Velocity Field around a Rigid Flapping Wing with a Winglet in Quiescent Water


  • Srikanth Goli Department of Aerospace Engineering, Indian Institute of Technology, Kharagpur, West Bengal, India
  • Arnab Roy Department of Aerospace Engineering, Indian Institute of Technology, Kharagpur, West Bengal, India
  • Subhransu Roy Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur, West Bengal, India



square wing, flapping motion, winglet, one-degree-of-freedom flapping, PIV, velocity field


This study investigated the effect of a winglet on the velocity field around a rigid flapping wing. Two-dimensional particle image velocimetry was used to capture the velocity field of asymmetric one-degree-of-freedom flapping motion. A comparison was conducted between wings with and without a winglet at two flapping frequencies, namely 1.5 and 2.0 Hz. The effect of the winglet on the velocity field was determined by systematically comparing the velocity fields for several wing phase angles during the downstroke and upstroke. The presence of a winglet considerably affected the flow field around the wingtip, residual flow, and added mass interaction. The added mass was lower and residual flow was weaker for the wings with a winglet than for the wings without a winglet. The added mass and velocity magnitudes of the flow field increased proportionally with the flapping frequency.


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How to Cite

S. Goli, A. Roy, and S. Roy, “Velocity Field around a Rigid Flapping Wing with a Winglet in Quiescent Water”, Adv. technol. innov., vol. 5, no. 4, pp. 259–269, Sep. 2020.