A Study on Stack Effect and Natural Ventilation in Atriums

本报告的目的是调查冬季引起中庭热不适的堆叠效应，以及在秋季对中庭空间进行整体降温的自然通风，或在夏季对靠近玻璃屋顶的中庭顶部的热空间进行降温的自然通风。1.对某高层写字楼附设的中庭的热环境和空气流动进行测量分析：中庭整体覆盖玻璃。夏天，中庭顶部的空气温度会上升到60ﾟC，热玻璃屋顶表面的辐射会造成热不适。中庭顶部的自然通风是非常重要的。冬季，大量室外空气通过出入口流入中庭，导致中庭内空气温度下降。2.室外气流流向电梯井和电梯井漏风口的分析：通过对室外、中庭、电梯厅和电梯井的压力测量，估算了由于堆叠效应而进入电梯井的风量。3.通过收集文献和向设计人员发放问卷对已建成的玻璃覆盖建筑进行调查：对文献中记载的约500个中庭进行分析，以调查中庭在空间类型、空间高度、建筑面积、玻璃面积、空间使用等方面的变化趋势。通过对中庭设计人员的问卷调查分析，明确了目前流行的热环境控制方法，包括自然通风和抑制由堆叠效应引起的室外气流进入中庭。

The purpose of this report is to investigate stack effect which causes thermal discomfort in atriums in winter seasons and to investigate natural ventilation which cools overall the atrium space in autumn seasons or cools the hot space at the top of atrium near the glass roof in summer seasons.1.An analysis of thermal environment and air movement measured in an atrium attached a high-rise office building : This atrium is overall covered with glasses. In summer, the air temperature at the top of the atrium increases until 60ﾟC and radiation from the hot glass roof surfaces causes thermal discomfort. Natural ventilation at the top of the atrium is very important. In winter, a large amount of outdoor air flows into the atrium through entrance openings and causes air temperature decrease in the atrium.2.An analysis of the air flow from the outdoor to the elevator shafts and the leakage tactors of the elevator shafts : Air flow rate into the elevator shafts caused by stack effect is estimated using measurements of pressure at the outdoor, the atrium, the elevator hall and the elevator shafts. The leakage factors of elevator shafts are estimated too, using measurements.3.An investigation of already constructed glass-covered architectures from collecting literature and from sending out questionnaires to designers : About 500 atriums recorded in the literature are analyzed for the purpose of surveying the tendency of space type, space height, floor area, glass area, space use etc. An analysis of the questionnaire reply from the atrium designers makes clear popular controll methods of thermal environment involving natural ventilation and restraint of out door air flow into atriums caused by stack effect.