利用低品位能量总线减少玻璃围护结构夏季传热和去除室内得热的研究

With development in economy and improvement of living standards, the number and operation time of air-conditioning in summer are growing rapidly. The energy consumption of air-conditioning remains in a high level due to the growing number of glass envelope and indoor equipment. As solar radiation and most of indoor heat sources do not need to be removed by high-grade cooling source, the direct utilization of natural cooling is proposed in this study. The low-grade energy-bus technology is used to reduce the heat gain of windows and remove the indoor heat gain directly from the heat source, thereby the cooling load and operation time of air conditioning equipment in summer can be significantly reduced. The contents to be studied in this proposal includes: (1) to comprehensively analyze the building heat gain and natural cooling in summer and to propose a solution to remove the heat gain of glass envelope and indoor heat sources with low-grade cooling source like cooling water; (2) to study the effect of using low-grade cooling source to remove the heat gain of windows in summer by theoretical and experimental methods; (3) to study the effect of using low-grade cooling source to remove the indoor heat gain in theoretical and experimental methods; (4) to simulate the natural indoor temperature and cooling load of typical buildings in different climate zones with the proposed solution, and to analyze the energy saving potential of this solution in the summer in China. This study expands the scope of passive building technology, and will be of great significance for the energy saving of air-conditioning.

随着经济的发展和人民生活水平的提高，夏季空调的使用面积和时间均持续增长。大量玻璃幕墙建筑和越来越多的室内发热设备，使得空调的能耗居高不下。由于太阳辐射和室内大部分热源并不需要低温冷源才能去除，本课题提出利用自然环境的冷却能力并借助低品位能量总线的方案降低窗户的得热量并将室内产热量直接去除，从而大幅减少建筑的夏季空调负荷和空调运行时间。拟开展如下研究：（1）全面分析建筑夏季各种得热和自然界热汇的品位，提出利用冷却水等低品位冷源去除玻璃围护结构和室内得热的方案；（2）通过理论和实验研究利用低品位冷源减少墙体和窗户夏季得热量的效果；（3）通过理论和实验研究利用低品位冷源直接去除室内得热的效果；（4）模拟不同气候区典型建筑利用低品位能量总线方案降低围护结构得热和直接去除室内热量后的自然室温和夏季空调负荷，分析该方法对我国夏季空调的节能潜力。本课题拓展了被动技术建筑的范畴，对空调节能具有重要意义。

空调能耗是建筑能耗的重要组成部分。夏季透光围护结构传热与室内得热占据了空调负荷的绝大部分，通常需要机械冷源来消除这些负荷。而自然界存在大量的低品位“天然冷源”，可用于降低夏季透光围护结构传热，并去除部分室内得热，从而可显著降低机械冷源需求。为此项目分析了室内环境参数与各种边界条件的关系，提出了利用自然冷源拦截太阳辐射和传热的新型透光围护结构，建立了该新型围护结构的理论模型和热性能评价方法，提出采用自然冷源去除室内得热的方法并分析了其节能效果，并探讨了降低非均匀环境能耗的技术途径。主要成果与结论如下：1）建立了通风空调房间室内分布参数与各热边界的显式表达式，可揭示各影响因素对室内参数分布的直接影响；2）提出了利用自然冷源拦截太阳辐射和传热的“嵌管式”窗户，理论和实验结果表明，嵌管式围护结构典型工况可节能30%，并可提高室内环境的舒适性；3）嵌管式围护结构与自然冷源搭配在不同地区、不同类型建筑均有显著的节能效果，北京地区供冷季节能可达26%；4）建立了非均匀环境负荷及能耗理论，提出了采用自然冷源去除室内得热的技术方案，发现采用高效气流组织并配合不同品位能源分级处理的方案可降低空调能耗40%。