| 研究生: |
李昆祐 Lee, Kun-Yu |
|---|---|
| 論文名稱: |
計算流體力學對雨屏牆等壓性能之初探 An Exploratory Study of Air Pressure Equalization in Rainscreen Wall by Using Computational Fluid Dynamics |
| 指導教授: |
黃斌
Huang, Pin |
| 學位類別: |
碩士 Master |
| 系所名稱: |
規劃與設計學院 - 建築學系 Department of Architecture |
| 論文出版年: | 2006 |
| 畢業學年度: | 94 |
| 語文別: | 中文 |
| 論文頁數: | 48 |
| 中文關鍵詞: | 計算流體力學 、雨屏牆 、等壓 |
| 外文關鍵詞: | rainscreen wall, FLUENT, CFD, pressure equalization |
| 相關次數: | 點閱:120 下載:2 |
| 分享至: |
| 查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報 |
雨屏牆運用於外牆改修上,可保留原有外牆以減少廢棄物產生,藉由透風孔導入外氣使雨屏內外達成等壓,可防止水的入侵和減輕風載,中空層內空氣亦有隔熱之效,為一符合永續建築概念之外牆構法。
本研究最主要之目的為探討-運用計算流體力學(CFD)研究雨屏牆等壓性能之可行性,從計算流體力學之認識開始,依循數值模擬之流程,測試不同劃分網格方法與FLUENT軟體內不同之數值模型,經由風洞實驗值初步回饋修正,最後再導入參數-中空層厚度,以產生較大量之比對數據,經由定性和定量的分析評估其可行性。
本研究選擇點支撐構法與縫寬10mm之開放式接縫雨屏牆,比較之中空層厚度5cm~20cm,比較之風速為8m/s和19m/s,研究成果如下:
一、數值模擬計劃
1. 包圍接縫之網格,使用結構網格明顯比非結構好。
2. 接縫內之網格愈密,總網格數愈多,模擬結果愈準確,但過密會出現無法收斂之問題。
3. 本研究比較紊流模型為標準k-ε、RNG k-ε和Reliable k-ε,以標準k-ε最接近實驗值。
二、模擬值和實驗值之比較
1. 兩者均具有:1.等壓效果、2.雨屏表面壓力比雨屏背面大(減壓)、3.中空層內各點壓力相近(非常吻合) 等相似行為。
2. 通過接縫時,模擬值減壓的幅度比較小,因此雨屏表面和背面之壓差較小故△Cp較小。
3.風速8m/s和19m/s時,△Cp差值均介於3%~4%之間,符合文獻指出應在5%以內,因此本研究認為運用CFD研究雨屏牆等壓性能是可行的。
綜上所述,CFD能夠準確地預測定性,但定量上還存在若干差值需作修正,若應用於定性討論,輔助風洞實驗,預先篩選以減少實驗項目,將可有效減少時間與金錢之花費。
The rainscreen wall system can prevent the invasion of water, reduce the wind load and insulate against heat by air pressure equalization, so it conforms to the sustainable architecture concepts.
The main purpose of this paper is to study the practicability of using CFD on air pressure equalization in rainscreen wall. Beginning with understanding CFD, this paper tested different mesh ways and numerical models, and initially corrected the simulated data with experimental. Finally, putting in the parameter-the depth of cavity–produced more comparable data and evaluated the practicability via qualitative and quantitative analysis.
This paper chooses point-support and open-joint(width=10mm) rainscreen wall system for research. The compared depth of cavity are 5~20cm, and wind speed are 8m/s and 19m/s. The results are as followings:
一、Numerical model plan
1. Considering the mesh surrounding the open-joint, structural grids are better than unstructured.
2. More grids in the open-joint will make the result more accurate, but over-density will lead to un-convergence.
3. To compare with stand k-ε、RNG k-ε and Reliable k-ε, stand k-εis the most accurate.
二、Comparison with CFD and wind-tunnel data
1. Similar behavior:1. pressure equalization、2. Pro is higher than Pri、3.all values in the cavity are nearly the same.
2. The △Cp of CFD is lower than wind-tunnel.
3. △Cp difference of CFD and wind-tunnel are all between 3%~4% and within 5% which reference refers to, so using CFD on air pressure equalization in rainscreen wall is practicable.
C1 「中國文化大學城區部增建工程」,台灣建築雜誌,pp.12-19,2001.8
C2 朱佳仁,工程流體力學,科技圖書,台北,2005
C3 朱佳仁,風工程概論,科技圖書,台北,2006
C4 周伯丞等人,貼體格點系統技術之運用,能源與冷凍空調學術研討會,2004
C5 林政彥,Fluent Basic Training Course,國家高速網路與計算中心,2006
C6 邱瓊萱,通風管管頂型式對室內通風效益影響之研究,成大建築研究所碩論,台南,2004
C7 陳兆華,風攻角對雨屏牆等壓性能之研究,成大建築研究所碩論,台南,2005
C8 蔡健雄等人,格點系統與紊流模式之影響,能源與冷凍空調學術研討會,2004
C9 鄭佳欣,雨屏透風孔幾何形狀對雨屏牆等壓性能之研究,成大建築研究所碩論,台南,2005
C10 謝曉星,計算流體力學及熱傳學,高立圖書,台北,1993
E1 A. Baskaran,A Numerical Model to Evaluate the Performance of Pressure Equalized Rainscreen Walls,Building and Environment,Vol.29,pp.159-171,1994
E2 A. Baskaran,Prediction of Wind Effects on Building Using Computational Methods-State of the Art of Review,Canadian Journal of Civil Engineering 21,pp.805-822,1994
E3 Computational Fluid Dynamics and Double Skin Facades,Chris Champagne
E4 FLUENT HELP,Fluent Inc.,2006
E5 FLUENT Training PowerPoint,2006
E6 GAMBIT HELP,Fluent Inc.,2006
E7 K. Suresh Kumar,Prediction of pressure equalization performance of rainscreen walls,Wind and Structures,Vol.2 No.4,pp.325-345,1999
E8 K. Suresh Kumar,Pressure Equalization of Rainscreen Walls:a Critical Review,Building and Environment,Vol.35,pp.161-179,2000
J1 S. Murakami,Overview of Turbulence Models Applied in CWE-1997,2nd European & African Conference on Wind Engineering,1997
J2 S. Murakami,Current status and future trends in computational wind engineering,Wind Engineering an Industrial Aerodynamics67&68,pp.3-34,1997
J3 川端三郎,風と外裝材,建築技術,1994