多樓層建築物自然通風之實驗研究

Experimental Study of Natural Ventilation in Multi-Floor Buildings

王伯威(Po-wei Wang)

指導教授 ： 朱佳仁

國立中央大學/工學院/土木工程學系/碩士(2012年)

摘要

This study used wind tunnel experiments and tracer gas technique to investigate the natural ventilation of multi-floor buildings and buoyancy-driven ventilation and the natural ventilation with adjacent building. The ventilation rates and discharge coefficients of the vertical openings were measured by the tracer gas and fan techniques. The experimental results indicated that the buoyancy-driven ventilation rate increased as the height of the opening increased with single opening building. This study also found that the wind-driven natural ventilation was independent of the spacing between two models when the spacing over five times of building height if two identical building models were placed in a tandem arrangement. When two models was placed side-by-side, the surface pressure coefficient decreased as the lateral spacing increased. This study also explored the internal resistance of multi-floor buildings with staircase and found that the internal discharge coefficient is dependent on the opening size, but independent of external wind velocity. The internal discharge coefficient with staircase is smaller than that of without staircase by 11%. And the internal discharge coefficient does not change with the arrangement of the stair. The ventilation rates of multi-floor buildings can be predicted by the resistance model of Chu and Wang (2010). The wind-driven ventilation rate decreases as the number of floor increases. This model can provide architects to evaluate the ventilation rate and thermal comfort of nature ventilated buildings.

關鍵字

風洞實驗 ； 自然通風 ； 多樓層建築物

並列摘要

本研究採用風洞模型實驗的方式來研究有多樓層(Multi-floor)建築物的自然通風問題，實驗流況包括室內無隔間之熱浮力通風、室外有相鄰建築物之風壓通風及多樓層建築物的風壓通風。實驗採用示蹤劑濃度衰減法來量測熱浮力通風之通風量，利用噴嘴流量計量測不同樓層之間的流量係數。實驗結果發現建築物僅有單側開口時，開口愈高，浮力通風產生的通風量會愈大。風壓與熱浮力同時作用下，視風向與開口高低位置而定，有時具有加成效果，通風量較大，有時則會互相抵銷，通風量變小。本研究亦發現當室外相鄰建築物前後並排時，下風建築物的表面壓力及風壓通風量會隨兩棟建築物間距離減少而變小。左右相鄰建築物間距縮小時，建築物之間的表面風壓會大於單棟建築物之側面風壓。本研究也探討室內多層樓與裝設樓梯間對室內通風的影響，結果發現室內不同樓層之間的流量係數接近同一樓層水平向開口的流量係數，同樣地與開口面積有關，且室外風速不會影響室內開口流量係數。實驗結果發現室內加裝樓梯會造成流量係數下降11%，改變室內樓梯的設置方式亦不會影響室內開口流量係數。受室內樓梯影響的通風量可用Chu and Wang (2010)的阻抗模式及阻抗因子加以預測，且樓層數愈多，通風量愈小。此模式可供建築設計者未來在評估、規劃建築物自然通風之用。

並列關鍵字

Multi-floor building. ； Natural ventilation ； Wind tunnel experiment

參考文獻

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