Experiment on basic performance of a simple waterwheel/windmill with a cross-stream axis

29th IAHR Symposium on Hydraulic Machinery and Systems

Sato, Hironobu^1 ; Tokiwa, Tomohiro^1 ; Mihara, Hiroaki^2 ; Noguchi, Takashi^3 ; Hirata, Katsuya^1

Department of Mechanical Engineering, Doshisha University, Kyoto

610-0321, Japan^1

General Building Research of Corporation of Japan, Kyoto

612-8464, Japan^2

Department of Aeronautics and Astronautics, Kyoto University, Kyoto

615-8246, Japan^3

关键词: Aerodynamic characteristics;    Finite flat plate;    Phase averaging techniques;    Power coefficients;    Simple structures;    Subsonic wind tunnels;    Synchronised measurements;    Torque coefficient;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/240/4/042019/pdf
DOI  :  10.1088/1755-1315/240/4/042019

来源: IOP

【 摘 要 】

We conduct subsonic wind-tunnel experiments, in order to investigate the basic aerodynamic characteristics of an autorotating finite flat plate in uniform mainstream, which has a potential for unconventional waterwheels and windmills with very simple structures in addition to unusual mixers/diffusers. The present study focuses on both the effects of an aspect ratio AR and a tip-speed ratio Ω∗ upon autorotation of the flat plate with a low thickness-to-depth ratio λ = 1.3×10-2 - 2.0×10-2. We carry out the measurements using a torquemeter together with the synchronised measurements of the plate's attack angle α for the analyses with phase-averaging technique. As a result, the (time-mean) torque coefficient CT TM tends to decreases with increasing Ω∗, and CT TM tends to become large with increasing AR. (Time-mean) power coefficient CP TM shows that the present phenomenon is suitable for low-speed waterwheels and windmills.