Analysis of the Aerodynamic Character of Bionic Wingspan on the Basis of Frigate Wing Structure

Abstract

This paper extracts the frigate bird’s leading edge contour by CATIA on the basis of the obverse and side pictures when frigate bird glides. Then three bionic wingspans of bending update, forward and integrating the two are built combining NACA 4412 airfoil. Compared with simple wingspan, the drag force of testing wingspan can be suppressed significantly, because the wingspan bending forward can form airflow of S style which declines the slope of the path-line of airflow and reduces the leading edge’s pressures. As a result the working condition is improved because the bending forward wingspan reduces air’s velocity. The lift efficiency of bending update wingspan may be improved because of increasing the leading edge’s pressure resulting in high speed airflow. Key words: leading edge contour; bionic wingspans; NACA 4412; aerodynamic performance