三維度紊流大渦模擬在多區間建築物室內環境風場之應用研究

Applications of Three-Dimensional Large-Eddy Simulations on Indoor Airflow Field of Multi-Room Buildings

謝怡芳(Yi-Fang Hsieh)

指導教授 ： 張倉榮

國立臺灣大學/生物資源暨農學院/生物環境系統工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.00846

摘要

本研究之主要目的為建立三維度多區間建築物環境風場紊流模式，以研析室內多區間三維度環境風場之時間平均流速、壓力及瞬時流速、壓力，以求能詳盡地分析具多重隔間複雜紊流場的流況。本研究採用有限體積法(finite volume method)離散控制方程式，以SIMPLE法耦合速度及壓力，使得整個流場符合質量守恆及動量守恆，再以大渦模擬(large eddy simulation，LES)紊流模式，結合亞格點尺度應力模式(subgrid scale stress model，SGS)來模擬紊流流場。
模式模擬結果首先透過與風洞試驗數據的比對，發現兩者相當吻合。本研究繼而針對台灣較為常見之三維度室內多區間案例，以不同通風策略進行模擬，窗戶開口開關方式分為全開通風、兩側通風、貫穿通風、交叉通風(型一及型二)及單側短路通風(型一及型二)等七種方式。同時亦針對室內無隔間案例作模擬，以進行室內無隔間案例與室內多區間案例之分析比較。模擬結果發現背風面區間換氣情況以貫穿通風案例為所有案例中之較佳情況，而室內區間通風情況直接受到其所屬之窗戶開口開關情況影響。
另一方面，綠植栽(孔隙介質)常被應用於降低風速、改善氣候及環境條件與增加作物產量等，因此本研究亦針對室內綠植栽(孔隙介質)對室內環境風場之影響進行探討，結果發現在研究案例中，綠植栽可有效的降低入流氣流25%之速度。

關鍵字

計算流體力學 ； 多區間建築物環境風場 ； 有限體積法 ； 綠植栽(孔隙介質) ； 大渦模擬紊流模式

並列摘要

The main objective of this study is to develop a 3-D turbulent flow model for indoor multi-room environment. The 3-D turbulent flow model of an indoor multi-room building in this study can provide not only mean flow field but also instantaneous flow field. The results enable us to understand indoor turbulence which cannot be given by the mean flow field. We select the finite volume method to discretize the governing equations of our model. SIMPLE scheme is used to adjust flow field to satisfy the continuity equation. Large eddy simulation(LES) with subgrid-scale stress model(SGS) is adopted to model the turbulence flow field in the study.
The numerical model is firstly verified by the reliable experimental measurement. The numerical results are in good agreement with the experimental data. In our case study, a common multi-room style in Taiwan region has been selected to simulate the flow patterns for various ventilation strategies in multi-room buildings. Seven kinds of ventilation strategies are simulated, including full-open ventilation, side ventilation, pass-through (piston) ventilation, cross ventilation(typeⅠand typeⅡ) and short-cut ventilation(typeⅠand typeⅡ). It is found out that pass-through ventilation can provide the most effective way in the downward-side rooms. The openness of windows in the room is the key point of ventilation efficiency. In addition, shelterbelts (porous media) situated in front of windows are used to reduce wind speed. The flow patterns changed by shelterbelts are discussed. Results show that shelterbelts can decrease indoor air speeds effectively up to 25%.

並列關鍵字

shelterbelts (porous media) ； Computational fluid dynamics ； multi-room building environmental flow field ； large eddy simulation ； finite volume method

參考文獻

高宏名，2004。「以三維度微粒軌跡追蹤模式研析多區間建築物室內懸浮微粒傳輸行為」，國立台灣大學生物環境系統工程學研究所碩士論文。

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