International Journal of Heat and Mass Transfer最新文献

{"title":"Mass transport characteristic of radial gradient porous scaffolds manufactured by selective laser melting","authors":"Jiping Zhu ,&nbsp;Bibo Yao ,&nbsp;Zhenhua Li ,&nbsp;Meihong Liu ,&nbsp;Zixi Zhang ,&nbsp;Yongchang Qi ,&nbsp;Tao Wen","doi":"10.1016/j.ijheatmasstransfer.2024.126320","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126320","url":null,"abstract":"<div><div>Permeability, a critical factor that characterizes the mass transfer efficiency of bone scaffolds, significantly influences the material exchange process following the implantation of the scaffold and the extent of restoration of injured bone tissue. In this study, radial gradient scaffolds were designed using Triply Periodic Minimal Surface(TPMS) Gyroid structure with a consistent porosity of 50% and fabricated by Selective Laser Melting (SLM) technology. The permeability performance of the scaffolds was assessed using a combination of experimental methods and Computational Fluid Dynamics (CFD) simulations. The results indicate that with the increase of gradient value, the pore size in the vicinity of the scaffolds' center expands, thereby improving fluid transport capability. The permeability of gradient scaffolds increases by approximately 8.65% to 44.2% in comparison to that of the uniform scaffold, and the permeability of all scaffolds (1.04 - 1.50×10⁻⁹ m²) meets that the demand of human trabecular bone. The variations in permeability of each scaffold in various experimental settings result from the change of fluid flow states at the microscale level. In addition, the CFD analysis results of the scaffold microchannel indicate that surface roughness significantly affects fluid flow behavior and distribution within the scaffold pores, resulting in the difference between experimental and simulation results. The design methodology suggested in this research decouples the porosity and permeability, providing valuable insights for optimizing the performance of bone scaffolds.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126320"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Near-field radiative heat transfer between metaterminals composed of SiC plate-supported LiH nanoparticle arrays","authors":"Cunhai Wang ,&nbsp;Hao Bian ,&nbsp;Dewei Fan ,&nbsp;Pengfei Zhang ,&nbsp;Jingchong Liu","doi":"10.1016/j.ijheatmasstransfer.2024.126375","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126375","url":null,"abstract":"<div><div>Near-field radiative heat transfer (NFRHT) can break through the blackbody limit by several orders of magnitude, bringing great thermal management opportunities. However, regulating the intensity NFRTH at a fixed terminal gap is still challenging. In this work, we theoretically investigate the NFRHT between two metaterminals separated by a vacuum gap using the dipolar model. Each metaterminal comprises a silicon carbide (SiC) substrate covered by periodic lithium hydride (LiH) nanoparticle arrays. We demonstrate that the surface and hyperbolic modes excited by the hybrid LiH/SiC metasurface can regulate the radiative heat flux between the two terminals. Effects of the radius of the LiH particle (<em>r</em>), the lattice constant of the particle arrays, and their ratio on NFRHT and the underlying regulation mechanisms are revealed. Results indicate that at a fixed vacuum gap of 100 nm, the total flux between the LiH/SiC metaterminals can be increased from weaker (0.69 × 10⁴ W/m²) to stronger (2.79 × 10⁴ W/m²) than that (1.33 × 10⁴ W/m²) between SiC planar terminals when the particle radius increases from <em>r</em> = 25 to 75 nm. The physical mechanism of NFRHT modulation is revealed through the effective dielectric function and energy transmission coefficients in different scenarios. This work provides a controllable means for manipulating NFRHT between terminals at a fixed gap size.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126375"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reinterpreting the segregation potential model for frozen soils","authors":"Xiao-kang Li ,&nbsp;Xiang-sheng Chen ,&nbsp;Xu Li","doi":"10.1016/j.ijheatmasstransfer.2024.126337","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126337","url":null,"abstract":"<div><div>For the past half-century, the segregation potential (SP) model has been extensively employed for characterizing heat and water transfer during soil freezing. However, the relation of SP with temperature and its applicability in unsaturated soils remains unclear, restricting the application scope of SP model to the thermal steady state of saturated frozen soil. To address the aforementioned issues, this study first reinterprets the classical SP model using thermodynamics, yielding the general SP function <em>G</em>(<em>T</em>). After that, the dynamic <em>G</em>(<em>T</em>) model is proposed for saturated-unsaturated soils. Moreover, by adopting the proposed <em>G</em>(<em>T</em>) function, the steady thermal profile of freezing soil column is analytically solved. Finally, an extended SP model is proposed based on the aforementioned insights. The main findings were as follows. (1) The newly introduced <em>G</em>(<em>T</em>) function extends the classical SP into a continuous function with temperature, which can be transformed from the hydraulic conductivity function of frozen soils. The classical SP parameter is essentially an average value of <em>G</em>(<em>T</em>) among frozen fringe. (2) The proposed dynamic <em>G</em>(<em>T</em>) model can uniformly express <em>G</em>(<em>T</em>) curves amidst varying degrees of saturation. (3) At the stable freezing state, the temperature profile is analytically nonlinear in the frozen fringe. (4) The extended SP model refines the governing equations and applicable scenarios of SP model, bringing new understandings regarding soil freezing and ice segregation process. In summary, this study not only clarifies the ambiguities but also strengthens the theoretical foundation and mathematical expression of the SP model.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126337"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a numerical model for frost formation on ultra-low temperature surfaces considering both desublimation and fog deposition","authors":"Akihiro Hattori ,&nbsp;Tetsuya Sato ,&nbsp;Takehiro Himeno ,&nbsp;Toshinori Watanabe","doi":"10.1016/j.ijheatmasstransfer.2024.126321","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126321","url":null,"abstract":"<div><div>Liquified hydrogen, which is expected to be a next-generation, environmentally friendly energy source, can be used as a cryogenic refrigerant. A cryogenic precooler (a heat exchanger between air and liquified hydrogen) has been developed for the hypersonic engine in the aerospace field. It cools the incoming air compressed at the engine's air intake using liquified hydrogen (cryogenic fuel) as a refrigerant to save the core engine from heat load and improve efficiency. However, frost formation in a precooler is a severe issue. In the present study, we developed a valid numerical method for predicting frost formation on cryogenic temperature surfaces to avoid frosting problems. The feature of the present model is considering the frost growth due to fog deposition, which has not been considered in the previous models, in addition to desublimation and fog formation. We conducted verification analyses for the frosting under forced convection on a flat cold plate at −170 °C. On an ultra-low temperature plate (−170 °C), the characteristic phenomena, including frost layer separation, were reproduced, and the frost mass and height were in quantitative agreement with the experimental data. The numerical results clarified the water vapor consumption due to fog formation and the contribution of desublimation and fog deposition to frost growth. Desublimation was dominant at the front end. On the rear side, fog formation was initially significant, and its deposition was dominant. Desublimation was suppressed because fog formation consumed water vapor. After that, the dominant mechanism gradually changed from fog deposition to desublimation because fog formation was gradually suppressed with time. These results were consistent with the experimental observation. Moreover, we also confirmed the validity of the present model for frosting on a plate of −75 °C, in which the influence of fog formation and deposition differed from at −170 °C. The model developed in this research can simulate frost formation on various temperature surfaces, from general-low temperatures where only desublimation is dominant to ultra-low temperatures where fog formation and deposition have significant impacts.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126321"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Thermal investigations of supercritical CO2 jet impingement and its cooling applicability in a machining context","authors":"P. Masson ,&nbsp;M. El Nahas ,&nbsp;T. Pottier ,&nbsp;J.-J. Letourneau ,&nbsp;M. Sauceau ,&nbsp;Y. Landon","doi":"10.1016/j.ijheatmasstransfer.2024.126335","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126335","url":null,"abstract":"<div><div>In recent years, the use of supercritical carbon dioxide (sCO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>) as cutting fluid during machining operations has gained attention of the manufacturing community. The present paper intends to address thermal characteristics of sCO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> free jet impingement on a hot plate. An experimental approach has been hereby chosen in order to assess the heat transfer coefficient (HTC) in various experimental conditions. Infrared thermography along with high speed imaging are set up in order to access the cooling of a titanium plate. HTC is then calculated from an analytical solution of the heat transfer equation adapted to the specific conditions of the proposed setup. Investigations are focused on the influence of nozzle-to-plate distance (from 4 to 106 times jet diameter), angle of incidence (from <span><math><mrow><mn>90</mn><mstyle><mo>°</mo></mstyle></mrow></math></span> to <span><math><mrow><mn>50</mn><mstyle><mo>°</mo></mstyle></mrow></math></span>) and flow initial temperature (40<!--> <!-->°C to 80<!--> <!-->°C) and pressure (<span><math><mrow><mn>100</mn><mspace></mspace><mstyle><mi>b</mi><mi>a</mi><mi>r</mi></mstyle></mrow></math></span> to <span><math><mrow><mn>285</mn><mspace></mspace><mstyle><mi>b</mi><mi>a</mi><mi>r</mi></mstyle></mrow></math></span>). Results provide with metric and dimensionless values of the HTC. Preliminary conclusions are drawn from the presence of solid carbon dioxide at the plate’s surface and leads are proposed to investigate in further detail the effect of the jet nature and structure on its cooling ability.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126335"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A review of scraped surface heat exchangers: Parameters describing thermal-fluid processes, influence of their internal geometric parameters and energy consumption","authors":"Kamil Kowalski,&nbsp;Przemysław Błasiak,&nbsp;Sławomir Pietrowicz","doi":"10.1016/j.ijheatmasstransfer.2024.126336","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126336","url":null,"abstract":"<div><div>The Scraped Surface Heat Exchanger (SSHE) is widely used across various industries because of its efficiency in providing thermal treatment of viscous fluids. This article presents a detailed analysis of SSHEs, emphasizing both existing solutions and areas that require further research and development. The literature review was conducted by organizing content related to SSHEs into sections focused on thermal-flow topics, energy consumption, and geometric solutions. The review of thermal-flow processes includes information on correlations for the Nusselt number, along with presenting them on a summary chart. The thermal flow issue was also expanded to include the classification of fluids, along with discussions of modified definitions for the Rotational Reynolds number and Taylor number. A fluid classification map was also created, intended to serve as a new tool to support research. The discussion on energy consumption focuses on a summary chart illustrating the relationship between the Power number and the Rotational Reynolds number. Various blade geometries and their impact on SSHE performance are reviewed. The analysis reveals gaps showing low accuracy in thermal-flow and energy consumption calculations. Therefore, it is proposed that future research should focus on developing a universal correlation of the Nusselt number and determining the conditions for flow regime changes. It also emphasizes the importance of the shape of the blade in an SSHE design. In addition, it is suggested that improved measurement accuracy could help with energy demand estimation. The use of advanced technologies such as particle image velocimetry is recommended to enhance the quality of future experimental studies.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126336"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-Newtonian melting dynamics and magneto-convective modes of nano-enhanced phase change materials driven by thermocapillary convection under microgravity","authors":"Yijie Zhuang ,&nbsp;Zihao Huang ,&nbsp;Jing-Chun Feng","doi":"10.1016/j.ijheatmasstransfer.2024.126284","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126284","url":null,"abstract":"<div><div>In this work, a novel numerical model is proposed to analyze the phase change heat transfer characteristics and magneto-convective mode distributions of composite phase change materials under the thermocapillary effect. The model describes thermocapillary convection and magneto-convection through shear stress boundary conditions and Kelvin force source terms, respectively, and combines the enthalpy-porosity method, Darcy-Forchheimer law, local thermal non-equilibrium model, and non-Newtonian power law model for detailed simulations. The melting dynamics under the influence of different nanoparticle mass fractions (<span><math><msub><mstyle><mi>Φ</mi></mstyle><mrow><mi>w</mi><mi>t</mi></mrow></msub></math></span>), magnetic numbers (Mn) and Marangoni numbers (Ma) are revealed. The results show that Fe₃O₄ nanoparticles have a positive effect on the melting process at different Ma. It not only accelerates the advance of the heat conduction region, but its induced shear-thinning characteristics also improve the melting in the upper part of the cavity. At Ma = 5 × 10⁴, the thermal storage efficiency of 5 wt% NEPCM is improved by 14.1 % over pure PCM. There is a competition between magneto-convection and thermocapillary convection, so that different Ma and Mn cause the magnetic field to exhibit either a facilitating or inhibiting effect. At Ma = 5 × 10⁴, compared to the case without a magnetic field, the total melting time increased by 6 %, 0.4 % and decreased by 3.4 % for Mn = 2 × 10⁶, 5 × 10⁶ and 8 × 10⁶, respectively. In the range of low Ma, the oscillatory magneto-convection induced by high magnetic field strength can be divided into three phases. In the second stage, a periodic six-vortex circulation structure occurs in the magneto-convective region. The formation mechanism is that the magnetic field force drives the fluid on the lower left side to continuously form vortices in different directions, thus driving the whole circulation structure to achieve periodic evolution.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126284"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigation on flow boiling heat transfer of fuel cladding with chalk river unidentified deposits","authors":"Zhiping Hu ,&nbsp;Jiejin Cai ,&nbsp;Rining Deng","doi":"10.1016/j.ijheatmasstransfer.2024.126371","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126371","url":null,"abstract":"<div><div>The flow boiling visualization experiment is conducted to simulate the actual fuel rod cladding with Chalk River Unidentified Deposits (CRUD) by using layer-by-layer deposition of SiO₂, under two mass flow rates (0.12 m s^-1, 0.17 m s^-1) and three degrees of subcooled conditions (0 K, 3 K, 5 K), investigating the flow boiling heat transfer characteristics of fuel cladding Zr-4 alloys non-deposition with two Zr-4 alloys SiO₂ deposition (1 <span><math><mrow><mi>μ</mi><mi>m</mi></mrow></math></span>, 3 <span><math><mrow><mi>μ</mi><mi>m</mi></mrow></math></span>). Focus on the variation of heat flux <em>q''</em> and active nucleation site density (NSD) <em>Na</em>, bubble departure frequency (BDF) and bubble departure diameter (BDD) <em>Dd</em> with wall superheat, and analyze the main reasons for the differences under different operating conditions. The BDD is also compared with existing predicti<em>v</em>e models. The results show that the deposited Zr-4 alloys has a higher flow heat transfer capacity and can achieve higher values of critical heat flux (CHF) than the undeposited Zr-4 alloys, and this difference is mainly caused to the difference in surfaces porosity. The 3<span><math><mrow><mi>μ</mi><mi>m</mi></mrow></math></span> SiO₂ deposited Zr-4 alloysis most obvious, and the CHF is enhanced to 118.99 % at the flow rate of 0.12 m s^-1 and subcooled of 0 K. For the same experimental samples, the larger the subcooled and flow rate, the more obvious the trend of heat flux growth with the increase of wall superheat, the higher <em>Na</em> of the deposited Zr-4 alloys than that of the undeposited Zr-4, and the largest <em>Na</em> of 3<span><math><mrow><mi>μ</mi><mi>m</mi></mrow></math></span> SiO₂ at the flow rate of 0.12 m s^-1 and subcooled of 0 K. Compared with the undeposited Zr-4 alloys, BDF and <em>Dd</em> are larger for the deposited Zr-4 alloys, and the BDF and <em>Dd</em> are smaller for the larger subcooled degree. An improved prediction equation for <em>Dd</em> is proposed under the condition of CRUD layer, and the error band between the predicted and experimental values of the new prediction equation is &lt;30 %. The deviation between the predicted and actual values for the 3 <span><math><mrow><mi>μ</mi><mi>m</mi></mrow></math></span> deposition surfaces is less than ±10 %.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126371"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Splash characteristics and mechanics upon drop impingement on a low-temperature surface","authors":"Yi Liu,&nbsp;Na Liang,&nbsp;Jilin Lei,&nbsp;Shiquan Shen,&nbsp;Yao Gou","doi":"10.1016/j.ijheatmasstransfer.2024.126356","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126356","url":null,"abstract":"<div><div>The process of drop impingement on low-temperature surface is considerably different from that on surface at room temperature or high-temperatures, particularly when the drop has a high incident velocity. In this study, the characteristics of the corona structure and the splashing process of n-dodecane drops on a smooth aluminum surface, whose minimum temperature reaches up to 233 K, were investigated. The maximum width, height, and duration of the corona increase significantly for a surface at lower temperature, and the number and diameter of the secondary droplets increase significantly after splashing. Splashing becomes easier on low-temperature surfaces owing to the cooling effect of the low-temperature surface. The Weber number required for splashing reduces from 400 to 250 as the surface temperature decreases from 293 K to 233 K. A splashing threshold model given by <span><math><mrow><msub><mi>P</mi><mi>c</mi></msub><msubsup><mi>T</mi><mi>c</mi><mrow><mo>−</mo><mn>0.5</mn></mrow></msubsup><mi>W</mi><msub><mi>e</mi><mi>T</mi></msub><mo>=</mo><mn>6.5</mn><mi>R</mi><msubsup><mi>e</mi><mi>T</mi><mrow><mn>0.5</mn><mspace></mspace></mrow></msubsup><mo>,</mo><mspace></mspace></mrow></math></span>which considers the cooling effect of the surface, liquid properties, and gaseous forces, was formulated.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126356"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of initial cooling process on frosting characteristics of a cryogenic surface under different water vapor content conditions","authors":"Hengyang Ye ,&nbsp;Wenhan Shu ,&nbsp;Yinghe Qi ,&nbsp;Song Fang ,&nbsp;Shaolong Zhu ,&nbsp;Hanying jiang ,&nbsp;Xiaoqin Zhi ,&nbsp;Limin Qiu ,&nbsp;Kai Wang","doi":"10.1016/j.ijheatmasstransfer.2024.126355","DOIUrl":"10.1016/j.ijheatmasstransfer.2024.126355","url":null,"abstract":"<div><div>Widespread frosting typically leads to negative effects. Elucidating the mechanisms and characteristics of frosting is essential for developing effective frost control technologies. Practical applications usually include a cooling process, but the impact of the initial cooling process on the frosting characteristics of a cryogenic surface under different water vapor content conditions is scarcely reported. Utilizing a cryogenic visualization experimental setup, the impact of the initial cooling process on frosting characteristics with different water vapor content (60–1200 ppmv) was studied. Without an initial cooling (i.e., cryogenic surface with a fixed temperature around 120 K), the impact of water vapor content on the frosting process is relatively minor due to the same frosting mechanism. In contrast, with an initial cooling (i.e., surface temperature decreasing from 293 to 120 K), different water vapor content conditions may bring significantly different frost crystal morphology and thickness due to the transition in frosting mechanisms. Therefore, different water vapor content conditions exhibit different sensitivities to the initial cooling process. As for 60 ppmv, the average frost surface height and roughness after frosting 120 min with initial cooling are only 1.1 and 1.1 times those without initial cooling. However, when increasing to 1200 ppmv, these values after frosting 30 min significantly increase to 11.5 and 37.8 times, respectively. This study provides valuable insights into understanding frosting mechanisms and characteristics under different condition.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"236 ","pages":"Article 126355"},"PeriodicalIF":5.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}