Rheological Modeling and Numerical Simulation of Annular Flow of a Drilling Mud Based on Local Materials: Theoretical Parametric Study

Abstract

Environmentally friendly drilling fluids based on locally available materials represent a promising alternative to conventional formulations. This study investigates the potential use of kaolinitic clay from Brazzaville (Republic of the Congo), okra (Abelmoschus esculentus L.) mucilage, and plant ashes as components of a bio‐based drilling mud. A theoretical and numerical framework was developed to simulate the annular flow of these non‐Newtonian fluids using the Bingham and power‐law rheological models. Analytical solutions were combined with finite‐volume simulations implemented in MATLAB to evaluate velocity profiles and pressure losses under representative drilling conditions. The results show that yield‐stress fluids develop a central plug region that can improve drill cuttings transport, whereas shear‐thinning behavior significantly reduces pressure losses compared with a Newtonian fluid while maintaining favorable flow characteristics. The numerical predictions are in excellent agreement with the analytical solutions, demonstrating the reliability of the proposed model. The main contribution of this work is the development of a modeling framework specifically adapted to drilling muds formulated from locally available Congolese materials, providing a basis for future rheological measurements and experimental validation. This study supports the development of sustainable and low‐cost drilling fluids for petroleum and geothermal applications.