Development and Performance Assessment of Nanoparticle-Based Smart Drilling Fluids for Enhanced Wellbore Stability

The well construction process is inherently linked to the destruction of rock formations within the wellbore and the transportation of drilled cuttings to the surface. Therefore, one of the most critical technological aspects of well construction is the effective cleaning of the wellbore by drilling fluids. A rise in temperature can lead to significant changes in the properties of drilling fluids, such as a reduction in viscosity, increased fluid loss, and a decrease in rheological parameters. These changes negatively impact the wellbore cleaning efficiency, which may result in severe operational challenges, including wellbore collapse and drill string sticking. This research explores the effects of incorporating nanoparticles into water-based drilling fluids on their rheological behaviour, fluid loss control, thermal stability, and electrical resistivity within a temperature range of 25°C to 90°C. The nanoparticles used in this study include Silica (SiO₂), Iron Oxide (Fe₂O₃), Zinc Oxide (ZnO), Magnetic Iron Oxide (Fe₃O₄), and Nanoclay. To evaluate the relationship between shear stress and shear rate, two rheological models were applied: the Herschel-Bulkley model and the Vipulanandan model. Moreover, the Static (API) fluid loss model and the Vipulanandan fluid loss model were used to monitor changes in fluid loss over time. This research highlights the potential of nanoparticle-enhanced drilling fluids to improve efficiency and stability under high-pressure, high-temperature (HP/HT) conditions. Among the tested nanoparticles, Magnetic (Fe₃O₄) demonstrated the most significant enhancements in rheological properties and fluid loss control compared to the base mud. Furthermore, electrical resistivity measurements indicated that nanoparticles influenced the fluid’s electrical properties, potentially affecting the accuracy of well-logging operations.