Effects of Porosity on Wind Driven Natural Cross Ventilation of a Full Scale Building

在完整尺度建築下風力驅動通風之多孔效應研究

班夏禮(M. Z. I. Bangalee) ； 林三益(S. Y. Lin) ； 苗君易(J. J. Miau)

《中國機械工程學刊》 37卷4期 (2016/08) Pp. 305-313

摘要

本研究數值於探討建築物自然通風之效率問題。在一定風速下，探討窗戶開口比例，對窗戶之平均速度大小的影響。首先使用計算流體軟體模擬一個建築物自然通風之流場，並和實驗的結果相互驗證。吾人使用正規化紊流模型可以得到良好的驗證。其次分析不同開口比例的通風效率。吾人發現百分五之開口比例，可以得到最佳之通風效率。在不同雷諾數下，此通風效率亦有相同結果。

並列摘要

Natural ventilation for thermal comfort to the occupants can be achieved if the buildings are designed in favor of the available wind direction and wind force. The replacement of any mechanical ventilation system not only saves the electric cost but also reduces the pollutants what are generated during the electricity production stage. The effects of porosity on the Wind Driven Natural (WDN) cross ventilation of a full scale building has been investigated using the Computational Fluid Dynamics (CFD) technique. The numerical methodology has been validated through a satisfactory comparison with an experimental work. The Renormalization Group k-ε (RNG) turbulence model has been applied to capture the turbulence accurately. The porosity effects have been completely analyzed and it is found that the efficiency (66%~74%) of the ventilation system depends on porosity (1% to 30%) whereas the maximum efficiency is obtained at 5% porosity. The ventilation phenomenon is found Reynolds number independent.

並列關鍵字

WDN ventilation ； Porosity ； CFD ； RNG k-ε