(495b) Modeling and Simulation of Fluid Flow During Deep Drilling Process

Due to ever increasing demands of gas in the United States and worldwide, shallow gas reservoirs are disappearing. The giant gas reserves lurk several miles beneath the Earth's surface where high temperatures and high pressures conditions prevail and render the environment hostile to down-hole tools. It is estimated that 169-187 trillion cubic feet of technically recoverable natural gas are trapped in reservoirs below 15,000 feet. The United States Department of Energy-National Energy Technology Laboratory is attempting to understand the deep drilling process at extreme conditions of temperature and pressure. During drilling process, particulate multiphase drilling fluids are continuously cycled through the drill assembly. The drilling fluid performs many functions simultaneously. Some of the functions are transport of drilled solids from the wellbore and release them at the surface, lubricate the drilling assembly, and seal the well wall in permeable formation by forming a filter cake at the wall. The present research uses computational fluid dynamics technique to simulate the fluid flow during deep drilling process at high temperature (170oC) and high pressure (25,500 psi) as well as the filter cake formation at the well wall. The effects of drilled particles volume fractions (from 0.4 to 1.0) on the fluid flow pattern and filter cake formation have also been investigated.