COMPUTING WELL HYDRAULICS SOLUTIONS

Abstract. Type curves, and drawdown analysis curves of other sorts, have a well-established position in the ground-water profession. Although a plethora of solutions to well hydraulics problems exists, many of these arc not available in useful type curve formats. lpurthcr, if one wants to perform parameter estimation using many of these solutions, a computer-based form of the solution is needed. Those who have programmed analytical solutions know the difficulties that will be encountered in coding even the most innocuous-looking result. In this paper, a computer-based method of type curve generation is prcscnted based on Stehfest's method of inverting the Laplace transform solution of ground-water flow problems. The latter are usually easier to obtain than a complete closed-form solution. The method is very robust for a large class of well hydraulics problems. A companion diskette with FORTRAN source and executable example program is available from the author.