AUTHORS: Masaru Sumida
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ABSTRACT: An advanced wind tunnel has been introduced as a facility for road vehicle development at the Kindai University (KURING). In this paper, the features of this wind tunnel, which can generate arbitrary patterns of time-varying wind velocities, are first described. There are four representative airflow patterns: steady wind with constant velocity, pulsating wind with oscillating velocity, gusts of wind, and stepwise-varying wind. The patterns are programmable and easy to operate. Using this wind tunnel, a basic test under unsteady wind conditions was conducted to obtain the characteristics of the fluid forces on the vehicle model subjected to the pulsating wind. Then, the different influences of the wind oscillation on the fluid forces acting on the model were discussed. It was concluded that wind oscillation produces striking effects on the vehicles. These results suggest that it is very important to test vehicles under unsteady wind conditions, and that this wind tunnel is very useful to investigate the unsteady aerodynamics of road vehicles.
KEYWORDS: Advanced Wind Tunnel, Road Vehicle, Time-Dependent Wind, Fluid Force, Ahmed Model, Pulsating Wind
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