Evaluation of ozone-friendly hydrofluoropropane-based zeotropic refrigerant mixtures in a Lorenz-Meutzner refrigerator/freezer
- Environmental Protection Agency, Research Triangle Park, NC (United States)
- Acurex Environmental Corp., Durham, NC (United States)
The design of the Lorenz-Meutzner refrigerator/freezer has two evaporators (located in the freezer and fresh food compartments), which makes it a leading candidate for use of zeotropic refrigerant mixtures. Zeotropic mixtures can have significant temperature glides during evaporation and condensation. Performance of the zeotropic mixture can be maximized in the LM design by permitting the lower end of the temperature glide to occur in the freezer compartment evaporator and the higher end in the fresh food compartment evaporator. Several hydrofluoropropane-based zeotropes (e.g., R-227 ea/R-245ca) have been shown through steady-state modeling to outperform R-134a by up to 15%. Results from previous testing of this refrigerator/freezer using R-32/R-124 (zeotropic mixture) were published in an ASHRAE paper (Sand et al. 1993). Their results showed performance gains of approximately 3% over R-12. In the study presented in this paper, the Lorenz-Meutzner refrigerator/freezer having two evaporators and two intercoolers was experimentally tested in an environmental chamber according to Association of Home Appliance Manufacturers/Department of Energy (AHAM/DOE) testing standards using several hydrofluoropropane-based zeotropic mixtures. The results are compared to baseline testing with R-134a. The R-245ca/R-134a and R-245ca/R-152a mixtures performed comparably to R-134a. R-245ca/R-270 outperformed all zeotropic mixtures and R-134a by at least 16%. Also, a refrigerant sampling loop is added to determine the running composition of the mixture and its effects on the performance of the refrigerator/freezer.
- OSTI ID:
- 349943
- Report Number(s):
- CONF-970668-; TRN: IM9925%%94
- Resource Relation:
- Conference: American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) annual meeting, Boston, MA (United States), 28 Jun - 2 Jul 1997; Other Information: PBD: 1997; Related Information: Is Part Of ASHRAE transactions: Technical and symposium papers, 1997. Volume 103, Part 2; PB: 1072 p.
- Country of Publication:
- United States
- Language:
- English
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