A new algorithm for computation of horizontal-well pressure in laplace domain

Abstract

The effect of wellbore pressure drop on horizontal well pressure response is relatively important when flow velocity is high or the surface of horizontal wellbore is rough. The objective of this study is to develop a stable and robust algorithm in Laplace domain to analyze horizontal-well pressure with pressure drop along the wellbore. Based on the novel definitions of horizontal well permeability and conductivity, the equation of fluid flow along a horizontal wellbore with pressure drop has the same form as that of fluid flow in a varying-conductivity fracture. A new dimension transformation has been used to change the varying-conductivity model into a constant-conductivity model, and then an iterative procedure has been introduced to obtain the pressure. This algorithm is developed in Laplace domain and eliminates the need for computations in the time domain. Besides, the skin effect and wellbore storage is easily to be taken into consideration.