Three-dimensional numerical study on aerodynamics of non-flapping bird flight

Numerical investigations have been carried out to study aerodynamics of non-flapping characteristics of bird flight. Commercial software ANSYS Fluent 16.1 has been used for three-dimensional computations by considering four types of wing models. At first, square prisms with built-in side flaps are considered and the effects of Reynolds number (Re), angle of attack and dihedral angle on flow characteristics have been investigated. Thereafter, flow past actual bird wing has been considered for wings of owl, seagull, teal and bat. Role of shear layer formation at mid-span of wings has been illustrated with the help of streamline plots for different values of Re. In addition, pulsating flow is imposed on inlet velocity and the responses are obtained in form of force coefficients, phase portraits, time-dependent signals and their spectra.