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Validation of and Optimization with a Vapor Compression Cycle Model Accounting for Refrigerant Thermodynamic and Transport Properties: With Focus on Low GWP Refrigerants for Air-Conditioning
Published
Author(s)
Harrison M. Skye, Piotr A. Domanski, Riccardo Brignoli, SANGHUN LEE, Heunghee Bae
Abstract
CYCLE_D-HX is a semi-theoretical model that simulates the performance of a vapor-compression cycle with forced-convection heat exchangers for specified temperature profiles of the heat source and heat sink. In this study, we validated CYCLE_D-HX using experimental measurements from a small (< 4 kW capacity) heat pump test apparatus operated in cooling mode. We also applied the model to simulate the performance of selected refrigerants in a system with optimized refrigerant circuitries in the evaporator and condenser. The tested refrigerants included the medium-pressure refrigerant R-134a and candidate replacements with a lower global-warming potential (GWP): R-513A, R-450A, Tern-1 (R-134a/1234yf/1234ze(E) 49.2/33.8/17.0 mass fraction, %), R-515B, and R-1234yf. We also tested high-pressure refrigerant R-410A and candidate replacements with lower-GWP: R-32, R-452B, and R-454B. The model generally agreed with experimental results, with COP and Qvol overpredicted by (0 to 3) % for the basic cycle, and by (0 to 5) % for the cycle with the liquid-line/suction-line heat exchanger (LLSL-HX). Simulations with equal compressor efficiency and optimized tube circuitry showed the COP spread among medium-pressure refrigerants could be reduced to 3 % with proper design, compared to (12 to 33) % from the experiments. The LLSL-HX improved performance of refrigerants with high molar heat capacity (here, the medium-pressure refrigerants) by (1.0 to 1.5) %. The lower-GWP medium-pressure refrigerants had COP (0.2 to 2.3) % less than R-134a. The lower-GWP high-pressure refrigerants had COP (2.3 to 3.2) % higher than R-410A.
Skye, H.
, Domanski, P.
, Brignoli, R.
, Lee, S.
and Bae, H.
(2022),
Validation of and Optimization with a Vapor Compression Cycle Model Accounting for Refrigerant Thermodynamic and Transport Properties: With Focus on Low GWP Refrigerants for Air-Conditioning, International Journal of Refrigeration, [online], https://doi.org/10.1016/j.ijrefrig.2022.11.014, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=935506
(Accessed October 8, 2025)