天津办公建筑空间设计因素节能分析与优化

为改善天津地区办公建筑空间节能效果,以点式高层办公楼为例,研究空间设计因素对建筑能耗的影响及优化节能设计方案.首先基于案例调研总结其空间设计因素的典型值或值域,建立典型模型;然后选择6项空间设计因素展开分析,包括平面长宽比、建筑朝向、标准层面积、层高、窗墙比、外窗水平遮阳板长度,依次通过正交试验和列表法安排DesignBuilder能耗模拟试验,从而很快地获得优化节能设计方案.模拟试验考虑两种围护结构构造类型,分别代表常规构造和被动房构造.试验结果表明:层高与窗墙比构成建筑能耗的两项重要影响因素,其次为标准层面积、平面长宽比与建筑朝向、外窗水平遮阳板长度;优化节能设计方案中各因素的取值为:平面长宽比2∶1,建筑朝向南向,标准层面积1 024 m~2,层高3.6 m,窗墙比0.3,外窗水平遮阳板长度300 mm.经过试验设计与模拟分析,实现天津地区点式高层办公楼空间节能效果最大化,为该地区办公建筑节能设计提供参考.

Energy saving analysis and optimization of geometric factors of office buildings in Tianjin

To improve energy saving efficiency of Tianjin office buildings, we select high-rise office tower as an example and assess the effect of geometric factors on building energy performance, also identify the most energy-efficient geometric design. A prototype model is established based on survey data. We choose 6 geometric factors according to previous studies: plane aspect ratio (length to width), orientation, floor area, floor height, window-to-wall ratio and overhang depth. Then orthogonal method and the listing method are utilized to assign DesignBuilder energy simulation experiments. The purpose of minimize building energy consumption by optimizing the above listed factors is achieved. The effect of building fabric performance on result is also taken into account by setting 2 types of building fabric: conventional fabric and passive house fabric. Results show that floor height and window-to-wall ratio constitute two main related issues, followed by floor area, plane aspect ratio and orientation, and overhang depth. The optimal solution is characterized by plane aspect ratio of 2/1, orientation of south, floor area of 1 024 m², floor height of 3.6 m, window-to-wall ratio of 0.3 and overhang depth of 300 mm. The results can serve as a reference for passive design related to geometric factors in the practice of office building design in Tianjin.