Effects of Surface Heating on the Aerodynamics of NACA 4412 Airfoil in Low Reynolds Number Flows

Ahmad Hussein Abdul Hamid ； Nur Izyan Azlaili Khairill Anwar ； Firdaus Mohamad ； Mohd Hafiz Mohd Noh ； Mohd Azan Mohammed Sapardi

《Journal of Aeronautics, Astronautics and Aviation》 54卷3期 Vol.54 No.3 AEROS 2021 Special Issue (2022/09) Pp. 357-363

https://doi.org/10.6125/JoAAA.202209_54(3).12

摘要

When the laminar boundary layer separates, the separated layer rapidly undergoes a transition into a turbulent flow, and this consequently reduces lift and increases drag forces of the airfoil. Many methods have been proposed to solve this problem, and one of them is the procedure of heat transfer based on viscous boundary layer characteristics. The main objective of this research is to study the effects of surface heating on global performance characteristics of the airfoil, such as lift and drag coefficients and point of flow separation at various angles of attack. In this study, the NACA 4412 airfoil is simulated in low Reynolds number flow with its surface heated to a constant temperature. The steady and transient solvers (buoyantSimpleFoam and buoyantPimpleFoam, respectively) are applied to solve the governing equations, and the Spalart-Allmaras turbulence model is adopted to close the RANS equations. Based on the results, it can be observed that the stall angle of attack and maximum lift coefficient are increased by respectively 1° and 0.4% when the surface of the airfoil is heated, with a post-stalling regime existing beyond the angle of attack of 20°. Moreover, a significant performance gain in the post-stall regime is also observed with the heated airfoil.

關鍵字

Lift ； Drag ； Stall ； Laminar separation bubble ； Heated airfoil

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