Computational Fluid Dynamics

Open drain channels play a vital role in stormwater management and flood prevention in urban and agricultural environments. However, factors such as complex channel geometry, surface roughness, sediment accumulation, and turbulence often reduce their efficiency, leading to flooding and waterlogging. This study aimed to analyze fluid flow in an open drainage channel using Computational Fluid Dynamics (CFD) to understand flow behavior, identify hydraulic inefficiencies, and recommend design improvements for enhanced drainage performance. The study focused on an open drainage channel within the University of Benin, Ugbowo Campus, Benin City, Nigeria. Data on channel dimensions, flow conditions, and physical characteristics were obtained through site investigations and measurements. A three-dimensional model of the channel was developed and simulated using CFD techniques in SolidWorks Flow Simulation. The governing equations of fluid flow, including the continuity and Navier-Stokes equations, were solved under appropriate boundary conditions to evaluate velocity distribution and free- surface flow characteristics. The simulation results showed that flow velocity increased gradually along the channel length, with the highest velocities occurring near the outlet region. The free surface remained stable throughout the simulation, indicating efficient water conveyance under the specified flow conditions. The study concluded that CFD is an effective tool for predicting flow behavior and evaluating the hydraulic performance of open drainage systems. The findings provide valuable insights for improving drainage design, reducing flood risks, and promoting sustainable stormwater management.

The oil and gas industry depends extensively on centrifugal pumps for the transportation of crude oil; however, Cavitation remains a major operational challenge that reduces pump efficiency and lifespan. While cavitation in water and other fluids has been widely studied, limited research has focused on cavitation behavior in crude oil systems. This study addressed this gap by developing a numerical approach for investigating cavitation in crude oil centrifugal pumps using Computational Fluid Dynamics.

The research employed simulations using ANSYS to analyze complex flow patterns and cavitation behavior within a centrifugal pump. A multi-model approach was adopted, incorporating a bubble dynamics model to track the nucleation, growth, and collapse of vapor bubbles, a turbulence model to simulate chaotic fluid flow, and a multiphase model to represent interactions between the liquid and vapor phases of crude oil. The developed numerical model was validated by comparing simulation results with operational performance data from a centrifugal pump used in an oil rig, achieving a margin of error of approximately 0.5%.

The results highlighted the importance of considering crude oil properties and pump design parameters when addressing cavitation issues. In particular, casing surface roughness was identified as a critical factor influencing cavitation intensity, as even minor variations significantly increased cavitation activity. Additionally, crude oil backflow was found to play a major role in initiating discharge cavitation within the pump system.

The study concludes that accurate modeling of crude oil properties and pump design characteristics is essential for mitigating cavitation in centrifugal pumps. The findings provide valuable insights for improving pump design, operation, and maintenance strategies within the oil and gas industry