Influence of Thickness Ratio on the Aerodynamic Characteristics of a Family of Hybrid Semielliptical Dolphin Airfoils

The authors of this paper have recently been involved in the development of a novel family of semielliptical hybrid Dolphin airfoils for general aviation applications. The previous work has shown noticeable improvements in aerodynamic characteristics of the modified hybrid Dolphin 2415 airfoil. In this paper, the same method has been applied to the airfoils of different thickness ratios. All numerical calculations were performed using RANS equations with the k−ω SST turbulence model. A comparison between a series of four-digit NACA 24xx, the original Dolphin, and the novel hybrid semielliptical Dolphin airfoils was made. Results have shown that in the range of thickness ratios above 15% and under 12%, the semielliptical hybrid Dolphin airfoils have shown a slight decrease in some aerodynamic characteristics compared to their NACA counterparts. This led to the conclusion that the semielliptical modification approach of the airfoil in its nose domain shows the best results within the 12–15% range of thicknesses, which is an important clue for further research of the hybrid Dolphin airfoils.