Numerical Simulation of Unsteady Flow around Ahmed Body with Active Flow Control

Abstract:

The numerical investigations presented in this paper deal with active flow control approach at the rear end of the Ahmed body model with the slant angle of 25°.Results of the velocity, pressure and vorticity field demonstrate the main reasons that cause the pressure drag. The influence of the spanwise and streamwise vortices rolling up from the slant and the edges on the recirculation zone behind the body is examined. A control slot is set on the separated line at the conjunction of the roof and the slant. Two different actuation concepts by blowing and suction steady jets through the slot lead to a drug increase of 5.61% and a drug reduction of 13.20% with the efficiency of 12.53% respectively.

• Periodical: Applied Mechanics and Materials (Volumes 275-277)
• Pages: 402-408
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.275-277.402
• Online since: January 2013
• Authors: Bing Xin Wang, Zhu Hui, Zhi Gang Yang
• Keywords: Active Control, Aerodynamic, Ahmed Body, Large Eddy Simulation (LES)

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