Wake-foil interactions and energy harvesting efficiency in tandem oscillating foils

Bernardo Luiz R. Ribeiro, Yunxing Su, Quentin Guillaumin, Kenneth S. Breuer, and Jennifer A. Franck
Phys. Rev. Fluids 6, 074703 – Published 26 July 2021

Abstract

Oscillating foils in synchronized pitch/heave motions can be used to harvest hydrokinetic energy. By understanding the wake structure and its correlation with the foil kinematics, predictive models for how foils can operate in array configurations can be developed. To establish a relationship between foil kinematics and wake characteristics, a wide range of kinematics is explored in a two-foil tandem configuration with interfoil spacing from four to nine chord lengths separation and multiple interfoil phases. Using data from experiments and simulations, an in-depth wake analysis is performed and the mean velocity and the turbulent kinetic energy are quantified in the wake. With this energy quantification, the trailing foil efficiency is modified to account for the mean flow in addition to the energy transported by the coherent leading edge vortices (LEVs) shed from the leading foil. With the mean wake velocity, a predictive wake model is able to distinguish three regimes through analyzing trailing foil efficiency profiles and the strength of the primary LEV shed from the leading foil. Dividing the wake into regimes is an insightful way to narrow the range of foil kinematics and configurations and improve the energy harvesting in a two-tandem foil array.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
14 More
  • Received 12 March 2021
  • Accepted 7 June 2021

DOI:https://doi.org/10.1103/PhysRevFluids.6.074703

©2021 American Physical Society

Physics Subject Headings (PhySH)

Fluid Dynamics

Authors & Affiliations

Bernardo Luiz R. Ribeiro

  • Department of Engineering Physics, University of Wisconsin—Madison, Madison, Wisconsin 53706, USA

Yunxing Su, Quentin Guillaumin, and Kenneth S. Breuer

  • Center for Fluid Mechanics, School of Engineering, Brown University, Providence, Rhode Island 02912, USA

Jennifer A. Franck

  • Department of Engineering Physics, University of Wisconsin—Madison, Madison, Wisconsin 53706, USA

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 6, Iss. 7 — July 2021

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Fluids

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×