Experimental study on calculation of hydro-geological parameters for unsteady flow

Abstract

After the linear analytical method of unsteady flow theory is further improved, an innovative and faster algorithm is introduced. The water storage in a confined aquifer is derived from the water transmissivity coefficient and the water-pressure conductivity coefficient. The water transmissivity coefficient is approximated by a Taylorseries expansion of drawdown, and the water-pressure conductivity coefficient is obtained by the average drawdown. In this algorithm, the distance of the observation points from the pumping well must be short. When the distance is as short as the radius of the main pumping well, the data of the drawdown difference between the sidewall and the center of pumping well are difficult to measure, but the same results can be achieved based on the assumption that the drawdown difference approximates to the drawdown of the observation wells at a radial distance from the pumping well according to the algorithm. Without the help of charts, this algorithm is more concise and efficient, which has been verified by the test of water pumping project in Tianjin Binhai International Airport.

Keywords

pumping test / unsteady flow theory / improved linear analytical method / hydro-geological parameter

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