Journal of Engineering Thermophysics最新文献_第4页

Stability of the Wavy Liquid Film Falling above and under an Inclined Plane 波浪状液膜在斜面上下的稳定性

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2026-04-01 DOI: 10.1134/S181023282570033X

Y. Y. Trifonov

{"title":"Stability of the Wavy Liquid Film Falling above and under an Inclined Plane","authors":"Y. Y. Trifonov","doi":"10.1134/S181023282570033X","DOIUrl":"10.1134/S181023282570033X","url":null,"abstract":"The paper is devoted to a theoretical analysis of the nonlinear two-dimensional waves using the Navier–Stokes equations in their full statement. Varying the liquid Reynolds number, the Kapitza number and the wavy regimes wavelength, we consider the wavy liquid film flow both under and above the inclined plane in wide range of the inclination angle. We computed the steady-state traveling waves and carried out an analysis of their linear stability with respect to the disturbances with the same wavelength as the wavelength of the nonlinear solution. Previosly, the stability analysis of the nonlinear waves was carried out only for the case of the flow down a vertical plate. We obtained that the array of the bifurcations lines on plane of two parameters (the Reynolds number, the wavelength) depends essentially on the Kapitza number. The array dependence on the inclinations angle takes place only for the case of the flow under plate at large values of the inclination angle. We obtained dependences of the waves basic characteristics on the problem parameters and presented the typical film thickness profiles. We obtained also parameters where the negative u-velocity appears and where the waves have the closed contour lines of the streamline function. Iinstead of the traveling wave, the liquid drop falls down an inclined plane at these parameters.","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 4","pages":"774 - 787"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579200","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

Magnetically Controlled Slip Flow and Heat Transfer of Immiscible Fluids in Hybrid Porous-Nanofluid Systems 多孔-纳米流体混合体系中非混相流体的磁控滑移流动和传热

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2026-04-01 DOI: 10.1134/S1810232825700328

Jafar Hasnain, Zaheer Abbas, Mariam Shiekh, Nomana Abid, Muhammad Naveed

{"title":"Magnetically Controlled Slip Flow and Heat Transfer of Immiscible Fluids in Hybrid Porous-Nanofluid Systems","authors":"Jafar Hasnain, Zaheer Abbas, Mariam Shiekh, Nomana Abid, Muhammad Naveed","doi":"10.1134/S1810232825700328","DOIUrl":"10.1134/S1810232825700328","url":null,"abstract":"The main aim of this study is to analyze the characteristics of immiscible fluids in the presence of velocity slip and Lorentz force within a vertical channel (VC) embedded in semi-porous media. The channel is divided into two distinct regions: region I contains a viscous fluid with Lorentz force, while region II consists of a nanofluid (NF) in a porous medium, each with unique physical properties. The governing equations for this flow are non-linear ordinary differential equations. Using the perturbation approach, analytical formulas for the velocity and temperature profiles are derived up to the first order. The study thoroughly discusses the physical interpretation of various parameters, including porosity, slip, nanomaterials concentration, magnetic and electric loads, heat absorption/generation coefficients, and thermal conductivity ratios, and illustrates their effects on velocity and temperature distributions through graphs. The insights gained from this study can significantly enhance the efficiency of the cooling system in nuclear reactors, improve the design of heat exchangers, and optimize chemical engineering processes. Additionally, the findings can be applied to develop advanced materials for thermal insulation, design more efficient energy systems, and refine industrial processes such as metal casting and polymer extrusion. The study results also hold relevance for environmental engineering applications, including groundwater hydrology and geothermal energy extraction.","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 4","pages":"844 - 856"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579489","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

Electrochemical Modification of the Metal Mesh Surface for Heat Transfer Enhancement during Boiling of a thin Layer of HFE-7100 HFE-7100薄层沸腾强化传热的金属网表面电化学改性

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2026-04-01 DOI: 10.1134/S1810232825700183

A. E. Brester, D. A. Shvetsov, V. I. Zhukov, A. N. Pavlenko

引用次数: 0

Hydromagnetic Radiative Chemically Reactive Flow along with Soret Effect over a Vertical Porous Plate 垂直多孔板上的磁辐射化学反应流及索雷特效应

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2026-04-01 DOI: 10.1134/S1810232826700025

Srikanta Kumar Patta, J. P. Panda

引用次数: 0

Characteristics and Mechanisms of Droplets Melting on Superhydrophobic Surfaces 超疏水表面液滴熔融特性及机理研究

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2026-04-01 DOI: 10.1134/S1810232826700037

Z. Zhang, S. Q. Huang, S. Mehendale, X. J. Liu, N. N. Xing, J. J. Tian

{"title":"Characteristics and Mechanisms of Droplets Melting on Superhydrophobic Surfaces","authors":"Z. Zhang, S. Q. Huang, S. Mehendale, X. J. Liu, N. N. Xing, J. J. Tian","doi":"10.1134/S1810232826700037","DOIUrl":"10.1134/S1810232826700037","url":null,"abstract":"The melting behavior of frozen droplets on superhydrophobic surfaces and their anti-icing mechanisms were systematically investigated via high-speed imaging and quantitative analysis. Two superhydrophobic surfaces (coating-based and etched-based) and a flat control surface were compared to track droplet morphological evolution, solid-liquid interface dynamics, and key metrics under freezing temperatures (–12 to –3°C) and warming conditions (3 to 23°C). Results show that droplets on superhydrophobic surfaces melt from the bottom, forming a tilted, rotating ice cap. The height coefficient decreases continuously (remaining <1) and stabilizes around 0.875,with the coating-type substrate showing the slowest decay (15% reduction over 40 s) versus the control surface, which declines to 0.70 in only 16 s. Contact angle evolution is non-monotonic—initially decreasing, then increasing. Melting on superhydrophobic surfaces lasts 1–2 times longer than on untreated ones. At –9°C freezing and 13°C warming, the coating surface melts the droplet in 98.0 s, versus 42.4 s for the control. This delay is attributed to the “cavitation effect” of micro/nanostructures forming a gas film barrier that reduces solid–liquid heat transfer, along with reduced interfacial tension from low-surface-energy modification. For identical surface chemistry, the coating with a roughness of 6.513 μm exhibits a 30% greater melting time than the Fluorosilane-modified (FGW) surface with a roughness of 0.114 μm. FGWs also outperform stearic acid-modified (SA) surfaces in delaying melting. Two distinct melting modes have been identified: convection-dominated melting on non-superhydrophobic surfaces, and on superhydrophobic ones, rotation-driven melting governed by interfacial tension–buoyancy interplay, often accompanied by bubble release.","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 4","pages":"913 - 928"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579495","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

Statistical Analysis of Coherent Vortex Structures in Turbulent Flows 湍流中相干涡结构的统计分析

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2026-04-01 DOI: 10.1134/S1810232825700274

B. B. Ilyushin

{"title":"Statistical Analysis of Coherent Vortex Structures in Turbulent Flows","authors":"B. B. Ilyushin","doi":"10.1134/S1810232825700274","DOIUrl":"10.1134/S1810232825700274","url":null,"abstract":"The paper presents a detailed analysis of the statistical structure of the 2D velocity field of coherent vortices in a turbulent flow. Synthetic velocity fields, as well as a database of PIV measurements of the flow behind the cylinder were the object of the conducted analysis. The synthetic field was generated in the form of homogeneous isotropic turbulence with an analytical field of coherent vortices of two types superimposed on the field, specifically shear vortices with the same vorticity direction and vortex cells with alternating direction of vorticity. The former are typical, for example, for mixing layers, the latter are typical when streamlining bodies. The analysis of the histograms of the generated velocity fields made it possible to associate their peaks with the most probable development phases of the coherent vortex structures. It is shown that with an increase in the level of background turbulence, these peaks blur, while the two-mode velocity histograms are transformed into single-mode ones, which are most often found in turbulent flows. A simple analytical method is proposed for detecting such hidden peaks in single-mode distributions, followed by sampling groups of instantaneous velocity implementations corresponding to the most probable phases of flow development from a common database of random uncorrelated measurements. These groups represent independent data that allow for further analysis, including phase averaging. Along with synthetic velocity fields such phase averaging was used for uncorrelated PIV measurements of 2D fields in the turbulent wake behind the cylinder. It is shown that the proposed phase-by-phase separation of measurement groups from a common database corresponds to the two most probable development phases of the wake behind the cylinder with alternating separation of vortices of different swirls at both sides of the cylinder and their further evolution followed by the formation of a turbulent vortex street.","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 4","pages":"760 - 773"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579493","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

Vortex Structure and Instability Characteristics of Dean–Taylor Flow through a Rotating Bent Square-Shaped Enclosure 旋转弯曲方形外壳中Dean-Taylor流动的涡结构和不稳定特性

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2026-04-01 DOI: 10.1134/S1810232826700013

Rabindra Nath Mondal, Rakesh Bhowmick, Selim Hussen, Giulio Lorenzini

{"title":"Vortex Structure and Instability Characteristics of Dean–Taylor Flow through a Rotating Bent Square-Shaped Enclosure","authors":"Rabindra Nath Mondal, Rakesh Bhowmick, Selim Hussen, Giulio Lorenzini","doi":"10.1134/S1810232826700013","DOIUrl":"10.1134/S1810232826700013","url":null,"abstract":"The present paper investigates solution structure, instability characteristics, and chaotic nature of the Dean–Taylor flow with energy distribution through a rotating bent square-shaped enclosure adopting a spectral-based numerical approach. The channel is rotated about the vertical axis in the positive direction for the Taylor number (0 leqslant {text{Tr}} leqslant 2000). A temperature difference is applied across the vertical walls while a room temperature is maintained on the horizontal walls. Numerical calculations are carried out for the Dean number ({text{Dn}} = 1000) over a wide of curvature ranging from 0.001 to 0.5, and the combined effects of centrifugal, Coriolis, and buoyancy forces are examined. As a result, three branches of asymmetric steady solutions (SS), composed of 2- to 4-vortex solutions, are obtained by using arc-length path continuation technique. To understand the unsteady nature, the transient solution is then inspected by time series analysis, and flow transition is precisely identified by determining the phase trajectory of the temporal development and assessing the power spectrum density. The study shows that, as Tr increases, the flow progresses through various instabilities namely multi-periodic, chaotic, steady-state, periodic, and then chaotic-state again, demonstrating a transition that features asymmetric 2- to 8-vortex solutions. Nusselt numbers are calculated as a measure of convective heat transfer (HT) between the heating wall and the fluid, and it is discovered that chaotic flow (SF) considerably improves convective heat transfer (CHT). Finally, our computational findings are assessed against previously reported experimental data, and an adequate consistency is observed.","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 4","pages":"882 - 912"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579202","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

Heat Transfer and Hydrodynamics during Condensation of Stagnant Vapor on Horizontal Finned-Tube Bundles: A Brief Review 水平翅片管束凝结水的传热与流体力学研究进展

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2026-04-01 DOI: 10.1134/S1810232825700237

I. I. Gogonin, O. A. Volodin

引用次数: 0

Hydrodynamics of the Oil–Water Mixture Flow in a Pipeline 管道中油水混合物流动的流体力学

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-11-02 DOI: 10.1134/S1810232825700018

E. M. Abbasov

引用次数: 0

Environmental Performance Study of R410A Alternative-R446A, R447B, and R459A for Space Heating Application R410A - r446a、R447B和R459A在空间采暖中的环境性能研究

IF 1.4 4区工程技术

Journal of Engineering Thermophysics Pub Date : 2025-11-02 DOI: 10.1134/S1810232825700043

Jinxiu Zhao, Liu Zhang, Na Pei, Lina Mu

{"title":"Environmental Performance Study of R410A Alternative-R446A, R447B, and R459A for Space Heating Application","authors":"Jinxiu Zhao, Liu Zhang, Na Pei, Lina Mu","doi":"10.1134/S1810232825700043","DOIUrl":"10.1134/S1810232825700043","url":null,"abstract":"Facing the challenges of climate change and global warming, the engineering community is paying more attention to the carbon emission reduction for building sector. In this study, various heat supply forms including air source heat pump with R410A or R410A alternatives (R32, R446A, R447B, and R459A), electric heater, gas-fired water heater are evaluated for carbon emissions for environmental performance. All R410A alternatives have a higher COP than R410A. R446A displays the highest COP while R32 the second. R32 showed a higher heating capacity, and R410A also displays a higher capacity than its other alternatives except R32. The carbon emission contributed by the electrical heater is more than 3.5 times than that by the air source heat pump heat supply form. The gas-fired water heater produces ~2.2 times for the value of the carbon emission from the heat pump unit. For air source heat pump emission distribution, the sector of the energy consumption shares the largest, more than 90% share, followed by the sector of the annual refrigerant leakage. R446A unit has a value of 18% carbon emission reduction, and R447B and R459A unit hold an emission reduction value of 13.5 and 12% from R410A heat pump. The annual refrigerant leakage takes up ~6% of the R410A unit total emissions; it only takes less than 3% of the unit total emissions for the unit of R410A alternatives. All air source heat pump unit display a lower total emission value when the COP has been improved. In general, Chengdu displays the lowest emission while Beijing is highest due to the difference for climate conditions.","PeriodicalId":627,"journal":{"name":"Journal of Engineering Thermophysics","volume":"34 3","pages":"601 - 612"},"PeriodicalIF":1.4,"publicationDate":"2025-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145420601","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