Optimizing Fuel Efficiency in Intercity Buses: Aerodynamic Design Enhancements and Implications for Sustainable Transportation in Bangladesh

This study explored the aerodynamic aspects of the Hyundai Universe Express Noble bus, a common passenger bus model in Bangladesh, and proposed modifications to improve its performance. The airflow around the bus was analyzed using Computational Fluid Dynamics (CFD) simulations. Consequently, areas of high drag and turbulence were identified. These results led to the redesign and testing of several shape modifications for the bus, including adjustments to the roof spoiler, side mirrors, and front grille. After finding the bus model with the lowest drag coefficient, that model is further analyzed to find the aerodynamic effects of side windows on a bus and their impact on fuel efficiency. The aim is to determine how much side windows significantly affect fuel efficiency. The aerodynamic effect with windows open and closed is also evaluated after identifying an appropriate model. Model 1.2 uses 7.72% less fuel than base Model 1.0. Model 1.2 with windows uses 2.5% more fuel than Model 1.2. The study also evaluates the fuel cost per 500 km for all models suggesting that non-ac buses with side windows consume slightly more fuel than AC buses. Changing the bus shape to Model 1.2 will reduce the drag coefficient by 8.67% and fuel consumption by 7.72%. The study offers insights into reducing drag force, minimizing air resistance, enhancing exterior styling, and improving vehicle stability. Furthermore, these findings have practical implications for the transportation industry as they demonstrate the potential for improving the efficiency and sustainability of large vehicles through aerodynamic design.