长江下游地区居住建筑保温方式适用性研究

With the rapid development of economics and urbanization in the lower reaches of the Yangtze river (i.e., the LRYR) zone of China, the population has been increased greatly in the past few decades, and this result in high building densities in most of the cities or urban agglomerations in this region. In current days, space heating in winter seasons is becoming more and more popular in residential buildings due to the improvement of people's living standard. Thermal insulation panels and other materials have been used in many buildings for reducing heating consumption in this zone. However, few strategies are available for building envelop insulation in the LRYR region. As an expedient way, the techniques used for building thermal insulation in the cold climate zones of China are employed in the LRYR region, i.e., the materials with high initial cost and fire hazard are usually used for the envelop insulation.This means that there exists some blindness and wrong way for the selection of the thermal insulation strategy. The main aim of the present study is propose to find some available ways to make full use of the potential of the thermal insulation materials/techniques according to the integrated investigations in the LRYR region, and the primary study are as follows: (1) Considering the features of short time heating in residential buildings in the LRYR region, the effects of both the interior and exterior thermal insulations on energy efficiencies of short time and local space heating will be explored by employing field test and numerical simulations. (2) To estimate and calculate the influences of the insulation layer locations on the absorption of solar radiation by the layer and its heat emission efficiency at night in summer. (3) Based on the results mentioned above, the annual energy consumptions of heating and cooling of the buildings will be analyzed and predicting models for energy efficiency estimation of the insulation mode will be provided, and some recommendations for building thermal insulation in the LRYR region will be suggested according to the climatic characteristics of this zone.

我国长江下游地区人口集中，建筑稠密。随着这一地区居民经济水平的提高和城市化速度的加快，冬季建筑供暖行为越来越普遍。为降低供暖能耗，加强了建筑保温措施。由于长江下游地区围护结构保温方式适宜性的研究几乎为空白，因此，在长江下游地区的城市群中，大量居住建筑照搬北方地区建筑节能的经验，采用经济成本高且消防隐患大的外保温方式。在保温方式的选择上存在着很大的盲目性。 本项目拟通过开展对以下内容的研究, 为建筑保温在长江下游地区最大限度地发挥其节能功效提供理论依据和数据支撑：（1）针对局部时段供暖的特征，利用数值模拟和实测方法，探究外保温和内保温墙体对短时间供暖用能利用率的影响。（2）计算分析保温层位置对太阳辐射实际吸收率和对夏季夜间散热效果的影响；（3） 基于上述研究结果，对全年供暖供冷能耗进行分析，给出不同保温方式节能效果的预测模型，寻求该地区冬夏季气候特征都可接受的建筑保温方式。

我国长江下游地区人口集中，聚居区建筑稠密。随着这一地区居民经济水平的提高和城市化速度的加快，冬季建筑供暖已成为越来越普遍的现象。为降低供暖能耗，加强了建筑保温措施。因这一地区冬季供暖具有“局部空间，局部时间”的特点，墙体传热呈现明显的动态特征，故与北方集中供暖建筑的近似稳态传热过程差异很大。由于尚缺乏长江下游地区围护结构保温方式适宜性的研究，因此，在这一地区的城市群中，大量居住建筑往往套用北方地区建筑节能的经验，采用经济成本高且消防隐患大的外保温方式，因此，在保温方式的选择上存在着很大的盲目性。为使建筑保温成本在长江下游地区最大限度地发挥其节能功效，并为此提供基本理论依据和数据支撑，本项目开展了以下研究：（1）针对该地区局部时段局部空间供暖的特征，利用实测和数值模拟方法，研究了外保温和内保温墙体对短时间供暖用能利用率的影响。结合不同室外气候和供暖行为特征，深入分析了间断供暖房间能耗组成，发现随着外墙保温层厚度增加，邻室传热损失和停止供暖期间室内蓄热体冷却成为下一次开始供暖的主要负荷来源，这部分能耗无法通过加强外围护结构保温性能来减小或消除。（2）分析了保温层位置对太阳辐射实际吸收率和对夏季夜间散热效果的影响，发现虽然内保温对太阳能的实际吸收率大于外保温，但由于其热桥效应较大。因此，选择适合的保温层位置时，应考虑建筑内居民的供暖行为特征。结合长江下游地区各典型城市的当地风频分布、太阳辐射强度，研究了城市冬季主导风向对太阳能实际吸收率和保温构造方案选择的综合影响效果，扩展了影响间断供暖建筑能耗和最佳热阻选取的影响因素群；（3）基于上述研究结果，对全年供暖供冷能耗进行了详细分析，给出了不同保温方式节能效果的预测模型。此外，针对长江下游地区居民对通风的偏好，将冬季停止供暖期间的通风行为、供暖间断时间和内墙构造特征纳入其中。