(Solid + liquid) phase equilibria and heat capacity of (diphenyl ether + biphenyl) mixtures used as thermal energy storage materials
TL;DR: In this article, the authors used a differential scanning calorimetry (DSC) technique to measure heat capacities of diphenyl ether and biphenyl binary mixtures in the liquid phase up to T = 373.15 K. The well-known equations for Wilson and NRTL were used to correlate experimental solid liquid phase equilibrium data.
About: This article is published in The Journal of Chemical Thermodynamics.The article was published on 2014-07-01. It has received 33 citations till now. The article focuses on the topics: Enthalpy of fusion & UNIFAC.
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TL;DR: A collection of phase change enthalpies of organic molecules including fusion, vaporization, and sublimation enthalphies for organometallic, ionic liquids, and a few inorganic compounds can be found in this paper.
Abstract: The second part of this compendium concludes with a collection of phase change enthalpies of organic molecules inclusive of C11–C192 reported over the period 1880–2015. Also included are phase change enthalpies including fusion, vaporization, and sublimation enthalpies for organometallic, ionic liquids, and a few inorganic compounds. Paper I of this compendium, published separately, includes organic compounds from C1 to C10 and describes a group additivity method for evaluating solid, liquid, and gas phase heat capacities as well as temperature adjustments of phase changes. Paper II of this compendium also includes an updated version of a group additivity method for evaluating total phase change entropies which together with the fusion temperature can be useful in estimating total phase change enthalpies. Other uses include application in identifying potential substances that either form liquid or plastic crystals or exhibit additional phase changes such as undetected solid–solid transitions or behave ani...
107 citations
TL;DR: In this paper, isobaric specific heat capacity measurements were performed for five different nanofluid sets designed as dispersions up to 15% mass concentrations of MgO, ZnO, and ZrO 2 in pure ethylene glycol as well as ZnOs, ZOs and ZRs in an ethanol glycol+water mixture at 50:50% in volume.
101 citations
TL;DR: A review of phase equilibrium as a tool for accurately identifying suitable blended phase change materials (PCMs) to be used for thermal energy storage (TES) is presented in this paper.
Abstract: This paper presents a review of phase equilibrium as a tool for accurately identifying suitable blended phase change materials (PCMs) to be used for thermal energy storage (TES). PCM storage increases the overall energy efficiency for many applications, however, high cost and complex phase change phenomena in blends often undermine the benefits. The study of phase equilibrium as derived from phase diagrams is the key to solve these issues. It enables the evaluation of PCM-suitability through indication of temperature-composition points, e.g. congruent melting compositions, eutectics and peritectics. To clearly stake out the opportunities of a phase equilibrium-based design methodology, this paper reviews the state-of-the-art based on findings from four decades (1977–2016). On one hand, eutectics, salts-based systems, fatty acids, and alkanes dominate the existing PCM literature. Here peritectics have often been erroneously praised as suitable PCMs despite the many problems depicted from a phase equilibrium point of view. On the other hand, the most PCM-ideal congruent melting systems, as well as the blends of polyols, fats, metal alloys and organic-inorganic combinations lack full attention. This work brings forward the knowledge on these insufficiently explored yet extremely suitable phase equilibrium characteristics. In addition, comprehensive PCM-design thermal properties of these various blends are presented, as a basis to further extensive explorations, and material category-based predictions.
67 citations
TL;DR: This study presents new Nano-enhanced Phase Change Materials, NePCMs, formulated as dispersions of functionalized graphene nanoplatelets in a poly(ethylene glycol) with a mass-average molecular mass of 400 g·mol−1 for possible use in Thermal Energy Storage.
Abstract: This study presents new Nano-enhanced Phase Change Materials, NePCMs, formulated as dispersions of functionalized graphene nanoplatelets in a poly(ethylene glycol) with a mass-average molecular mass of 400 g·mol−1 for possible use in Thermal Energy Storage. Morphology, functionalization, purity, molecular mass and thermal stability of the graphene nanomaterial and/or the poly(ethylene glycol) were characterized. Design parameters of NePCMs were defined on the basis of a temporal stability study of nanoplatelet dispersions using dynamic light scattering. Influence of graphene loading on solid-liquid phase change transition temperature, latent heat of fusion, isobaric heat capacity, thermal conductivity, density, isobaric thermal expansivity, thermal diffusivity and dynamic viscosity were also investigated for designed dispersions. Graphene nanoplatelet loading leads to thermal conductivity enhancements up to 23% while the crystallization temperature reduces up to in 4 K. Finally, the heat storage capacities of base fluid and new designed NePCMs were examined by means of the thermophysical properties through Stefan and Rayleigh numbers. Functionalized graphene nanoplatelets leads to a slight increase in the Stefan number.
61 citations
TL;DR: In this article, the isobaric heat capacity of ethylene glycol (EG) based nanofluids containing three types of nitride nanoparticles: aluminium nitride, silicon nitride and titanium nitride (TiN).
61 citations
References
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Book•
01 Jan 1977
TL;DR: In this article, the authors estimate physical properties of pure components and Mixtures and show that the properties of these components and mixtures are similar to those of ideal gases and liquids.
Abstract: Chapter 1: The Estimation of Physical Properties. Chapter 2: Pure Component Constants. Chapter 3: Thermodynamic Properties of Ideal Gases. Chapter 4: Pressure-Volume-Temperature Relationships of Pure Gases and Liquids. Chapter 5: Pressure-Volume-Temperature Relationships of Mixtures. Chapter 6: Thermodynamic Properties of Pure Components and Mixtures. Chapter 7: Vapor Pressures and Enthalpies of Vaporization of Pure Fluids. Chapter 8: Fluid Phase Equilibria in Multicomponent Systems. Chapter 9: Viscosity. Chapter 10: Thermal Conductivity. Chapter 11: Diffusion Coefficients. Chapter 12: Surface Tension.
14,380 citations
TL;DR: In this paper, a new equation based on Scott's two-liquid model and on an assumption of nonrandomness similar to that used by Wilson is derived, which gives an excellent representation of many types of liquid mixtures.
Abstract: A critical discussion is given of the use of local compositions for representation of excess Gibbs energies of liquid mixtures. A new equation is derived, based on Scott's two-liquid model and on an assumption of nonrandomness similar to that used by Wilson. For the same activity coefficients at infinite dilution, the Gibbs energy of mixing is calculated with the new equation as well as the equations of van Laar, Wilson, and Heil; these four equations give similar results for mixtures of moderate nonideality but they differ appreciably for strongly nonideal systems, especially for those with limited miscibility. The new equation contains a nonrandomness parameter α12 which makes it applicable to a large variety of mixtures. By proper selection of α12, the new equation gives an excellent representation of many types of liquid mixtures while other local composition equations appear to be limited to specific types. Consideration is given to prediction of ternary vapor-liquid and ternary liquid-liquid equilibria based on binary data alone.
5,759 citations
Book•
01 Jan 1969
TL;DR: In this article, the authors introduce the notion of uniformity of intensive potentials as a criterion of phase equilibrium, and propose a model for solubilities of solids in liquid mixtures.
Abstract: 1. The Phase Equilibrium Problem. 2. Classical Thermodynamics of Phase Equilibria. 3. Thermodynamic Properties from Volumetric Data. 4. Intermolecular Forces, Corresponding States and Osmotic Systems. 5. Fugacities in Gas Mixtures. 6. Fugacities in Liquid Mixtures: Excess Functions. 7. Fugacities in Liquid Mixtures: Models and Theories of Solutions. 8. Polymers: Solutions, Blends, Membranes, and Gels. 9. Electrolyte Solutions. 10. Solubilities of Gases in Liquids. 11. Solubilities of Solids in Liquids. 12. High-Pressure Phase Equilibria. Appendix A. Uniformity of Intensive Potentials as a Criterion of Phase Equilibrium. Appendix B. A Brief Introduction to Statistical Thermodynamics. Appendix C. Virial Coefficients for Quantum Gases. Appendix D. The Gibbs-Duhem Equation. Appendix E. Liquid-Liquid Equilibria in Binary and Multicomponent Systems. Appendix F. Estimation of Activity Coefficients. Appendix G. A General Theorem for Mixtures with Associating or Solvating Molecules. Appendix H. Brief Introduction to Perturbation Theory of Dense Fluids. Appendix I. The Ion-Interaction Model of Pitzer for Multielectrolyte Solutions. Appendix J. Conversion Factors and Constants. Index.
4,550 citations
TL;DR: The International Association for the Properties of Water and Steam (IAPWS) adopted a new formulation called "The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use" as discussed by the authors.
Abstract: In 1995, the International Association for the Properties of Water and Steam (IAPWS) adopted a new formulation called “The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use”, which we abbreviate to IAPWS-95 formulation or IAPWS-95 for short. This IAPWS-95 formulation replaces the previous formulation adopted in 1984. This work provides information on the selected experimental data of the thermodynamic properties of water used to develop the new formulation, but information is also given on newer data. The article presents all details of the IAPWS-95 formulation, which is in the form of a fundamental equation explicit in the Helmholtz free energy. The function for the residual part of the Helmholtz free energy was fitted to selected data for the following properties: (a) thermal properties of the single-phase region (pρT) and of the vapor–liquid phase boundary (pσρ′ρ″T), including the phase-equilibrium condition (Maxwell criterion), and (b) t...
3,819 citations
Book•
01 Jan 1949
TL;DR: In this article, the second law of thermodynamics is used to describe the properties of pure fluids and their properties in the context of flow process analysis, and a discussion of the application of thermodynamic analysis of processes can be found.
Abstract: Preface 1 Introduction 2 The First Law and Other Basic Concepts 3 Volumetric Properties of Pure Fluids 4 Heat Effects 5 The Second Law of Thermodynamics 6 Thermodynamic Properties of Fluids 7 Applications of Thermodynamics to Flow Processes 8 Production of Power from Heat 9 Refrigeration and Liquefaction 10 Vapor/Liquid Equilbrium: Introduction 11 Solution Thermodynamics: Theory 12 Solution Thermodynamics: Applications 13 Chemical-Reaction Equilibria 14 Topics in Phase Equilibria 15 Thermodynamic Analysis of Processes 16 Introduciton to Molecular Thermodynamics Appendixes A Conversion Factors and Values of the Gas Constant B Properties of Pure Species C Heat Capacities and Property Changes of Formation D Representative Computer Programs E The Lee/Kesler Generalized-Correlation Tables F Steam Tables G Thermodynamic Diagrams H UNIFAC Method I Newton's Method Author Index Subject Index
3,684 citations