風車尾流效應之實驗研究

Experimental Study of the Wind Turbine Wake

江培宏(Pei-huhg Chiang)

指導教授 ： 朱佳仁

國立中央大學/工學院/土木工程學系/碩士(2007年)

摘要

本研究以風洞實驗的方式研究垂直軸式和水平軸式風車的特性，研究內容可分成兩個部份：第一部分探討垂直軸式風車在穩態風場、陣風風場與柵網紊流三種不同的來流風場中的發電情形，研究結果顯示：垂直軸式風車於陣風風場及柵網紊流風場中發電量與穩態風場中相近，故紊流強度的變化對於垂直軸式風車的發電量並沒有顯著的影響。第二部份則在穩態風場及柵網紊流中量測下水平軸式風車的尾流流速剖面，發現量測得之尾流風速在各下游距離皆呈現自我相似的特性，但穩態風場和柵網紊流的風車尾流會有所不同，並找出風車尾流的流速剖面公式。最後利用風車尾流的流速頻譜研究風車後方的渦流逸散現象，發現渦流逸散頻率的史徹荷數為0.2。

關鍵字

渦流逸散 ； 尾流 ； 風洞實驗 ； 風車

並列摘要

This experimental study used a large-scale atmospheric boundary layer wind tunnel to investigate the characteristics of horizontal axis and vertical axis wind turbines. The first part, the output powers of vertical axis wind turbine in three different approaching flows, namely, steady flow, periodically gusty flow and grid-generated turbulent flow are measured and the results are almost the same. The second part, the velocity distribution behind a horizontal axis turbine in steady flow and grid-generated turbulent flows are measured. The experimental results demonstrate the turbine wake show the self-similar behavior and can be predicted by equations. Lastly, the velocity spectra of turbines wakes are used to examine the vortex shedding of turbine and the Strouhal number is 0.2.

並列關鍵字

wind turbine ； vortex shedding ； wake flow ； wind tunnel experiment

參考文獻

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