In response to the issue of heat exchanger design in a dual evaporating temperature air conditioning system

in this study

a simulation model is established for a dual evaporating temperature air conditioning system to evaluate the impact of the heat exchanger area on the system performance. A dual evaporating temperature air-conditioning system experimental platform is built

and the compressor frequency (30–120 Hz) and supply air volumetric flow rate (400–1000 m3/h) under experimental conditions are used to obtain the cooling capacity Qc

sensible heat cooling capacity Qs

and sensible heat ratio (SHR) of the air-conditioning unit. These performance metrics are used to verify the accuracy of the established model. The range of the system operation adjustment is studied by changing the heat exchanger area (48

60

and 72 coils) in the model. The results show that with an increase in the heat exchanger area

the adjustment ranges of systems Qc

Qs

and SHR expand generally

with maximum increases of 5.0%

13.8%

and 11.8%

respectively. When the heat exchange area increased from 48 to 60 coils and 72 coils

at an air supply volumetric flow rate of 1000 m3/h and the compressor frequency of 30 Hz

the increase in Qs was 9.8% and 13.8%

respectively

indicating that when the heat exchange area increased to 60 coils

the increase in Qs was obvious. When the heat exchange area was further increased

although Qs increased

the growth rate decreased. Finally

a method was proposed to design the heat exchanger area according to the ambient temperature and humidity adjustment range

with the required cooling capacity as the target.