Citation:

Olusola Oloruntoba, Oluwasanmi Alonge, Ojotu Joseph, Oluranti Abiola, 2023. Aerodynamic Study of Minibus in Open and Closed Window Scenarios, ESP Journal of Engineering & Technology Advancements  3(3): 15-22.

Abstract:

Several vehicles in tropical Africa, such as Nigeria, operate with open window, and this is expected to affect aerodynamics of the vehicles. Based on established theory, Aerodynamic drag is a major component of energy losses which limit the energy available to propel a vehicle. The goal of this study is to determine the effect of open window on the aerodynamics of a typical minibus. ANSYS™ FLUENT™, a Computational Fluid Dynamics program, is applied to conduct numerical study in this work; vehicle speed is taken as 100km/h. Results from this study show that a characteristic chaotic flow in experienced in and around the vehicle with open window, leading to corresponding development of a chaotic turbulent flow on the frontal exterior region adjacent to frontal window, as well as the occurrence of a characteristic horse-shoe shaped flow which is formed on the outside of the wheels. These phenomena die out towards the rear of the vehicle trail. The corresponding characteristic turbulent flow is limited for closed window vehicle. Furthermore, aerodynamic drag and lift coefficients for closed window scenario are determined as 0.5773 and -0.1161 respectively; these values are 10.29% and 56.43% lower than the corresponding values for open window vehicle. The implications of the findings are: (a) higher aerodynamic drag leads to increase energy loss, fuel consumption and CO2 emission, and (b) higher aerodynamic lift leads to reduced tire grip and increased instability, especially at corners.

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Keywords:

Aerodynamics, Open Window, Closed Window, CFD, Drag, Lift.