Performance Improvement and Formulation of Drag-typed Vertical Axis Wind Turbine with Sailcloth Blades at Low Wind Speeds by Controlling Blade Shape

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K12270
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 64050:Sound material-cycle social systems-related
• Research Institution: Hirosaki University
• Principal Investigator: Kubota Takeshi 弘前大学, 地域戦略研究所, 准教授 (70400405)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 垂直軸風車 / 帆布翼 / 空力性能 / 数値流体計算

Outline of Final Research Achievements

This research aimed to improve the aerodynamic performance of an 8-blade vertical-axis wind turbine, and as a result of the investigation using both experiments and numerical calculations, it was found that in the typical turbine with a straight 8-blade, the jet flow (accelerated flow) into the wind turbine contributes to the rotational force, and that that flow is generated by the blade generating the inverse-rotational force.
By adjusting the shape of soft sail cloth blades with deformability to control the flow, the performance of the wind turbine can be increased by approximately 20 % was confirmed.
At the same time, the problem that 2D-CFD calculations cannot represent experimental results plausibly due to the specifications of the wind turbine was also investigated, it was found that that problem can be handled by arithmetic post-processing.

Free Research Field

風車工学

Academic Significance and Societal Importance of the Research Achievements

柔軟な帆布を翼とする垂直軸の抗力型風車において、ギアのような部品を使うことなく受風時の風の力だけで翼形状を制御する設計によって、固定翼風車と比して取り出せる出力を約20%向上、あるいはより低速から始動する仕様を見出した。これによりエネルギーとして利用しにくい地上付近（低層）の低風速でも風車利活用の可能性を高めた。また、充填率の高い風車に対する2次元数値流体計算（CFD）の結果が3次元構造体である実際の風車における実験値と合わないことについて考察、長大な時間を要する3次元CFDをせずとも2次元CFD結果に比較的簡便な後処理を施すだけで実機の性能をおよそ予測できるとの工学的に有用な知見を得た。