Prediction of Critical Foam Velocity for Effective Cuttings Transport with Foam in Horizontal Wells

Abstract

A mathematical model and a numerical analysis of the cuttings transport with foam in horizontal wells have been presented earlier. The model has been incorporated into a computer program and used for finding a closed form critical foam velocity (CFV) correlation. The new CFV correlation can be used to predict minimum foam flow rate required to remove or prevent the formation of stationary cuttings beds in highly deviated and horizontal wells. Effects of key drilling parameters (i.e., drilling rate, annular geometry, foam quality, bottomhole pressure, and temperature) on the critical foam velocity have also been investigated. Numerical examples are presented to illustrate how the CFV correlation can be used to determine required gas and liquid flow rates at the downhole conditions.

Keywords:

• cuttings transport
• foam drilling
• horizontal wells

Acknowledgment

This work is supported through the research grant provided by the Natural Sciences and Engineering Research Council (NSERC) of Canada.