行政院國家科學委員會補助專題研究計畫成果報告:溫室通風動態模擬（一）

本研究使用計算流體動力學 (Computational Fluid Dynamics, CFD)進行自 然通風低層建築物通風效率之分析。首先， 以紊流大渦模擬模式(Large Eddy Simulation, LES)配合Navier-Stokes 控制方程式，進行 CFD數值環境風場模式的研究發展，繼而將 數值模擬結果與現有風洞實驗資料進行比對 分析，以驗證數值模式之參數，其結果發現 十分吻合。本研究再跟文獻中CFD 最常見之 紊流k-ε模式模擬結果比較，比較結果顯示 LES 模式具有非等向性渦漩模擬之優越性， 優於紊流k-ε模式，尤其是在角隅及屋頂部 位，k-ε模式所得之結果與實驗值差距更 大。最後，本研究對單區間雙斜式溫室，予 以通風數值模擬測定，對不同位置及角度之 開口做有效性之室內通風路徑組合，嘗試以 既有之溫室通風控制模式作為基礎，尋求室 內通風路徑之最佳化方式，以獲得有效率、 可靠的通風設計資料，並作為工程師設計參 考之依據。A systematic analysis of the ventilation process in naturally ventilated low-rise buildings was performed with the use of computational fluid dynamics (CFD) to solve the Navier-Stokes equations together with the large eddy simulation (LES) turbulence model. The validity of the model was verified by comparing the simulated numerical results with the published experimental data and the conventional turbulence model such as the k-ε model. A good agreement between the numerical data and the experimental measurements was found if a LES turbulence model is applied in CFD simulation, especially for the flow fields located in the corners and top of the buildings. Then, the influence of design characteristics, such as the opening angles and locations on the ventilation efficiency was examined in the case of a typical Venlo greenhouse, which is a representative example of naturally ventilated low-rise buildings. It is demonstrated that CFD is a powerful tool for developing improved designs with respect to ventilation efficiency