Solution of Critical Water Depth Trapezoid Open Channel by SARAGA

The critical depth of water is an important hydraulic parameter in open channel hydraulics, which is a key sign of the state of water flow in open channel. Some usual method for calculating critical water depth of trapezoid open channel are trial method, approximate solution and iteration method, whose shortcomings are needing great quantity of calculation and rough accuracy of solution. A method of Accelerating Genetic Algorithm based on real coding (RAGA) was adopted to overcome the shortcomings in this paper. The Simulated Annealing algorithm (SA) was used to improve the convergence rate during the late of evolution of RAGA. The result of case study shows that SA can prevent from a local optimal value during the course of late period of optimization of RAGA and it is showed that convergence rate of SARAGA was faster 20% than that of RAGA. The accuracy of calculated results of SARAGA is higher than that of usual optimal methods for solve a critical depth of trapezoid open channel. Furthermore, SARAGA can be used to deal with some optimization problems in other fields.