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The Consteel electric arc furnace (EAF) has gained rapid development in the field of EAF steelmaking due to its advantageous features including short tap‐to‐tap time, low production energy consumption, and waste heat recovery. However, the low heat transfer efficiency from gas to scrap has remained a persistent technical challenge in Consteel EAF. This research establishes a scrap preheating model for the Consteel EAF to comprehensively investigate the heat transfer efficiency from gas to scrap. The calculation results demonstrate that the heat transfer efficiency from gas to scrap can be effectively enhanced by increasing the initial gas velocity and scrap porosity. Specifically, raising the initial gas velocity from 0.9 to 1.5 m s−1 improves convective and radiative heat exchange, leading to increased heat transfer efficiency from gas to scrap at the same positions within the scrap layer. Moreover, increasing the scrap porosity from 0.92 to 0.98 significantly enhances the heat transfer efficiency through augmented radiation heat exchange. Notably, the improvement in heat transfer efficiency resulting from increased porosity is considerably greater than that achieved through increased gas velocity. The findings of this study hold significant practical implications for the actual field production operations in the horizontal continuous feeding system of EAF. [ABSTRACT FROM AUTHOR]

Upgrading the available dielectric materials is the most effective approach to solve the poor quality of signal transmission and heat buildup caused by high density integration. In this work, a design strategy for multilayer 3D porous composite networks is proposed, relying on the self‐assembly effect of “crystal‐like phase” to achieve the synergistic optimization of low permittivity and high thermal conductivity of polyimide. The obtained three‐layer porous polyimide composite film (PSLS) features an ultralow permittivity of 1.89, an in‐plane thermal conductivity as high as 13.58 W m−1 K−1, and maintains well electrical insulating property. Inspiringly, the first digital thermoacoustic generator with wide frequency response has been designed based on PSLS film. It achieves sound pressure levels up to 60.1 dB in the 20–100 kHz range and integrates the efficient sound generation of an ultrasonic generator with real‐time display. This work will provide a novel concept material for the smart electronics and electrical fields. [ABSTRACT FROM AUTHOR]

In order to understand the effect of different tube structures on the heat transfer characteristics of supercritical CO2 in heating serpentine micro‐tubes, five structures are investigated. At the same inlet Reynolds number, because the periodic disturbance frequency of boundary layer and centrifugal force decrease with the increase of curvature radius and the boundary layer thickens with the increase of tube diameter, the comprehensive heat transfer performance of serpentine micro‐tubes decreases with the increase of curvature radius and tube diameter. Gravitational buoyancy is independent of curvature radius but increases with the increase of tube diameter. Centrifugal force and centrifugal buoyancy decrease with the increase of curvature radius and tube diameter. [ABSTRACT FROM AUTHOR]

Rotating surfaces are used as essential tools for certain engineering applications such as mixing processes, rolling mills, bearings and seals, etc. Rotating surfaces in engineering applications generate heat, and incompressible flows are often employed in cooling systems to maintain optimal operating temperatures. Leading researchers attempted a variety of approaches to figure out the many physical characteristics. In the present study, the hydromagnetic effect and the radiation‐induced rotational stretching/shrinking interface of a dissipative hybrid nanofluid are examined while accounting for joule heating. The hybrid water‐based solution which generates the nanofluid is composed of silver and molybdenum tetra sulphide particles. The implications of viscous dissipation, thermal radiation and also the heat source are all taken into account in the governing equations for flow and heat transmission, which are built using conservation laws. To observe particle form effects on the characteristics of a nanofluid the Hamilton–Crosser model is also take into consideration. A magnetic field is incorporated into the study in order to determine magnetohydrodynamics (MHD) influences the flow characteristics. The modelled problem equipped with aforesaid properties are transformed to ordinary for the suitable choice of similarity rules and then numerical technique is adopted to handle the governing equations. The influence of many features such as the shape factor, magnetic field, and joule, are carefully examined in the study. [ABSTRACT FROM AUTHOR]

Boosting heat transfer of ultrahigh temperature ceramics (UHTCs) with dimensional‐crossover graphene has become an increasing challenge for improving the thermal protective performance of new‐generation spacecraft. Yet its characteristics of anisotropic and high interfacial thermal resistance inevitably cause heat transfer deterioration at high temperatures. Here we develop a few ZrB2/graphene/ZrB2 interface‐dominated diffuse models that are driven by bonding configurations and thermal converger. It has been found that forming stronger bonding configurations by Zr‐C interfacial bonding and designing a preferred thermal converger by ordered graphene are both unarguable ways of suppressing high‐temperature heat transfer deterioration. Each Zr‐C interfacial bonding serves as an independent sluice gate to accelerate heat flow. More high‐frequency phonons are excited at high temperature, which augments the interfacial thermal conductance from 38.5 to 335.4 MW·m−2·K−1 at 700 K. Impressively, a concept of thermal converger inspires us to adopt ordered graphene for changing the diverging behavior in isotropic ZrB2 composites. Its convergent process combines with anisotropic characteristics to transform the isotropic heat flow into the highly ordered graphene. Their thermal conductance can be regulated from minimum (2.5) to maximum (80.8 W·m−1·K−1) by rotating the ordered graphene from 90° to 7.5°. This work paves an optimal way for manipulating the heat transfer of UHTCs. [ABSTRACT FROM AUTHOR]

Crystallization fouling, a process where mineral scales form on surfaces, is of broad importance in nature and technology, negatively impacting water treatment and electricity production. However, a rational methodology for designing materials with intrinsic resistance to scaling and scale adhesion remains elusive. Here, guided by nucleation physics, this work investigates the effect of coating composition and surface structure on the nucleation and growth mechanism of scale on metallic heat transfer surfaces nanoengineered by large‐area techniques. This work observes that on hydrophilic nanostructured copper, despite its significantly enlarged surface area compared to smooth surfaces, scale formation is substantially suppressed leading to sustained, efficient cooling performance. This work reveals the mechanism through thermofluidic modeling coupled with in situ optical characterization and show that surface bubble formation through degassing is responsible for generating local hot spots enhancing supersaturation. This work then demonstrates a scalephobic nanostructured surface which reduces the accumulated surface scale mass 3.5× and maintains an 82% higher heat transfer coefficient compared to superhydrophobic surfaces with corresponding energy conversion savings. This work not only advances the understanding of fouling mechanisms but also holds promise for practical applications in industries reliant on efficient heat transfer processes. [ABSTRACT FROM AUTHOR]

This study analytically investigates the dynamics of nanoparticle transport within a three‐dimensional porous cylinder simulating a lymphatic vessel, without external heat sources. The governing equations and boundary conditions are transformed to yield a system of ordinary differential equations, which are solved numerically using MATLAB built‐in function, bvp4c. Key parameters are visually examined and physically interpreted in relation to temperature, velocity, concentration, and Nusselt number profiles. The study reveals that the distribution of temperature and Nusselt number are maximized by increasing the heat transfer coefficient, whereas NP concentration is increased by decreasing it. Furthermore, the Brownian motion parameter enhances both heat transmission and NP concentration. It is also observed that simpler extravasation into lymphatics decreases tissue nanoparticle levels and heat conduction. Ultimately, optimal intra‐lymphatic nanoparticle distribution pathways are achieved by specifically varying heat transfer and interstitial mass flux patterns. By simulating biological barriers and lymphatic drainage, this model enhances our understanding of the underlying transport mechanisms controlling nanoparticle mobilization. [ABSTRACT FROM AUTHOR]

In this article, we present a numerical study of unsteady flow and heat transfer in a viscous‐based nanofluid, examining the impact of microorganisms on a moving surface emerging from a moving slot. This gives rise to a new type of boundary layer flow, which can resemble that over a stretching or shrinking surface depending on the motion of the slot. To solve the partial differential equations governing the bio‐convectional flow, we employ the Blasius–Rayleigh–Stokes variable and transform the equations into a corrected similar form. Our numerical solutions reveal the presence of dual solutions within a specific range of the moving slot parameter. Our findings have important implications for understanding the behavior of nanofluids and microorganisms in dynamic flow environments. [ABSTRACT FROM AUTHOR]

ABSTRACT Energy piles are commonly deployed in vertically layered geological conditions due to the geological structure and pile foundation backfill. The imperfect contact between adjacent soil layers results in resistance to heat transfer at the interface, known as the interfacial thermal resistance effect. In this paper, the energy pile was simplified as a finite‐length solid cylindrical heat source, and an analytical model was established for layered heat transfer of energy piles considering the interfacial thermal resistance effect. The Laplace‐domain solutions to the temperatures in the layered ground were derived by using the finite Hankel and Laplace transforms. The Crump method was subsequently employed to numerically invert Laplace‐domain solutions to the time‐domain solutions. The proposed model was validated by comparing with an analytical solution of a homogeneous model and COMSOL numerical solution. These solutions were used to analyze the temperature response around energy piles considering interfacial thermal resistance. Finally, a parametric study was performed to explore the effects of interfacial thermal resistance and other thermal properties of the soil layer on the layered heat transfer of energy piles. [ABSTRACT FROM AUTHOR]

Due to the complexity of the internal pore structure of petroleum coke loose particle‐packed beds, measuring their thermal conductivity has always been a challenging problem. This work independently developed an experimental apparatus for testing the thermal conductivity of petroleum coke particle‐packed beds and constructed a forward calculation model for the heat transfer process, which was based on one‐dimensional unsteady heat transfer. Using the Sparse Nonlinear OPTimizer (SNOPT) algorithm, a mathematical relationship between the thermal conductivity λ of the coke bed, temperature T, and equivalent particle diameter dp was established through inverse modeling. Concurrently, a digital model of the petroleum coke particle packed bed was derived utilizing three‐dimensional computed tomography (CT) scanning technology, and a pore‐scale gas–solid radiation heat transfer model was formulated based on CFD simulation technology, thereby further elucidating the heat transfer mechanism within the petroleum coke particle packed bed. The research results indicate that the temperature predicted by the established thermal conductivity model aligns well with experimental data. Further CFD simulation studies demonstrate that a smaller particle size leads to a larger temperature difference between the wall and the center of the packed bed, while a higher gas velocity results in a smaller temperature difference, with a linear correlation observed between these two factors. At high temperatures, thermal radiation between particles in the porous petroleum coke‐packed bed plays a dominant role. The research outcomes can offer significant theoretical support for a profound analysis of the heat transfer behavior of petroleum coke‐packed beds within a vertical shaft calciner. [ABSTRACT FROM AUTHOR]

Rare‐earth based double perovskites (DPs) have attracted much attention due to stable, efficient, and unique luminescence, and wide applications in many optoelectronic fields. However, their weak near‐infrared (NIR) emission and poor anti‐thermal quenching severely limit the further applications. Herein, Sb3+‐doped Cs2KYbCl6 DP with cyan self‐trapped exciton (STE) and NIR emission is prepared by a solvothermal method, and the separate photoluminescence quantum yields from STE and NIR emission reached ≈26.1% and 43.8%, respectively. More importantly, Sb3+ not only contributes to the absorption and energy transfer but also helps to establish an effective thermally enhanced energy transfer channel through self‐trapping state, resulting in the NIR emission with superior anti‐thermal quenching resistance. The thermal sensitivity of luminescence intensity ratio (LIR) of I1010 nm/I505 nm (I is the intensity of PL) and time‐resolved temperature sensor reach 21.4 and 13.6% K−1, respectively, which are ahead of most temperature sensing materials. Furthermore, it is found that the material exhibited advanced multifunctional applications in LED lighting, flexible luminescent thin film, and NIR imaging. This work provides in‐depth understanding on photophysical mechanisms of rare‐earth luminescent materials and references for designing high‐performance materials. [ABSTRACT FROM AUTHOR]

Heat transfer in the human eyeball, a complex organ, is significantly influenced by various pathophysiological and external parameters. Particularly, heat transfer critically affects fluid behavior within the eye and ocular drug delivery processes. Overcoming the challenges of experimental analysis, this study introduces a comprehensive three‐dimensional mathematical and computational model to simulate the heat transfer in a realistic geometry. Our work includes an extensive sensitivity analysis to address uncertainties and delineate the impact of different variables on heat distribution in ocular tissues. To manage the model's complexity, we employed a very fast model reduction technique with certified sharp error bounds, ensuring computational efficiency without compromising accuracy. Our results demonstrate remarkable consistency with experimental observations and align closely with existing numerical findings in the literature. Crucially, our findings underscore the significant role of blood flow and environmental conditions, particularly in the eye's internal tissues. Clinically, this model offers a promising tool for examining the temperature‐related effects of various therapeutic interventions on the eye. Such insights are invaluable for optimizing treatment strategies in ophthalmology. [ABSTRACT FROM AUTHOR]

High‐repetition‐rate free‐electron lasers impose stringent requirements on the thermal deformation of beamline optics. The Shanghai HIgh‐repetition‐rate XFEL aNd Extreme light facility (SHINE) experiences high average thermal power and demands wavefront preservation. To deeply study the thermal field of the first reflection mirror M1 at the FEL‐II beamline of SHINE, thermal analysis under a photon energy of 400 eV was executed by fluid and solid heat transfer method. According to the thermal analysis results and the reference cooling water temperature of 30 °C, the temperature of the cooling water at the flow outlet is raised by 0.15 °C, and the wall temperature of the cooling tube increases by a maximum of 0.5 °C. The maximum temperature position of the footprint centerline in the meridian direction deviates away from the central position, and this asymmetrical temperature distribution will directly affect the thermal deformation of the mirror and indirectly affect the focus spot of the beam at the sample. [ABSTRACT FROM AUTHOR]

Introduction: The objective of this experiment was to investigate the thermal effects on hyaluronic acid fillers, PCL fillers, and PDO threads when exposed to controlled heat. This study aims to provide insights into how these materials respond to thermal energy, which is crucial for safe and effective cosmetic procedures involving combined modalities. Materials and Methods: Cadaveric tissue was utilized to simulate clinical conditions. Hyaluronic acid fillers were injected at approximately 1 mm and 5 mm thicknesses, with variations in G' value (high and low). PCL fillers were similarly injected in 1 mm and 5 mm thicknesses. PDO threads were also inserted. All materials were injected at a depth of 2 cm. A thermometer was used to measure heat penetration, and a multi‐wavelength laser was applied to the tissue. The temperature was maintained at 60°C for 5 min to assess whether heat penetrated more than 3 cm in thickness. Observations were made regarding the heat distribution and any physical changes in the fillers and threads. Results: In thick layers, heat accumulated above the PCL filler without penetrating deeper layers. In thin layers, heat penetration was observed. For the HA fillers, heat energy was not blocked, regardless of the G' value or thickness. For the threads, no significant heat blockage effect was observed. For all materials, no visual changes were detected in any of the materials due to temperature exposure. Discussion: The findings suggest that the thickness and composition of fillers significantly influence heat penetration. Thick PCL fillers act as a thermal barrier, whereas thin PCL fillers allow deeper heat penetration. Hyaluronic acid fillers do not impede heat transfer, regardless of their physical properties. PDO threads do not exhibit any notable thermal resistance. These insights are essential for optimizing the safety and efficacy of combined filler and energy‐based device treatments in esthetic medicine. [ABSTRACT FROM AUTHOR]

Conventional fluids used in fission‐based water‐cooled nuclear reactors have lower heat transfer coefficients (HTCs) and thermal conductivity, which has led researchers to explore high‐performance fluids that can enhance heat transfer in routine operation and prevent core meltdown in the case of accidents. It is important to investigate a wide range of fluids that can help designers improve thermal hydraulic characteristics, such as HTC, critical heat flux, and minimum departure from nucleate boiling ratio (MDNBR). In this study, the effectiveness of nanofluids in enhancing heat transfer parameters, including thermal conductivity and heat capacity, was investigated. Four different nanofluids (Al2O3–H2O, ZrO2–H2O, Ag–H2O, and Si–H2O) with pure water as the primary coolant in an HPR‐1000 nuclear reactor were compared using computational methods. Due to computational limitations, only the flow channel among four fuel rods with the highest power density in the core was simulated using Eulerian computational fluid dynamics. The results of this study show that silver water (Ag–H2O) nanofluid outperformed other nanofluids and pure water. It had a higher average HTC and MDNBR, with a 67.15 % and 45.23 % improvement, respectively, compared to pure water. The fuel rod wall temperature was also reduced by 28.5 K with Ag–H2O compared to water. Comparison of current simulated results with literature data shows a good agreement. [ABSTRACT FROM AUTHOR]

This study investigates the fluid flow, heat, and mass transfer phenomena within a vertical channel containing two immiscible fluids, with a particular focus on slip effects. These effects include no slip, velocity slip, thermal slip, and multiple slips, each analyzed with appropriate boundary conditions. The study thoroughly examines key characteristics, such as variations in thermal conductivity and viscosity. Using a sixth‐order Runge–Kutta numerical method implemented using Mathematica, the study achieves precise solutions for complex scenarios. The detailed results show how the various slip mechanisms and relevant parameters interact with each other in complex ways. These findings are useful for both theoretical understanding and application in real‐life engineering situations. This study also gives important information about how fluid flow, heat transfer, and mass transfer change under different slip effects. It looks at these effects and shows how they change visually. It also carefully calculates and analyzes engineering parameters like the Nusselt number, shear stress, and Sherwood number using bar charts, showing how they affect and behave. The study resulted in velocity slip having a minimal impact on temperature, whereas thermal slip resulted in higher temperatures. Both velocity and thermal slip conditions simultaneously result in the lowest temperatures. [ABSTRACT FROM AUTHOR]

Heat transfer characteristics in the electromagnetohydrodynamic flow of a third‐grade fluid between parallel plates have already been examined by researchers, but studies on the effect of temperature‐dependent viscosity on velocity, temperature, and heat transfer coefficients are very few. The present study investigates the heat transfer behavior of a third‐grade fluid flow between large parallel plates, taking temperature‐dependent viscosity when magnetic and electric fields are imposed externally. The plate walls are subjected to uniform temperatures. Consideration of temperature‐dependent viscosity results in the formulation of the phenomenon by nonlinear, coupled differential equations, which are solved by applying the least‐square method (LSM). Solving coupled, nonlinear equations by the LSM requires a great deal of modification in the implementation process. The obtained results in terms of dimensionless velocity are validated with the results of earlier studies and are also in a close match with the results of the Adomian decomposition method of the current study. Results indicate that for a higher value of the viscosity parameter, at first, velocity increases with an increase in the non‐Newtonian parameter. Beyond a certain value of the non‐Newtonian parameter, velocity starts reducing. Temperature, at all points of any cross‐section, increases up to a certain non‐Newtonian parameter and then reduces with the rise in the same parameter. For higher values of the viscosity parameter and low non‐Newtonian parameters, the upper plate requires an enhanced rate of cooling. Whereas, for higher values of the non‐Newtonian parameter at higher viscosity parameters, a lower heating rate is required. The results of the mathematical model can serve to be useful in the field of liquid metal flows in metallurgical industry, micropumps, medical and biological sectors, and microelectromechanical applications. [ABSTRACT FROM AUTHOR]

The study aims to examine how duct length affects the performance of a solar air heater (SAH) with a D‐shaped ribbed absorber plate, compared to a smooth absorber plate. The optimized D‐shaped ribs from previous research investigations are utilized in the present work to explore the absorber plate's length influence on the Nusselt number. The study reveals a slight decrease in the Nusselt number as the length of the absorber plate with D‐shaped ribs is increased. The observed behavior is attributed to the diminishing capacity of air to extract heat from the heated surface within the elongated duct. Moreover, the study calculates the pressure drop and thermo–hydraulic performance parameter (THPP) associated with the D‐shaped ribs and formulates correlations to establish a quantitative understanding of the relationship between duct length and D‐shaped rib performance. The maximum value of THPP was found to be 1.17 within the considered range of duct height. Furthermore, correlations have been derived for the Nusselt number and friction factor in terms of duct length to hydraulic diameter ratio and Reynolds number with maximum deviations of +1.7 and +2.13, respectively. These correlations serve as valuable tool for engineers and researchers seeking to optimize the design of SAHs, enabling them to balance the benefits of D‐shaped ribs with the considerations of duct length. This research contributes to the growing body of knowledge of SAH design, offering insights into the trade‐offs and intricacies of utilizing D‐shaped ribs and adjusting duct length for improved THPP. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of magnetohydrodynamics and heat transfer on the peristaltic transport of Prandtl fluid in a vertical endoscopic tube. The reduction of the complexity of the equations governing the flow of Prandtl fluid entails the use of long wavelength and low Reynolds number approximations. These complex equations for the pressure gradient and velocity profile are handled analytically using the perturbation technique with convective boundary conditions, and the temperature and concentration profiles are carefully solved for the exact solution. The frictional forces and pressure rise are also simulated with numerical integration. The resulting formulas for velocity, temperature, concentration, pressure rise, and pressure gradient are graphed using the MATLAB and MATHMATICA software, and the effects of all the different physical parameters are investigated and assessed. The streamlines with five distinct wave types are sketched at the conclusion to show the phenomenon of trapping. It is investigated that the velocity profile rises due to buoyancy forces and falls due to the influence of magnetic forces. [ABSTRACT FROM AUTHOR]

The complexities of natural convection heat transfer are investigated through experimentation, focusing on the influence of geometric configurations such as spheres, cylinders, and cubes in external flows. The study aims to understand how different geometries affect heat transfer coefficients, providing insights for architectural and engineering applications. Experimental results revealed significant variations in heat transfer efficiency among geometric models, with cubic configurations exhibiting the lowest heat transfer rates compared with spherical and cylindrical counterparts. This underscores the critical impact of geometric configuration on thermal performance and heat dissipation characteristics. The findings highlight the necessity of considering geometric factors in design processes to optimize thermal management strategies. The study contributes to a deeper understanding of convective heat transfer mechanisms, emphasizing the importance of precise geometric modeling in enhancing energy efficiency and sustainability in built environments [ABSTRACT FROM AUTHOR]

India leads the world in jaggery production, with the jaggery industry being a vital rural‐based sector. The jaggery plants in the country face challenges in effectively utilizing energy, resulting in varying efficiency levels ranging from 20% to 65% across different plants. To address this, a modified approach employing open pan heat exchangers (OPHEs) in jaggery plants is proposed to enhance overall performance. The effectiveness of the heat exchanger (HE) relies on factors such as heat transfer coefficient (HTC), surface contact area, and temperature differences between surfaces and the warm liquid. Circular conduits are predominantly favored in HE design, but this study delves into the impact of conduit shapes specifically circular, semi‐circular, and square on the achievement of the HE. The study reveals that semi‐circular conduits outperform circular conduits by 25%–28% in terms of HTC, while square conduits show a 21%–24% improvement. Moreover, comparing the efficiency of a conventional open pan jaggery plant with a circular conduit OPHE and a modified version featuring semi‐circular conduits OPHE, significant improvements are noted. A one hp pump is enough to overcome the issue related to pumping power due to a change in conduit shape. Heat transfer rate (HTR) is very poor for circular conduit due to line contact, whereas HTR for semi‐circular conduit is 38%–39% better than the square conduit. Efficiency increases from 24.36% for the conventional open pan to 62.5% for the circular conduit and further to 83.22% for the semi‐circular conduit. Processing time for jaggery making also varies significantly, with 165 min for the conventional open pan, which is reduced by 33.33% for the circular conduit OPHE and 45.45% for the semi‐circular conduit OPHE. As compared to circular conduit processing time of semicircular conduit OPHE is reduced by 18.18%. [ABSTRACT FROM AUTHOR]

Experimental investigations have been conducted to study the convective heat transfer from a cylindrical solar cavity receiver with vertical fins. The experiments were performed under varying surface heat flux levels and at seven inclination angles, ranging from −90° (upward facing) to +90° (downward facing) at 30° intervals. The impact of fins on the heat transfer process was studied by conducting experiments in two scenarios, namely, finned and unfinned cavities. The findings of the study showed that with an increase in cavity inclination, the magnitude of convective heat loss decreased in both finned and unfinned cavities, while the cavity surface temperature increased. At +90° inclination, the convective heat loss and Nusselt number were observed to have the lowest value, while the surface temperature had the highest value. For a downward‐facing cavity, the fins reduced convective heat loss, leading to an increase in cavity surface temperature. The finned cavity performed better for a vertically downward‐facing inclination (+90°) as it had a contribution of only 11% for convection heat loss compared with the unfinned cavity, which had a contribution of 21% for the same. Furthermore, an empirical model was developed based on the experimental results for the Nusselt number, which correlates experimental data with an error margin of ±15%. This model can be used to predict the Nusselt number for different inclination angles and surface heat flux levels. The presence of vertical fins in the cavity was found to be effective in reducing convective heat loss, especially for downward‐facing cavities. Understanding the influence of fin and cavity inclination on convective heat transfer can lead to enhanced efficiency and performance of solar receivers, thereby increasing the overall energy output of the system. [ABSTRACT FROM AUTHOR]

The current study explores the transient magnetohydrodynamic (MHD) flow with the interaction of quadratic convection, slip of second‐order momentum, viscous dissipation, and Newtonian heating. In this setup, the governing equations become highly nonlinear. The numerical solutions are attained by utilizing an implicit type of the Crank–Nicolson technique. The primary aim of the exploration is to figure out the consequence of MHD nonlinear convection and momentum slip of second‐order on the overall behavior of the system. The robust agreement is evinced by numerical computations verified against existing research. Skin friction and Nusselt number decreases for second‐order slips, δ=0,−2,−4,−8 $\delta =0,-2,-4,-8$, and −16. And for γ=1.0 $\gamma =1.0$ and δ=‐2.0 $\delta = \mbox{-} 2.0$ the temporal coefficients of friction and heat transmission attain a steady state at time t = 29.88. It is significant that nonlinear convection predominates over viscous dissipation and that nonlinear convection is influenced by magnetic fields. The results are described using plots and tables. [ABSTRACT FROM AUTHOR]

This study performs a time‐dependent analysis of mixed convection of an incompressible fluid and heat sink/source factor in an upstanding slit superhydrophobic (SHO) microchannel in the involvement of temperature jump and electroosmotic flow conditions. The internal wall of one of the sides in the microchannel is intentionally modified to demonstrate SHO slip and temperature jump conditions. A transverse magnetic effect is introduced in the path of the flow. The steady‐state solutions of the modeled problem have been analytically derived for temperature, velocity, pressure gradient, sheer stress, and heat transfer rate. The derived results are expounded thoroughly with the use of several plots. It is deduced that the elevating mixed convection (Gre), heat source/sink (Qs), Debye–Hückel (K), and nonlinear parameters (N) are observed to increase the fluid flow as time rises, and these effects are all higher when the velocity slip and temperature jump impacts are present. Further, the application of heat‐generating parameters is viewed to encourage the fluid temperature in the microchannel. Finally, the comparison between the current investigation with the previously published findings demonstrates a very good consistency for the limiting cases. [ABSTRACT FROM AUTHOR]

This paper explores the impact of temperature on the fractionalization of magnetic nanoparticles in blood, coupled with vibratory motion influenced by rotation. The distribution systems exhibit heightened diffusivity, explored numerically through the finite difference method and the L1 ${L}_{1}$ algorithm. The temperature distribution robustly responds to elevated fractional parameters, indicating a critical threshold. The study achieves a comprehensive understanding of temperature and velocity evolution in different tube zones. In comparison, single‐walled carbon nanotubes surpass multiple‐walled carbon nanotubes in distributions, while CuO nanoparticles demonstrate larger distributions at an average fractional‐order parameter of α=0.5 $\alpha =0.5$. In the observed growth region at α=0.73,Fe2O3 $\alpha =0.73,{\text{Fe}}_{2}{{\rm{O}}}_{3}$ and TiO2 ${\text{TiO}}_{2}$ exhibit noteworthy temperature distributions, highlighting the fractional derivative's impact in highly diffusive models with nanoparticles. It is also noted that in this region, the temperature distribution tends to decrease for all the parameters and values examined, particularly at a low Reynolds number (Re=0.5 ${R}_{e}=0.5$). However, the introduction of nanoparticles accelerates the processes and distributions across the various observed zones. Furthermore, the accelerated behavior of each nanoparticle can be moderated based on its sphericity. By encompassing all facets of fractional order for controlled rotations, the study sheds light on the role of magnetized nanoparticles in blood dynamics, emphasizing the significance of a critical zone where certain physicochemical properties are disrupted, potentially leading to cellular disorders, and the fluidodynamic effects of vortex flow. This perspective is pivotal for addressing tissue lesions induced by vibrations, as seen in the case of coagulations, and for targeting carcinogenic areas using nanoelements. [ABSTRACT FROM AUTHOR]

This paper adopted the Lattice Boltzmann Method (LBM) to compute a two‐dimensional incompressible convective flow field with two isothermal elliptical sinks attached vertically to the horizontal bottom north side of the enclosure, which is subjected to a horizontal magnetic field. The attained results show that LBM can effectively capture vortex shedding structures and other features inside such complex flow. Also, the Hartmann numbers with a panoply of heated sinks location were studied, and the results showed that fluid flow and heat transfer rate depend on the Hartmann number and are greatly influenced by the heated sinks positions. The effect of the Prandtl number on the average Nusselt number is also highlighted. [ABSTRACT FROM AUTHOR]

The present study investigated the performance of dual function reverse flow solar collector (RFSC). The impact of the mass flow rate of air and water on outlet temperature, thermal performance, and overall performance of dual‐function solar air heater (SAH) has also been investigated. An experimental investigation of three different working models namely, Model‐A: SAH, Model‐B: solar water heater (SWH), and Model‐C: integrated solar air‐water heater (SAWH) for dual heating applications was performed to analyze the actual performance of these models. The investigation of the impact of time intervals on the water inlet and outlet temperatures at various mass flow rates of water is conducted to analyze the time‐varying efficiency of SWH systems. Furthermore, the effect of solar intensity on the performance of the dual‐function heating system has also been explained. The result reveals that the maximum thermal efficiency of Models: A and B can be achieved at about 78.8% and 67.9%, at a mass flow rate of 0.0644 and 0.10 kg/s, respectively, according to the experimental findings. The maximum temperature rise of air and water reaches about 52.4 and 55.58°C for Models A and B, respectively. The total efficiency of Model C reaches 81.69%, exceeding that obtained in Models A and B individually. The efficiency, outlet temperature of the fluid, and heat transfer effectiveness of the system strongly depend on the mass flow rate. The increase in heat removal factor is negligible for a higher flow rate (more than 0.10 kg/s). [ABSTRACT FROM AUTHOR]

Solar thermal collectors, such as evacuated tube collectors (ETCs), are essential for harnessing renewable energy, yet their efficiency is often hindered by thermal losses and limited heat transfer. This study focuses on enhancing ETC performance for seawater desalination by using nanofluids as heat transfer fluids. These modifications aim to improve heat transfer rates, reduce thermal losses, increase the maximum temperature attainable, and minimize the collector area required. An experimental setup has been developed at Parul University in Vadodara, Gujarat, India. Key parameters such as air mass flow rate, inclination angle, water mass flow rate, nanofluid volume percentage, and screw conveyor speed were optimized to achieve ideal temperature levels. Results indicate that the optimal configuration for steam generation includes a high air mass flow rate and a 40° inclination angle for the ETC. Additionally, a water mass flow rate of 10 LPH and a screw conveyor speed of 30 rpm are crucial for optimal performance. Data collected showed the highest solar energy levels between 12 PM and 1 PM, which significant decreases post this peak period. These findings highlight the potential of nanomaterial‐based enhancements in improving the efficiency and cost‐effectiveness of solar thermal systems for renewable energy applications. [ABSTRACT FROM AUTHOR]

The elaboration of suitable NdFeB‐based permanent magnets is essential for high‐performance electrical machines in a number of applications. In this respect, the understanding of the relationship between heat transfer phenomena and the final solidified microstructure is the key to the control of the grain size and the improvement of the magnetic properties. The problem is even more acute with the emergence of new manufacturing processes, such as the laser powder bed fusion, where the cooling rates are much higher than those encountered in the standard strip casting process and where the microstructure can be considered as fixed from the fabrication step. The objective of the present work is to identify correlations between interstructural spacings in the solidified alloys and cooling conditions. This study is based on a methodology coupling experimental and numerical simulation approaches featuring three solidification processes: strip casting, arc melting, and laser fusion. The obtained results cover more than four orders of magnitude in terms of cooling rates R and allow to propose a reliable empirical relationship between the interstructural spacing λ and R of the form λ [μm] = 83 R [K s−1]−0.36. This relation can thus be used to estimate cooling rates from metallographic observations. [ABSTRACT FROM AUTHOR]

There is great interest in developing methods to predict full‐scale fire performance of mattresses and upholstered furniture for design and regulatory purposes using cone calorimeter and other small‐scale test results. One method used in the past is a model developed during the European Combustion Behavior of Upholstered Furniture (CBUF) project. To support the further development of this model, cone calorimeter tests of polyurethane (PU) foam specimens 5–10 cm thick were conducted using incident heat fluxes between 5 and 35 kW/m2. Temperatures were measured using thermocouples located on the surface and at four depths within 10 cm thick foam specimens to determine the effects of heat flux on heat transfer and foam degradation. Peak and average heat release rate (HRR) values for a particular thickness of foam increased with an increase in heat flux. An increase in heat flux decreased the times to reach the two peaks in the HRR curve, which represent the collapse of foam and burning of liquid products, as well as burning duration. Heat flux had a larger effect on the second HRR peak than the first peak. Significant temperature gradients were initially confined to the top portion of the foam. A surface temperature of 150–200°C was shown to be indicative of the onset of ignition, while a temperature of 150°C at a particular location was indicative of when temperatures began to more rapidly increase at deeper locations within the foam. Infrared video records were also used to examine three‐dimensional burning behavior of the foam. [ABSTRACT FROM AUTHOR]

The current paper deals with viscous dissipation effects in a permeable (or porous) channel filled with non‐Newtonian Casson fluid by considering the local thermal non‐equilibrium (LTNE) model. The dependency of the effective thermal conductivities of the solid and fluid phases on the respective temperatures has been studied along with the spatially varying Biot number. The Brinkman number Br, Casson fluid parameter γ, thermal conductivity variation parameter δ, porosity ϵ, Darcy number Da, and the ratio of fluid and solid phase thermal conductivities kr=kfks are the main governing parameters. The Darcy–Brinkman model is employed to govern the fluid flow in permeable media and the velocity profile has been obtained analytically. Moreover, the energy equations for both phases along with suitable boundary conditions are derived and solved with the fourth order boundary value solver. The findings of the current study depict that the Nusselt number increases with the increment in Casson fluid parameter and decreases with the increment in Brinkman number and thermal conductivity variation parameter. Overall, the heat transmission between the solid and fluid phases increases with the decrement in Brinkman number and thermal conductivity variation parameter. On the other hand, the heat transmission between both the phases magnifies by increasing the value of Casson fluid parameter. [ABSTRACT FROM AUTHOR]

The combined implementation of porous medium and hybrid nanofluid with heaters and coolers can be an effective technique to improve the efficiency of several types of electric equipment. In this regard, the present study has been conducted to analyze the forced convection heat transfer of Al2O3‐CuO water‐based hybrid nanofluid in porous channel with pairs of heaters and coolers of various shapes. The circular and semi‐circular heaters and coolers with distinct orientations are considered. The Peclet number 25≤Pe≤200, Darcy number 10−6≤Da≤10−1, porosity 0.1≤ε≤0.9, and volume fraction of hybrid nanoparticles 0.02≤ϕ≤0.08 are chosen as the governing parameters. The governing equations are solved by using the finite element method based commercial software COMSOL Multiphysics. The acquired results exhibit that the heat transfer from heaters and coolers is enhanced by decreasing ε and Da for all the cases and values of Pe and ϕ. The lowest heat transfer has been obtained by circular heaters and coolers (case 1). Moreover, the semi‐circular heaters and coolers with curved facing towards channel inlet (case 2) and flat surface towards the bottom channel wall (case 4) show higher heat transfer compared to other cases. The average Nusselt number for case 4 is around 3.63% higher from case 2 at the highest values of the considered parameters. Case 4 shows the minimum drag coefficient and maximum heat transfer at the highest values of the governing parameters. [ABSTRACT FROM AUTHOR]

Mixed convection flows across the revolving bodies have eminent applications in science and technology, such as fibre coating, polymer deposition, centrifugal blood pumps, rotatory machinery, and so forth. In the current work, magnetohydrodynamic (MHD) flow and heat transfer characteristics of Casson hybrid nanofluid (Ag/MgO as nanoparticles) over the rotating sphere at the stagnation zone are being studied. Moreover, an analysis of heat transmission is conducted by considering the influence of thermal radiation, temperature‐dependent thermal conductivity, magnetic field, and viscous dissipation. The relevant partial differential equations are reformed into ordinary differential equations by appropriate transformations, which are solved using the successive linearization method (SLM). The thermal field, velocity components in x and z directions, heat transfer rate, and skin friction coefficient are computed for various physical quantities like rotation parameter mixed convection parameter, radiation parameter, Eckert number, Casson parameter, magnetic parameter, variable thermal conductivity parameter, and so forth. The current findings align well with the literature in a limiting sense. Thermal enhancement in hybrid nanofluid is observed for the viscous dissipation parameter (Ec), thermal conductivity parameter (ε), and radiation parameter (Rd). The degree of heat transfer rises from 12.8% to 20% when the Casson parameter's value (β0) increases. Also, a decrease of approximately 33% is depicted between the peak values of the velocity magnitude with an increase in rotation parameter. [ABSTRACT FROM AUTHOR]

The flow, heat‐transfer, and mixing behaviors of steel scraps with different amounts, positions, and sizes added from the top of the bottom‐blown 300 t ladle are numerically investigated and compared through a coupled model. In the results, it is shown that it takes 59 s to mix the temperature of molten steel after adding scrap steel at the position of x = 0 mm, y = 553.5 mm, and z = 3375 mm. The further the addition position is from the axial position of the permeable brick, the shorter the mixing time of the speed and temperature of molten steel. For the scrap amount of 0.5, 1.5, and 2.5 t, the mixing time of molten steel temperature is 44, 78, and 47 s, correspondingly, which exhibits a pattern of initial increase followed by decrease, with an ≈8 K decline in molten steel temperature for every additional 1.0 t of scrap. When considering the scrap size of 10, 30, and 50 mm, the average temperature mixing time of molten steel is 44, 61, and 45 s, respectively. In this research, theoretical guidance can be can be provided for the addition of scrap in ladle during practical production processes. [ABSTRACT FROM AUTHOR]

Thermal annealing is a critical process in producing high‐quality perovskite films for high‐performance perovskite solar cells. Conventional TA presents challenges such as delayed heat transfer, leading to unwanted crystal growth and hindering processing scalability. Solvent‐bath annealing is an attractive approach that can improve heat transfer and promote perovskite crystallization by immersing the as‐deposited precursor film in a liquid medium. In this study, fluorocarbon‐based solvents are developed as novel solvent baths for uniform heat flow through omnidirectional annealing. In addition, the previously neglected solvent‐to‐solvent interaction between fluorocarbon and solvents for perovskite precursor is investigated by comparing two fluorocarbon solvents. By increasing the solvent‐solvent interaction, higher quality perovskite films with increased crystallinity, improved perovskite transition, and reduced film defects are achieved. As a result, the perovskite solar cells exhibited an increased power conversion efficiency with excellent reproducibility. These findings suggest that the selection of suitable solvent bath is promising for further improving perovskite quality and device performance. [ABSTRACT FROM AUTHOR]

In this paper, the full compressible Navier‐Stokes equations with Cattaneo's heat transfer law or revised Maxwell's law are considered. We present a loss of initial smoothness of smooth solutions within a finite time and give an upper bound of such time. It is not required that the initial data has compact support or contains vacuum in any finite regions. Moreover, the blow‐up result has no restriction about the specific heat ratio. The main approach is motivated by previous studies and constructing a differential inequality. [ABSTRACT FROM AUTHOR]

Slag fuming (SF) is a metallurgical process designed to recycle Zn‐containing slags derived from various industrial residues. To protect the reactor from corrosive molten slag, a deliberate as‐solidified slag layer, known as a freeze lining (FL), is formed on the reactor walls using intense water‐cooled jackets. In this article, a computational‐fluid‐dynamics‐based model capable of simulating FL formation in a SF furnace is presented. To capture the complex multiphase flow dynamics, heat transfer, and FL formation during SF, a volume‐of‐fluid model is coupled with a mixture continuum solidification model. Three phases are considered: gas, liquid bulk slag, and solid slag (FL). Moreover, two types of FL are distinguished: one that solidifies on the reactor wall in the bulk slag region and another that solidifies on the reactor wall in the freeboard region owing to slag splashing. Comparisons between calculated FL thickness and heat fluxes and corresponding industrial data demonstrate satisfactory agreement. In this outcome, the robustness of the model is underscored and confidence in its accuracy is instilled. In the simulation results, valuable insights are provided into the evolution of the fuming process, particularly regarding the slag bath temperature, slag splashing dynamics, FL formation, local heat fluxes through the reactor wall, and global net energy balance. [ABSTRACT FROM AUTHOR]

Highlights To achieve the wave‐transparent and anti/de‐icing requirements of electromagnetic functional structural components on the windward surface of the aircraft, the PTFE capillary hot air tubes were pre‐buried inside the quartz fiber cloth and the hot air anti/de‐icing quartz fiber/PTFE capillary/epoxy resin (QF/PTFE/EP) composite components was prepared to that met the wave‐transparent performance. A multi‐field coupled numerical finite element simulation model was established, and the anti/de‐icing performance of the QF/PTFE/EP composite with different built‐in tube diameters were investigated by combining experiments and simulations under different hot air temperatures and pressures. The feasibility of hot air anti/de‐icing was verified through anti/de‐icing experiments and numerical simulation. The electromagnetic transmittance of the prepared hot air anti/de‐icing QF/PTFE/EP composite components was tested to characterize the effect on the stealth performance of the aircraft under the service environment. The experimental results demonstrated that with 5 mm tube pitch and hot air of 60°C ± 1°C, the surface temperature of the component with three tube diameters could reach more than 10°C. Furthermore, the decrease in the transmittance of the hot air anti/de‐icing QF/PTFE/EP composite components caused by different incidence angles and two polarization modes was less than 3%. The hot air QF/PTFE/EP anti/de‐icing composite components were fabricated. The heat transfer, anti/de‐icing, and electromagnetic transmittance performance of the hot air QF/PTFE/EP anti/de‐icing QF/PTFE/EP components were investigated. The experimental and simulation results verified the hot air anti/de‐icing QF/PTFE/EP components met the requirement of aircraft anti/de‐icing and wave transmission. [ABSTRACT FROM AUTHOR]

Thermal radiation and electrical conductivity in nanofluids are crucial for their heat transfer characteristics, especially in applications with elevated temperatures or significant radiative heat transfer. The suspension of nanoparticles in suspension contributes to the fluid's electrical conductivity, which is essential for efficient heat dissipation in electronic cooling systems. Understanding the behavior of electroconductive nanofluids is particularly important in electronic cooling applications, where effective heat dissipation is crucial to prevent overheating. A study using a similarity parameter transformed a system of coupled PDEs into a set of nonlinear ordinary differential equations, revealing significant changes in key physical characteristics, such as temperature distribution, cubic concentration field, and velocity field. The study also examined the effects of parameters like Brownian motion, Rayleigh number, Peclet number, thermophoresis parameter, and buoyancy ratio parameter. The research provides valuable insights into the complex dynamics of magnetized non‐Newtonian nanofluids and offers practical implications for applications like microbial fuel cells and heat transmission equipment. [ABSTRACT FROM AUTHOR]

Where precision is paramount in managing temperature and fluid dynamics, micro heat exchangers (MHXs) emerge as indispensable tools. This review investigates the significance of MHX technology, offering readers a comprehensive roapmap from conceptualization to market application. We dissect the nuances of material selection, shedding light on cutting‐edge advancements poised to revolutionize MHX efficiency. Furthermore, we explore how the geometry of MHX influences heat transfer dynamics and pressure drop, providing insights into enhancing the overall effectiveness. We delve into the various types of control instrumentation, offering a detailed analysis of their applicability. Beyond the technical prowess, the economic landscape plays a pivotal role in the adoption of MHX technology. [ABSTRACT FROM AUTHOR]

In this study, free‐standing composites consisting of 90 wt% nanoenergetic mesoparticles are fabricated and their combustion characteristics are investigated. The findings reveal that the integrity of the mesoparticles remains intact during the printing process and a reduction in sintering is observed for the composite of mesoparticles compared to the physical mixture. However, the composite of mesoparticles exhibits noncontinuous and oscillating propagation behavior at a steady frequency of ≈5 Hz. This is attributed to insufficient heat feedback from the flame to the unburnt material. To address this issue, carbon fiber (C.F.) is introduced into the composite to enhance heat feedback to the reaction front by intercepting hot agglomerates near the burning surface. Incorporating C.F. leads to steady propagation of the composite. Agglomerate residence time and characteristic heat transfer time analysis near the burning surface indicate that while the composite without C.F. has agglomerate residence time on the same order of magnitude as the characteristic heat transfer time, the composite with C.F. has significantly increased overall agglomerate residence time compared to the characteristic heat transfer time. This confirms the enhanced heat feedback through C.F. inclusion. This study demonstrates the crucial role of heat feedback in the combustion behavior of energetic composites. [ABSTRACT FROM AUTHOR]

Computational methods provide effective tools for the prediction of the curing behavior of composites, especially for large‐scale complex composite structures. The flow‐compaction analysis during curing receives insufficient attention in current studies. In this work, an integrated framework considering the heat transfer, the cross‐linking reaction, the flow and compaction, and the stress–strain module is established. A comprehensive resin flow termination criterion is proposed. L‐shaped composites with a stacking layer of [45/90/−45/0]s were fabricated, and the good agreement between the experimentally measured and the numerically predicted contour data validated the current model. Compared with Hubert's model, the prediction accuracy of the thickness and fiber volume content increases by 4.24% and 3.92%, respectively. Correlation analysis between the fiber volume ratio predicted by numerical methods and experimental results (94% for this method, −41% for Hubert's model) demonstrates the well‐capture of nonuniform fiber distribution in curved composites for the current strategy. The overall framework provides an accurate and promising tool for the prediction of the curing behavior of complex composite components. Highlights: An integrated numerical methodology is proposed considering the resin flow and compaction.The viscosity‐temperature coupled feature of resin is considered in the permeability coefficients.A comprehensive resin flow termination criterion is proposed for an accurate prediction.The resin content, thickness, and spring‐in angle of L‐shaped laminates are characterized.The good correlation between the experimental and numerical results validates this method.Compared with the model proposed by Hubert, the prediction accuracy improves. [ABSTRACT FROM AUTHOR]

In recent years, hexagonal boron nitride (h‐BN) has gained attention for its potential applications in thermal management and high‐temperature uses. To evaluate the environmental impact of employing h‐BN nanocomposites in microelectronics packaging for thermal management, a comprehensive assessment was conducted. This assessment is particularly significant due to the nature of nanoparticles and the importance of mitigating potential environmental toxicity. Electronic waste incineration, compared to e‐waste recycling, carries a higher environmental burden. Building on previous research, this project explores the feasibility of h‐BN nanocomposites in microelectronic packaging for thermal management. The study focuses on the physiochemical transformations of h‐BN nanocomposite underfills during incineration, considering the influence of particle size and concentration on these transformations. Various analytical techniques, including SEM, XRD, FTIR spectroscopy, and TEM, were employed to identify and characterize the particles throughout their life cycle. By delving into physiochemical transformations and investigating the effects of particle size and concentration, this research enhances our understanding of h‐BN nanocomposites, aiding informed decision‐making for environmentally sustainable use in microelectronics packaging. Highlights: h‐BN nanoparticles remained inert throughout their life cycle.Underfill characterization showed minimal physiochemical changes in h‐BN.h‐BN is a promising thermal transfer candidate in microelectronics. [ABSTRACT FROM AUTHOR]

Low‐temperature differential evaporation constitutes a promising direction for energy‐saving desalination. Herein, a novel Janus interfacial structure with well‐ordered micro/nanopores is developed. Fabricated Janus interfacial structure can weak the water intermolecular forces and pump water to the hydrophilic–hydrophobic junction. Within well‐ordered nanochannels, the increased curvature of the meniscus increases the ratio of thin water layers, thereby enhancing microscale heat transfer at the heated walls; in addition, the smaller nanopores limit the development of microscale vortices at the liquid–gas interface and prevent back mixing of intermediate water at the interface, which possess the nanoscale effect on intensifying the interfacial evaporation. These effects are validated by theoretical and experimental studies. Optimized Janus (20 nm)95°/25° structure exhibits evaporation fluxes up to 2.4 kg m−2 h−1 at 45 °C (feed side)/25 °C (permeate side, ambient pressure), as the theoretical evaporation enthalpy is only 30% of that for direct evaporation. The unique Janus structure simultaneously inhibits salt accumulation and achieve self‐cleaning, thereby maintaining steady performance during 480 h of continuous desalination and 50 cycles of batch operation. This work highlights a promising structural design strategy for separation materials with specific micro/nanoscopic topologies to achieve high performance thermally driven desalination applications. [ABSTRACT FROM AUTHOR]

Interfaces play an important role in the heat and stress transfer within applications such as electronic cooling. The coexistence of apparently contradictory properties between heat dissipation and adhesion at interfaces poses a constant challenge for existing interface materials. Herein, a thermal interface material is reported, consisting of epoxy‐functionalized polydimethylsiloxane and aluminum fillers with excellent interfacial heat/force transfer ability. This material optimizes the combination of thermal conductivity of 3.46 W m−1 K−1 and adhesion energy of 1.17 kJ m−2. Using two viscoelastic models, the excellent interfacial force transfer ability is attributed to a hierarchical energy dissipation via the introduction of borate ester bonds and the aluminum filler networks. A simple kinetic bond model demonstrates that the borate ester bonds increase molecular chain segment mobility, allowing full extension at debonding interface for stress dispersion and efficient energy dissipation. The aluminum filler networks not only facilitate thermal transfer, but also dissipate the mechanical energy during filler network destruction due to the bond breakage between fillers. The excellent heat dispassion and mechanical stability are further demonstrated when this thermal interface material is used in flexible light emitting diodes and high‐power chips. This work provides a new strategy for balancing interfacial heat and force transfer. [ABSTRACT FROM AUTHOR]

Energy‐efficient building materials are eye‐catching for reducing indoor energy consumption via eliminating electromagnetic interference and pollution, controlling the thermal transfer, and promoting sunlight harvesting and providing a comfortable living environment. To realize broadband microwave shielding, the elaborate control of microstructures has showed great potential and research direction. By composition regulation and structure design with various dimension, the synergistic effects including conductive networks, interfacial polarization, magnetic coupling, dipole polarization, and dielectric‐magnetic synergy, can significantly improve electromagnetic (EM) shielding capacity. Thermal management including thermal conversion, thermal storage, thermal radiation, and thermal conduction has enormous potential in enhancing the sustainability and energy efficiency for future buildings. Smart windows are able to switch optical transmittance and colors, which is contributed to saving building energy. Herein, in this review, the recent progress of broadband shielding, thermal management, and smart window in the field of energy‐efficient buildings is summarized, from the aspects of materials, mechanisms, and scenarios. Further, the main bottlenecks and problems are discussed, and potential research opportunities are further highlighted. [ABSTRACT FROM AUTHOR]

ABSTRACT This work presents a step‐by‐step approach for replacing Si‐IGBTs with SiC‐MOSFETs modules in a 9‐kW commercial double‐conversion UPS. Incremental modifications are applied to the original system, considering variations in switching frequency and evaluating its influence on losses and total volume. Through the use of Si‐IGBT transistors and redesigning the system, the volume and losses are analyzed for switching frequencies between 10 and 17 kHz. The IGBT showed limitations around 17 kHz, with high losses due to tail current. With SiC‐MOSFETs, the switching frequency is increased, resulting in smaller filter volumes. The SiC module allowed operation at frequencies in the tens and hundreds of kHz, with relatively low switching losses, which significantly reduced the volume of filters and heat transfer systems. These technological advancements resulted in reductions of up to 78% in the total volume and improved efficiency, enabling operation at lower temperatures and potentially increasing the lifetime of components. [ABSTRACT FROM AUTHOR]

Ellipticity has a significant impact on the flow and heat transfer performance of microchannel heat exchangers (MHEs) with elliptical concave cavities. In this study, five types of MHEs with different elliptical concave cavities (ellipticities of 0.4, 0.6, 0.8, 1.0, and 1.2) were designed. The influence of ellipticity on the flow and heat transfer performance of MHEs was numerically investigated using ANSYS Fluent 21.0 R1. Moreover, MHEs with corresponding elliptical concave cavities structures were processed and manufactured, and then an experimental platform was designed and built for experimental verification. The results showed that the fluid velocity distribution in MHEs with elliptical concave cavities was symmetrical, and the formation of secondary flow in the elliptical concave cavities led to the continuous destruction and reconstruction of the flow and thermal boundary layer in the microchannel, which is conducive to mass and heat transfer in the MHEs with elliptical concave cavities. The inlet and outlet pressure drop of MHEs with elliptical concave cavities increased as the inlet flow rate increased. At the same inlet flow rate, the inlet and outlet pressure drop of the MHE with elliptical concave cavities first increased and then decreased with increasing ellipticity. At an ellipticity of 1.0, the inlet and outlet of MHE exhibited the lowest pressure drop indicating that the MHE with an ellipticity of 1.0 featured the highest pressure drop performance. The cold‐water outlet temperature of the MHEs with elliptical concave cavities first decreased and then increased as the inlet flow rate increased. At the same inlet flow rate, the cold‐water outlet temperature of the MHEs with elliptical concave cavities first increased and then decreased with increasing ellipticity, while the hot‐water outlet temperature of the MHEs first decreased and then increased with increasing flow rate. This indicated that the MHE with an ellipticity of 1.0 exhibited excellent heat transfer performance. [ABSTRACT FROM AUTHOR]

The recent miniaturisation of implantable temperature recording tags has made measuring the water temperatures fish experience in the wild possible, but there may be a body size‐dependent delay in implanted tag response time to changes in external temperature. To determine whether fish body size affects the response rate of implanted temperature tags, we implanted 20 Salvelinus fontinalis (127–228 mm fork length (FL), 15.1–120.4 g) with temperature recording tags and subjected them to rapid temperature changes (±8°C in less than 2 seconds) in the laboratory. We found that thermal transfer rates, and the lag in temperature tag response rate, was positively correlated with fish size, but the direction of temperature change (colder or warmer) had no significant effect. In fish exposed to a slower rate of temperature change (2°C h−1) implanted tags did not show a response lag. Understanding the limitations of this important technology is crucial to determining the utility of the data it produces and its ability to accurately measure fish thermal experience in the wild. [ABSTRACT FROM AUTHOR]

In this experimental research, a single‐pass solar air heater comprising a porous curved channel is investigated to reveal the scope of high thermal performance during the winter season. The investigation explores the geometrical parameters for the porous channel maintained by using steel wiremesh layers of wire diameter of 0.45 mm and pitch of 2.35 mm, and the number of layers ranging from 3 to 12, which presents the channel porosity, ϕ$$ \phi $$, from 99% to 96%, respectively. The curved porous channel offers additional fluid mixing, thermal backup, and high heat transfer area, thereby increasing the convective heat transfer to the air and consequently the thermal performance. A series of experiments were carried out under real outdoor conditions to examine the various factors such as variable channel porosity, air flow rate, and the amount of solar energy received. The findings revealed that the curved porous channel with a channel porosity of 96% results in the maximum thermal and thermohydraulic efficiencies of about 85% and 79%, respectively, and the outlet air temperature of 79°C. [ABSTRACT FROM AUTHOR]