TY - JOUR
T1 - Vapor–liquid phase equilibria for the unary, binary, and ternary components of carbon dioxide (CO2), Difluoromethane (R32), and 1,1,1,2-tetrafluoroethane (R134a)
AU - Sun, Yukun
AU - Yang, Tao
AU - Zhang, Wenqiang
AU - Sun, Qiangqiang
AU - Shen, Jun
N1 - Publisher Copyright:
© 2024
PY - 2025/3
Y1 - 2025/3
N2 - The application of carbon dioxide (CO2) as a natural refrigerant is limited by its low critical temperature (313.13 K) and high critical pressure (7.3773 MPa), which pose safety challenges in thermodynamic systems. To enhance refrigeration performance, CO2 can be blended with hydrofluorocarbons (HFCs) or hydrofluoroolefins (HFOs), which exhibit more advantageous thermodynamic properties. Optimization these mixtures through careful composition adjustments can further improve efficiency. However, the thermodynamic behavior of CO2 mixtures, especially in the near critical region, remains complex and requires detailed investigation. This work focuses on the vapor–liquid equilibrium (VLE) properties of CO2, R32, and R134a across unary, binary, and ternary mixtures, respectively. The Volume–Translated Peng–Robinson (VTPR) Equation of State (EoS), incorporating binary interaction parameters (BIPs) within the van der Waals (vdW) mixing rules, is utilized to predict VLE properties. These predictions are validated against available experimental data. Additionally, Gibbs Ensemble Monte Carlo (GEMC) simulations, using all-atom force field models, are performed to compute the VLE properties of CO2 mixtures. This study also explores the microstructures of mixtures through the local mole fraction enhancement (LMFE) analysis. The findings provide a theoretical foundation for understanding CO2-based working fluids and contribute valuable insights for the design and optimization of the thermodynamic cycles.
AB - The application of carbon dioxide (CO2) as a natural refrigerant is limited by its low critical temperature (313.13 K) and high critical pressure (7.3773 MPa), which pose safety challenges in thermodynamic systems. To enhance refrigeration performance, CO2 can be blended with hydrofluorocarbons (HFCs) or hydrofluoroolefins (HFOs), which exhibit more advantageous thermodynamic properties. Optimization these mixtures through careful composition adjustments can further improve efficiency. However, the thermodynamic behavior of CO2 mixtures, especially in the near critical region, remains complex and requires detailed investigation. This work focuses on the vapor–liquid equilibrium (VLE) properties of CO2, R32, and R134a across unary, binary, and ternary mixtures, respectively. The Volume–Translated Peng–Robinson (VTPR) Equation of State (EoS), incorporating binary interaction parameters (BIPs) within the van der Waals (vdW) mixing rules, is utilized to predict VLE properties. These predictions are validated against available experimental data. Additionally, Gibbs Ensemble Monte Carlo (GEMC) simulations, using all-atom force field models, are performed to compute the VLE properties of CO2 mixtures. This study also explores the microstructures of mixtures through the local mole fraction enhancement (LMFE) analysis. The findings provide a theoretical foundation for understanding CO2-based working fluids and contribute valuable insights for the design and optimization of the thermodynamic cycles.
KW - 1,1,1,2-tetrafluoroethane
KW - Carbon dioxide
KW - Difluoromethane
KW - Monte carlo simulation
KW - Vapor–liquid equilibria
UR - http://www.scopus.com/inward/record.url?scp=85213870162&partnerID=8YFLogxK
U2 - 10.1016/j.ijrefrig.2024.12.016
DO - 10.1016/j.ijrefrig.2024.12.016
M3 - Article
AN - SCOPUS:85213870162
SN - 0140-7007
VL - 171
SP - 14
EP - 24
JO - International Journal of Refrigeration
JF - International Journal of Refrigeration
ER -