International Journal of Heat and Mass Transfer最新文献

{"title":"Generalized physics-based cavitation model encompassing multiple cavitation regimes","authors":"Lester Toledo ,&nbsp;Kyungjun Choi ,&nbsp;Hyunji Kim ,&nbsp;Chongam Kim","doi":"10.1016/j.ijheatmasstransfer.2025.126898","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126898","url":null,"abstract":"<div><div>Accurate modeling of multiple cavitation regimes and their thermodynamic effects remains a challenge. This study extends the baseline physics-based cavitation model to a generalized form, encompassing the inertial, intermediate, and thermal cavitation regimes including the extreme thermal regime at very low Jakob number. For this purpose, a single bubble growth rate that is valid over a broad range of Jakob number is formulated. The dynamics of intermediate regime is captured by employing local pressure and temperature conditions. Key physical corrections for the bubble growth initiation, time delay, and growth acceleration are taken into account. The proposed cavitation model is then carefully validated and critically assessed with a series of test cases including homogeneous bubble growth over multiple cavitation regimes, cryogenic and isothermal cavitating flows. The bubble growth tests confirm its superior performance, particularly in the intermediate regime, and yield an excellent agreement with the experimental bubble growth curve over the entire bubble growth regime. Other computed results also show accurate capturing of cavitation features and thermal effects, demonstrating its utility in a wide range of operation conditions. Especially, the physical mechanism of multiple bubble pulsations is unveiled by analyzing the contribution of bubble growth rate from each cavitation regime.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126898"},"PeriodicalIF":5.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641725","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":"Effect of thermophysical properties of perovskite electrolytes on intermediate temperature SOFC","authors":"Baitong Wang,&nbsp;Mingshang Liu,&nbsp;Zide Wu,&nbsp;Xun Liu,&nbsp;Mu Li,&nbsp;Dawei Tang","doi":"10.1016/j.ijheatmasstransfer.2025.126944","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126944","url":null,"abstract":"<div><div>Solid oxide fuel cell (SOFC) has captured significant interest and the electrolyte material is the key during operating. The present work introduces a series of intermediate temperature perovskite materials regarding of synthesis and characterization method. Corresponding thermophysical properties including thermal diffusivity, specific heat and thermal conductivity were determined at relevant temperature range. The result shows that thermal diffusivity has a stable tendency for the intermediate temperature electrolytes materials; Ba₃NbMoO_8.5 has the highest specific heat and BaSc_0.8MoNb_0.2O_2.8 has the highest thermal conductivity at 873 K. Besides, a 3-D model is established including transient state and steady state. After combining intermediate temperature electrolyte materials with different thermophysical properties, it is found that the maximum temperature gradient and thermal shock exist at switching time (<em>t</em> = 600 s) and the tendency are controversial for each other. Besides, after comparing different supported structure of SOFC, a systematic selection strategy is provided for IT-SOFC application. Cathode-supported structure SOFC is an ideal choice for long term usage, which has a low temperature gradient; whereas electrolyte-supported structure with Na_0.5Bi_0.5TiO₃ electrolyte is beneficial to quick start-up system, which has the lowest thermal shock.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126944"},"PeriodicalIF":5.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143686832","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":"Corrigendum to \"Pressure dependence of controlling parameters for heat-mass transfer in buoyant-flow aided upward flame spread over vertical electrical wire\" [Int. J. Heat Mass Transf. 240 (2025) 126653]","authors":"Yuxuan Ma ,&nbsp;Jiang Lv ,&nbsp;Zhengda Guo ,&nbsp;Yan Gu ,&nbsp;Yajun Huang ,&nbsp;Xiaolei Zhang ,&nbsp;Longhua Hu","doi":"10.1016/j.ijheatmasstransfer.2025.126916","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126916","url":null,"abstract":"","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126916"},"PeriodicalIF":5.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704112","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":"Correlation for wall-temperature oscillations in unsteady stagnation point convective heating","authors":"Tobias Hermann","doi":"10.1016/j.ijheatmasstransfer.2025.126907","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126907","url":null,"abstract":"<div><div>The purpose of this paper is to provide insight into how unsteady flow temperature affects the wall temperature of test articles exposed to convective heating. To this end, a simplified analytical correlation is derived that allows the determination of wall temperature fluctuation amplitude in the case of an unsteady freestream. Stagnation point flows with oscillating freestream temperature are analysed applying self-similar boundary layer theory. The correlation reveals that the problem is fully described by two non-dimensional parameters: the ratio of fluid and solid thermal effusivities, and the ratio <span><math><mrow><msqrt><mrow><mi>Sr</mi><mspace></mspace><mi>Pr</mi><mspace></mspace><mi>Re</mi></mrow></msqrt><mo>/</mo><mi>Nu</mi></mrow></math></span> of Strouhal, Prandtl, Reynolds, and Nusselt numbers. Numerical conjugate heat transfer simulations are performed for a solid test article subjected to convective heating. The derived analytical correlation agrees well with simulation results, spanning ten orders of magnitude in wall-to-freestream temperature amplitude ratio, with maximum discrepancies of 35%. Deviations from theory occur for low frequencies where the wall temperature of the solid medium undergoes significant temperature changes. Experimental measurements of an unsteady plasma freestream are analysed, predicting wall-temperature fluctuations of test articles of different sizes. High frequency content is shown to have little influence, while low frequencies contribute most to wall temperature fluctuations. Small sample sizes are shown to suffer from much larger wall-temperature fluctuation amplitudes, and high-density flow conditions are more severely affected. The derived theory can be applied to aid in both design and analysis of unsteady convective heating experiments.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126907"},"PeriodicalIF":5.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143686833","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":"Experimental study of the condensing heat transfer characteristics in a circular tube bank fin air cooler and the comparison to a flat tube bank fin air cooler","authors":"Shi-Qiang Zhu ,&nbsp;Liang-Bi Wang ,&nbsp;Xin Na ,&nbsp;Zhi-Min Lin ,&nbsp;Xiao-E Zhang","doi":"10.1016/j.ijheatmasstransfer.2025.126974","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126974","url":null,"abstract":"<div><div>The direct air-cooling technology employed in power plants offers significant potential for conserving water resource. The condensing heat transfer characteristics in the tubes of air cooler are crucial, and such condensation is enforced by air flow. Now most air-cooling islands of power plant use finned flat tube instead of finned circular tube or circular tube bank fin air cooler (CTBFAC) to decrease the air flow pressure drop. This paper performs an experimental study of the condensing heat transfer characteristics in a CTBFAC. The condensing heat transfer characteristics of the CTBFAC are compared to that of the flat tube bank fin air cooler (FTBFAC). The main experimental results demonstrate that: air flow rate plays a vital role in condensation heat transfer, there are strong coupling correlations between the tube side liquid/steam Reynolds number (<em>Re</em>_LS/<em>Re</em>_s), Nusselt number (<em>Nu</em>_s) and the air side Reynolds number (<em>Re</em>_a): <em>Re</em>_LS = 0.748<em>Re</em>_a^0.759 (1−<em>β</em>/180)^−0.169, <em>Re</em>_s = 12.704<em>Re_a</em>^0.760 (1−<em>β</em>/180)^−0.162, <em>Nu</em>_s = 1.510<em>Re</em>_a^0.455 (1−<em>β</em>/180)^−0.216, within the range of <em>Re</em>_a from 295 to 1100 and the range of inclination angle (<em>β</em>) from 30° to 90°. At the same <em>Re</em>_LS/<em>Re</em>_s, <em>Nu</em>_s of the CTBFAC is significantly higher than that of the FTBFAC.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126974"},"PeriodicalIF":5.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636572","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 analyses of flow boiling heat transfer on downward-facing surface at low inclination: Critical heat flux and vapor bubble dynamics","authors":"Min Suk Lee ,&nbsp;Hyoung Suk Yu ,&nbsp;Jun Yeong Jung ,&nbsp;Dong Hoon Kam ,&nbsp;Yong Hoon Jeong","doi":"10.1016/j.ijheatmasstransfer.2025.126960","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126960","url":null,"abstract":"<div><div>Numerous studies on critical heat flux (CHF) on a downward-facing heating surface in a low inclination channel have been reported, yet a profound understanding of CHF is still lacking under these conditions, which reflect the optimized design of thermal systems with a large surface that manage a large amount of heat. Flow boiling experiments were conducted in this work to evaluate boiling heat transfer and CHF with a downward-facing heating surface and very low inclination (10°) flow channel. The experimental conditions in this study were determined from the configuration of the core catcher as a representative system utilizing the flow boiling phenomenon on a 10° inclined large heating surface. Mass flux and subcooling effects on boiling heat transfer and CHF were evaluated, and analyses were performed on the heater and fluid temperature measurement results. Furthermore, an optical probe with two fiber sensor tips and a high-speed camera were used to estimate the vapor bubble characteristics. Results indicate that CHF increases with increasing mass flux and subcooling, while other distinct phenomena were observed including an overheated fluid region around the heater surface, condensation-induced water hammer events under 15 K subcooling, and converged local void fraction near the CHF.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126960"},"PeriodicalIF":5.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636571","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 conduction optimized heat sinks with enhanced fluid flow path for passive cooling applications","authors":"Huanyu Zhao ,&nbsp;Hanyang Ye ,&nbsp;Huaxu Liang ,&nbsp;Pengfei Liu ,&nbsp;Yugo Asai ,&nbsp;Hideaki Miyamoto ,&nbsp;Ryo Kajitani ,&nbsp;Tsutomu Sakata ,&nbsp;Jin Yao Ho","doi":"10.1016/j.ijheatmasstransfer.2025.126963","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126963","url":null,"abstract":"<div><div>Passive cooling, which utilizes natural convection and thermal radiation as the heat removal mechanisms, offers the advantages of high reliability, compactness, noise-free and low-energy-cost for thermal management of electronics. Unfortunately, existing passive heat sinks have limited geometrical variation to take advantage of the heat dissipation mechanisms, leading to large air flow paths and conduction resistances. To overcome these shortcomings of conventional passive heat sink designs, this study proposes three categories of passive heat sinks including parameter optimized cross-shaped plate fins (CF), topology optimized tree-shaped fins (TF) and hybridized cross-shaped and tree-shaped fins (CF-TF). While the CF heat sinks aim to reduce the air flow resistance to increase the average air velocity in the heat sinks and the TF heat sinks simultaneously reduce the fin conduction resistance and increase the wetted area for enhanced heat transfer, the CF-TF heat sinks synergize the advantages of both CF and TO topology to further enhance cooling performance. Using selective laser melting (SLM), a laser powder bed fusion (LPBF) process, we showed that the complex geometries of the heat sinks can be readily fabricated with short production time and at low cost, thus demonstrating the potential of utilizing LPBF for full scale production for these heat sinks. Furthermore, using Fourier transform infrared spectroscopy (FTIR), we showed that the SLM-fabricated heat sinks made from AlSi10Mg have the added advantage of significantly higher spectral emissivity, thus enhancing radiation heat dissipation as compared to conventionally casted aluminum alloy, Al6061. To evaluate the passive cooling performance of the new heat sinks, they were experimentally characterized in an environmental chamber. Our results showed that the best hybridized heat sink (CF0-TF16), cross-shaped heat sink (CF2), and topology optimized heat sink (TF16-R) exhibited 10.6 % 10.5 % and 10.0 % reduction in thermal resistance as compared to the best conventional plate fin heat sink, respectively. More importantly, the thermal enhancements of CF0-TF16, CF2 and TF16-R were achieved at the weight reductions of 14.8 %, 18.7 % and 20.7 %, respectively, as compared to the conventional heat sink. This research demonstrates the advantage of synergizing new thermal design strategy and additive manufacturing technique to develop passive cooling devices with simultaneous thermal efficiency enhancement and weight reduction.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126963"},"PeriodicalIF":5.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636449","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":"Onset of liquid films instability in microchannel flow boiling","authors":"Adam Kriz,&nbsp;Saeed Moghaddam","doi":"10.1016/j.ijheatmasstransfer.2025.126964","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126964","url":null,"abstract":"<div><div>Microchannel flow boiling is becoming increasingly important in many applications, yet its modeling has remained a challenge due to a lack of mechanistic fluid flow models, particularly for thin liquid films. In a recent study, we determined the liquid film thickness and velocity in 300-µm-wide microchannels and used the results to calculate the shear stress at the liquid-vapor interface. A graph of the shear stress versus the liquid film thickness delineated transition to wavy-annular flow regime. Here, we have extended our studies to different channel sizes and fluids, from low to high surface tension, using a combination of flow boiling and adiabatic test studies. The results show that the onset of films instability is a function of the shear stress at the liquid-vapor interface, consistent with the Kelvin-Helmholtz (K-H) instability. Various criteria for the onset of K-H instability are evaluated. The Richardson number (<em>Ri</em>) as an indicator of the onset of film instability is shown to decrease greatly for thin films in microchannels and is demonstrated to be dependent on surface tension such that Bond number, <em>Bo</em>/<em>Ri</em> for different fluids are relatively close. However, this criterion does not accurately predict the onset of instability of relatively thinner films. Further analysis suggests that Taitel and Dukler's (1976) criterion can accurately predict instability of adiabatic films. However, liquid films in boiling become unstable at a significantly lower interfacial shear stresses relative to Taitel and Dukler's prediction. Additional forces and perturbation mechanisms such as evaporative momentum effects, acoustics of nucleate boiling, and local temperature-induced surface tension variations could account for deviations relative to adiabatic films.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126964"},"PeriodicalIF":5.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636453","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":"Enhancing pool boiling with separated liquid-vapor pathways on perforated micromesh surface","authors":"Yuxuan Chen ,&nbsp;Pengkun Li ,&nbsp;Qifan Zou ,&nbsp;Xiuliang Liu ,&nbsp;Ronggui Yang","doi":"10.1016/j.ijheatmasstransfer.2025.126949","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126949","url":null,"abstract":"<div><div>Boiling heat transfer has been utilized in many industrial applications, including thermal power plants, air conditioners, and thermal management of electronics and data centers. Micro/nano-structured surfaces have been developed to enhance the key performance metrics of boiling, including heat transfer coefficient (HTC) and critical heat flux (CHF). Porous structures, such as sintered micromesh and packed micropowders, show great promise in promoting bubble nucleation. However, the conflicting requirements of HTC and CHF for surface structures make it challenging to simultaneously enhance both CHF and HTC on porous surfaces. In this work, stacked micromesh surfaces are perforated to enhance bubble nucleation, and facilitate bubble escape and liquid delivery through separated liquid and vapor pathways. Nucleated bubbles within the micromesh pores can easily escape through perforations due to low flow resistance, significantly augmenting HTC. Liquid supply is improved due to decreased obstruction of vapor bubbles in liquid pathways, leading to enhancement of CHF. Both visualization of bubble dynamics and theoretical analysis of liquid-vapor transport are conducted to demonstrate the effectiveness of perforation design for the separation of liquid and vapor transport. Significant enhancements are demonstrated on the perforated micromesh surface with a perforation spacing of 2 mm compared to a smooth copper surface, with HTC and CHF increasing by 598 % and 136 %, respectively.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126949"},"PeriodicalIF":5.0,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632007","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 generalized performance evaluation plot for flow resistance reduction design of heat transfer surfaces","authors":"Wanlong Jin,&nbsp;Limin Wang,&nbsp;Lei Deng,&nbsp;Gaofeng Fan,&nbsp;Defu Che","doi":"10.1016/j.ijheatmasstransfer.2025.126941","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126941","url":null,"abstract":"<div><div>The performance evaluation plot (PEP) is a visualized performance evaluation method with definite physical meaning. However, the strict constraints including property constraints, geometry constraints and operation constraints restrict the generality of PEP. The previous PEPs are oriented for heat transfer enhancement technologies. In this study, the constraints restricting the applicability of PEP are removed, and a generalized PEP for flow resistance reduction design of heat transfer surfaces is proposed. The multiple evaluation criteria including power consumption comparison under heat duty constraint, pressure drop comparison under heat duty constraint and comparison of Fanning friction factor over heat transfer rate under equal mass flow rate can be performed in the same plot. The effectivity of flow resistance reduction design can be easily determined by the position comparisons between working lines and baselines. Three intercept factors based on the developed PEP are proposed for quantitative evaluation. The accuracy and applicability of the proposed evaluation method are verified. It is reliable and practicable for evaluating the comprehensive hydraulic performance of heat transfer surfaces. The comprehensive performance comparison of printed circuit heat exchangers with rectangular and airfoil fins is presented to illustrate the application of generalized PEP.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126941"},"PeriodicalIF":5.0,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143628017","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}