However, they showed that at low angles of attack, the heat transfer enhances lift to drag coefficient ratio. doi: 10.2514/6.1995-2298įound that the maximum lift, the maximum lift to drag coefficient ratio and the lift curve slope of a NACA0012-64 airfoil are reduced by heating the surfaces. Presented at: 26th Fluid Dynamics Conference San Diego, USA. By solving the N-S equations at the Re of 10 6, Longo and Radespiel (1995) Longo J, Radespiel R (1995) Numerical simulation of heat transfer effects on 2-D steady subsonic flows. He revealed that cooling the surfaces decreases Re and delays the flow separation. Studied the effects of the heat transfer on aerodynamic of different bodies at the Re of 10 6. Mabey (1990) Mabey DG (1990) Effects of heat transfer on aerodynamics and possible implications for wind tunnel tests. doi: 10.2514/6.1987-1259Įxperimentally studied the effects of leading edge heating on two dimensions boundary layer characteristics. Presented at: 19th AIAA, Fluid Dynamics, Plasma Dynamics, and Lasers Conference Honolulu, USA. Landrum and Macha (1987) Landrum D, Macha J (1987) Influence of a heated leading edge on boundary layer growth, stability, and transition. Results of wind tunnel tests showed that the drag increases by heating the surfaces. Performed analytical and experimental studies to investigate the boundary layer of a NACA0012 airfoil at the Re of 10 5. (1973) Norton DJ, Macha JM, Young JC (1973) Surface temperature effect on subsonic stall. Thermal effects on the flow can be clarified by investigation of the airfoils in steady conditions. On the other hand, the theory of using heat transfer based on the viscous boundary layer characteristics can also be utilized to improve the aerodynamic efficiency. Therefore, many methods, including optimization of airfoil shape, blowing and suction, have been used in those studies to overcome mentioned problems. Finally, this separation increases the drag and reduces the lift ( Febi Ponwin and Rajkumar 2015 Febi Ponwin S, Rajkumar S (2015) Methods for improving lift force of wind turbine aerofoil blades during low wind speed conditions - a review. The separation happens either at leading edge or trailing edge. In this range of Re, the adverse pressure gradient plays a destructive role in aerodynamic performance and consequently causes flow separation over the airfoil. The motivation of recent attempts is to improve the aerodynamic performance in Low Reynolds Number (LRN) flows. Thermal camber Aerodynamic CFD Low Reynolds numberĭue to the importance of Micro Aerial Vehicles (MAV), many studies have been done to develop this field of research. Also, when this method is applied to the NACA2412 and NACA4412 airfoils, lift to drag coefficient ratio will increase more than the condition with only cooling or heating the surfaces. These improvements are more than the airfoils with physical camber. After validation, results indicated that cooling upper surface and heating lower surface, namely thermal camber, generate lift force and improve aerodynamic performance for symmetric airfoils at a 0° Angle of Attack ( AOA). Furthermore, various temperatures are tested in order to find the optimum condition. Hence, a symmetric airfoil, like NACA0012, with thermal camber is compared with the airfoils with the physical camber, including NACA2412 and NACA4412, to specify which camber type has more effects on the aerodynamic efficiency. This phenomenon is used to improve the aerodynamic performance. The main objective of this paper is the introduction of the thermal camber phenomenon. Navier-Stokes (N-S) equations are discretized by Finite Volume Method (FVM) and are solved by the SIMPLE algorithm in an open source software, namely OpenFOAM. In this research, viscous, laminar and steady flow around symmetric and non-symmetric airfoils is simulated at Low Reynolds Number (LRN).
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