Geometric Optimization of labyrinth spillways and Improvement of Hydraulic Performance Using Gray Wolf Algorithm

In this research, optimal design of trapezoidal labyrinth spillway has been investigated using Gray Wolf Optimization (GWO) algorithm with respect to hydraulic conditions. By choosing the assumed volume of spillway concrete as the objective function, after several running the model and trial & error, parameters of the algorithm such as iteration, number of wolves and the penalty coefficient were determined to be 1000, 30 and 〖10〗^11, respectively and by five times of testing, at the 996th iteration, the optimal response of objective function was achieved. The obtained value from the proposed algorithm was compared to the real value and also the results of the Cuckoo Search (CS) algorithm, Genetic Algorithm (GA) and Differential Evolution (DE) in previous studies. Using GWO algorithm for designing the considered dam's spillway, made reduction of 40.928% in amount of assumed concrete volume and increase the rate of discharge to 10.71% than to real value, which showed a better performance compared to above algorithms. Significant reduction of the consumed concrete volume in the proposed spillway by using GWO algorithm indicates ability and necessity of using this algorithm to solve optimization problems in the field of spillways.