Elementary Analysis for Discharge Capacity of Arced Labyrinth Weirs

Document Type : Research Paper


1 Ph.D. Student, Department of Hydraulic Structures, Faculty of Engineering, Urmia University, Urmia, Iran.

2 Assistant Professor, Department of Hydraulic Structures, Faculty of Engineering, Urmia University, Urmia, Iran.


Nonlinear weirs are among the hydraulic structures that, despite their great importance and application, so far, no general method for estimating their discharge capacity has been accomplished. Laboratory or numerical modelling is commonly used to achieve nonlinear weir discharge capacity. It should be noted that employing the design equation from one geometric family of nonlinear weirs to another is impractical. The utilization of numerical or laboratory models in the preliminary stages of the design of these structures is a time and cost-consuming process, which is highlighted by the variety of nonlinear weir geometry. In this research, a general method for estimating the nonlinear weirs discharge capacity is presented. The proposed method analyzes nonlinear weir discharge capacity using energy and discharge equations for discretized solution fields. Furthermore, the local submergence in nonlinear weirs, which has a tangible effect on their discharge capacity, has been corrected. Results of laboratory models performed on the oblique weir, arced labyrinth weir, and Isabella dam weir have been used to evaluate the efficiency of the proposed method. The proposed method with high correlation and accuracy has estimated the discharge capacity of these weirs. The maximum error observed was 12 percent for the oblique weir,15 percent for the arced labyrinth weir, and 15 percent for the Isabella Dam weir.


Main Subjects

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