Abstract Diffuse ceiling ventilation system is an air distribution system based on the low-impulse supply of air through the perforated panels installed as the suspended ceiling. A ceiling with diffuse supply typically consists of active and passive panels, where active panels allow airflow. Diffuse ceiling ventilation system has been proven to have a higher cooling capacity compared to conventional air distribution systems, e.g. mixing or displacement ventilation systems. Several parameters have an impact on the cooling capacity of the system though. The present research study evaluates the cooling capacity of the diffuse ceiling ventilation system in connection to two essential parameters, i.e. the distribution of heat load in the room and the distribution of active diffuse panels in the ceiling. The evaluation is based on full-scale experiments performed in a laboratory-controlled environment as well as numerical studies with Computational Fluid Dynamics (CFD) simulations. The cooling capacity of the system in several scenarios with different heat load and active diffuse panel distribution are compared under a certain thermal comfort condition. The results indicate the highest cooling capacity in the scenario with evenly distributed heat load in the room and compact distribution of active diffuse panels in the ceiling, while the active panels cover almost one-third of the suspended ceiling. The system is at its minimum cooling capacity in the scenario with compact heat load distribution in the room and disperse distribution of active diffuse panels in the ceiling.

中文翻译：

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漫射天花板通风系统的冷却能力以及热负荷和漫射板分布的影响

摘要 漫射天花板通风系统是一种空气分配系统，其基础是通过安装为吊顶的穿孔板进行低脉冲空气供应。带有扩散供应的天花板通常由主动和被动面板组成，其中主动面板允许气流。与传统的空气分配系统（例如混合或置换通风系统）相比，散流天花板通风系统已被证明具有更高的冷却能力。但是，有几个参数会影响系统的冷却能力。本研究根据两个基本参数来评估漫射天花板通风系统的冷却能力，即房间内的热负荷分布和天花板中活动漫射板的分布。该评估基于在实验室控制环境中进行的全尺寸实验以及使用计算流体动力学 (CFD) 模拟进行的数值研究。比较了系统在一定热舒适条件下不同热负荷和主动扩散板分布的几种场景下的制冷能力。结果表明，在房间内热负荷分布均匀且天花板中活动扩散板分布紧凑的情况下，制冷能力最高，而活动板几乎覆盖了吊顶的三分之一。在房间内热负荷分布紧凑、天花板上有源扩散板分散分布的情况下，系统处于其最小冷却能力。