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Vorticity transfer in a leading-edge vortex due to controlled spanwise bending

Kun Jia1, Tyler Scofield2, Mingjun Wei1, and Samik Bhattacharya2,*

  • 1Department of Mechanical and Nuclear Engineering, Kansas State University, Manhattan, Kansas 66506, USA
  • 2Mechanical and Aerospace Engineering Department, University of Central Florida, Orlando, Florida 32816, USA

  • *Corresponding author: samik.bhattacharya@ucf.edu
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Phys. Rev. Fluids 6, 024703 – Published 25 February, 2021

DOI: https://doi.org/10.1103/PhysRevFluids.6.024703

Abstract

Many natural flyers and swimmers routinely flex their lifting or propulsive surfaces to control the leading-edge vortex (LEV) that forms on the suction side during maneuvering at a high angle of attack. In this paper, we studied the effect of a similar bending on the vortex dynamics of a flat-plate airfoil of aspect ratio 3 (chord 5cm) and held at an angle of attack of 30∘. This flat plate is accelerated from rest to a Reynolds number of 2400, while being dynamically bent along the span in a controlled manner with a bending ratio of 0.65 and a maximum bending angle of 30∘. We investigated the effect of such spanwise bending on the resultant vorticity transfer via both experiments and numerical simulation. It shows that a dynamic spanwise bending induces a change in the effective shear layer velocity along the span's bent part and creates spanwise vorticity convection. As a result, the growth of circulation in the LEV gets delayed along the bent part, and the final circulation is smaller than the no-bending case.

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Outline

Information

Phys. Rev. Fluids 6, 024703– Published 25 February, 2021
  • Received 15 January 2020
  • Accepted 9 February 2021
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