A transient flow model for multilateral horizontal wells in bottom water drive reservoirs

Abstract

The aim of this paper is to describe the pressure dynamic behaviour around a multilateral horizontal well in bottom water reservoir and get the productivity by establishing an analytical transient flow model. An exact solution of the model is derived by means of orthogonal transformation, method of mirror images and the theory of potential superimposition. For bottom water reservoirs, there is a supplementary boundary for the water aquifer. Given enough time, the transient flow will change to steady flow gradually. Correspondingly, the productivity index for wells in bottom water drive reservoirs can be calculated. We conclude that the analytical solution to the model can provide a valuable tool to compute the productivity and pressure dynamic behaviour of the multilateral horizontal wells in the bottom water reservoirs. Moreover, the case study shows that the calculated results agree with the practical situation. [Received: August 12, 2017; Accepted: March 16,2018]