Pressure-Transient Analysis of Oil Wells after a Short-Term Disturbance of the Formation

The study addresses the problem of unsteady fluid filtration in the vicinity of a vertical well after a short-term disturbance of the formation taking into account the skin effect and wellbore storage effect. The numerical solution of the problem is compared with the approximate Muskat solution. A method for interpretation of the pressure-transient data for vertical wells penetrating low-permeability formations based on the theory of ill-posed problems is proposed. The estimates of the well productivity index and formation pressure obtained by the proposed method are compared with those determined by the integral method and the Muskat method using real data on the bottomhole pressure build-up.