Hydraulics of a finite-diameter horizontal well with wellbore storage and skin effect

We have obtained solutions of groundwater flow to a finite-diameter horizontal well including wellbore storage and skin effect in a three-dimensionally anisotropic leaky aquifer. These solutions improve previous line source solutions by considering realistic well geometry and offer better description of drawdown near the horizontal well. These solutions are derived on the basis of the separation of the source and the geometric functions. The source function is analyzed using Laplace transformation, and the geometric function is derived based on the method of superposition. The solution in a confined aquifer is derived as a special case of the solution in a leaky aquifer. The graphically integrated computer program FINHOW is written to generate type curves of groundwater flow to a finite-diameter horizontal well. The influence of the finite-diameter of the well, the wellbore storage, the skin effect, the leakage parameter, and the aquifer anisotropy is thoroughly analyzed. The well diameter, the wellbore storage, the skin effect, and the aquifer anisotropy substantially affect the near-well early time drawdown if compared to the line source solution, but they have negligible influence upon the far field or late time drawdown. This research provides a better tool for interpreting finite-diameter horizontal well pumping tests.