International Journal of Thermophysics最新文献

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Low-Temperature Study of Thermodynamic and Rheological Properties of Ethylene Glycol Including the Supercooled Region 包括过冷区在内的乙二醇热力学和流变学特性低温研究
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-09-12 DOI: 10.1007/s10765-024-03426-z
Matthew Leonard, Bratoljub H. Milosavljevic
{"title":"Low-Temperature Study of Thermodynamic and Rheological Properties of Ethylene Glycol Including the Supercooled Region","authors":"Matthew Leonard,&nbsp;Bratoljub H. Milosavljevic","doi":"10.1007/s10765-024-03426-z","DOIUrl":"10.1007/s10765-024-03426-z","url":null,"abstract":"<div><p>A comprehensive discussion/analysis of the published viscosity data of ethylene glycol, EG, in the temperature range from 260 (just above the freezing point) to 465 K was recently reported in this journal. It was found that some of the reported data sets significantly deviate from each other, and the largest discrepancies were found at the lower end of the temperature interval examined (Mebelli et al. in Int. J. Thermophys. 42:116, 2021). Hence, in this work, the densities and viscosities of EG were measured in the temperature interval starting in the supercooled region at 248 and extending up to 313 K. Well-established experimental techniques were employed, that is, pycnometry and laminar flow viscometry, the relative precision of which were better than 0.5 and 0.5 %, respectively. The density was found to linearly depend on temperature in the temperature range studied; the cubic expansion coefficient was found to be γ = (5.20 + 3.99 × 10<sup>−3</sup> T K<sup>− 1</sup>) × 10<sup>−4</sup> K<sup>−1</sup>. When our experimental density data were applied to calculate the dynamic viscosity values using the correlation dependence published in the aforementioned review (Mebelli et al. in Int. J. Thermophys. 42:116, 2021), the discrepancy between our experimental data and the calculated values is less than 2 % above the freezing point; however, in the supercooled region, the discrepancy increases up to 4 % at 248 K. When the cooling rate is higher than 10 K min<sup>− 1</sup> and the sample mass is less than 5 mg, EG does not freeze; it undergoes glass formation (Tg =  − 121 °C) as revealed in our DSC experiments. The Arrhenius plot for viscosity data was found to be nonlinear; from the Angell plot, it was concluded that EG is a moderately fragile liquid with the fragility index = 70.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"45 9","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196916","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
Recent Achievements in Heat Transfer Enhancement with Hybrid Nanofluid in Heat Exchangers: A Comprehensive Review 利用混合纳米流体增强热交换器传热的最新成果:全面回顾
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-09-12 DOI: 10.1007/s10765-024-03428-x
Mudhar A. Al-Obaidi, Farhan Lafta Rashid, Musaab K. Rasheed, Hakim S. Sultan Aljibori, Hayder I. Mohammed, Ali Jafer Mahdi, Shabbir Ahmad, Khaled Al-Farhany, Iqbal M. Mujtaba
{"title":"Recent Achievements in Heat Transfer Enhancement with Hybrid Nanofluid in Heat Exchangers: A Comprehensive Review","authors":"Mudhar A. Al-Obaidi,&nbsp;Farhan Lafta Rashid,&nbsp;Musaab K. Rasheed,&nbsp;Hakim S. Sultan Aljibori,&nbsp;Hayder I. Mohammed,&nbsp;Ali Jafer Mahdi,&nbsp;Shabbir Ahmad,&nbsp;Khaled Al-Farhany,&nbsp;Iqbal M. Mujtaba","doi":"10.1007/s10765-024-03428-x","DOIUrl":"10.1007/s10765-024-03428-x","url":null,"abstract":"<div><p>The potential of hybrid nanofluids to boost thermal efficiency of heat exchanger systems is the focus of this review study. The primary focus is on addressing the associated issues of nanoparticle clumping, system obstruction, and reduced efficacy of heat exchanger due to increased fluid thickness. Accordingly, this review intends to demonstrate the innovative practices (experimentally and theoretically) that helps improving the heat transfer and thermal performance of heat exchangers. In this regard, a critical analysis is conducted to appraise the experimental and numerical simulations, which introduce the impact of different nanoparticle concentrations and compositions on heat exchanger thermal performance. The findings of this review has shown that the hybrid nanofluid of CuO–Cu/water has the greatest thermal performance factor (1.065), following Al<sub>2</sub>O<sub>3</sub>–Cu/water (1.055), and Cu–TiO<sub>2</sub>/water (1.039). Also, the utilization of turbulator heat exchangers has enabled improving the thermal performance by 126 % with a 6 % rise in volume fraction at the maximum Reynolds number. This study underlines the need for further research into novel nanomaterial combinations, fine-tuning of fluid characteristic, and comprehensive stability assessments to enhance the utilization of hybrid nanofluids in heat exchanger systems. Finally, discussions of limitations associated with such systems and proposed potential solutions will lead to a valuable contribution in the possible future development of cost-effective heat exchanger systems.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"45 9","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196919","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
Expansivity of Fused Quartz Glass Measured Within (6 times 10^{-10},text{K}^{-1}) 测量到的熔融石英玻璃的膨胀率在 $$6 次 10^{-10},text{K}^{-1}$$ 范围内
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-09-11 DOI: 10.1007/s10765-024-03422-3
Patrick F. Egan
{"title":"Expansivity of Fused Quartz Glass Measured Within (6 times 10^{-10},text{K}^{-1})","authors":"Patrick F. Egan","doi":"10.1007/s10765-024-03422-3","DOIUrl":"10.1007/s10765-024-03422-3","url":null,"abstract":"<div><p>A method is described to measure the thermal expansion coefficient of fused quartz glass. The measurement principle is to monitor the change in resonance frequency of a Fabry–Perot cavity as its temperature changes; the Fabry–Perot cavity is made from fused quartz glass. The standard uncertainty in the measurement was less than 0.6 <span>((textrm{nm}{cdot } textrm{m}^{-1}){cdot }textrm{K}^{-1})</span>, or 0.15 %. The limit on performance is arguably uncertainty in the reflection phase-shift temperature dependence, because neither thermooptic nor thermal expansion coefficients of thin-film coatings are reliably known. However, several other uncertainty contributors are at the same level of magnitude, and so any improvement in performance would entail significant effort. Furthermore, measurements of three different samples revealed that material inhomogeneity leads to differences in the effective thermal expansion coefficient of fused quartz; inhomogeneity in thermal expansion among samples is 24 times larger than the measurement uncertainty in a single sample.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"45 9","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-024-03422-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225066","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
Peculiarity of Superheated Hydrocarbons: Jump in Heat Transfer Due to Micro-additives of Moisture 过热碳氢化合物的特殊性:水分微量添加剂导致的传热跃迁
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-09-09 DOI: 10.1007/s10765-024-03427-y
A. V. Melkikh, P. V. Skripov
{"title":"Peculiarity of Superheated Hydrocarbons: Jump in Heat Transfer Due to Micro-additives of Moisture","authors":"A. V. Melkikh,&nbsp;P. V. Skripov","doi":"10.1007/s10765-024-03427-y","DOIUrl":"10.1007/s10765-024-03427-y","url":null,"abstract":"<div><p>The aim of the present work is to draw the attention to an unusual object of study, namely, heat transfer in short-term superheated hydrocarbons with micro-additives of moisture. We discuss the reasons for effect of the increase in the heat transfer coefficient to samples of saturated hydrocarbons having a moisture content of 15 mg⋅kg<sup>−1</sup> to 35 mg⋅kg<sup>−1</sup>, which is unexpectedly strong (up to 10 %) with respect to pure hydrocarbons. This effect was discovered in experiments on pulse heating of a wire probe in a substance with characteristic times of 1 ms to 10 ms. We have developed a model based on the assumption of the role of dissolved water clusters in initiating fluid motion in the course of short-term superheating of the base fluid with respect to the liquid–vapor equilibrium temperature. Depending on the degree of superheating and pressure, the values predicted by the model for the increment of the heat transfer coefficient due to micro-additives of moisture are qualitatively consistent with the data obtained from the pulse experiments. The results of this study clarify the specific features of the superheated states of composite fluids, as well as contribute to developing methods for controlling the heat flux by micro-additives of a partially soluble component to the heat carrier.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"45 9","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196918","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
Equilibrium Solubility of Sulfadiazine in (Acetonitrile + Ethanol) Mixtures: Determination, Correlation, Dissolution Thermodynamics, and Preferential Solvation 磺胺嘧啶在(乙腈+乙醇)混合物中的平衡溶解度:测定、相关性、溶解热力学和优先溶解度
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-09-02 DOI: 10.1007/s10765-024-03405-4
Daniel Ricardo Delgado, Claudia Patricia Ortiz, Fleming Martínez, Abolghasem Jouyban
{"title":"Equilibrium Solubility of Sulfadiazine in (Acetonitrile + Ethanol) Mixtures: Determination, Correlation, Dissolution Thermodynamics, and Preferential Solvation","authors":"Daniel Ricardo Delgado,&nbsp;Claudia Patricia Ortiz,&nbsp;Fleming Martínez,&nbsp;Abolghasem Jouyban","doi":"10.1007/s10765-024-03405-4","DOIUrl":"10.1007/s10765-024-03405-4","url":null,"abstract":"<div><p>The equilibrium solubility of sulfadiazine (SD, 3) in several {acetonitrile (MeCN) + ethanol (EtOH)} mixtures at nine temperatures from <i>T</i>/K = (278.15 K to 318.15) has been determined by following the shake flask method. SD solubility increased with temperature-arising as well as with the MeCN proportion-increasing in the mixtures. Thus, <i>x</i><sub>3</sub> increased from 7.74 × 10<sup>−5</sup> in neat EtOH to 6.20 × 10<sup>−4</sup> in neat MeCN at <i>T</i>/K = 298.15. SD solubility was adequately correlated with a second-order multivariate equation as function of both mixtures composition and temperature. Moreover, two models including the Jouyban–Acree and Jouyban–Acree–van’t Hoff models were applied to mathematical SD solubility data modeling in solvent mixtures. The accuracy of each model is investigated by the mean relative deviations (MRD%) of the back-calculated solubility. A full predictive model was provided by training the Jouyban–Acree–van’t Hoff model with only seven experimental solubility data which provided excellent predictions with the MRD% of 3.7 %. All used models show a low MRD% values (&lt; 4.0 %) for the calculated data indicating a good correlation of SD solubility data with the given mathematical models. By means of the van’t Hoff and Gibbs equations, the apparent thermodynamic quantities relative to SD dissolution and mixing processes, namely Gibbs energies, enthalpies, and entropies, were calculated and reported. Apparent dissolution quantities of SD were positive in all cases indicating endothermic and entropy-driven behaviors. A non-linear enthalpy–entropy relationship was observed for SD in the plot of SD dissolution enthalpy <i>vs.</i> Gibbs energy. Observed trend exhibits negative slope in the composition from neat EtOH to the mixture of 0.05 in mass fraction of MeCN indicating entropy-driving mechanism for this SD transfer process. Moreover, variant but positive slopes were found in the composition interval of 0.05 &lt; <i>w</i><sub>1</sub> &lt; 1.00 indicating enthalpy-driving mechanism for these SD transfer processes. Furthermore, the preferential solvation of SD by MeCN or EtOH was analyzed by using the inverse Kirkwood–Buff integrals. Thus, SD is preferentially solvated by EtOH molecules in EtOH-rich mixtures but preferentially solvated by MeCN in MeCN-rich mixtures. In this way, this research expands the literature investigations about the solubility of SD in some non-aqueous cosolvent mixtures conformed by MeCN and other alcohols.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"45 9","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-024-03405-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196920","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
Mutual and Thermal Diffusivities in Binary Mixtures of Polystyrene with Dissolved N2 or CO2 by Dynamic Light Scattering 通过动态光散射测量聚苯乙烯与溶解的 N2 或 CO2 二元混合物的相互扩散率和热扩散率
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-09-02 DOI: 10.1007/s10765-024-03418-z
Patrick S. Schmidt, Julius H. Jander, Fatima Alhadi, Marcel Ratka, Christian Bonten, Tobias Klein, Andreas P. Fröba
{"title":"Mutual and Thermal Diffusivities in Binary Mixtures of Polystyrene with Dissolved N2 or CO2 by Dynamic Light Scattering","authors":"Patrick S. Schmidt,&nbsp;Julius H. Jander,&nbsp;Fatima Alhadi,&nbsp;Marcel Ratka,&nbsp;Christian Bonten,&nbsp;Tobias Klein,&nbsp;Andreas P. Fröba","doi":"10.1007/s10765-024-03418-z","DOIUrl":"10.1007/s10765-024-03418-z","url":null,"abstract":"<div><p>In physical foaming processes of thermoplastics, a liquid mixture consisting of a molten polymer with a dissolved blowing agent is extruded through a die or injected into a mold. The morphology of the foam matrix strongly depends on the mutual diffusion coefficient <i>D</i><sub>11</sub> of the liquid polymer-blowing agent mixture. For a better understanding of the underlying physical mechanisms during the foaming process and the development of corresponding models, accurate knowledge of <i>D</i><sub>11</sub> is needed. This work reports on the simultaneous measurement of <i>D</i><sub>11</sub> and the thermal diffusivity <i>a</i> of liquid mixtures consisting of polystyrene melts with dissolved nitrogen (N<sub>2</sub>) or carbon dioxide (CO<sub>2</sub>) at mass fractions <i>w</i><sub>solute</sub> up to 0.003 or 0.02 and temperatures <i>T</i> between (433 and 533) K using dynamic light scattering (DLS). The determined <i>D</i><sub>11</sub> range is between (1 and 4) × 10<sup>9</sup> m<sup>2</sup>⋅s<sup>−1</sup> and are slightly larger for the mixtures containing N<sub>2</sub> at a given <i>T</i> and <i>w</i><sub>solute</sub>. <i>D</i><sub>11</sub> could be determined with an average expanded relative uncertainty of 18%. Considering all investigated state points and the achieved experimental uncertainties, both <i>D</i><sub>11</sub> and <i>a</i> are independent on the amount of dissolved gas, despite relatively large mole fractions of the dissolved blowing agents <i>x</i><sub>solute</sub> of 0.997 and 0.93.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"45 9","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-024-03418-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196943","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
Thermal Diffusivity of Solid and Liquid 304 Stainless Steel, Iron, and Zirconium 固态和液态 304 不锈钢、铁和锆的热扩散率
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-08-27 DOI: 10.1007/s10765-024-03417-0
Jad Houssein, Thomas Pierre, Mickaël Courtois, Muriel Carin
{"title":"Thermal Diffusivity of Solid and Liquid 304 Stainless Steel, Iron, and Zirconium","authors":"Jad Houssein,&nbsp;Thomas Pierre,&nbsp;Mickaël Courtois,&nbsp;Muriel Carin","doi":"10.1007/s10765-024-03417-0","DOIUrl":"10.1007/s10765-024-03417-0","url":null,"abstract":"<div><p>Measurement of the thermophysical properties of liquid metals is a highly challenging task due to numerous problems encountered above the fusion point. Properties such as density and surface tension have been widely investigated, while few studies address thermal diffusivity. In this paper we describe an original methodology for estimating the thermal diffusivity of metals in the liquid state. The proposed experimental setup is based on the traditional flash method. Its design ensures that samples of liquid metal are self-contained, preventing contamination and allowing measurements at high temperature. Results for both solid and liquid iron and 304 stainless steel are presented and compared to data suggested by the literature for validation. Then, for the first time, thermal diffusivity measurement of liquid zirconium is performed giving results up to 2450 K. Giving the high sensitivity of the results to the thickness variation we propose a numerical approach to deal with this issue.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"45 9","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196948","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
Development of A Simple 1-T Dew-Point Generator 开发简单的 1-T 露点发生器
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-08-27 DOI: 10.1007/s10765-024-03420-5
Arfan Sindhu Tistomo, Aditya Achmadi, Melati Azizka Fajria, Sri Ningsih Yazana Pakpahan,  Arlan, Mareta Dwi Anastasya, Kelvin Sapta Dewantara, Muhammad Azzumar, Yonan Prihhapso, Gigin Ginanjar, Sparisoma Viridi, Muhammad Miftahul Munir,  Suprijadi
{"title":"Development of A Simple 1-T Dew-Point Generator","authors":"Arfan Sindhu Tistomo,&nbsp;Aditya Achmadi,&nbsp;Melati Azizka Fajria,&nbsp;Sri Ningsih Yazana Pakpahan,&nbsp; Arlan,&nbsp;Mareta Dwi Anastasya,&nbsp;Kelvin Sapta Dewantara,&nbsp;Muhammad Azzumar,&nbsp;Yonan Prihhapso,&nbsp;Gigin Ginanjar,&nbsp;Sparisoma Viridi,&nbsp;Muhammad Miftahul Munir,&nbsp; Suprijadi","doi":"10.1007/s10765-024-03420-5","DOIUrl":"10.1007/s10765-024-03420-5","url":null,"abstract":"<div><p>A single-temperature-based dew-point generator (DPG), capable of producing air with dew point temperatures ranging from 25 °C to 60 °C, has been developed at SNSU-BSN Indonesia. The air flows through the saturator in a single pass and is controlled by a flow meter to have a maximum flow rate of 1 lpm. The air saturation process is carried out using a bubble aerator capable of producing bubbles ranging in size from below 0.5 mm to several mm in diameter. A heat sink, placed inside the saturator, is used to prevent water splashes from entering the gas outlet and to stabilize the dew point temperature. The impact of the saturator load is also modeled and simulated. The saturator is then placed into a thermostatic bath where heating of the gas outlet tube is performed starting from 5 cm below the water surface to prevent condensation due to environmental temperature influences. This developed saturator system is simple and low cost. The performance test includes a comparison with a high-precision dew-point hygrometer (DPH) and an evaluation of saturator efficiency. The accuracy of the generated dew point temperature is determined by referencing the reference value from the APMP.T-K8 comparison results. The test results are presented in graphical and tabular format along with an example uncertainty budget.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"45 9","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196946","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
Analyzing Heat Transfer: Experimental and Theoretical Studies on Metal Oxide-Based Binary Nanofluid in Mini Hexagonal Tube Heat Sink 分析传热:微型六角管散热器中基于金属氧化物的二元纳米流体的实验和理论研究
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-08-19 DOI: 10.1007/s10765-024-03421-4
G. Sriharan, S. Harikrishnan, Hakan F. Oztop
{"title":"Analyzing Heat Transfer: Experimental and Theoretical Studies on Metal Oxide-Based Binary Nanofluid in Mini Hexagonal Tube Heat Sink","authors":"G. Sriharan,&nbsp;S. Harikrishnan,&nbsp;Hakan F. Oztop","doi":"10.1007/s10765-024-03421-4","DOIUrl":"10.1007/s10765-024-03421-4","url":null,"abstract":"<div><p>The research aimed to explore the thermal performance of a miniature hexagonal tube heat sink (MHTHS) by utilizing three different binary nanofluids. These nanofluids incorporated nanoparticles such as MgO, Al<sub>2</sub>O<sub>3</sub>, and CuO, dispersed in base fluids of de-ionized water (DIW) (80 %) and ethylene glycol (EG) (20 %) at different concentrations (0.5 vol %, 1.0 vol %, 1.5 vol %, and 2.0 vol %). Variations in volume flow rate (VFR) and temperature spanned from 10L/h to 50L/h and 10 °C to 50 °C, respectively. Throughout the study, nanofluids circulated through the hexagonal tube side (HTS) at VFR ranging from 10L/h to 50L/h, while hot DIW flowed through the mini passage (MPS) at a constant VFR of 30L/h. Notably, CuO–DIW/EG nanofluid exhibited an 8.7 % increase in density, and MgO–DIW/EG nanofluids demonstrated a 14 % increase in thermal conductivity at a particle concentration of 2.0 vol %. However, at a higher particle concentration of 2.0 vol %, MgO–DIW/EG nanofluids exhibited a 5.6 % decrease in specific heat. Furthermore, MgO–DIW/EG nanofluids displayed a 79.6 % increase in heat transfer coefficient and a 66.7 % increase in Nusselt number. Although the pumping power and friction factor showed 5.1 % to 20.4 % and 7.5 % increases in particle concentration and Reynolds number, this negative impact did not affect the overall thermal performance of the heat sink. Finally, the study determined that MgO–DIW/EG nanofluid stands out as the most suitable heat transfer fluid for the heat sink.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"45 9","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196945","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
Demonstration of Thermal Property Determination for a Suspended Wire Using 3ω Method Acquired by a High buffered Multimeter Applying a Discrete Fourier Transformation and a Window Function 使用离散傅里叶变换和窗函数的高缓冲万用表获取的 3ω 方法测定悬挂导线热特性的演示
IF 2.5 4区 工程技术
International Journal of Thermophysics Pub Date : 2024-08-19 DOI: 10.1007/s10765-024-03397-1
Takeshi Takada, Yasuhiro Hasegawa
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