Choked Gas Flow at Pore Scale and Its Implications to Production From High Pressure Gas Wells

Abstract

Production from a highpressure gas well at a high production rate encounters the risk of wellbore tensile failure when the pressure gradient of the averaged gas flow becomes large. At the porescale, however, when flow in just one pore is choked, gas pressure gradient at the point of choking becomes singular, leading to an unbounded average of the pressure gradient. This study investigates the choking condition for compressible gas flow in a single pore. It is found that wellbore tensile failure can occur at a much lower inlettooutlet pressure ratio than predicted from the macroscopic theory of porous medium flow.