METHOD FOR SOURCE POWER IDENTIFICATION IN RICHARDS EQUATION
Abstract
In this paper a one-dimensional nonlinear Richards equation describing fluid flow in porous medium with inserted equalpowered sources is studied. An experimental iterational method is proposed to find source power to minimize the deviation of received humidity values from target values. Modeling was performed using numerical difference approximation of derivatives, resulting into a system of nonlinear equations with dependence from previous time step. The offered method allows to perform modeling for different source power values, and chooses the most suitable one.Iterations stop when they reach average modular difference value less than calculation error of numerical difference scheme. Here explicit scheme was used to save time, equations were tested for unsaturated medium only to avoid flooding the area, so source power is tested with given limitations. Results of simulations and choice for next source power approximations are described and compared until solution is found. This approach is considered as experimental so we plan to perform more analysis in the future.
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