葉片曲率對垂直軸風力發電機性能之研究

Research on the Influence of Blade Curvature on the Performance of a Vertical-axis Wind Turbine Generator

曾柏勳(Po-Shun Tseng)

指導教授 ： 翁輝竹

中原大學/工學院/機械工程研究所/碩士(2012年)

https://doi.org/10.6840/cycu201200949

摘要

本論文完成垂直軸風力發電機性能之研究，目的在探討不同風速下，Savonius葉片曲率對其機械能源、電力能源及轉換效率之影響。首先，以鋁製薄板為製作材料，設計不同曲率半徑之S型葉片，接著藉由風洞測試系統之設置，以產生不同風力條件。並設計傳統型與合併型葉片，藉由風力發電機之架設與轉速、扭矩及發電功率之量測，以決定不同風速下，Savonius垂直軸風力發電機性能之數據。最後，流場情形以計算流體動力學軟體進行模擬分析，以了解問題成因。針對傳統型葉片，研究結果發現，在某一特定風速下，機械能源、電力能源及最高轉換效率皆隨著葉片曲率半徑增加而增加，然而上升至一極大值後便下降。此曲率效應可隨風速增加，而呈現增加的現象。針對合併型葉片，研究結果顯示，機械能源、電力能源及最高轉換效率皆因輔助葉片曲率半徑增加而增加。此曲率效應可隨風速增加，而呈現增加的現象。當輔助葉片具有較大的曲率半徑，此合併型垂直軸風力發電機相較於傳統型會有較佳的性能表現。

關鍵字

曲率半徑 ； Savonius葉片 ； 轉換效率 ； 風力能源 ； 垂直軸風機

並列摘要

This paper conducts a study on the performance of a vertical-axis wind turbine generator. The purpose is to investigate the influence of Savonius blade curvature on its mechanical energy, electrical energy, and conversion efficiency for different wind speeds. First, we present S-shaped blades of different curvature radii by using aluminum thin sheets. Second, we generate different wind conditions by setting a wind tunnel testing system. Also, we design both typical-type and combined-type blades first and then set up the wind turbine generator and measure the rotational speed, torque, and power generation, so as to obtain the Savonius vertical-axis wind turbine generator performance data at different wind speeds. Finally, we use a computational fluid dynamics software to simulate the flow fields, so as to realize the cause of the issue. For typical-type blades, it is found that when the value of the curvature radius increases at a fixed wind speed, all the mechanical energy, electrical energy, and highest conversion efficiency increase to their maxima and then decrease. The curvature effect can be magnified by increasing the wind speed. As for combined-type blades, results reveal that all the mechanical energy, electrical energy, and highest conversion efficiency increase as the curvature radius of an auxiliary blade increases. This effect also can be magnified by increasing the wind speed. One can notice that for a combined-type vertical-axis wind turbine generator with a greater auxiliary blade curvature radius, its performance is better than the typical-type one.

並列關鍵字

wind energy ； conversion efficiency ； vertical-axis wind turbines ； curvature radius. ； Savonius blades

參考文獻

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