CFD analysis of lift, drag, and moment coefficients of a tandem airfoil under ground effect

Abstract

In the present study, an examination of the aerodynamic characteristics in tandem airfoil systems experiencing ground effect was performed. The research was carried out using Computational Fluid Dynamics (CFD) analyses. The effects of multiple parameters, such as angle of attack (AOA) at 0°, 4°, and 8°, horizontal distance between the front and rear airfoils (d/c), proximity to the ground (h/c) and Reynolds number on lift (CL), drag (CD), and moment (Cm) coefficients were investigated. The best aerodynamic performance (maximum CL/CD) was achieved at a 4° AOA, very close to the ground (h/c=0.1), in the range of 1≤d/c≤2 and higher Reynolds number. It was also determined that the 0° AOA exhibited a distinctly different behavior from the other angles (4° and 8°), as decreasing ground clearance led to a reduction in CL at 0°, whereas it caused an increase at 4° and 8°.

Keywords

• Tandem airfoils
• Ground effect
• Lift
• Drag
• Moment
• CFD

Kaynakça

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