The Experimentally and Numerically Determination Of The Drag Coefficient Of A Bus Model

Abstract

In this study, the drag coefficient of a 1/33 scaled bus model were determined by experimentally in wind tunnel and numerically in Fluent®. The tests were performed at 6 different free flow rates and between the range of 382 866- 792 900 Reynolds numbers and 13.54m/s - 28.05m/s free flow velocity. The three similarity conditions were provided in tests. The flow analyses were conducted in 1/40 scaled wind tunel as experimentally using Reynolds independent. The aerodynamic drag coefficient (CD) of the bus model was calculated as 0.633 in wind tunnel. The experimental results of bus model are verificated by numerical flow analysis in Fluent® program. According to numerical results, the drag coefficient of bus model is calculated as 0.645 with 1.81% error margin.

Keywords

• Vehicle aerodynamic,drag coefficient,wind tunnel,bus model,CFD,Fluent

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