Direct Equations for Sequent Depth and Energy Loss of Hydraulic Jump in Low Slope Trapezoidal Channel

Document Type : Research Paper

Authors

1 Faculty Member at University of Gilan, and PhD Student of Hydraulic Structures, Civil Eng. Department, Shahid Bahonar University

2 PhD Student of Hydraulic Structures, Civil Eng. Department, Shahid Bahonar University

3 Professor, Civil Eng. Department, Shahid Bahonar University

Abstract

Design of channels and stilling basins requires knowledge of various elements of hydraulic jump such as discharge, sequent depth, and energy loss. In the case of low slope trapezoidal channel, the solutions of energy and momentum equations involve tedious methods of trial and error. To solve this problem, various methods have evolved in terms of tables, graphs, and nomograms or a set of empirical equations valid only in a specific range. In this study, the energy and momentum equations are first converted to the dimensionless form. Then, nonlinear multiple regression analysis of the data set obtained from numerical solution of equations was used to develop direct explicit empirical equations for post-jump depth and energy loss in a low slope trapezoidal channel. The proposed equations for hydraulic jump elements are of high accuracy and applicable to a wide range of discharge intensity values and initial conditions without any limitations in comparison to other methods attempted so far.

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