The in-situ experiment of earth-air heat exchanger for a cafeteria building in subtropical monsoon climate
Journal
Renewable Energy
Journal Volume
157
Pages
741-753
Date Issued
2020
Author(s)
Abstract
This in-situ experimental study reports the long-term monitoring results of an earth air heat exchanger (EAHE) used to provide ventilation in a cafeteria building, in Nantou, Taiwan. The EAHE consisted of 7 parallel buried pipes with a length of 50 m and a diameter of 0.25 m. The energy performance of the system was analyzed based on data of both sensible and latent heat exchange. The monitored results have been compared with other previous cases presented in the literature to clarify the effect of various climates and design conditions on the EAHE application. The results show that despite relatively high soil temperatures underground compared with the previous case study in temperate regions, the visible temperature difference between inlet air and outlet supply air was recorded in the summer. The annual COP can reach 27.2 while the specific surface area is 0.039 m2(m3hr?1)?1, which represents a relatively low heat transfer area compared with other cases. The conclusion is that considering uncontrollable soil temperatures, the use of a relatively low specific surface area is suitable for great cooling demand in a hot and humid climate, while the design target is on maximizing the heat transfer rate rather than a higher temperature difference. ? 2020 Elsevier Ltd
Subjects
Heat transfer; Specific surface area; Temperature; Tropics; Earth-air heat exchangers; Earthair heat exchanger (EAHE); Hot and humid climate; In-situ experiments; Latent heat exchanges; Long term monitoring; Subtropical monsoon climate; Temperature differences; Heat exchangers; building; climate change; cooling; equipment; experimental study; heat transfer; in situ measurement; monsoon; performance assessment; subtropical region; temperature effect; ventilation; Nantou; Taiwan
Other Subjects
Heat transfer; Specific surface area; Temperature; Tropics; Earth-air heat exchangers; Earthair heat exchanger (EAHE); Hot and humid climate; In-situ experiments; Latent heat exchanges; Long term monitoring; Subtropical monsoon climate; Temperature differences; Heat exchangers; building; climate change; cooling; equipment; experimental study; heat transfer; in situ measurement; monsoon; performance assessment; subtropical region; temperature effect; ventilation; Nantou; Taiwan
Type
journal article