ANALYSIS OF THE EFFECTIVENESS COEFFICIEN OF DECENTRALIZED VENTILATION SYSTEMS WITH HEAT RECOVERY

This article is devoted to studying of decentralized supply-exhaust ventilation systems (DSEVS) with heat recovery, which are an important element for ensuring energy-efficient air exchange in modern hermetic buildings. The problems of natural ventilation, which in modern conditions cannot provide an adequate level of air exchange without heat loss, especially in winter and summer, have been studied, and the effectiveness of mechanical ventilation systems has been substantiated. A comparison of centralized and decentralized systems is made, highlighting the advantages of decentralized systems in terms of ease of installation, space saving and the possibility of installation in already renovated premises. In the work, three samples of DSEVS equipped with copper heat exchangers, which provide high heat transfer, were analysed. The main goal of the study was to identify the strengths and weaknesses of the existing devices and develop recommendations for their improvement, taking into account the climatic features of the regions of Ukraine and Europe. On the basis of the conducted research, the results of the efficiency of each of the systems, which are sufficiently close to each other, were obtained. This, accordingly, was expected, since the heat exchangers of these systems are made of the same material – copper. During the tests, the need for better tightness of each of the systems was determined, which can improve the results of their efficiency in the future. At the same time, the results of these studies may vary depending on the determination of the real air consumption of each of the devices, as well as the mass balance of the supply and exhaust air flows, which may differ. The study confirms the effectiveness of countercurrent systems working on simultaneous inflow and extraction as optimal solutions for maintaining a comfortable and energy-efficient microclimate. The obtained results can be directed to the optimization of the design of the DSEVS and the possibility of operation of such systems in combination with natural or other mechanical ventilation systems.