Comments on “Analytic Equation of State for Solid–Liquid–Vapor Phases” (Int. J. Thermophys. 24, 589 (2003))

Among the thermodynamic models applicable to solid–liquid–vapor phases, Yokozeki’s model is considered as the first repulsion-based analytic equation of state (EOS) in which a discontinuity is introduced in the isotherm. However, it was found that the model violates some physical constraints due to the empirically introduced discontinuity. This work focuses on the evaluation of the empirical basis of the model through scaled-particle theory (SPT) and a modification of the model to satisfy the physical constraint.     

On the Interpretation of Near-Critical Gas–Liquid Heat Capacities by L. V. Woodcock,Int. J. Thermophys. (2017) 38, 139: Comments

It is shown that: (1) the expressions for the isochoric (C_V) and isobaric (C_P) heat capacities of liquid and gas, coexisting in phase equilibrium, the heat capacities at saturation of liquid and gas (C_σ) and the heat capacity C_λ used in the article “On the Interpretation of Near-Critical Gas–Liquid Heat Capacities, L. V. Woodcock, Int. J. Thermophys. (2017) 38, 139” are incorrect; (2) the conclusions of the article based on the comparison of the incorrect C_V, C_P and C_λ with experimental data are also incorrect; (3) the lever rule cannot be used to define C_V and C_P in the two-phase coexistence region; (4) a correct expression for the isochoric heat capacity describes well the experimental data; (5) there is no misinterpretation of near-critical gas–liquid heat capacity measurements in the two-phase coexistence region; (6) there are no proofs in the article that: (a) the divergence of C_V is apparent; (b) it has not been established experimentally that the thermodynamic properties of fluids satisfy scaling laws with universal critical exponents asymptotically close to a single critical point of the vapor–liquid phase transition; and (c) there is no singular critical point on Gibbs density surface. We obtained the relations connecting the isochoric heat capacity in the two-phase region with thermodynamic properties at saturation of homogeneous liquid and gas which can be used to verify the equation of state.     

New Comment on Gibbs Density Surface of Fluid Argon: Revised Critical Parameters,L. V. Woodcock,Int. J. Thermophys. (2014) 35, 1770–1784

The author comments on an article by Woodcock (Int J Thermophys 35:1770–1784, 2014), who investigates the idea of a critical line instead of a single critical point using the example of argon. In the introduction, Woodcock states that “The Van der Waals critical point does not comply with the Gibbs phase rule. Its existence is based upon a hypothesis rather than a thermodynamic definition”. The present comment is a response to the statement by Woodcock. The comment mathematically demonstrates that a critical point is not only based on a hypothesis that is used to define values of two parameters of the Van der Waals equation of state. Instead, the author argues that a critical point is a direct consequence of the thermodynamic phase equilibrium conditions resulting in a single critical point. It is shown that the thermodynamic conditions result in the first and second partial derivatives of pressure with respect to volume at constant temperature at a critical point equal to zero which are usual conditions of an existence of a critical point.     

Comments on: “Starting solutions for some unsteady unidirectional flows of a second grade fluid” [Int. J. Eng. Sci. 43 (2005) 781]

A significant mathematical error is identified and corrected in a recent highly-cited paper on oscillatory flows of second-grade fluids [Fetecau & Fetecau (2005). Int. J. Eng. Sci., 43, 781–789]. The corrected solutions are shown to agree identically with numerical ones generated by a finite-difference scheme, while the original ones of Fetecau & Fetecau do not. A list of other recent papers in the literature that commit the error corrected in this Comment is compiled. Finally, a summary of related erroneous papers in this journal is presented as an Appendix.     

Comments on the article “On the propagation of harmonic plane waves under the two-temperature theory” [P. Puri,P.M. Jordan,Int. J. Eng. Sci. 44 (2006) 1113–1126]

This short note presents some comments on the article “On the propagation of harmonic plane waves under the two-temperature theory” [Puri, P., & Jordan, P. M. (2006). On the propagation of harmonic plane waves under the two-temperature theory. International Journal of Engineering Science, 44, 1113–1126]. Errors in some equations and figures in this article are pointed out and their correct forms are presented.     

Comments on “Investigation of design parameters of a domestic refrigerator by artificial neural networks and numerical simulations” by D. Kumlutas et al. [Int. J. Refrigeration 35, 1678–1689, 2012]

A paper has been published in the International Journal of Refrigeration by D. Kumlutas et al. [Int. J. Refrigeration 35, 1678–1689, 2012], which investigates design parameters of a conventional domestic refrigerator using Artificial Neural Network (ANN) simulations. The present paper attempts to discuss and comment on the above paper namely, the lack of detailed information about the design parameters of subjected refrigerator, test configuration, analysis criteria, equations and the results of solving the radiative heat transfer.     

Comments on the paper “Effect of Sr substitution on the structural properties of LaCrO3 perovskite” by R. Kumar,K. Dev Singh,and R. Kumar,and published in J. Mater. Sci.: Mater. Electron. 33, 12039 (2022)

Journal of Materials Science: Materials in Electronics - This comment argues that the paper published by R. Kumar, K. Dev Singh, and R. Kumar, entitled “Effect of Sr substitution on the...