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Numerical investigation of vortex dynamics innear wake of a hovering hawkmoth and hovering aerody-namics is conducted to support the development of abiology-inspired dynamic flight simulator for flapping wing-based micro air vehicles.Realistic wing-body morphologiesand kinematics are adopted in the numerical simulations.The computed results show 3D mechanisms of vortical flowstructures in hawkrnoth-like hovering.A horseshoe-shapedprimary vortex is observed to wrap around each wing duringthe early down- and upstroke; the horseshoe-shaped vortexsubsequently grows into a doughnut-shaped vortex ring withan intense jet-flow present in its core,forming a downwash.The doughnut-shaped vortex rings of the wing pair eventu-ally break up into two circular vortex tings as they propagatedownstream in the wake.The aerodynamic yawing and roll-ing torques are canceled out due to the symmetric wing kine-matics even though the aerodynamic pitching torque showssignificant variation with time.On the other hand,the time-varying the aerodynamics pitching torque could make thebody a longitudinal oscillation over one flapping cycle.
Numerical investigation of vortex dynamics in wake-up of a hovering hawkmoth and hovering aerody-namics is conducted to support the development of abiology-inspired dynamic flight simulator for flapping wing-based micro air vehicles. Realistic wing-body morphologies and kinematics are adopted in the numerical simulations The computed results show 3D mechanisms of vortical flowstructures in hawkrnoth-like hovering. A horseshoe-shaped primary vortex is observed to wrap around each wing during the early down- and upstroke; the horseshoe-shaped vortexsubody grows into a donut-shaped vortex ring withan intense jet-flow present in its core, forming a downwash.The donut-shaped vortex rings of the wing pair eventu-ally break up into two circular vortex tings as they propagatedownstream in the wake. aerodynamic yawing and roll-on torques are canceled out due to the symmetric wing kine-matics even though the aerodynamic pitching torque showssignificant variation with time. On the other hand, the time-varying the aerodynamics pitching torque could make the body a longitudinal oscillation over one flapping cycle.