Friction reduction of Al₂O₃, SiO₂, and TiO₂ nanoparticles added to non-Newtonian water based mud in a rotating medium

In drilling industry, energy consumption counts from 20 to 40 percent of total costs. Enhanced water-based mud (WBM) drilling fluids with nanoparticles can save energy in drilling processes. An in-house Taylor-Couette flow system (TCS) was developed at Australian University (AU) to study WBM enhanced by Al₂O₃, SiO₂, and TiO₂ nanoparticles. The TCS is really a practical tool to help well drillers with a rough idea of viscosity when nanoparticles are added. The TCS for sure cannot substitute advanced rheometry. The goal of the present experiment is to produce a rough estimate in field operation. Experimental results were examined with several rheology models in our previous publications. In the present work, the enhanced WBM of Al₂O₃, SiO₂, and TiO₂ nanofluids are compared with each other at very low volume fractions of 0.05%, 0.1%, 0.5% and 1% and at TCS rotational speeds of 200–1600 RPM. Results in form of consistency charts for shear stress and apparent viscosity are presented here. It is observed that both shear stress and apparent viscosity were reduced for all the nanofluids. Also results for Darcy friction factor were evaluated. It is observed that TiO₂ nanofluid friction factor was significantly reduced by 42–76% at the volume fraction of 0.05%; Al₂O₃ by 36–50% at 0.1%; TiO₂ by 40–53% at 0.5%; and Al₂O₃ by 23–50% at 1.0%; respectively. SiO₂ nanofluid friction factor was lightly reduced by 30–45%. Enhancement of WBM with nanoparticles were significant at lower volume fractions and at lower TCS speeds.