Novel Viscometer Design for Investigation of the Rheological Properties of Drilling Fluid at Low and High Shear Rate Conditions

Abstract Understanding the behavior of non-Newtonian drilling fluids under varying flow conditions is crucial for optimizing cuttings transport and improving drilling performance. This study presents an advanced high-speed viscometer based on the Taylor-Couette system (TCV) to evaluate the rheological properties of drilling fluids under both laminar and turbulent flow conditions. The newly developed viscometer features a low volume capacity of 100 ml and operates at speeds ranging from 0 to 3000 RPM, adjustable in 10 or 100 RPM increments, enabling precise measurements at different shear rates. Experimental investigations compared the results obtained from this novel viscometer with those from the conventional 8-speed Fann viscometer. Following recalibration, the enhanced AU Taylor-Couette Viscometer (AUTCSV) demonstrated consistency with established industry standards, confirming its reliability in assessing fluid behavior at high shear rates. The insights gained from this study contribute to a more accurate understanding of fluid flow dynamics, ultimately improving modeling efforts for cuttings transport and optimizing drilling operations under both laminar and turbulent flow regimes. These findings have significant implications for enhancing drilling efficiency and operational success in complex wellbore environments. Keywords: high-speed viscometer, turbulent flow, laminar flow, drilling performance.