Aerodynamics of a bus with open windows

All authors:
Yelmule, M. M., Kale, S. R., Veeravalli, S. V.
Host organisation: CoE New Delhi, India
Country: India
Publication year: 2009
Published in:
Int.J.Heavy Vehicle Systems 16, 459‐488.
Research theme: Mobility and Access, Public Transport
bus, open windows, aerodynamics, air circulation, intervention, drag, comfort level
Research article
Most passenger trips worldwide are in open window buses where airflow due to motion provides comfort. The aerodynamics of such a bus was studied. Flow visualisations in a water channel using a 1:25 model showed highly turbulent inflow and outflow through rear and front windows, respectively. Large Eddy Simulation (LES) at the full-scale Reynolds number confirmed these features. Seven different interventions (in the form of slots on different surfaces) were considered. It was found that for the best configuration, the drag was reduced by 29% and the comfort zone increased from 11% to 52% of the passenger volume.
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