Abstract
A new numerical scheme for solving transient pressure in a confined aquifer is presented. It is based on the fundamental solution method (FSM) and it combines free Green functions, superposition principle, and singular value decomposition (SVD) method to obtain an efficient computational algorithm to approximate unsteady pressure in general two dimensional groundwater problems. Its mathematical formulation avoids integral equations, is meshfree, and its new multistep approach provides very accurate approximation of full transient aquifer pressure along any period of time. The new scheme was validated with synthetic aquifers problems with constant and variable well rates. Its applications to arbitrary shaped aquifer with multiple wells is developed and analyzed. Numerical results gave evidence that the new scheme is a versatile tool and an alternative choice to boundary element methods to solve groundwater problems.
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