Application of the electric resistance tomographic technique to investigate its efficacy in cuttings transport in horizontal drilling scenarios

The present study is focused on the experimental evaluation of the non-intrusive electric resistance tomographic (ERT) technique in the presence of different types of water-based drilling fluids, i.e., Newtonian (water) and non-Newtonian (0.05 wt% and 0.1 wt% polymers). The experiments were conducted in a 6.16-m long horizontal flow loop with an inner and outer diameter of 2.5 and 4.5 inches. The tests covered a variety of hydrodynamic and operational parameters, such as the density (997–1001 kg/m3) and apparent viscosity (0.889–2.54 cP) of the fluids as well as different eccentric conditions (0–0.6), mass flow rates (170–365 kg/min), and drill pipe rotations (0–120 RPM) with horizontal drilling conditions. In this investigation, we analyzed the ERT-obtained average volume fraction (AVF), maximum volume fraction (MVF), and cuttings residence time. The results highlighted that the ERT technique is useful in situ tool for detecting solid particles in various cuttings transport scenarios (different drilling fluids, mass flow rates, and eccentricities). The findings also revealed that an increase in the liquid flow rate influenced cuttings transport. Non-Newtonian fluids performed relatively better than Newtonian (water) fluid at higher flow rates (for equivalent pump output and equivalent Reynold number conditions) as it provides higher AVF and MVF quantities due to their rheological properties hold cuttings in a suspended form. Inner pipe rotations also significantly enhanced the cuttings transport by adding induced helical motion and vorticities in the annulus. On the other hand, eccentricity in the annulus caused hindrance in the cuttings transport movement due to reduced active solid transportation or effective area, resulting in a more extended horizontal bed formation.