Journal of Engineering Thermophysics最新文献_第7页

The Impact of TiO({}_{mathbf{2}}) Nanoparticles on the Freezing Properties of Droplets tio2 ({}_{mathbf{2}})纳米颗粒对液滴冻结性能的影响

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S1810232825020146

Z. Zhang, T. Q. Yang, S. Mehendale, T. Y. Duan, M. M. Wang, N. Sun, S. Q. Wang, J. J. Tian

{"title":"The Impact of TiO({}_{mathbf{2}}) Nanoparticles on the Freezing Properties of Droplets","authors":"Z. Zhang, T. Q. Yang, S. Mehendale, T. Y. Duan, M. M. Wang, N. Sun, S. Q. Wang, J. J. Tian","doi":"10.1134/S1810232825020146","DOIUrl":"10.1134/S1810232825020146","url":null,"abstract":"To investigate the stationary nanofluid droplets effects of\u0000substrate surface temperature and particle concentration on the\u0000freezing time, deformation, and droplet contact angle during the\u0000freezing process, high-speed CCD image observation was used to\u0000study the morphological changes during the freezing process of\u0000(TiO({}_{2})–H({}_{2})O) nanodroplets. Nanoparticle droplets were\u0000prepared in this study using magnetic stirring and ultrasonic\u0000mixing. Three substrate surface temperatures (268, 265, and 263 K)\u0000and four concentrations of TiO({}_{2}) nanoparticles (5, 10, 30, and\u000050 mg/mL) were considered. The findings demonstrate that the\u0000addition of nanoparticles will result in the droplets appearing\u0000sanded, a considerable change in the form of the droplet tip, and\u0000a decrease in the release of bubbles upon freezing. The increase\u0000in supercooling at high concentrations ((>5) mg/mL) causes the\u0000droplet height to rise, its volume to expand upon freezing, and\u0000its shape to shift from ‘‘peach-core’’ to ‘‘cone-like.’’ When\u0000TiO({}_{2}) nanoparticles were added, the droplets’ longitudinal\u0000morphology changed throughout the freezing process, but lateral\u0000diffusion was unaffected, even though the contact angle (theta)\u0000marginally shrank as concentration increased. The droplets with\u0000the lowest concentration of TiO({}_{2}) particles exhibit the\u0000highest longitudinal deformation rate (alpha) during the droplet\u0000freezing process. As the subcooling degree increases, (alpha)\u0000also rises and reaches its maximum at 263 K or 22.26(%), but as\u0000the concentration of nanoparticles grows, (alpha) drops, and so\u0000does the coefficient of segregation, (gamma).","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 2","pages":"386 - 400"},"PeriodicalIF":1.4,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145296874","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

Cryostat with Enhanced Thermal Insulation for Advanced Superconducting Devices 低温恒温器与增强绝热先进超导器件

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S1810232825020122

R. I. Ilyasov, K. L. Kovalev, Yu. I. Kovan, L. A. Egoshkina, D. S. Dezhin

{"title":"Cryostat with Enhanced Thermal Insulation for Advanced Superconducting Devices","authors":"R. I. Ilyasov, K. L. Kovalev, Yu. I. Kovan, L. A. Egoshkina, D. S. Dezhin","doi":"10.1134/S1810232825020122","DOIUrl":"10.1134/S1810232825020122","url":null,"abstract":"This article describes in detail the design of a cryostat developed by the authors, which has high thermal insulation properties. The development is based on the possibility of performing phase transitions of the working fluid from a gaseous state to a liquid, and then to a solid in a hermetic cryostat jacket. The processes of phase transitions occurring in the jacket should be considered as isochoric, since they occur in a closed volume of the jacket. The increase in thermal insulation properties is ensured by the fact that the hermetic space of the jacket is filled with a working fluid in the form of a heavy monatomic gas with low heat capacity and static thermal conductivity (for example, xenon, krypton or an azeotropic mixture of gases or freons). These gases have a condensation and crystallization temperature higher than the temperature of the cryogenic liquid stored in the inner vessel (e.g., helium, hydrogen, neon, nitrogen, oxygen, argon, methane, liquefied natural gas). The cryostat design is described in detail, calculations are given to justify the rational choice of the working fluid for filling the cryostat jacket. When operating this cryostat, there is no need for vacuum pumps, as well as operating costs for maintaining a vacuum. Partial preservation of thermal insulation properties is also ensured in the event of an emergency depressurization of the jacket from the outside. In addition, the operational safety of storing explosive or toxic cryogenic liquids is increased.","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 2","pages":"367 - 376"},"PeriodicalIF":1.4,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145296575","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

Optimization of Spacecraft Thermal Shield for Crew Return after Lunar Mission 面向登月任务返航人员的航天器隔热罩优化

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S1810232825020018

A. V. Nenarokomov, D. L. Reviznikov, I. A. Nikolichev, M. O. Salosina, A. S. Grinenko

引用次数: 0

Flow Thermodynamic Potential for Gas Systems 气体系统的流动热力学势

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S181023282502002X

V. T. Volov

引用次数: 0

Influence of Monodisperse Backfill Particle Diameter on Oscillations of Superfluid Helium–Vapor Interface in a U-Shaped Channel 单分散充填体粒径对u型通道内超流氦气界面振荡的影响

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S1810232825020043

Yu. Yu. Puzina, A. P. Kryukov

引用次数: 0

Droplet Impact on a Heated Surface: Influence of Key Factors on Heat Transfer 液滴对受热表面的冲击：关键因素对传热的影响

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S1810232825020092

I. S. Vozhakov, S. Y. Misyura, V. S. Morozov, A. A. Lukyanov

{"title":"Droplet Impact on a Heated Surface: Influence of Key Factors on Heat Transfer","authors":"I. S. Vozhakov, S. Y. Misyura, V. S. Morozov, A. A. Lukyanov","doi":"10.1134/S1810232825020092","DOIUrl":"10.1134/S1810232825020092","url":null,"abstract":"The review focuses on the study of heat and mass transfer processes in liquid droplets, which play a critical role in various natural and technological systems. The main mechanisms of heat transfer and mass transport in droplets are considered, including convective and diffusive transport, evaporation, condensation, and interactions between the droplet and its surrounding environment. Unresolved challenges remain in deriving simplified estimates for unsteady, non-isothermal heat transfer in liquid droplets under rapidly changing boundary conditions on free surfaces. The review proposes several approaches to assess the intensity of heat and mass transfer. Factors influencing heat and mass transfer intensity, such as droplet size, temperature, liquid composition, gas properties, and external conditions, are analyzed. Theoretical approaches and models commonly used to describe these processes, as well as experimental research results, are presented. This review highlights the relevance of the problem and outlines prospects for further research into heat and mass transfer in droplets to improve technologies and deepen fundamental knowledge of interfacial processes. Understanding the physical mechanisms and accurately predicting droplet behavior and heat transfer are essential for advancing modern technologies, including materials science, spray cooling of microelectronics, inkjet printing, fuel droplet atomization in internal combustion engines, as well as applications in medicine (disease diagnostics) and biotechnology (micro- and mini-reactors).","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 2","pages":"321 - 332"},"PeriodicalIF":1.4,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145296427","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

Thermal Buoyancy and Radiation Effects on Nanofluid Flow over Shrinking/Stretching Porous Surface 热浮力和辐射对纳米流体在收缩/拉伸多孔表面流动的影响

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S1810232825020183

U. S. Mahabaleshwar, G. V. Bognar, A. B. Vishalakshi, K. M. Nihaal, B. A. Sunden, G. Lorenzini

引用次数: 0

LBM Simulation for Analyzing the Performance of Sawtooth Microchannels with Positive and Negative Ramps 正负斜坡锯齿微通道性能分析的LBM仿真

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S1810232825020158

A. Khanom, M. N. Sohel, R. Biswas, M. M. Molla, M. A. Taher

{"title":"LBM Simulation for Analyzing the Performance of Sawtooth Microchannels with Positive and Negative Ramps","authors":"A. Khanom, M. N. Sohel, R. Biswas, M. M. Molla, M. A. Taher","doi":"10.1134/S1810232825020158","DOIUrl":"10.1134/S1810232825020158","url":null,"abstract":"This study investigates thermal and fluid behaviors in smooth microchannels under slip flow regime using an alternative numerical technique namely the thermal lattice Boltzmann method (TLBM). This method is based on D2Q9 model with lattice-BGK (Bhatnagar–Gross–Krook) approximations. In this procedure, an internal energy distribution function uses to calculate temperature, and a momentum distribution function to evaluate macroscopic quantities like density, pressure and velocity etc. With these macroscopic quantities, the important physical properties such as the average flow friction, mass flow rate, and the heat transfer rate are investigated and discussed for different governing parameters. The relative ramp heights (0(%)–10(%)) and Knudsen number (Kn) (0.01–0.10) are the most important parameters in this study. The average frictional resistance decrease with increasing Kn but increasing with ramps height, whereas the mass flow rate reduced both for ramps height and Kn. Moreover, the heat transfer rate decreased significantly with Kn and very slowly with ramps height. Another important properties, the combined effect of thermal and hydraulic properties called the coefficient of performance (COP) is studied to compare the efficiency of different microchannels. COP decreases with increasing ramp height as well as Kn. Optimal performance is observed with very low ramp heights. The microchannel with negative ramps perform better than positive ramps case. The COP of sawtooth microchannels is calculated to compare with the friction (pressure drop) and heat transfer of smooth microchannel. Finally, the obtained result is compared, and an excellent agreement is found with published work.","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 2","pages":"401 - 413"},"PeriodicalIF":1.4,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145296475","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

Separation of Microparticles by Size in an Electrodynamic Field 在电动力场中按大小分离微粒

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S1810232825020134

S. V. Kalashnikov, A. V. Nomoev, T. A. Chimytov

引用次数: 0

Experimental Study of Heat Transfer in Single-Nozzle Non-Boiling Spray Cooling 单喷嘴非沸腾喷雾冷却换热实验研究

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-10-16 DOI: 10.1134/S181023282502016X

A. Nazarov, E. Starinskaya, A. Zherdev, N. Mis’kiv

{"title":"Experimental Study of Heat Transfer in Single-Nozzle Non-Boiling Spray Cooling","authors":"A. Nazarov, E. Starinskaya, A. Zherdev, N. Mis’kiv","doi":"10.1134/S181023282502016X","DOIUrl":"10.1134/S181023282502016X","url":null,"abstract":"Spray cooling is a promising method of heat removal and is widely used in various industries and technologies, e.g., cooling of electronic components, metallurgy, aerospace engineering, and power engineering. However, its efficiency depends on many factors, including the characteristics of the spray flow, properties of the working fluid, and parameters of the heat transfer surface. Despite the intensive research in this area, many aspects of the influence of the nozzle geometry, droplet distribution, and heat transfer modes remain understudied. The present work is aimed at filling these gaps, which will enable optimization of heat transfer processes and improvement of the efficiency of cooling systems. Parameters such as the volume flow rate of liquid, droplet diameter and velocity, and their influence on the heat transfer process were studied in this work. The obtained experimental data were compared with known literature correlations for the non-boiling mode. The measured values of the flow velocity and the Sauter diameter of droplets generated by the nozzle were compared with theoretical calculations.","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 2","pages":"414 - 427"},"PeriodicalIF":1.4,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145296420","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