International Journal of Heat and Mass Transfer最新文献

{"title":"Constrained Large Eddy Simulation for incompressible wall-bounded turbulence with passive scalar field","authors":"Yanchen Liu ,&nbsp;Yantao Yang ,&nbsp;Yipeng Shi ,&nbsp;Shiyi Chen","doi":"10.1016/j.ijheatmasstransfer.2025.126892","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126892","url":null,"abstract":"<div><div>Transfer of passive scalars, such as heat and mass, by turbulence is a crucial process in many natural and engineering applications, and accurately modeling of such processes is of great importance. In this work we present a new method of large-eddy simulation (LES) for wall-bounded turbulence with passive scalar. Specifically, we extend the so-called constrained-LES (CLES) of wall-bounded turbulence to the scalar turbulence. CLES was first developed by Chen et al. (2012) to successfully resolve the mismatch problem of mean velocity profiles in detached-eddy simulations. Following the same methodology, here the scalar field is solved by using LES over the whole domain. A Reynolds averaged Navier–Stokes (RANS)-type of turbulent scalar flux is imposed onto the subgrid stress only within an inner layer adjacent to the wall boundary. Specifically, we utilize an eddy diffusivity model for the RANS turbulent scalar flux. With this constrain, the mean scalar profile of the inner layer can be accurately obtained while the small-scale structures in scalar field are still retained. The method is validated by the comparison with DNS of channel turbulence with passive scalar, and the results suggest that the current method can successfully resolve the log-layer mismatch in mean scalar profiles. The method can accurately generate the mean scalar profile, scalar fluctuation profile, turbulence scalar flux, and global Nusselt number for a wide range of Reynolds and Prandtl numbers in channel turbulence.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126892"},"PeriodicalIF":5.0,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576848","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":"Numerical study of the flow boiling cooling performance of leaf vein manifold microchannels","authors":"Keyi Huang ,&nbsp;Guiping Lin ,&nbsp;Yuandong Guo ,&nbsp;Jiayi Bao ,&nbsp;Hongxing Zhang ,&nbsp;Jianyin Miao","doi":"10.1016/j.ijheatmasstransfer.2025.126919","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126919","url":null,"abstract":"<div><div>The operational reliability of advanced semiconductor devices is contingent upon the effectiveness of heat dissipation methods. Extensive investigations have been conducted into the potential of manifold microchannels as a promising near-junction heat dissipation method. However, studies combining natural structures with manifold microchannels have been relatively scarce, particularly in the context of flow boiling. This paper proposed a leaf vein manifold microchannel heat sink. The thermal-hydraulic performance and flow distribution characteristics of symmetric and asymmetric arrangements are comparatively analyzed by VOF transient flow boiling simulations. In comparison to straight microchannels, the leaf vein microchannels exhibited an increase in the wetted area and a reduction in the skewness of the flow distribution by 18%. These improvements contributed to a 4K cooler heated surface at 100 W/cm². In addition, the asymmetric leaf vein microchannels reduced the thermal resistance by 5% in comparison to the symmetric structure, while the pressure drop remained unaltered. The enhancement of the asymmetric leaf vein structure on the thermal-hydraulic performance was found to be consistent across different heat fluxes and inlet velocities. Furthermore, it was observed that doubling the inlet flow rate resulted in a 29.7% reduction in thermal resistance of the heat sink, accompanied by a 130.6% increase in pressure drop. It is therefore recommended that a lower flow rate be employed to minimize the pumping power. The asymmetric leaf vein manifold microchannel proposed in this work demonstrated enhanced flow and heat transfer performance through structural adjustments, which has the potential to be applied to two-phase embedded cooling.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126919"},"PeriodicalIF":5.0,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576739","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":"Enhanced flow boiling heat transfer performance of counter-flow interconnected microchannels via microporous copper surfaces","authors":"Dahai Wang ,&nbsp;Chaoyang Zhang ,&nbsp;Fangjun Hong","doi":"10.1016/j.ijheatmasstransfer.2025.126905","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126905","url":null,"abstract":"<div><div>Enhancing flow boiling performance within microchannels is crucial for cooling high-power electronic devices. Based on the concept of “equalizing channel dryness”, a counter-flow interconnected microchannel structure was proposed to enhance flow boiling. To investigate the flow boiling heat transfer characteristics, enhancement effects, and mechanisms of the combination of microporous layer-modified surfaces formed by copper powder sintering and counter-flow interconnected microchannels, this study employed microporous layers formed on microchannel sidewalls as an enhancement method. A detailed study was conducted on the effects of microporous layer morphology, copper powder particle size, sintering thickness, and sintering position on flow boiling heat transfer characteristics. Additionally, a mechanistic analysis of the capillary wicking process within the sintered copper powder surface was performed. The results show that, compared to smooth surface counter-flow connected microchannels, the microporous layer formed by copper powder sintering significantly enhances flow boiling heat transfer performance, as evidenced by a lower onset boiling superheat, increased critical heat flux (<em>q</em>_CHF), and improved heat transfer coefficient (HTC-<em>h_tp</em>). Furthermore, microchannels with microporous layer sidewalls exhibit a relatively uniform liquid film distribution, which helps maintain annular flow, promotes thin film evaporation, and effectively prevents local dryout caused by film rupture or bubble nucleation. The wicking ability (<em>V</em>΄) of the microporous layer is found to have a strong linear relationship with the critical heat flux (CHF).</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126905"},"PeriodicalIF":5.0,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576844","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":"Additively manufactured compact water-cooled refrigerant condenser","authors":"Omar M. Zaki ,&nbsp;Robert A. Stavins ,&nbsp;Mario Wenzel ,&nbsp;Andrew Musser ,&nbsp;Darin Sharar ,&nbsp;Stefan Elbel ,&nbsp;Nenad Miljkovic ,&nbsp;William P. King","doi":"10.1016/j.ijheatmasstransfer.2025.126836","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126836","url":null,"abstract":"<div><div>Two-phase heat exchangers are widely used in the power and process industries, heating ventilation and air conditioning, refrigeration, and electronics thermal management. This work presents the design, manufacturing, and performance evaluation of an additively manufactured (AM) water-cooled R134a condenser heat exchanger. The condenser design includes internal three-dimensional (3D) structures enabled by AM that are not possible from traditional manufacturing technologies. Our novel design methodology uses a physics-based model to rapidly search the large design space, followed by detailed computational fluid dynamics (CFD) simulations that verify performance. The design employs alternating channels for water and refrigerant flow, with optimized 3D shapes that enhance the heat transfer with wavy fins on the water side and chevrons on the refrigerant side. Experiments demonstrate that the AM condenser has a heat transfer rate of 3 kW to 8 kW for refrigerant saturation temperatures of 35 to 49 °C. The AM condenser has a power density as high as 6.2 MW/m³, outperforming traditional shell-tube designs by 30–50% with comparable normalized pumping power. The developed methods provide a robust framework for the design of high performance and high volumetric power density AM heat exchangers.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126836"},"PeriodicalIF":5.0,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576842","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":"Reducing temperature inhomogeneity in 280Ah lithium-ion battery and battery pack by single phase immersion cooling strategy","authors":"Peizhao Lyu ,&nbsp;Yunlong Xiao ,&nbsp;Xianglong Fan ,&nbsp;Zonghao Wang ,&nbsp;Zhenhua An ,&nbsp;Xinjian Liu ,&nbsp;Zhonghao Rao","doi":"10.1016/j.ijheatmasstransfer.2025.126917","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126917","url":null,"abstract":"<div><div>The energy storage stations (EESs) exhibit a larger scale and more pronounced safety concerns than electric vehicles (EVs). Presently, EESs predominantly employ large-capacity lithium-ion batteries (Nominal capacity ≥280Ah) as the primary energy storage units, which possess a more distinct necessity of thermal management compared to their smaller batteries. To ensure the safety of EESs, this study conducted a series of analysis on the single-phase immersion cooling strategy, with a focus on key parameters such as coolants, flow direction, flow rate, and battery gap to evaluate their impact on temperature rise (<span><math><mi>T</mi></math></span>), module temperature difference (<span><math><mrow><mstyle><mi>Δ</mi></mstyle><msub><mi>T</mi><mrow><mi>b</mi><mi>e</mi><mi>t</mi><mi>w</mi><mi>e</mi><mi>e</mi><mi>n</mi><mo>−</mo><mi>c</mi><mi>e</mi><mi>l</mi><mi>l</mi><mi>s</mi></mrow></msub></mrow></math></span>), and battery temperature difference (<span><math><mrow><mstyle><mi>Δ</mi></mstyle><msub><mi>T</mi><mrow><mi>i</mi><mi>n</mi><mo>−</mo><mi>c</mi><mi>e</mi><mi>l</mi><mi>l</mi><mi>s</mi></mrow></msub></mrow></math></span>). The results demonstrated that the immersion battery thermal management strategy (IBTM) can effectively control <span><math><mi>T</mi></math></span> and reduce temperature inhomogeneity in battery module, maintaining <span><math><mi>T</mi></math></span> within 30 °C, keeping <span><math><mrow><mstyle><mi>Δ</mi></mstyle><msub><mi>T</mi><mrow><mi>b</mi><mi>e</mi><mi>t</mi><mi>w</mi><mi>e</mi><mi>e</mi><mi>n</mi><mo>−</mo><mi>c</mi><mi>e</mi><mi>l</mi><mi>l</mi><mi>s</mi></mrow></msub></mrow></math></span> within 0.5 °C and reducing <span><math><mrow><mstyle><mi>Δ</mi></mstyle><msub><mi>T</mi><mrow><mi>i</mi><mi>n</mi><mo>−</mo><mi>c</mi><mi>e</mi><mi>l</mi><mi>l</mi><mi>s</mi></mrow></msub></mrow></math></span> to 2.18 °C. Besides, flow directed along the thickness of the battery (Flow I) is more effective in reducing temperature inhomogeneity. Although Mineral Oil (MO) and AmpCool AC-100 (AC-100) exhibit relatively poor temperature control ability at low Reynolds numbers (<em>Re</em>), they demonstrate greater promising capabilities at higher <em>Re</em> values. This study is of great significance for promoting the optimization and safety design of large-capacity lithium-ion battery modules and improving the safety performance of EESs.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126917"},"PeriodicalIF":5.0,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576849","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":"Thermal analysis of dual-phase-lag model in a two-dimensional plate subjected to a heat source moving along elliptical trajectories","authors":"Kaiyuan Chen,&nbsp;Zhicheng Hu,&nbsp;Yixin Xu","doi":"10.1016/j.ijheatmasstransfer.2025.126880","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126880","url":null,"abstract":"<div><div>We focus on the study of heat transfer behavior for the dual-phase-lag heat conduction model, which describes the evolution of temperature in a two-dimensional rectangular plate caused by the activity of a point heat source moving along elliptical trajectories. The Green’s function approach is applied to derive the analytical solution of the model into a series. Benefiting from the periodic motion of the heat source, all coefficients of the series would be efficiently calculated by numerical integration. Using this representation of the solution, thermal responses for the underlying heat transfer problem, including the relations between the moving heat source and the concomitant temperature peak, the influences of the pair of phase lags and the angular speed of heat source on temperature, are then investigated, analyzed and discussed in detail for three different movement trajectories. Compared with the results revealed for the common situation that the heat source moves in a straight line with a constant speed, the present results show quite distinctive thermal behaviors for all cases, which subsequently can help us to better understand the internal mechanism of the dual-phase-lag heat transfer subjected to a moving heat source with curved trajectory.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126880"},"PeriodicalIF":5.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576843","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":"Uncertainty measurement of two color two dye laser-induced fluorescence thermometry and application thereof to superheated liquid jet","authors":"Hyunchang Lee","doi":"10.1016/j.ijheatmasstransfer.2025.126908","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126908","url":null,"abstract":"<div><div>Flash boiling spray is a highly interesting phenomenon in various industries, and it is known that bubble generation and growth by phase change and heat transfer in a metastable state governs the development of the spray. To understand this phenomenon deeply, knowing the temperature field is crucial. Therefore, 2c LIF, one of the most promising non-intrusive measurement techniques, should be thoroughly checked for its strengths and weakness. In this experimental study, the performance of thermometry using fluorescein disodium and sulforhodamine was evaluated by using a jet of water at various injection temperatures from 25 – 84.5 °C. The precision was assessed according to the error propagation model considering shot and camera noise and compared with the measured one. The measured precision was around 2 % over 60 °C with available room for further improvement. As potential error sources, the effects of stray light inside the chamber and morphology dependence resonance are discussed. The jet of which injection temperature is about 91 °C was injected into the chamber in a pressure of 5 – 11 kPa, and two disintegration regimes were observed according to superheat, the number of generated nuclei, and resultant heat transfer. The temperature fields of superheated liquid in both regimes were measured, and their physical plausibility is discussed.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126908"},"PeriodicalIF":5.0,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143563083","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":"Exploring serpentine cold-plate designs for efficient cooling of Li-ion pouch cells: A computational analysis","authors":"Ajay Vishwakarma,&nbsp;Uttam Rana","doi":"10.1016/j.ijheatmasstransfer.2025.126896","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126896","url":null,"abstract":"<div><div>Efficient thermal management is essential for enhancing the performance of electric vehicles, particularly in optimizing battery efficiency. This study investigates the effectiveness of a cold plate for cooling a 20 Ah pouch-type LiFePO₄ battery, focusing on various operational and design parameters using numerical simulations. The critical parameters examined include battery discharge rate, coolant mass flow rate, coolant inlet temperature, coolant flow direction, and channel height. The study reveals that while increasing the coolant mass flow rate initially reduces the maximum temperature (<em>T</em>_<em>max</em>) and standard temperature deviation (<em>T</em>_<em>σ</em>), benefits diminish beyond a flow rate of 0.75 g/s, which also increases power requirements. Coolant inlet temperature does not yield substantial benefits on battery surface temperature deviation, especially when the ambient temperature falls within the battery's optimal operating range. The direction of coolant flow is crucial, with top and bottom inlet modes performing better in reducing <em>T</em>_<em>max</em>, while the cross-inlet mode is more effective in controlling <em>T</em>_<em>σ</em> compared to the other mode of the inlet. The bottom inlet mode provides the best overall performance, considering heat extraction and power requirements. Additionally, variations in channel height show minimal impact on <em>T</em>_<em>max</em> and <em>T</em>_<em>σ</em> but result in significant reductions in pressure loss (40.14 %) and system weight (3.2 %), potentially lowering operational costs and extending vehicle range. Overall, the findings highlight the trade-offs in optimizing cooling strategies and design parameters for enhanced battery performance in electric vehicles.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126896"},"PeriodicalIF":5.0,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143563081","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":"Heat transfer enhancement of N-Ga-Al semiconductors heterogeneous interfaces","authors":"Wenzhu Luo ,&nbsp;Ershuai Yin ,&nbsp;Lei Wang ,&nbsp;Wenlei Lian ,&nbsp;Neng Wang ,&nbsp;Qiang Li","doi":"10.1016/j.ijheatmasstransfer.2025.126902","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126902","url":null,"abstract":"<div><div>Heat transfer enhancement of N-Ga-Al semiconductor heterostructure interfaces is critical for the heat dissipation in GaN-based electronic devices, while the effect of the Al_xGa_(1-x)N transition layer component concentration and thickness on the heat transfer mechanism at the GaN-AlN interface is unclear. In this paper, using molecular dynamics simulations based on machine learning potentials, the interfacial thermal conductance (ITC) between GaN-Al_xGa_(1-x)N, AlN-Al_xGa_(1-x)N and GaN-Al_xGa_(1-x)N-AlN heterostructure interfaces are calculated for different transition layer thicknesses with different concentrations of Al fractions, and the reasons for the change of ITC and its heat transfer mechanism were explained by the phonon density of states and the spectral heat current. GaN-AlN heterostructure ITC at 300 K is calculated to be 557 MW/(m²K), and the ITCs of GaN-Al_0.5Ga_0.5 N and AlN-Al_0.5Ga_0.5 N are improved by 128 % and 229 % compared to GaN-AlN, whereas the ITCs of GaN-Al_0.7Ga_0.3N-AlN containing a 0.5 nm transition layer improved by 27.6 %. This is because elemental doping enhances phonon scattering near the interface thereby promoting phonon energy redistribution, but the bulk thermal resistance of the Al_xGa_(1-x)N layer also increases rapidly with increasing doping ratio, and ITC is affected by a combination of these two factors. This work aims to understand the mechanism of transition layer component concentration and thickness on the heat transfer at the GaN-AlN contact interface, which provides a useful guide for better thermal design of the GaN-AlN heterostructure interface.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"244 ","pages":"Article 126902"},"PeriodicalIF":5.0,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143563082","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":"Assessment of the Oberbeck–Boussinesq approximation for buoyancy-driven turbulence in air","authors":"A. Cimarelli ,&nbsp;A. Fenzi ,&nbsp;D. Angeli ,&nbsp;E. Stalio","doi":"10.1016/j.ijheatmasstransfer.2025.126851","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.126851","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The full mathematical representation of natural convection is very complex, as it involves, besides continuity and the equations for the transport of momentum and energy, one state equation for density and three laws for the dependency of the thermophysical parameters on pressure and temperature. In addition it requires the representation of pressure work and viscous dissipation in the energy equation. Most numerical simulations and theoretical studies of natural convection use a simplified model based on the Oberbeck–Boussinesq approximation. With respect to the general formulation, the simplified problem is characterized by a divergence-free velocity field, uses constant thermophysical parameters and neglects viscous dissipation and pressure work. Although the Oberbeck–Boussinesq equations have become a physical case in themselves, in certain flow conditions non-Oberbeck–Boussinesq phenomena are non-negligible thus significantly affecting the flow solution. The aim of the present work is to quantitatively identify the flow conditions that give rise to non-negligible non-Oberbeck–Boussinesq phenomena. We demonstrate that the use of direct numerical simulation data combined with the theoretical framework provided by Gray and Giorgini (1976) represents a sound practice to address this issue. The test-case selected is the Rayleigh–Bénard problem at Ra&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;7&lt;/mn&gt;&lt;mo&gt;×&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; with air as working fluid. Direct numerical simulations carried out using the compressible, variable property formulation and the Oberbeck–Boussinesq approximation highlight that a 5% tolerance on variations of the thermophysical properties of air around the reference state &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;Θ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̃&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;P&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̃&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; = (30 °C, 1 atm) only marginally affects the statistical values of both global and local quantities. However, this tolerance represents a very stringent condition that for a tank of height &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̃&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; m filled with air at a reference state &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;Θ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̃&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;P&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̃&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; = (30 °C, 1 atm) leads to a rather low maximum Rayleigh number of the order of &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; that can be investigated without considering the influence of non-O","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"243 ","pages":"Article 126851"},"PeriodicalIF":5.0,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143549278","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}