Numerical Investigation of Active Flow Control Around a Generic Truck A-Pillar

Area of Science:

• Fluid Dynamics
• Aerodynamics
• Computational Fluid Dynamics

Background:

• Flow separation at bluff body A-pillars increases aerodynamic drag.
• Controlling flow separation is crucial for vehicle efficiency.

Purpose of the Study:

• To investigate the use of Zero Net Mass Flux synthetic jets for flow control.
• To minimize flow separation at the A-pillars of a simplified truck model.
• To analyze the effects of synthetic jet actuation on the flow field and drag.

Main Methods:

• Large Eddy Simulations (LES) were employed to model the actuated flow.
• The study focused on a simplified truck section with rounded A-pillars.
• Flow post-processing involved modal and frequency decompositions.

Main Results:

• Synthetic jet actuation effectively reduced flow separation.
• Significant drag reduction was observed in the actuated flow.
• The interaction between flow structures and actuation was analyzed.

Conclusions:

• Zero Net Mass Flux synthetic jets are a viable method for drag reduction.
• An optimal actuation frequency was identified for maximizing drag reduction and controlling flow fluctuations.
• Understanding flow mechanisms is key to effective aerodynamic control.