Evaluating Productivity Index in a Gas Well Using Regression Analysis

In this study, a new approach is introduced to augment existing correlations for the analysis of Productivity Index of a gas well. The Modified Isochronal test method is used in this analysis. The Productivity Index trend of the gas well is evaluated from the test data. Regression Analysis is used to develop a correlation, which is then used to evaluate andforecast future Productivity Index trend. The back pressure equation of the Simplified Analysis method is also used to examine the test data. The Inflow Performance Relationship data generated is compared with that generated from Regression Analysis. In the Regression Analysis, using pseudo-pressure approach evaluates productivity index of the gas well more accurately than the pressure-squared approach. The bottom-hole pressure method using the pressure-squared approach under Regression Analysis generated a better estimate of IPR data, than any other method.The Productivity Index values evaluated from the Regression Analysis are quite approximate and can be used to establish a deliverability equation for the gas well.