近年來隨著政府積極地推動太陽能發電，各地設置於建築物屋頂或地面的太陽光電系統日益增多，而為了確保太陽光電系統能有一定的耐風安全性，許多學者開始對其進行研究，主要利用風洞實驗或計算流體力學(CFD)模擬其受風特性，並制定出相關規範。
本研究利用LES紊流模型，並以非穩態的方式進行求解，針對地面型太陽能面板進行模擬分析；其中，面板傾角為10度或25度，來風方向為0度或180度。模擬後之結果與風洞實驗資料進行比較，包含風壓係數與淨風壓係數，以驗證模擬的準確性。由於本研究模擬風壓歷時之長度不足以進行極值分析，因此僅分析淨風壓係數歷時及風力係數歷時之機率分布及頻譜，初步探討以LES結果進行極值分析之可行性。此外，本研究亦比較其他紊流模型，以探討使用不同紊流模型模擬結果之間的差異。
本研究結果發現，LES相較於SST k-ω紊流模型，整體結果較為準確。雖然模擬之太陽能板模型未考慮面板下支撐柱，而風洞實驗模型於面板下方有密集的風壓測管分布，使得在來風方向0度或180度時，模擬結果之淨風壓係數普遍略高於實驗值，但機率分布與頻譜之結果大致與實驗值相符，因此預期未來利用LES模擬結果進行極值分析後應可得到合理的極值。此外，本研究發現CFD在模擬分析上的幾項優勢：1.能展現較為完整的流場資訊及面板上之風壓分布；2.可依據實場建立無縮尺模型，並進行與真實情況較為相符之模擬分析；3.模擬結果可避免實驗儀器精度不足或實驗儀器配置之限制。

In recent years, as the government has actively promoted solar power generation, more solar photovoltaic systems are installed on the ground or building roofs. In order to ensure that the solar photovoltaic systems are safe under wind, many scholars have begun to use wind tunnel experiments or Computational Fluid Dynamics(CFD) to study their wind characteristics and formulate relevant specifications.
In this study, ground-mounted solar panels are simulated by Large Eddy Simulation(LES) model, and the unsteady solutions are obtained. The CFD models with panel inclination angles of 10° and 25° are established, and wind directions of the incoming flow are 0° and 180°. The simulation results are compared with the experimental data, including wind pressure coefficients and net wind pressure coefficients, to verify the accuracy of the simulation results. However, the simulation duration in this study is not sufficient for extreme value analysis. Therefore, this study only verifies the probability distributions and spectra of net wind pressure coefficients and wind force coefficients. In addition, LES results are also compared with those of SST k-ω model.
In general, LES yields more accurate results than SST k-ω turbulence model. Although this study uses a simplified solar panel model, and the wind tunnel experimental model has many measuring tubes under the panel, it is found that the simulated net wind pressure coefficients are generally larger than the experimental values whether the wind direction is 0° or 180°. The simulation based probability distributions and frequency spectra are roughly in line with the experimental results, and it is expected that reasonable extreme values would be obtained when the simulation time is sufficient. In addition, this study finds several advantages in CFD：1.It can display more complete flow field information and wind pressure distribution on the panel. 2. A scale-free model simulation can be carried out in CFD. 3. The limitation of the experimental instrument configuration can be released in CFD.

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