount of energy dissipation.
S.b. Sarvarinezhad, M. Bina, A. Moradi, H. Golayj,
Volume 17, Issue 63 (Spring 2013)
Abstract
Rubber dam body is a lying cylinder that lies in the width of channels, rivers and weir crests and is filled with water or air or a combination of both. Shape of this structure is one of the obvious features that does not change in the path of rivers or dam spillways. Rubber dams may be with or without deflectors. Deflector is a triangular or rectangular fin that is installed down the stream of the dam. The purpose of installing a deflector is separating the water from the rubber dam body and avoiding the reattachment between the water and dam body. In this study, four Physical models of rubber dams and deflectors were made at height and ratio of h/p=0.05 in 2 triangular and rectangular shapes and 25 cm length. Experiments were carried out in three different angles (30-45-60). After all the analyses and experiments were done according to the water napes profile and their lengths, it was observed that the 45 degree is more suitable than 30 and 60 degrees. In addition, experimental data and presented equation in this study were compared with the past equations, the results of which were close, showing the validity of the experiments and equations
