While heat pump technology is recognized for its energy efficiency, traditional heat pump air conditioners often rely on fluorocarbon refrigerants, which contribute to global warming. Therefore, there is a pressing need to reduce refrigerant charge and enhance heat exchanger performance. The authors have developed a Vertical Flat Tube heat exchanger (VFT) that utilizes small-diameter flat tubes arranged vertically in a compact configuration. The VFT achieves a 40% improvement in heat exchanger performance and a 20% reduction in the volume of the heat exchanger.
Kishida et al. (Wed,) studied this question.