International Journal of Thermophysics最新文献_第3页

Thermophysical Properties of NbAlO4 and TaAlO4

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-02-08 DOI: 10.1007/s10765-025-03512-w

Julian Gebauer, Magnus Rohde, Peter Franke, Hans Jürgen Seifert

{"title":"Thermophysical Properties of NbAlO4 and TaAlO4","authors":"Julian Gebauer, Magnus Rohde, Peter Franke, Hans Jürgen Seifert","doi":"10.1007/s10765-025-03512-w","DOIUrl":"10.1007/s10765-025-03512-w","url":null,"abstract":"<div>Thermophysical properties of the ternary oxides NbAlO4 and TaAlO4 are experimentally determined. For NbAlO4, the molar heat capacity is 98.9 J (mol(cdot)K)−1 at 0 (^{circ })C up to 155.6 J (mol(cdot)K)−1 at 950 (^{circ })C and for TaAlO4 97.1 J (mol(cdot)K)−1 at 0 (^{circ })C up to 154.2 J (mol(cdot)K)−1 at 950 (^{circ })C, respectively. Maier-Kelley polynomials are provided for the molar heat capacities. Thermal diffusivities in the range from 20 (^{circ })C to 700 (^{circ })C ((alpha _{NbAlO_{4}}): from 0.009 to 0.004 cm2·s−1 and (alpha _{TaAlO_{4}}): from 0.017 to 0.005 cm2·s−1), bulk densities at 25 (^{circ })C ((rho _{NbAlO_{4}})= 3.94 g(cdot)cm−3 and (rho _{TaAlO_{4}})= 6.07 g·cm−3) and melting points of the oxides are measured, and the thermal conductivities are calculated from these properties. The thermal conductivity from 20 (^{circ })C to 700 (^{circ })C of NbAlO4 (lambda _{ NbAlO_{4}}) is in the range from 0.020 to 0.013 W·cm−1·K−1 and of TaAlO4 (lambda _{TaAlO_{4}}) in the range from 0.039 to 0.015 W·cm−1·K−1, respectively. A porosity correction for thermal conductivities is applied, and with that, data for perfectly dense material are provided.</div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 3","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-025-03512-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361838","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}

引用次数: 0

Euler–Euler Numerical Model for Transport Phenomena Modeling in a Natural Circulation Loop Operated by Nanofluids

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-02-08 DOI: 10.1007/s10765-024-03497-y

Blaž Kamenik, Nejc Vovk, Elif Begum Elcioglu, Firat Sezgin, Erdem Ozyurt, Ziya Haktan Karadeniz, Alpaslan Turgut, Jure Ravnik

{"title":"Euler–Euler Numerical Model for Transport Phenomena Modeling in a Natural Circulation Loop Operated by Nanofluids","authors":"Blaž Kamenik, Nejc Vovk, Elif Begum Elcioglu, Firat Sezgin, Erdem Ozyurt, Ziya Haktan Karadeniz, Alpaslan Turgut, Jure Ravnik","doi":"10.1007/s10765-024-03497-y","DOIUrl":"10.1007/s10765-024-03497-y","url":null,"abstract":"<div>This paper explores a computational approach to model multiphase heat transfer and fluid flow in a natural circulation loop utilizing nanofluids. We propose and implement an Euler–Euler framework in a CFD environment, incorporating an innovative boundary condition to preserve mass conservation during thermophoretic particle flux. The model’s accuracy is verified through a one-dimensional example, by comparing results against both an Euler–Lagrange model and an in-house finite volume solution. Experimental validation is conducted with aluminum oxide nanofluids at varying nanoparticle concentrations. We prepared the nanofluids and measured their thermophysical properties up to (60^circ)C. We assess the thermal performance of the nanofluid in natural circulation loop at different heating powers via experiment and numerical simulations. The findings reveal that the heat transfer enhancement offered by the nanofluid is modest, with minimal differences observed between the proposed Euler–Euler approach and a simpler single-phase model. The results underscore that while the Euler–Euler model offers detailed particle–fluid interactions, its practical thermal advantage is limited in this context.</div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 3","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-024-03497-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361839","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}

引用次数: 0

Device for Direct Barocaloric Measurement

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-02-03 DOI: 10.1007/s10765-025-03511-x

Marcelo Augusto Yanes Moia, Flavio Clareth Colman, Gustavo Hannoun Giudai, William Imamura, Erik Oda Usuda, Gabriel Fornazaro, Laís Weber Aguiar, Wagner André dos Santos Conceição, Monica Ronobo Coutinho, Silvia Luciana Favaro, Cleber Santiago Alves, Alexandre Magnus Gomes Carvalho, Paulo Vinicius Trevizoli, Jader Riso Barbosa Junior, Rita de Cássia Colman Simões, Eduardo Radovanovic, Jean Rodrigo Bocca

{"title":"Device for Direct Barocaloric Measurement","authors":"Marcelo Augusto Yanes Moia, Flavio Clareth Colman, Gustavo Hannoun Giudai, William Imamura, Erik Oda Usuda, Gabriel Fornazaro, Laís Weber Aguiar, Wagner André dos Santos Conceição, Monica Ronobo Coutinho, Silvia Luciana Favaro, Cleber Santiago Alves, Alexandre Magnus Gomes Carvalho, Paulo Vinicius Trevizoli, Jader Riso Barbosa Junior, Rita de Cássia Colman Simões, Eduardo Radovanovic, Jean Rodrigo Bocca","doi":"10.1007/s10765-025-03511-x","DOIUrl":"10.1007/s10765-025-03511-x","url":null,"abstract":"<div>Direct measurements of adiabatic temperature change ((Delta {{varvec{T}}}_{{varvec{S}}})) to characterize the barocaloric effect (σb-CE) were a challenge and a point of interest for many research groups. In this work, we propose a device to measure (Delta {{varvec{T}}}_{{varvec{S}}}) in a system with a simplified design and a new method to seal the pressure chamber. This new concept was tested for several materials in solid or liquid states. The methodology involves acquiring a temperature curve as a function of time under desired initial conditions. The results showed that the equipment can measure solid-state materials in powder, flakes, or solid bodies, in the absence or presence of a phase transition. When using coconut oil at high temperatures, for example, the apparatus remained sealed until the end of the experimental run. Promising values of σb-CE, ranging from large to colossal, were captured for polymers, composites, first-order-transition materials, coconut oil, paraffin. This concept can inspire new research groups to develop equipment to study the barocaloric effect.</div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 3","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143107913","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}

引用次数: 0

Experimental Compressed Liquid Density Measurements and Correlation of the Binary Mixture {n-Pentane (R601) + Trans-1-chloro-3,3,3-trifluoro-1-propene (R1233zd(E))}

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-02-03 DOI: 10.1007/s10765-025-03509-5

Davide Menegazzo, Giulia Lombardo, Laura Vallese, Sergio Bobbo

{"title":"Experimental Compressed Liquid Density Measurements and Correlation of the Binary Mixture {n-Pentane (R601) + Trans-1-chloro-3,3,3-trifluoro-1-propene (R1233zd(E))}","authors":"Davide Menegazzo, Giulia Lombardo, Laura Vallese, Sergio Bobbo","doi":"10.1007/s10765-025-03509-5","DOIUrl":"10.1007/s10765-025-03509-5","url":null,"abstract":"<div>Regulations like the F-gas Regulation (EU) 2024/573 and the Kigali Amendment to the Montreal Protocol, along with efforts to mitigate climate change, drive research into alternatives to fluorinated greenhouse gases for high-temperature heat pumps and power generation. Ideal refrigerants should have low GWP, high efficiency, non-flammability, non-toxicity, material compatibility and cost effectiveness. HCFOs have emerged as promising candidates, both as pure fluids and in mixtures with HCs. These blends show efficiency and potential non-flammability for high-temperature applications, but experimental data on their thermophysical properties remain scarce. This study presents the first experimental measurements on the {n-pentane (R601) + trans-1-chloro-3,3,3-trifluoro-1-propene (R1233zd(E))} binary system. In particular, the compressed liquid density of three mixture compositions have been measured employing a vibrating tube densimeter within the temperature range from 283.15 K to 423.15 K and at pressures ranging from 1 MPa to 12 MPa. A novel technique was applied to ensure a combined uncertainty (k=2) not greater than 0.0003 mol(cdot)mol(^{-1}) in the mixture composition, leading to final combined uncertainty (k=2) on the liquid density of no more than 0.2%. Finally, a new mixture model based on the Helmholtz-energy-explicit Equation of State has been developed from such experimental data. This model accurately represents the behaviour of the binary mixture, enhancing the available understanding of its thermodynamic properties.</div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 3","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-025-03509-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108045","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}

引用次数: 0

The Laser Flash Technique: A Widespread Technology for Measurement of the Thermal Diffusivity of Solids and Liquids

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-02-03 DOI: 10.1007/s10765-025-03510-y

Juergen Blumm

{"title":"The Laser Flash Technique: A Widespread Technology for Measurement of the Thermal Diffusivity of Solids and Liquids","authors":"Juergen Blumm","doi":"10.1007/s10765-025-03510-y","DOIUrl":"10.1007/s10765-025-03510-y","url":null,"abstract":"<div>Flash methods such as laser or light flash have developed to be one of the most commonly used techniques for measuring the thermal diffusivity and thermal conductivity of various kinds of solids such as metals, ceramics, polymers, graphite and composite materials. During a flash test, the front side of a plane-parallel specimen is heated by a short laser or light pulse. The resulting temperature rise on the rear surface of the specimen is measured versus time. By evaluating this temperature rise, the thermal diffusivity of material can be determined without requirement for any sensor calibration. Fast measurement times, easy adaption to carrying out temperature-dependent tests, easy specimen preparation, small specimen dimensions, and high reliability are only some of the advantages of this non-contact measurement technique. The method allows also for measurement of the specific heat capacity by a comparative method and therefore, thermal conductivity determination. This requires calibration of the signal height by employing a specific heat capacity standard material with comparable specimen geometries and surface emissivities. Since the introduction of the method in 1961, significant improvements have been made on the hardware, the mathematical treatment of the detector signals and the general instrument operation via the software. Presented in this work is an overview of the working principle, the mathematical background, the general uncertainty of the method, results of comparative tests and some typical application examples for the flash technique.</div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 3","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143107951","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}

引用次数: 0

Transport Property Predictions for CH4/H2/CO/CO2/N2/H2O Mixtures Based on Excluded Volume Without Fitting Parameters

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-02-01 DOI: 10.1007/s10765-024-03482-5

Ali Aminian

{"title":"Transport Property Predictions for CH4/H2/CO/CO2/N2/H2O Mixtures Based on Excluded Volume Without Fitting Parameters","authors":"Ali Aminian","doi":"10.1007/s10765-024-03482-5","DOIUrl":"10.1007/s10765-024-03482-5","url":null,"abstract":"<div>The knowledge of viscosity and thermal conductivity of molecular fluids in the dense phase, which could also accommodate mixture properties, are of great importance in chemical, aerospace, and syngas technology. In this study, we tend to offer a formulation that only needs “excluded volume” to calculate the transport properties for polyatomic fluids and fluid mixtures. The formulations allow calculation of transport properties over a wide range of temperature, pressure, and composition including the supercritical region. Based on the Chapman–Enskog equations, the low-density properties were taken to be corrected for the dense fluid region in which it has been proposed an excluded volume term whose value can be calculated using an equation of state, e.g., the Statistical Association Fluid Theory (SAFT) Equation of State (EoS). The models were tested for different mixtures comprising CH4/H2/CO/CO2/N2/H2O molecules to calculate their transport properties over the entire fluid phase region. Furthermore, comparisons were made between the predicted values and existing experimental data or extended corresponding–states of law equation for mixtures.</div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 3","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108119","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}

引用次数: 0

Enhancement of Thermal Conductivity of Paraffin PCM with Metal Foams

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-01-30 DOI: 10.1007/s10765-024-03500-6

Eleonora Baccega, Laura Vallese, Michele Bottarelli

{"title":"Enhancement of Thermal Conductivity of Paraffin PCM with Metal Foams","authors":"Eleonora Baccega, Laura Vallese, Michele Bottarelli","doi":"10.1007/s10765-024-03500-6","DOIUrl":"10.1007/s10765-024-03500-6","url":null,"abstract":"<div>Paraffin PCMs (Phase Change Materials) are widely used for thermal energy storage due to their homogeneity and stability. However, one of their main drawbacks lies in their poor thermal conductivity, usually around 0.2 W·m−1·K−1. In the context of the Horizon Europe project “ECHO” (Efficient Compact Modular Thermal Energy Storage System), the integration of metal foams within paraffin PCM was investigated in order to increase the overall thermal conductivity, thus speeding up the melting and solidification phases. Tests were carried out in a thermostatic bath using at first pure aluminum foam. Then, considering the consistent price these materials usually have, other commercial and much cheaper foams were also tested, namely a stainless-steel foam and a brass one. As expected, pure aluminum had the best performance among the three foams. However, the behavior of the brass foam was quite close to that of pure aluminum, which means that interesting improvements can be achieved even with low-cost materials. As regards the stainless-steel foam, barely any improvement is observed.</div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 3","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-024-03500-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110067","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}

引用次数: 0

Densities, Speeds of Sound and Refractive Indices for Binary Mixtures of Acetonitrile + Alkyl-Substituted Butylbenzenes: Experimental and Modeling Study

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-01-30 DOI: 10.1007/s10765-024-03496-z

Dana Drăgoescu, Ariel Hernández, Alexander Shchamialiou

{"title":"Densities, Speeds of Sound and Refractive Indices for Binary Mixtures of Acetonitrile + Alkyl-Substituted Butylbenzenes: Experimental and Modeling Study","authors":"Dana Drăgoescu, Ariel Hernández, Alexander Shchamialiou","doi":"10.1007/s10765-024-03496-z","DOIUrl":"10.1007/s10765-024-03496-z","url":null,"abstract":"<div>The experimental data of densities, ρ, speeds of sound, u, and refractive indices, nD, are reported for three binary mixtures of acetonitrile + aromatic hydrocarbons, namely: acetonitrile + n-butylbenzene, acetonitrile + sec-butylbenzene and acetonitrile + tert-butylbenzene, respectively, at T = (298.15, 303.15, 308.15, 313.15, and 318.15) K, on the entire composition ranges and under atmospheric pressure, p = 0.1 MPa. The values obtained from experimental measurements have been correlated by the Jouyban-Acree model with good accuracy. The excess molar volumes, ({V}_{m}^{E}), excess speeds of sound, uE, excess isentropic compressibilities, ({kappa }_{S}), excess molar isentropic compressibilities, ({K}_{S,m}^{E}), refractive index deviations, ΔnD, and excess molar refractions, ({R}_{m}^{E}), have been calculated from experimental data. For each of the studied mixtures, the excess or deviation properties have been correlated with the Redlich–Kister polynomial equation and the coefficients of correlations were reported. In this manuscript, Perturbed Chain Statistical Associating Fluid Theory Equation of State (PC-SAFT EoS) was used for modeling the density as predictive approach. On the other hand, PC-SAFT + two models were used for calculate the speed of sound of binary mixtures, and PC-SAFT + four mixing rules were used for compute the refractive index of binary mixtures.</div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 3","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110038","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}

引用次数: 0

Densities and Viscosities of Polyoxymethylene Dimethyl Ether with Methyl Decanoate, Methyl Dodecanoate, and Methyl Tetradecanoate

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-01-30 DOI: 10.1007/s10765-025-03506-8

Guofan Jin, Jianrong Shi, Xiaopo Wang

引用次数: 0

Hybrid Nanofluids-Based Direct Absorption Solar Collector: An Experimental Approach

IF 2.5 4区工程技术

International Journal of Thermophysics Pub Date : 2025-01-30 DOI: 10.1007/s10765-025-03507-7

Gabriela Huminic, Angel Huminic, Claudiu Fleacă, Florian Dumitrache

{"title":"Hybrid Nanofluids-Based Direct Absorption Solar Collector: An Experimental Approach","authors":"Gabriela Huminic, Angel Huminic, Claudiu Fleacă, Florian Dumitrache","doi":"10.1007/s10765-025-03507-7","DOIUrl":"10.1007/s10765-025-03507-7","url":null,"abstract":"<div>In the last years, studies have demonstrated the potential of hybrid nanofluids to enhance the performance of direct absorption solar collectors. These working fluids containing noble metals (gold, silver) are known for their local surface plasmon resonance which is the main cause for the increased absorption within the solar spectrum. In the current paper, new direct absorption solar collectors prototypes using water-ethylene glycol solution and 0.1 wt.% silver nanoparticles + reduced graphene oxide dispersed in water-ethylene glycol mixture were designed, built, and tested under outdoor conditions, at two flow rates (1.0 and 1.5 l·min−1) and two inlet temperatures (20 (^circ{rm C}) and 30 (^circ{rm C})), over several days in September 2023, at Brasov, Romania. The results suggested that by using silver nanoparticles + reduced graphene oxide nanofluid, the efficiency is improved related to water-ethylene glycol solution. The maximum relative enhancement in efficiency was 16.72% related to the base fluid. Also, at 1.0 l·min−1, the instantaneous and accumulative energies delivered were about 13.51% and 42.91%, respectively, higher than the water-ethylene glycol solution. Finally, the current results were compared to other research carried out on full-scale direct absorption solar collectors tested in outdoor conditions.</div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"46 3","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-025-03507-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110069","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}

引用次数: 0