P. Parsamehr; Davoud Farsadi; A. Hosseinzadeh Dalir
Abstract
Hydraulic jump plays a significant role in dissipation of kinetic energy downstream of hydraulic structures in a stilling basin. In the present research, hydraulic jump characteristics on roughened bed with half cylindrical shape bars and rectangular bed sill on two adverse slopes of 1 and 1.5 % and ...
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Hydraulic jump plays a significant role in dissipation of kinetic energy downstream of hydraulic structures in a stilling basin. In the present research, hydraulic jump characteristics on roughened bed with half cylindrical shape bars and rectangular bed sill on two adverse slopes of 1 and 1.5 % and horizontal bed were investigated. In total 338 experiments were performed for Froude numbers ranging from 4.6 to 7.4. The results indicated that the length of the hydraulic jump on the adverse slope of 1.5% decreased 46% with sill and 49% on rough bed. Also maximum reduction of sequent depth on the adverse slope of 1.5 % with sill and on rough bed was 24.4% and 44%, respectively, compared with the classic jump. Furthermore, application of a continuous sill on adverse slope to stabilize hydraulic jump with decreasing its length will be economical.
A. Masoodi; P. Parsamehr; F. Salmasi; S. Pureskandar
Abstract
Compound broad-crested weir, have a small inner rectangular section for measuring low flows and then, they broaden to a wide rectangular section at higher flow depths. This paper presents data that will be of use in the design of hydraulic structures for flow control and measurement. A series of laboratory ...
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Compound broad-crested weir, have a small inner rectangular section for measuring low flows and then, they broaden to a wide rectangular section at higher flow depths. This paper presents data that will be of use in the design of hydraulic structures for flow control and measurement. A series of laboratory experiments was performed in order to investigate the effects of length of the lower weir crest and step height of broad-crested weirs of rectangular compound cross section on the values of the discharge coefficient. For this purpose, 15 different broad-crested weir models with rectangular compound cross sections for a wide range of discharges tested. Multiple regression equations based on dimensional analysis theory were developed for computing discharge coefficient. The results of compound broad-crested weirs were compared with Genetic programming (GP) and Artificial neural network (ANN) and it was found that the ANN formulation of the problem of solving for the discharge coefficient is less successful than that by GP. The implementation of GP offers another formulation for discharge coefficient.
