Calibração da condutividade hidráulica horizontal utilizando o método iterativo do gradiente hidráulico

Abstract

The process of calibration of hydrodynamic parameters represents an important part IN computer modeling; its general approach consists of minimizing an objective function expressed by the difference between observed and simulated hydraulics heads. Guo and Zhang (2000) and Schuster and Araújo (2004) proposed an alternative process for estimating the parameters, through the minimization of the difference between observed and simulated hydraulic gradients and denominated it Iterative Method of the Hydraulic Gradient (IMHG). The generation of the matrix of the observed heads has decisive function in the success of the calibration process. In the traditional approach, the observed matrix is obtained using a mathematical interpolation. This work intends to investigate the generation of the observed head matrix, using the simulation process itself, fixing, in the model, the points where the heads are known. Normally, great manual efforts were noticed in the attempt of integrating the simulating software (PMWIN) and the (IMHG); therefore, all calibration methodology was automatically implemented and a computer code was developed, denominated UFC-MIGH. For the application of the proposed methodology, the horizontal hydraulic conductivities of a hypothetical case were used and demonstrated smaller errors than the traditional methodology, implemented in the software PEST.