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Clutch Cycling Mode of Compressor Capacity Control of Transcritical R744 Systems Compared to R134a Systems
Technical Paper
2005-01-2033
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
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.
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Authors
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.Also In
SAE 2005 Transactions Journal of Passenger Cars: Mechanical Systems
Number: V114-6 ; Published: 2006-02-01
Number: V114-6 ; Published: 2006-02-01
References
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