An Inflow Performance Relationship for Horizontal Gas Wells

Abstract

Abstract As an increasing number of horizontal gas wells are drilled, the need for a quick and reliable method to estimate the pressure-rate behavior of these wells is important to optimize well performance and make operational decisions. A reliable empirical relationship will provide engineers a technique to assess the performance of horizontal gas wells prior to undertaking extensive and often time-consuming simulation studies to model the well behavior. This work presents an analysis of the pressure-rate performance of horizontal gas wells using a three-dimensional finite difference reservoir simulator for different reservoir and wellbore conditions. The primary objective of this work is to study the pressure-rate behavior of horizontal gas wells and develop an empirical inflow performance relationship to predict their behavior. The study investigates a range of reservoir conditions to assess their effect on horizontal gas well behavior. Parameters studied include reservoir permeability, permeability anisotropy, gas gravity, drainage area, pay thickness and horizontal wellbore length. The obtained data is used to develop empirical inflow performance relationships (IPRs) to predict the pressure-rate behavior of gas wells. The IPRs are presented in terms of pressure, pressure-squared, and pseudopressure. The resulting IPRs provide a tool by which the petroleum engineer can quickly estimate the performance of a horizontal gas well without undertaking a time-consuming simulation study.