DefinePK

Abstract

Before year 2000, elliptical flow regime was considered as a transition period found in a horizontal well transient test. It is recognized by a 0.36-slope (or 0.35-slope) tendency on the pressure derivative plot. Few researches have been conducted on the transient analysis for such flow regime. Since the first model does not provide a practical way of obtaining the reservoir horizontal permeability, a new model which is function of the reservoir length along the <i>x</i>-direction, reservoir thickness, horizontal wellbore length, well radius and horizontal reservoir permeability, was presented in 2004. Our experience, however, has indicated to us that this model sometimes fails to provide accurate values of horizontal permeability. Therefore, the first model presented in the literature, which depends upon the permeabilities in the horizontal direction, has been retaken in this study with a slight modification and successfully tested in many scenarios. The conventional straight-line and <i>TDS</i> methods are used as interpretation techniques for crude and gas flow. Both real time and pseudotime were implemented for gas flow.