Sustainable cooling solutions for building environments: A comprehensive study of earth-air cooling systems

This research paper demonstrates a case study of a community-centric Earth-Air Cooling system on the Budhanilkantha. The research comprises critical attempts, encompassing heat exchanger design employing the Log Mean Temperature Difference (LMTD) technique, load estimations accomplished utilizing TRNSYS, and temperature abatement assessments executed through ANSYS simulations. The cooling system employed Geothermal energy for summer cooling. The optimization of heat exchanger dimensions required the development of pressure drop-surface area graphs utilizing spreadsheet tools. This resulted in an optimal design characterized by a tube velocity of 4.5m/s, a tube length of 46m, and a total of 12 tubes. This design led to a 33% temperature reduction, noticeably beyond the projected threshold of 23%. The Earth-Air Cooling system displayed a large heat dissipation capacity of 53.2kW, exceeding the peak cooling load requisites. This method provides a cooling mechanism for Budhanilkantha and indicates a more comprehensive application in analogous environmental contexts. To find the optimal sizing of the heat exchanger, a methodology was designed to develop an equation applicable to the domain of Nepal and all around the world that comprises similar climatic conditions.