Water retention and drainage on air side of heat exchangers—A review

This paper presents the recent advances in water retention and drainage performance on air side of heat exchangers under wet and dehumidifying conditions. The experimental and numerical research results are addressed. The water retention and drainage characteristics of the widely-used heat exchangers (fin-and-tube type and flat-tube type), the effects of heat exchanger surface materials, long term dry/wet cycles and liquid droplet shape on performance are highlighted. The current research results on modeling of water retention and drainage on heat exchangers are summarized.