The flow path numbers of an outdoor heat exchangerare always constant from the inlet to the outlet and cannot vary with the different refrigerant properties between the inlet and the outlet

which results in bad heat transfer. This study proposes a distributed flow path for an outdoor heat exchanger to improve the annual performance factor (APF) of air conditioners. The distributed flow path

with an increased path number from the low-quality zone to the high-quality zone

is configured according to the refrigerant property of the entire outdoor unit. Both the heat transfer and the pressure drop of the outdoor heat exchanger with the distributed flow path were analyzed by heat exchanger simulation software. Finally

the advantages of the distributed flow path on the heat transfer capacity were experimentally validated. The results showed that

compared with air-conditioning outdoor heat exchangers with fixed flow paths

the APF of the air conditioner systems with distributed flow paths increased by 1.8% to 5.8%;the rated heating capacity

low-temperature heating capacity

and ultra-low-temperature heating capacity of outdoor heat exchangers also increased by approximately 4.3%

7.5%

and 5.9%

respectively.