An Analysis of Pressure Drops in Wellbore, Under Low Flow Rate Conditions, Shown on a Deliverability Curve

Abstract

This study investigated pressure drops in wellbore under low flow rate conditions and shows them on a deliverability curve. A simple model of a vertical wellbore of uniform diameter, coupled with a reservoir of uniform, radial, horizontal thickness was employed. The momentum equation for two-phase flow in a wellbore was numerically evaluated using a method introduced by Orkiszewski (1 967). Isenthalpic conditions were assumed for the energy equation. The numerical calculation showed that at low flow rates, the pressure drops in the wellbore were dominated by a potential pressure drop component then followed by a fkiction component and finally an acceleration component. As the flow rate increased the potential pressure drop decreased while the two other components tended to increase. The decrease in the total flow rate results in a decrease in the slug regime length in the wellbore.