Development trends on high performance microchannel heat exchangers for air conditioners

Abstract

Heat exchangers for air conditioners are generally composed of aluminum fins and copper tubes, and their performance has been improved over the years since 1970. On the other hand, microchannel heat exchangers achieve significant performance improvements by increasing refrigerant-side heat transfer performance and reducing airflow resistance through the application of microchannel tubes, and by reducing the contact thermal resistance between the fins and tubes through aluminum furnace brazing. It is also possible to reduce material costs by making it all aluminum, and in recent years, this technology has attracted attention as it can be applied to air conditioners to improve system efficiency, make products more compact, and reduce the amount of refrigerant. This paper summarizes the development trends that have been conducted to date in applying microchannel heat exchangers to air conditioners, and presents current challenges and future prospects.