1M. Sc. [Engg.] Student, Centre for Automotive Product Design
2Senior Lecturer, Centre for Automotive Product Design
3Professor and Head, Department of Mechanical and Manufacturing Engineering, M.S. Ramaiah School of Advanced Studies, Bangalore, 560054
Online published on 18 February, 2020.
Intercity buses travel about 250 to 350 km in a stretch and usually are of sleeper coach mode. The exterior styling, sleeper comfort and aerodynamically efficient design for reduced fuel consumption are the three essential factors for a successful operation in the competitive world. The bus body building companies prioritizes the exterior looks of the bus and ignore the aerodynamic aspect. Scientific design of sleepers for increased comfort of the passengers is seldom seen. The overall aim of this project was to redesign an intercity bus with enhanced exterior styling, reduced aerodynamic drag and increased comfort for the passengers.
Extensive product study and market study were carried out and aspirations and frustrations of commuters were recorded. An operating intercity bus was benchmarked and analyzed for styling, aerodynamic performance and comfort. Fluent, a commercial CFD code was used to evaluate the aerodynamic performance. Principles of product design were used to analyse the styling and comfort. The benchmarked high floor bus was redesigned with low-floor for reduced aerodynamic drag. The exterior was redesigned with emphasis on improvised aerodynamic performance and appealing looks. The interior was modified to meet aspirations of the commuters.
The results of the redesigned exterior body showed a reduction of Cd from 0.53 to 0.29 and overall aerodynamic drag reduction by 60% due to combined effect of reduced Cd and frontal area. The redesigned interior was found to be at the satisfaction of commuters.
Bus Aerodynamics, Drag Reduction, Low Floor Bus Design, Sleeper Coach
