Proposing a Discharge Coefficient Equation for Triangular Labyrinth Spillways Based on Laboratory Studies

Document Type : Research Paper


Department of Water Science and Engineering, Faculty of Agriculture, Bu-Ali Sina University, Hamadan, Iran.


Labyrinth spillways are considered as suitable and economic structures because, firstly, their discharge flow rate, under low hydraulic heads, is high, and secondly, they occupy less space. The flow over these spillways is three-dimensional and is influenced by several parameters. This study endeavors to offer a new equation for the calculation of the discharge flow of triangular labyrinth spillways by using the Buckingham Theory, Genetic Algorithm, the equations offered by other researchers and non-dimensional laboratory parameters. To do so, several experiments were carried out in the hydraulic laboratory of the Department of water science at BuAli Sina University in Hamedan. These experiments were done on triangular labyrinth spillways in a straight condition in certain flumes which were 10 meters long, 0.83 meters wide, and 0.5 meters height. To verify the recommended equation, the authors used the information related to the labyrinth spillway design of Bartletts Ferry dam in the US and the equation for triangular spillways suggested by previous researcher. The results indicated that the equation recommended in this study is far more accurate than the previous one.


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