湿热气候下民居天井空间的气候适应机制研究

THE CLIMATE RESPONSIVE MECHANISM OF COURTYARD DWELLINGS IN HOT-HUMID CLIMATE

湿热气候下,采用天井式院落布局具有重要的气候调节意义,文章通过建筑物理环境测试手段,对渝东南地区典型天井式民居的气候适应性机制及有效程度进行了验证。研究发现:天井空间对白天空气温度峰值的削减作用显著;在夜间或室内有采暖的条件下,能一定程度上减缓热量散失。同时,通过实测及计算分析发现,此类天井的作用机制不能简单解释为热压驱动下的"拔风"作用,但天井在热压作用下的通风依然有意义,在其作用方向上可将天井底部较低温度的空气经由房间内部流向室外。并且与同等体量的大进深建筑相比,在中部设置天井是保证室内自然通风的有效手段。

In hot-humid climate, courtyard has signifi cances to modify the indoor microclimate. In this paper, several fi eld investigations and measurements are conducted in a typical courtyard vernacular dwel ing of the southeast of Chongqing and its climate responsive mechanism and effectiveness are verifi ed. The study fi nds that the peak air temperature during the day has decreased signifi cantly in and around the courtyard space. While during the night and heating period, the courtyard has slowed down the heat loss process to some extent. It also fi nds that the ventilation mechanism of the courtyard dwel ing can't be simply interpreted as 'air draft' driven by thermal pressure ventilation. In summer daytime, the air movement driven by thermal pressure in the courtyard is from the top to the bottom as the air movement driven by wind pressure is often from the opposite direction. Nonetheless, the thermal pressure ventilation is still meaningful for the courtyard dwel ing, for it can bring the cooling air from the bottom of the courtyard into the interior space nearby. And courtyard space is proven to be effective to assure indoor natural ventilation especially for buildings with large depth.