Chaotic Sequence Optimization Algorithm for Estimation of Aquifer Parameters from Data of Pumping Test

With chaotic sequence optimization algorithm,the function optimization problem for analyzing data pumping test conducted in aquifer to estimate such aquifer parameters as transmissivity and storage coefficient was to be solved. With such different key parameters of the algorithm as the number of coarse search loops, the length of chaotic sequence and the initial guess value ranges of transmissivity of aquifer, simulation experiment was conducted to explore the effect of these key parameters on the convergence of the algorithm. The results show: 1) that chaotic sequence optimization algorithm may be successfully applied to solve the function optimization problem to analyses pumping test data for determining aquifer parameters of aquifer, 2) that the longer sequence length of chaotic sequence and the larger number of coarse search loops may not effectively improve the convergence of algorithm, 3) and that the range of initial guess value of transmissivity of aquifer may brings some influence on the convergence of algorithm, but does not affect the final result of computation. Compared with current methods, the chaotic sequence optimization method is of such advantages as that the principle of algorithm is easy to understand, the procedure of the algorithm is easier to be programmed and conducted,and the precision of aquifer parameters calculated may not be affected by artificial subjective factors. Finally, it is necessary to point out that this method is of wider scope of application.