COMPUTATIONAL FLUID DYNAMICS (CFD) ANALYSIS OF EXTERNAL CORROSION IN NIGERIAN OIL AND GAS PIPELINES
External corrosion remains a major threat to the integrity, safety, and reliability of buried oil and gas pipelines in Nigeria, largely due to complex interactions between soil chemistry, moisture, and climatic conditions. The aim of this study is to investigate the external corrosion behavior of the Ajaokuta�Kaduna�Kano (AKK) gas pipeline and quantify the influence of key environmental parameters on corrosion rate distribution along the pipeline corridor. A Computational Fluid Dynamics (CFD)�based electrochemical modeling approach was adopted, incorporating soil pH, moisture content, temperature, and humidity data obtained from five representative locations: Ajaokuta, Lokoja, Abaji, Kaduna, and Kano. Transient CFD simulations were performed using ANSYS Fluent, with corrosion kinetics implemented through the Butler�Volmer equation and corrosion rates computed via Faraday�s law. The results revealed that corrosion rates varied significantly with location, ranging from a minimum of 0.0114 mm/year in Kano, characterized by arid conditions and near-neutral soil pH, to a maximum of 0.1143 mm/year in Abaji, associated with higher humidity and more aggressive soil conditions. Soil pH values ranged between 5.0 and 8.5, while operating temperatures were within 305�310 K. Higher moisture content, elevated humidity, and lower soil pH were identified as the dominant factors accelerating external corrosion. It is recommended that location-specific corrosion mitigation strategies, including optimized cathodic protection, improved coating management, and continuous environmental monitoring, be implemented along the AKK pipeline to enhance long-term pipeline integrity and operational safety.
Authors : Waziri, A.M., Guma, T.N., Akindapo, J.O., Orueri, D.U. and Ajayi, F.I.
Category : Open Access Volume (Issue) : 11(2) Date Uploaded : 9th January 2026