Diffuse ceiling ventilation for buildings: A review of fundamental theories and research methodologies
Diffuse ceiling ventilation for buildings: A review of fundamental theories and research methodologies
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建筑物漫射天花板通风：基础理论和研究方法回顾
DOI：
10.1016/j.jclepro.2018.11.148
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发表时间：
2019
影响因子：
11.1
通讯作者：
Benner Jingru
中科院分区：
文献类型：
--
作者：
Wu Wentao;Yoon Nari;Tong Zheming;Chen Yujiao;Lv Yang;Aerenlund Torbjorn;Benner Jingru
建筑物消耗了全球40%以上的能源，通风是最大的能源消耗来源之一。可持续设计需要选择节能的通风策略。扩散吊顶通风（DCV）具有很大的节能潜力，因为通过吊顶板的压降很低（1.2 Pa）。DCV系统有三个组成部分：通风室、吊顶和通风室。空调送风至送风系统，通过多孔材料吊顶扩散至通风室内。该系统可以被设计为处理高冷却负载而不会引起热不适。本文参考了2008年至2018年发表的关于DCV的研究文章，以突出研究成果并确定研究差距。本文的一个主要目标是记录简化的理论建模方法，提出快速DCV系统设计工具。气室中的流动可以描述为多孔材料上的冲击射流。提出了一种确定喷嘴尺寸和数量的设计方法。多孔顶板中的传热被视为两相能量传输。室内热源所产生的浮力驱动了室内气流的循环，这促使人们对分层环境中热羽流的基本理论进行了深入的研究。热羽流的主要任务是计算高度和诱导体积流率，这是根据热源的类型总结的，例如，点或区域源。DCV加热效率的原理可以用湍流喷泉理论来解释。暖空气从扩散顶出来的上升高度由源弗劳德数决定。DCV系统的研究方法主要有全尺寸试验和CFD模拟。全尺寸实验通常用于基于热舒适性、室内空气品质和能源效率来评估DCV系统的性能。另一方面，CFD建模用于参数分析，以改进DCV系统的设计。最后讨论了DCV的未来研究方向。
Buildings consume more than 40% of global energy use and ventilation is one of the largest source of energy consumption. Sustainable design requires choosing energy efficient ventilation strategies. Diffuse ceiling ventilation (DCV) has a great energy saving potential due to the low pressure drop (∼2 Pa) through the ceiling panel. A DCV system has three components: plenum, suspended ceiling and ventilated room. Conditioned air is supplied to plenum, then diffuses into the ventilated room through the suspended ceiling made of porous materials. The system can be designed to handle high cooling loads without inducing thermal discomfort. This review references research articles on DCV published from 2008 to 2018 to highlight the research outcomes and to identify the research gaps. One major objective of this review paper is to document simplified theoretical modelling methods for proposing quick DCV system design tool. The flow in the plenum can be described as impingement jet over porous materials. A design procedure is proposed to determine the size and number of nozzles. The heat transfer in the porous ceiling is treated as two-phase energy transport. Buoyancy force generated by the heat sources in the room has been identified to drive the airflow circulation, which motivates the thoughtful review of fundamental theories of thermal plumes in a stratified environment. The major task on thermal plumes is to calculate the height and induced volume flow rate, which are summarized according to the type of heat sources, e.g., point or area sources. The principle behind heating efficiency of DCV might be explained by theories of turbulent fountains. The rising height of warm air coming out of diffuse ceiling is determined by the source Froude number. The popular research methods to study DCV system are full-scale experiments and CFD modelling. Full-scale experiments are often used to evaluate the performance of the DCV system based on thermal comfort, indoor air quality and energy efficiency. On the other hand, CFD modelling is used for parametric analysis to improve the design of the DCV system. Finally, future research on DCV is discussed.