Clutch Cycling Mode of Compressor Capacity Control of Transcritical R744 Systems Compared to R134a Systems 2005-01-2033
The paper presents an experimental analysis of the performance of a prototype air conditioning system based on transcritical operation with R744 as the refrigerant. A comparative analysis of the performance of three systems is also presented: two R744 (with back pressure and manual expansion valves) and R134a with a fixed area orifice tube.
Results show that there is an optimal setting of the back pressure valve in cycling conditions that maximizes COP for the R744 system. That is very important because the system operates most of the time in cycling mode, where there is excessive capacity, and the objective is to maximize COP. Furthermore, it is shown that those values follow the same relation as developed for non-cycling operation.
Citation: McEnaney, R. and Hrnjak, P., "Clutch Cycling Mode of Compressor Capacity Control of Transcritical R744 Systems Compared to R134a Systems," SAE Technical Paper 2005-01-2033, 2005, https://doi.org/10.4271/2005-01-2033. Download Citation
Author(s):
Ryan McEnaney, Pega Hrnjak
Affiliated:
ACRC, Univ. of Illinois at Urbana-Champaign
Pages: 14
Event:
Vehicle Thermal Management Systems Conference & Exposition
ISSN:
0148-7191
e-ISSN:
2688-3627
Also in:
SAE 2005 Transactions Journal of Passenger Cars: Mechanical Systems-V114-6
Related Topics:
Air conditioning
Valves
Compressors
Pressure
Clutches
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