Modelling of steady gas-liquid-solid three-phase flow with application to oil well drilling

摘要

Aerated oil well drilling is a technique in which gas and mud are simultaneously injected into the well. Together with the rock fragments cut off by the drill bit this leads to a three-phase flow. For planning purposes it is necessary to predict the gas and mud flow rates that lead to a given bottom hole pressure. In this paper a model is presented that simulates aerated mud drilling. It consists of conservation equations of mass and mixture momentum, complemented by drift-flux equations. Closure modelling is provided. Some preliminary calculations shed light on the physics of the drilling operation.