Thermodynamic Properties of Monatomic, Diatomic, and Polyatomic Gaseous Natural Refrigerants: A Molecular Dynamics Simulation

Document Type : Full Lenght Research Article


Faculty of Engineering and Technology, Department of Mechanical Engineering , Imam Khomeini International University


Owing to their lower adverse environmental impacts, natural refrigerants have recently attracted a huge deal of attention. In this regard, the present study is aimed to evaluate the thermodynamic properties of different gaseous natural refrigerants at the molecular level using molecular dynamics (MD) simulations. In this context, the density (as a representative of structural features), enthalpy, and specific heat capacity (as representatives of energy properties) of several natural gaseous refrigerants including helium, nitrogen, methane, and ethane were assessed. Lennard-Jones potential was used for simulation of helium and nitrogen while AIREBO potential and OPLS-AA force-fields were employed for simulation of methane and ethane as polyatomic hydrocarbon refrigerants. Simulations are carried out at various temperatures above the boiling point and pressures of 1, 2, and 5 bar. MD results were in good agreement with the experimental data. Among the applied potentials, AIREBO potential offered results closer to the experimental data as compared with OPLS-AA force-field. The methane-ethane mixture was also addressed at different pressures and compared with the Peng-Robinson equation of state. The results of this study indicated that molecular dynamics can be employed as a reliable tool for predicting the thermodynamic properties of natural refrigerants. The results can be used in the refrigeration cycles.


Main Subjects

[1] S. Barrault, M. Nemer, La F-GasII et son impact sur les émissions de fluides frigorigènes en France à l’Horizon 2035, Refrig. Sci. Technol. (2015) 2412–2419.
[2] B.I. Lee, M.G. Kesler, A generalized thermodynamic correlation based on three‐parameter corresponding states, AIChE J. 21 (1975) 510–527.
[3] D.Y. Peng, D.B. Robinson, A New Two-Constant Equation of State, Ind. Eng. Chem. Fundam. 15 (1976) 59–64.
[4] H. Atalay, M.T. Coban, Modeling of Thermodynamic Properties for Pure Refrigerants and Refrigerant Mixtures by Using the Helmholtz Equation of State and Cubic Spline Curve Fitting Method, Univers. J. Mech. Eng. 3 (2015) 229–251.
[5] M.O. McLinden, E.W. Lemmon, R.T. Jacobsen, Thermodynamic properties for the alternative refrigerants, Int. J. Refrig. 21 (1998) 322–338.
[6] C. Coquelet, J. El Abbadi, C. Houriez, Prévision des propriétés thermodynamiques des fluides frigorigènes avec une nouvelle équation cubique d’état à trois paramètres, Int. J. Refrig. 69 (2016) 418–436.
[7] P. Stra̧k, S. Krukowski, Molecular nitrogen- N2 properties: The intermolecular potential and the equation of state, J. Chem. Phys. 126 (2007).
[8] C.G. Aimoli, E.J. Maginn, C.R.A. Abreu, Transport properties of carbon dioxide and methane from molecular dynamics simulations, J. Chem. Phys. 141 (2014).
[9] U.K. Deiters, R.J. Sadus, Ab Initio Interatomic Potentials and the Classical Molecular Simulation Prediction of the Thermophysical Properties of Helium, J. Phys. Chem. B. 124 (2020) 2268–2276.
[10] M.R. Shirts, J.D. Chodera, Statistically optimal analysis of samples from multiple equilibrium states, J. Chem. Phys. 129 (2008).
[11] E.K. Goharshadi, M. Abbaspour, Determination of potential energy function of methane via the inversion of reduced viscosity collision integrals at zero pressure, Fluid Phase Equilib. 212 (2003) 53–65.
[12] M. Abbaspour, Computation of some thermodynamics, transport, structural properties, and new equation of state for fluid methane using two-body and three-body intermolecular potentials from molecular dynamics simulation, J. Mol. Liq. 161 (2011) 30–35.
[13] S. MURAD, K.E. GUBBINS, Molecular Dynamics Simulation of Methane Using a Singularity-Free Algorithm, in: 1978: pp. 62–71.
[14] M. Schoen, C. Hoheisel, O. Beyer, Liquid CH4, liquid CF4 and the partially miscible liquid mixture CH4/CF4: A molecular dynamics study based on both a spherically symmetric and a four-centre lennard-jones potential model, Mol. Phys. 58 (1986) 699–709.
[15] H. Stassen, On the pair potential in dense fluid methane, J. Mol. Struct. THEOCHEM. 464 (1999) 107–119.
[16] R.L. Rowley, T. Pakkanen, Determination of a methane intermolecular potential model for use in molecular simulations from ab initio calculations, J. Chem. Phys. 110 (1999) 3368–3377.
[17] E.A. Mason, W.E. Rice, The intermolecular potentials of helium and hydrogen, J. Chem. Phys. 22 (1954) 522–535.
[18] N. Tchouar, M. Benyettou, F.O. Kadour, Thermodynamic, Structural and Transport Properties of Lennard-Jones Liquid Systems. A Molecular Dynamics Simulations of Liquid Helium, Neon, Methane and Nitrogen, Int. J. Mol. Sci. 4 (2003) 595–606.
[19] T. Kristóf, G. Rutkai, L. Merényi, J. Liszi, Molecular simulation of the Joule-Thomson inversion curve of hydrogen sulphide, Mol. Phys. 103 (2005) 537–545.
[20] C.G. Aimoli, E.J. Maginn, C.R.A. Abreu, Force field comparison and thermodynamic
M. Abbasi / JHMTR 8 (2021) 61- 69 69
property calculation of supercritical CO2 and CH4 using molecular dynamics simulations, Fluid Phase Equilib. 368 (2014) 80–90.
[21] M. Mafi, M. Amidpour, S.M.M. Naeynian, Comparison of low temperature mixed refrigerant cycles for separation systems, Int. J. Energy Res. 33 (2009) 358–377.
[22] M.S. Alam, J.H. Jeong, Molecular dynamics simulations on homogeneous condensation of R600a refrigerant, J. Mol. Liq. 261 (2018) 492–502.
[23] X. Wu, Z. Yang, Y. Duan, Evaporation of R32/R1234yf mixture nanodroplets on a smooth substrate: Molecular dynamics simulation, Chem. Phys. Lett. 733 (2019) 136672.
[24] G.A. Kaminski, R.A. Friesner, J. Tirado-Rives, W.L. Jorgensen, Evaluation and reparametrization of the OPLS-AA force field for proteins via comparison with accurate quantum chemical calculations on peptides, J. Phys. Chem. B. 105 (2001) 6474–6487.
[25] S.J. Stuart, A.B. Tutein, J.A. Harrison, A reactive potential for hydrocarbons with intermolecular interactions, J. Chem. Phys. 112 (2000) 6472–6486.
[26] S. Plimpton, Fast Parallel Algorithms for Short-Range Molecular Dynamics, J. Comput. Phys. 117 (1995) 1–19.
[27] L. Verlet, Computer “experiments” on classical fluids. I. Thermodynamical properties of Lennard-Jones molecules, Phys. Rev. 159 (1967) 98–103.
[28] A.I. Jewett, Z. Zhuang, J.-E. Shea, Moltemplate a Coarse-Grained Model Assembly Tool, 2013.
[29] On the determination of molecular fields. —II. From the equation of state of a gas, Proc. R. Soc. London. Ser. A, Contain. Pap. a Math. Phys. Character. 106 (1924) 463–477.
[30] R.K. Pathria, P.D. Beale, Statistical Mechanics, 2011.
[31] P.J. Linstrom, W.G. Mallard, The NIST Chemistry WebBook: A chemical data resource on the Internet, J. Chem. Eng. Data. 46 (2001) 1059–1063.
Volume 8, Issue 1
Winter and Spring 2021
Pages 61-69
  • Receive Date: 11 September 2020
  • Revise Date: 07 December 2020
  • Accept Date: 09 December 2020