Numerical Investigation of Aerodynamic Characteristics by a Rotating Thin Plate

Yoshihiro Kubota^1*, Osamu Mochizuki²

¹Faculty of Science and Engineering, Toyo University, Kawagoe, Japan.
²Department of Biomedical Engineering, Toyo University, Kawagoe, Japan.

DOI: 10.4236/wjm.2015.53005                

Abstract

In this study, we use a thin rotating plate to generate propulsion and lift for a paper plate. And the thin plate rotates along the spanwise axis. We numerically determine the influence on aerodynamic characteristics with a rotational velocity of the thin plate. The rotational velocity is obtained with spin parameter which is the ratio of the peripheral speed of the plate to the main flow velocity. And the numerical simulations based on the discrete vortex method show that the autorotation mode of the plate in a uniform flow appears naturally when the spin parameter is unity. Vortex formed from the backward-rotating edge is weaker than those generated from the forward-rotating edge of thin plate. The maximum lift generated at S = 0.75 if S < 1. The negative moment becomes negative for the nondimensional rotating speed S ≤ 1.75. The most negative moment appears when S = 1; at that time, autorotation occurs naturally.

Keywords

Autorotation, Thinplate, Vortex, Vortexmethod, Speed of Rotation, Spin Parameter

Conflicts of Interest

The authors declare no conflicts of interest.

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