Research on aerodynamic performance of a new dolphin head-based bionic airfoil

Abstract Based on the special streamline profile of the Phocoenoides dalli head, this paper innovatively proposes to transform the NACA0018 airfoil into a new airfoil whose leading edge is similar to the streamline profile of the Phocoenoides dalli head, and makes corresponding minor adjustments to this new airfoil according to the dolphin's motion behavior, and eventually obtains three kinds of dolphin-like new airfoils including Original Dolphin Airfoil, Smooth Transition Dolphin Airfoil and Deflected Dolphin Airfoil. Due to the different deflection angles, the Deflected Dolphin Airfoil is subdivided into five different types. The aerodynamic performance of these three dolphin-like new airfoils as well as the NACA0018 airfoil is simulated by using SST k-ω model at Re = 1.6 × 105. The results show that: Compared with NACA0018 airfoil, firstly, the aerodynamic performance of three kinds of dolphin-like airfoils are quite different from each other because of the change of the curvature and the radius of the leading edge. Secondly, by comparing the lift and drag coefficients of Deflected Dolphin Airfoil with the five deflection angles, it is speculated that there is an optimal deflection angle for the Deflected Dolphin Airfoil under the conditions of this paper, and the 24° deflection angle is closest to the optimal deflection angle among the five different deflection angles. The results of this study can provide reference for improving the performance of blade design,such as rotating mechanical blades, the aeronautical blades, etc.