Efficient cruising for swimming and flying animals is dictated by fluid drag

Abstract

Almost 30 y ago, researchers discovered that a great variety of efficient swimmers cruise in a narrow range of Strouhal numbers, a dimensionless number describing the kinematics of swimming. Almost 15 y later, separate researchers discovered that fliers (bats, birds, and insects) also cruise in the same narrow range of Strouhal numbers. Attendant experiments on flapping airfoils have shown that this narrow range of Strouhal numbers gives rise to the most efficient kinematics. Here, we explain why this range of Strouhal numbers is the most efficient.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 18, 2018
Source ID
10.1073/pnas.1805941115

Entities

People

  • Alexander Smits
  • Daniel Floryan
  • Tyler Van Buren

Organizations

  • Office of Naval Research
  • Princeton University

Tags

Fields of Study

  • Physics

Readers

  • Aquatic Ecology
  • Fluid Mechanics and Fluid Dynamics.
  • Systems Analysis and Design