鄰近高樓影響下之建築物風壓通風

Wind-driven Cross Ventilation under the Influence of an Adjacent Large Building

游向芸(Xiang-yun You)

指導教授 ： 朱佳仁

國立中央大學/工學院/土木工程學系/碩士(2015年)

摘要

自然通風對建築設計上扮演這相當重要的角色，利用建築物外部與內部之間的壓力差異使得空氣流通，可減少對機械通風的依賴，節約能源。而在都會地區許多建築緊密相鄰，因此空氣較不易流通，即使有門窗開口，仍有通風不良的狀況。本研究使用大渦流數值模式研究受周遭其他建築物影響的建築物表面風壓及通風量。探討的參數包括建築物的大小、間距及排列方式。研究結果顯示：當兩棟建築物之間的距離大於兩倍主建築物高度時，主建築物的通風量就不受鄰近建築物的影響。而當下風處鄰近建築物的寬度及高度越大，上風處主要建築物通風量越小。研究發現鄰近建築物的寬度對主建築物通風的影響很大，當下風處鄰近建築物寬度為主建築物寬度兩倍時，主建築物背風面的風壓係數會大於迎風面的風壓係數，造成逆向通風之現象。此研究並發現主建築物位於鄰近建築物後方時，鄰近建築物的高度越高，遮蔽效應越明顯，主建築物通風量越小，且主建築物背風面的風壓係數皆高於迎風面的風壓係數，因此皆有逆向通風現象產生。

關鍵字

自然通風 ； 風壓通風 ； 風壓係數 ； 大渦模擬 ； 阻滯效應

並列摘要

In densely-populated areas, where buildings are grouped closely together, wind-driven ventilation is strongly influenced by the surrounding buildings. The sheltering effect of the surrounding built-up environment can reduce the wind speed and wind-driven ventilation rate. This study used a three-dimensional Large Eddy Simulation (LES) model to investigate the influences of adjacent building on wind-driven natural ventilation of a pitched-roof building. The influences of building height, width and spacing between the buildings were systemically studied. The results demonstrate that the influence of the adjacent building on the ventilation rate of the pitched roof building becomes insignificant when the spacing S  2.0He. The leeward pressure is larger than the windward pressure when the building width Wb/Wu = 2.0. In other words, the air flow will enter the building from the leeward opening and exit through the windward opening. Furthermore, when the pitched roof building is behind a tall flat-roof building, due to the sheltering effect, the ventilation rate of the pitched roof building is significantly reduced with the increasing height of the flat-roof building.

並列關鍵字

Wind-driven cross ventilation ； Pressure coefficient ； Computational Fluid Dynamics ； Large Eddy Simulation ； Sheltering effect ； Pitched roof

參考文獻

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