CUTTING TRANSPORT ANALYSIS IN HORIZONTAL WELLS: A COMPUTATIONAL APPROACH

Restricted (Penn State Only)
Author:
Alsuwaidi, Erhamah Salem
Graduate Program:
Petroleum and Mineral Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
January 30, 2018
Committee Members:
  • John Yilin Wang, Thesis Advisor
Keywords:
  • horizontal well
  • hole cleaning
  • cuttings
  • transport
Abstract:
Horizontal well is one of the most important methods that enhances the well production. On the other hand, drilling a successful horizontal well needs engineering attentions and optimizations. Clean wellbores is very an essential engineering parameter, where the key is to understand cuttings transport in different geological conditions and with different drilling parameters. During the past decades, substantial amount of lab work has been done to study the parameters that influences the cuttings transport performance. In this work, a numerical model was created to investigate the effect of parameters on the cuttings transport systematically. A parametric study was carried out to investigate the effects of cuttings size, cuttings density, mud weight, drill pipe rotation, drill pipe eccentricity, drilling rate, and circulation rate on the transportation of cuttings. The results of the numerical model showed a match with what other researchers have done in the lab. The results of the parametric study showed that the effect of altering the parameters was negligible when the well is in a vertical orientation. For high angles of inclination, simulating cuttings with low densities resulted with lower volume fractions of settled cuttings when compared with the result of simulating higher density cuttings. Also, the parametric study showed that smaller cuttings were easy to transport through the annulus. Therefore, the drilling engineer must try to break the lithology as small as possible to ensure better cuttings transport. Increasing the mud weight showed a significant improvement in the cuttings transport. But, on the other hand, the drilling engineering must be careful when using muds with high weights. Drill pipe rotation resulted with cleaner wellbore when it was implemented at high inclination angles. Negative drill pipe eccentricity results with significantly high cuttings’ volume fraction which can lead to catastrophic failures. Increasing the drilling rate iv helps with decreasing the drilling time, but it also results with high cuttings accumulation. The circulation rate showed an inverse relationship the cuttings volume fraction.