本研究旨在比較固定入流與週期性入流條件下微型風力發電機的性能和尾流特性。在風力發電領域中，過去的研究主要集中在固定入流條件下的研究，然而，考慮到現實生活中風速的不穩定性，本研究將注意力轉向了週期性入流條件下的性能研究。通過風洞實驗進行了深入的研究。首先，我們調整了風機迴路中的負載電阻以改變風機的角速度，以實現不同的扭轉比（TSR）。通過分析不同TSR下的風機性能，我們得出了在特定TSR條件下達到最佳發電效率的結論。這一結果對於優化風機設計和運營具有重要意義。接下來，我們使用PIV（粒子圖像測速）技術測量了在具有最佳發電效率的TSR條件下的風機尾流。通過分析流向速度分佈、動量通量分佈和紊流強度分佈，我們對尾流特性進行了深入研究。研究結果顯示，在無因次化平均流向速度分布上，固定入流與週期性入流結果一致性良好。然而，週期性入流的動量通量與紊流強度因重疊原理會高於固定入流。當我們將因週期性入流的波所造成的影響扣除後，週期性入流能夠與固定入流達到相似的結果，這一發現對於風洞測試的準確性和可靠性具有重要意義。

The aim of this study is to compare the performance and wake characteristics of a miniature wind turbine under constant inflow and periodic inflow conditions. In the field of wind power, previous research has mainly focused on studies conducted under constant inflow conditions. However, considering the realistic variability of wind speeds in real-life situations, this study shifts its focus towards investigating the performance under periodic inflow conditions.
Initially, the rotational speed of the turbine was adjusted by varying the load resistance in the turbine circuit to achieve different Tip Speed Ratios (TSR). By analyzing the turbine performance at different TSR values, conclusions were drawn regarding the optimal power generation efficiency achieved under specific TSR conditions. These findings hold significant implications for the optimization of wind turbine design and operation.
Subsequently, we employed Particle Image Velocimetry (PIV) technology to examine the wake dynamics of the wind turbine under conditions that corresponded to the optimal TSR for power generation. An in-depth investigation of wake characteristics was conducted by analyzing the distributions of streamwise velocity, momentum flux, and streamwise turbulence intensity. The findings revealed that under normalized mean streamwise velocity distributions, the outcomes of constant and periodic inflow conditions exhibited a significant degree of consistency. However, the momentum flux and streamwise turbulence intensity in periodic inflow exceeded those in fixed inflow due to the principle of superposition. Notably, when we subtracted the effects caused by the oscillations of the periodic inflow, the outcomes of the periodic inflow closely mirrored those of the fixed inflow. This crucial finding significantly enhances the accuracy and reliability of wind tunnel tests by demonstrating that comparable results can be obtained under periodic and constant inflow conditions once the wave-induced effects are properly accounted for.

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