Decentralised, wall mounted ventilation is one of alternative to typical – cross flow or “heat wheel” recovery air handling units (AHU) system when it is not possible to install it. It solves problems such as the need for more space, power consumption of fans, and investment costs. This experimental study aims to analyse the performance of the unique constructed decentralised air handling unit (DAHU) prototype that has a special balls-packed regenerative heat exchanger. The development of the DAHU also aimed to simplify the operation and production of the unit to make it more affordable and easier to manufacture. As the DAHU is constructed from individually sized components, the pressure losses of the diffuser, the regenerator, the screens to hold the balls, the filter and the fan were measured and the actual DAHU airflow was determined. The general operation of the DAHU was tested in a climatic chamber to determine the appropriate cycle times for this type of device, as well as the heat recovery efficiency at different outdoor air temperatures. Five different DAHU operating cycles were analysed. It was found that the duration of supply air must be longer than the duration of extract air to achieve higher efficiency. Therefore, DAHU's subsequent heat exchanger studies were performed for four airflows. The highest DAHU heat recovery efficiency was achieved (above 70 %) with a supply and extract duration of 150 s. It has been found that the efficiency of this DAHU increases with decreasing outdoor air temperature because of the storage properties of the balls. The analysis showed that this type of DAHU could be suitable for use in cooler and colder climates.

中文翻译：

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带球形蓄热室的分散式空气处理机组原型的实验分析


当无法安装时，分散式壁挂式通风是典型的横流或 “热轮 ”回收空气处理装置 （AHU） 系统的替代方案之一。它解决了需要更多空间、风扇功耗和投资成本等问题。本实验研究旨在分析独特构造的分散式空气处理装置 （DAHU） 原型的性能，该原型具有特殊的球形填充再生热交换器。DAHU 的开发还旨在简化该装置的操作和生产，使其更实惠、更容易制造。由于 DAHU 由单独尺寸的组件构成，因此测量了扩散器、再生器、固定球的滤网、过滤器和风扇的压力损失，并确定了实际的 DAHU 气流。在气候室中对 DAHU 的一般运行进行了测试，以确定此类设备的适当循环时间，以及不同室外空气温度下的热回收效率。分析了 5 种不同的 DAHU 操作周期。研究发现，送风的持续时间必须长于抽气的持续时间才能实现更高的效率。因此，DAHU 随后对四种气流进行了换热器研究。在供应和提取持续时间为 150 s 时，实现了最高的 DAHU 热回收效率 （高于 70 %）。已经发现，由于球的存储特性，这种 DAHU 的效率随着室外空气温度的降低而增加。分析表明，这种类型的 DAHU 可能适合在较凉爽和较冷的气候中使用。