Experimental Study of Drag Reduction on a Model Car Using an Active Flow Control

Document Type : Research Article

Authors

Mechanical Engineering Department, Hakim Sabzevari University, Sabzevar, Iran

Abstract

Aerodynamic drag is one of the most important determinants of vehicle’s fuel consumption. Pressure drag which is the main component of total drag is a result of boundary layer separation from vehicle surface. In this paper, we investigate experimentally, the possibility of separation from the upper surface of model and the effect of base bleeding as an active flow control method on aerodynamic drag reduction of Ahmed body with 35 degree rear slant angle. Then optimum position of blowing on the slope and vertical surfaces at the end of model was found. Blowing increased static pressure in the wake and reduces the drag. In addition, pressure profile across the surface model, velocity and turbulence intensity in this paper is studied. The results showed that the jet flow in the best position
causes 21 % reduction in the drag coefficient. If the jet flow is applied on the upper position of inclined surface, it increases the drag coefficient. All tests are done in an open circuit blowing wind tunnel with maximum turbulent intensity of 1 % and maximum speed of 30 m/s. Velocity measuring components are carried out by hot-wire flow meters.

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References

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Amirkabir Journal of Mechanical Engineering
Volume 49, Issue 3
November 2017
Pages 435-444

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