International Journal of Thermophysics最新文献

{"title":"Modeling Surface Tension of (Monoethanolamine+Water) Mixture: The Role of Equation of State, Association Scheme and Cross Association Energy","authors":"Mohammad Niksirat,&nbsp;Fatemeh Aeenjan,&nbsp;Mohammad Mahdavi Nik,&nbsp;Shahin Khosharay","doi":"10.1007/s10765-025-03613-6","DOIUrl":"10.1007/s10765-025-03613-6","url":null,"abstract":"<div><p>The gradient theory of the interface is combined with the cubic plus association and perturbed chain statistical association fluid theory equations of state to estimate the surface tension of (monoethanolamine + water) system for the first time. For each equation of state, three cases of association scheme and two forms of influence parameters have been used. Two forms of influence parameters are also applied to the gradient theory. The second form contains two exponents that lead to the accuracy of surface tension estimations, especially at low mole fractions of monoethanolamine. The highest and lowest AADs% of surface tension are 5.24 and 1.11, respectively. The interfacial density profiles show the enrichment of the surface layer with monoethanolamine. However, the enrichment of the surface layer does not exist at high concentrations of monoethanolamine in the mixture. The overall AADs% of the present model confirm its reliability for description of (monoethanolamine + water) interface.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Volumetric and Acoustic Characteristics of Potassium Sorbate with L-ascorbic Acid and Ascorbyl Glucoside: A Thermodynamic Study","authors":"Sunita Devi,&nbsp;Nabaparna Chakraborty,&nbsp;K. C. Juglan,&nbsp;Raman Kamboj","doi":"10.1007/s10765-025-03604-7","DOIUrl":"10.1007/s10765-025-03604-7","url":null,"abstract":"<div><p>The stability, safety, and shelf life of various formulations are significantly enhanced by the incorporation of antioxidants and antimicrobial preservatives. This work investigates the molecular interactions and thermodynamic characteristics of ternary mixtures consisting of <span>L</span>-ascorbic acid/Ascorbyl glucoside in aqueous solutions of Potassium sorbate, at temperatures ranging from 288.15 K to 318.15 K and concentrations from (0.0 to 0.7) mol·kg⁻¹. Experimental measurements of density and ultrasonic velocity were used to calculate key thermodynamic parameters, including partial molar volumes (<span>(V_{upphi }^{0})</span>), apparent molar volume <span>(({V}_{phi })</span>), isentropic compression <span>({(K}_{phi ,s})</span>), and their transfer parameters (<span>(V_{upphi }^{0})</span>, <span>(Delta K_{upphi }^{0})</span>). The results reveal stronger solute -solvent interactions for Ascorbyl glucoside compared to <span>L</span>-ascorbic acid. Additionally, the analysis of relative association (R_a), relaxation strength (r_s) and specific heat ratio (ϒ) provides further insights into the molecular behavior and structural dynamics of these mixtures. The co-sphere overlap theory provides a quantitative framework for interpreting molecular interactions, assessing whether ternary mixtures promote structural organization or disruption. Temperature-dependent behavior is analyzed through the first derivative (<span>(partial {text{E}}_{upphi }^{0}/partial text{T}))</span> _P, offering insights relevant to applications in the cosmetics, chemical, and pharmaceutical industries.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurements and Entropy Scaling of the Viscosity of 1-Octanol at Pressures up to 600 MPa","authors":"Dennis Alt,&nbsp;Sebastian Schmitt,&nbsp;Hans Hasse,&nbsp;Simon Stephan","doi":"10.1007/s10765-025-03612-7","DOIUrl":"10.1007/s10765-025-03612-7","url":null,"abstract":"<div><p>The viscosity of 1-octanol was determined experimentally and modeled using both empirical as well as physical models. The viscosity of liquid 1-octanol was measured using a falling-body viscometer at pressures up to 600 MPa and temperatures between 293.15 K and 373.15 K. For the physics-based modeling, entropy scaling in combination with a molecular-based equation of state, namely SAFT-VR Mie, was used. Also for the evaluation of the viscosity measurements, the SAFT-VR Mie EOS was used for describing the density of the fluid. The new viscosity data significantly extend the available literature data. For the new experimental data, the relative expanded uncertainty is below 10% for most data points. Moreover, an empirical model was developed to represent experimental data from this work. Finally, the entropy scaling model was employed and tested for describing the viscosity of 1-octanol in a wide range of states including gaseous, liquid, supercritical, and metastable states. It describes all available experimental data well and is robust when used for extrapolations.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-025-03612-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction: Experimental Analysis of Emissivity in Inconel 718 for Directed Energy Deposition Temperature Monitoring with Thermal Imaging","authors":"Jon Gabirondo-López,&nbsp;Telmo Echániz,&nbsp;Iñaki López-Ferreño,&nbsp;Jon Lambarri,&nbsp;Gabriel Alejandro López","doi":"10.1007/s10765-025-03609-2","DOIUrl":"10.1007/s10765-025-03609-2","url":null,"abstract":"","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-025-03609-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upper and Lower Limits of Thermal Diffusivity for Ti3C2Tx MXene Fiber","authors":"Shengshu Xi,&nbsp;Nan Zhang,&nbsp;Xiaona Huang,&nbsp;Dezhao Huang,&nbsp;Zhaofu Zhang,&nbsp;Yuzheng Guo,&nbsp;Yanan Yue","doi":"10.1007/s10765-025-03605-6","DOIUrl":"10.1007/s10765-025-03605-6","url":null,"abstract":"<div><p>Transition metal carbides and nitrides (MXenes), a family of two-dimensional materials, exhibit exceptional promise for energy storage applications due to their tunable structural and electrical properties. However, the pronounced adsorption properties inherent to their layered structure complicate the accurate characterization of their thermophysical properties. Here, we systematically investigate the thermal diffusivity of one-dimensional Ti₃C₂T_<i>x</i> MXene fibers using a transient electrothermal method under controlled electrical currents and vacuum environments. Our results reveal a strong correlation between the electrical and thermal responses of Ti₃C₂T_<i>x</i> MXene fibers during heating cycles. As heating progresses, the rate of voltage rise decreases, and the logarithm of the transient voltage response exhibits a robust linear dependence on time, enabling consistent extraction of thermal diffusivity. The thermal diffusivity fluctuates within experimentally determined upper and lower limits, corresponding to the degree of adsorption and desorption of water molecules, quantified at 3.6 × 10⁻⁵ m²·s⁻¹ and 1.0 × 10⁻⁶ m²·s⁻¹, respectively. By refining the understanding of MXene’s thermophysical behavior, this work provides critical insights for optimizing their energy applications and advancing materials with variable physical properties.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-025-03605-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reference Correlation of the Viscosity of Argon","authors":"Sofia G. Sotiriadou,&nbsp;Konstantinos D. Antoniadis,&nbsp;Marc J. Assael,&nbsp;Marcia L. Huber","doi":"10.1007/s10765-025-03603-8","DOIUrl":"10.1007/s10765-025-03603-8","url":null,"abstract":"<div><p>This paper presents a new wide-ranging reference correlation for the viscosity of argon, incorporating recent ab initio dilute-gas calculations and critically evaluated experimental data. The correlation is designed to be used with a high-accuracy Helmholtz equation of state that extends from the triple point (83.8058 K) to 700 K, and at pressures up to 1000 MPa. The estimated uncertainty of the correlation based on comparisons with the best experimental data indicate that the uncertainty for the gas at pressures from zero to 0.1 MPa for temperatures from 202 K to 394 K is 0.076% (at <i>k</i> = 2), the uncertainty of the best experimental data, offering a significant improvement over the current reference equation that has an uncertainty in this region of 0.5%. A zero-density correlation based on ab-initio values is incorporated that is valid over a temperature range between 84 K and 10 000 K and has an uncertainty of 0.12% (at the 95% confidence level). The estimated uncertainty for moderate pressures from 1 MPa to 100 MPa is 1% for temperatures from roughly 195 K to 300 K, rising to 2% at 175 K. For the high-pressure region, the estimated uncertainty of the correlation is about 2% for temperatures between 175 K and 308 K at pressures from 100 MPa to 606 MPa. For temperatures from 308 K to 700 K at pressures to 5.2 GPa, the equation has an estimated uncertainty of 10%. The estimated uncertainty in the liquid phase at pressures up to 34 MPa is 3%. The correlation behaves in a physically reasonable manner over the full range of applicability of the EOS, although uncertainties may be higher in regions where data were not available for full validation.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12241276/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144625235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solid-Liquid Phase Diagram of the Dimethyl + Dipropyl Adipates System: Application to Low-Temperature Thermal Energy Storage","authors":"Maria C. M. Sequeira,&nbsp;Timur Nikitin,&nbsp;Fernando J. P. Caetano,&nbsp;Hermínio P. Diogo,&nbsp;João M. N. A. Fareleira,&nbsp;Rui Fausto","doi":"10.1007/s10765-025-03598-2","DOIUrl":"10.1007/s10765-025-03598-2","url":null,"abstract":"<div><p>The present study is the continuation of our research work on di-<i>n</i>-alkyl adipates and their potential as phase change materials (PCM) for low-temperature thermal energy storage (TES). The solid–liquid phase diagram for the binary system composed of dimethyl adipate (DMA) and dipropyl adipate (DPA) is presented and analysed. In a previous study, we explored a particular binary system of <i>n</i>-alkyl adipates, namely diethyl and dibutyl adipates, and demonstrated that these compounds possess underappreciated potential as PCMs at sub-zero temperatures. The goal of the current work is to expand on this research by contributing new phase equilibrium data and deepening our understanding of the fundamental thermodynamics governing low-temperature phase behaviour in di-<i>n</i>-alkyl-adipates. The phase diagram for the DMA + DPA binary system was obtained using three complementary techniques: differential scanning calorimetry (DSC), hot-stage microscopy (HSM), and Raman spectroscopy. DSC analysis of sixteen compositions, including the two pure compounds, provided both the temperature and enthalpy values for the solid–liquid and solid–solid phase transitions. The binary system displays eutectic behaviour at low temperatures, with the eutectic point found at 252.83 K and a composition of approximately x_DPA = 0.77. Raman spectroscopy confirmed that the system is characterized by a non-isomorphic eutectic phase diagram, indicating differences in the crystal structures of the solid phases. The <i>liquidus</i> line of the binary phase diagram was successfully described using a suitable fitting equation, yielding a root mean square deviation of 0.65 K, indicating excellent agreement between the experimental data and the theoretical model. This fitting also allowed an accurate prediction of the eutectic composition and temperature. A Tammann diagram is also presented, further confirming the eutectic composition and associated enthalpy. This work addresses a gap in the literature by presenting, for the first time, the solid–liquid phase equilibrium behaviour of the DMA + DPA binary system (including the detailed solid–liquid phase diagram of the system). The findings provide valuable insight into the potential use of this system as PCM for sub-zero TES applications, supporting their consideration in future thermal energy storage technologies.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12241232/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144625236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective Thermal Conductivity of 1-Pentanol-Based Nanofluids Containing Oblate Silicon Dioxide Nanoparticles","authors":"Francisco E. Berger Bioucas,&nbsp;Cornelia Damm,&nbsp;Thomas M. Koller,&nbsp;Andreas P. Fröba","doi":"10.1007/s10765-025-03597-3","DOIUrl":"10.1007/s10765-025-03597-3","url":null,"abstract":"<div><p>This work investigates the effect of the shape of oblate particles on the effective thermal conductivity <i>λ</i>_eff of nanofluids. Spherical silicon dioxide (SiO₂) nanoparticles with a mean diameter of 176 nm were plastically deformed in a stirred media mill to obtain non-spherical oblate particles of nearly cylindrical shape without significantly changing the volume of the individual particles. This allowed to study 1-pentanol-based nanofluids with varying particle sphericity <i>ψ</i> of 1.00, 0.50, or 0.45 at particle volume fractions <i>φ</i>_p up to 0.16, which exceeds the value range by a factor of two compared to previous studies on nanofluids with non-spherical particles. Measurements of <i>λ</i>_eff and of the thermal conductivity of the base fluid 1-pentanol, <i>λ</i>_bf, were performed at temperatures <i>T</i> from (298.15 to 358.15) K at ambient pressure using a steady-state guarded parallel-plate instrument (GPPI) with an expanded (coverage factor <i>k</i> = 2) uncertainty between (2.0 and 2.2) %. The experimental results indicate that the varying shape of the particles with about ten times higher thermal conductivity than <i>λ</i>_bf does not have a significant effect on <i>λ</i>_eff within the experimental uncertainties over the investigated ranges of <i>φ</i>_p and <i>T</i>. This behavior is not reflected by the semi-empirical Hamilton-Crosser (HC) model that predicts an increase in the thermal conductivity ratio <i>λ</i>_eff·<i>λ</i>_bf⁻¹ with decreasing <i>ψ</i>. A better representation is given by the correct formulation of the effective medium theory <i>via</i> the model of Nan <i>et al.</i>, which can be applied to dispersions with completely misoriented ellipsoidal particles. This is apparently related to the counterbalance of the enhancing effect of non-spherical particles on <i>λ</i>_eff due to their orientation-averaged extended heat conduction paths along the heat flux compared to spherical particles and the reducing effect caused by a Kapitza resistance at the particle/liquid interface, which increases with decreasing <i>ψ</i> for a given <i>φ</i>_p.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-025-03597-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Green Nanoparticles on the Thermal Performance of A Shell and Helically Coiled Tube Heat Exchanger – A Numerical Study","authors":"D. Saravanan,&nbsp;K. Sureshkumar","doi":"10.1007/s10765-025-03593-7","DOIUrl":"10.1007/s10765-025-03593-7","url":null,"abstract":"<div><p>Growing awareness of the harmful environmental impacts of fossil fuel-based systems, combined with technological advancements and increasing energy demand, has highlighted the need for more efficient energy systems. This has resulted in a greater use of shell and helically coiled tube heat exchanger (SHCTHE) owing to its superior performance. This study focuses on enhancing the thermal efficiency of SHCTHE by improving the heat transfer coefficient using green-synthesized silver (Ag) nanoparticles derived from Azadirachta indica and Melia composita Willd with varying concentrations (0.02%, 0.04%, and 0.06%) dispersed in deionized water. Both computational and experimental approaches were used to evaluate the impact of nanofluids on the efficiency of the SHCTHE. Simulations were performed with ANSYS Fluent under consistent conditions, varying the flow rates. The findings revealed that nanofluids synthesized from Melia composita exhibited a 21% intensification in the mean heat transfer rate and a 15% augmentation in the heat transfer coefficient compared to those derived from Azadirachta indica. Building on promising simulation results, the Ag-DI nanofluids were tested in a heat exchanger under laboratory conditions, where the experimental outcomes closely matched the simulations, revealing only minor discrepancies. The average discrepancy between the simulated and experimental heat transfer rate observed for Azadirachta indica and Melia composita Willd was 3.54% and 2%, correspondingly, at a cold FR of 1.5 l/min. MC exhibited an elevated heat transfer coefficient spanning from 2238.611 to 3805.155 W/m²K, making it a promising green nanofluid for SHCTHE with substantial thermal performance enhancement.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145162004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Optimization of Molten Salt Melting Process in Direct Absorption Solar Collectors by Filling Dynamic Sinkable Copper Foam Plate","authors":"Zhu Zhiwei,&nbsp;Zhou Ruirui,&nbsp;Liu Yi,&nbsp;Li Ling","doi":"10.1007/s10765-025-03592-8","DOIUrl":"10.1007/s10765-025-03592-8","url":null,"abstract":"<div><p>A dynamic sinkable copper foam plate (DSCFP) was developed to enhance the melting efficiency of molten salt in direct absorption solar collectors (DASC). The proposed approach develops a simple and reliable method to simultaneously balance light penetration and photothermal conversion efficiency in molten salts. Compared with molten salt without copper foam, the DSCFP significantly improves the absorption of incident solar radiation. In comparison to a fully filled copper foam structure, the DSCFP increased the <i>Nu</i> by 5.27 times, resulting in a 12.1 % reduction in melting time and a 23.2 % improvement in thermal efficiency. Moreover, the thickness and pore density of the copper foam were found to have a significant impact on the thermal performance of the DASC. Reducing the foam thickness from 4 to 2 cm led to a 134.4 % decrease in melting time and a 1.8 % increase in thermal efficiency. Similarly, decreasing the pore density of the copper foam from 20 to 10 ppi resulted in a 26.5 % increase in melting time and a 2.5 % decrease in thermal efficiency.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145162005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}