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Glioblastoma multiforme (GBM) is the most severe form of brain cancer in adults, characterized by its complex vascular network that contributes to resistance to conventional therapies. Thermal therapies, such as magnetic hyperthermia (MHT), emerge as promising alternatives, using heat to selectively target tumor cells while minimizing damage to healthy tissues. The organ-on-a-chip can replicate this complex vascular network of GBM, allowing for detailed investigations of heat dissipation in MHT, while computational simulations refine treatment parameters. In this in silico study, tumor-on-a-chip models were used to optimize MHT therapy by comparing heat dissipation in normal and abnormal vascular networks, considering geometries, flow rates, and concentrations of magnetic nanoparticles (MNPs). In the high vascular complexity model, the maximum velocity was 19 times lower than in the normal vasculature model and 4 times lower than in the low-complexity tumor model, highlighting the influence of vascular complexity on velocity and temperature distribution. The MHT simulation showed greater heat intensity in the central region, with a flow rate of 1 µL/min and 0.5 mg/mL of MNPs being the best conditions to achieve the therapeutic temperature. The complex vasculature model had the lowest heat dissipation, reaching 44.15 °C, compared to 42.01 °C in the low-complexity model and 37.80 °C in the normal model. These results show that greater vascular complexity improves heat retention, making it essential to consider this heterogeneity to optimize MHT treatment. Therefore, for an efficient MHT process, it is necessary to simulate ideal blood flow and MNP conditions to ensure heat retention at the tumor site, considering its irregular vascularization and heat dissipation for effective destruction. [ABSTRACT FROM AUTHOR]

The rapid progression in the current economic cities and the push for societal advancement are driving the development of tall, slim structures that require underground utility tunnels. These tunnels, known as underground services tunnels, are built beneath urban areas and house a variety of main pipelines for gas, heating, and electricity. They serve as underground walkways, high-voltage lines, drainage systems, and water supply networks. The construction of these underground tunnels is essential for facilitating the future growth of buildings and infrastructure without disrupting the streets where utilities were traditionally located in older city layouts. The increase of the quantity of deeply buried extra-long tunnels has increased quickly, leading to geothermal hazards emerging as a significant issue in engineering projects. This research has studied many approaches for ventilation or cooling of underground cable tunnels. Approximately 90% of the utilized techniques consisted of air ventilation, encompassing mechanical, natural, or a combination of both approaches. It is important to consider that this particular method is more commonly employed in regions with higher weather conditions similar to Egypt. Nonetheless, this approach efficiently sustains satisfactory indoor temperatures surrounding cables, guaranteeing that they stay below 40 °C. Nevertheless, in the particular climate region of Egypt, where outdoor temperatures can soar more to 40 °C, it became crucial to subject the air to cooling before it is supplied into the tunnel. The impact of the mist (FOG) system on tunnel cooling was also examined. However, it has been discovered that the humidity levels in tunnels rise excessively, despite the high initial cost involved, particularly in lengthy tunnels. Consequently, it is not regarded as a viable method for cooling cables. Its sole application lies in serving as a fire suppression system for cable tunnels. Approximately 10% of the conducted research employed water cooling, which involved circulating cold water through pipes located next to the cables in rows. As a result of convection heat transfer, the air surrounding the cables in the tunnel is effectively cooled. It was found from this study that mechanical air cooling (ventilation) is the most efficient way of dealing with heat dissipated from cables by convection inside tunnels. [ABSTRACT FROM AUTHOR]

The thermal safety of lithium-ion batteries has garnered significant attention due to its pivotal role in the field of new energy. In this work, a three-dimensional electrochemical-thermal coupling model based on the P2D model was established for predicting the thermal performance. The charge-discharge and temperature rise experiments via 18650 cylindrical Li[Ni0.6Co0.2Mn0.2]O2 / graphite batteries are designed to confirm the rationality of the model. The simulation results show that the highest temperature of the battery surface during discharging at 1 C and 4 C are 42.85 °C and 61.25 °C, and the experimental results are 42.50 °C and 62.85 °C, respectively. The electrode heat generation mainly comes from the reaction heat of cathode and anode during 1 C charge process, the maximum power is 1.2 W and 0.6 W, respectively. In the discharge process, the cathode dominates the reaction contribution of 1.02 W and the reaction heat power from the anode is only 0.016 W. The capacity of heat dissipation can be increased by enhancing the convective heat transfer coefficient and air velocity within a reasonable range. The proposed electrochemical-thermal coupling model is valuable to evaluate the heat behavior and promote the battery development. [ABSTRACT FROM AUTHOR]

Interfacial thermal resistance is crucial for determining the thermal conductivity of composites. Existing studies have explored hybrid filler systems and surface modification of alumina (Al2O3) particles for enhancing the thermal conductivities of polymer composites. In this study, highly acidic Al2O3 fillers were fabricated by modifying the raw Al2O3 surface using citric acid and glucose; the modified Al2O3 infiltrated an uncured epoxy adhesive at a concentration of 80 wt.%. The measured thermal conductivities of composites were up to 19.4% and 35.9% higher in glucose-filled and citric acid-filled Al2O3, respectively, compared with the raw Al2O3 at 25 °C. The experimental analysis and theoretical calculations revealed that the polar functionality on the surface facilitated hydrogen bonding between the filler and epoxy resin, which reduced the interfacial thermal resistance in the composite; this effect was the highest for the carboxyl group. To demonstrate the practical application of the modification technique, the exothermic performance test was conducted and indicated that a light-emitting diode lamp incorporating the citric acid filler-based composite exhibited excellent heat management performance compared to the raw Al2O3-applied composite. [ABSTRACT FROM AUTHOR]

The Camellia oleifera fruit harvester, a specialized agricultural device, is engineered for efficient operation within the densely planted C. oleifera groves of China's undulating terrains. Its design features a notably small footprint to navigate the constrained spaces between trees. With the enhancement of the functionality and power of the harvester, the engine compartment becomes even more congested. This, while beneficial for performance, complicates heat dissipation and reduces harvesting efficiency. In this study, experiments were initially conducted to collect temperature data from the main heat-generating components and parts susceptible to high temperatures within the harvester's engine compartment. Subsequently, a 3D model was developed for numerical simulations, leading to the proposal of optimization schemes for the engine compartment's structure and the validation of these schemes' feasibility. A comparison of the experimental data, both before and after optimization, revealed a significant reduction in the surface temperatures of components within the engine compartment following optimization. As a result, the heat dissipation of the engine compartment has been greatly optimized. The harvester has demonstrated prolonged normal operation, enhancing the reliability and economy of the harvester. [ABSTRACT FROM AUTHOR]

The ongoing push for miniaturization and increased computational power in electronic devices has intensified thermal management challenges, especially in harsh environments with extreme heat, moisture, vapour, dust, and vibration. This paper provides a comprehensive analysis of both direct and indirect cooling methods, focusing on heat transfer efficiency, optimization techniques, and practical applications. It emphasizes the critical importance of thermal management for maintaining the performance, reliability, and durability of electronic systems under tough conditions. The review explores advanced materials and cooling technologies, including the role of Thermal Interface Materials (TIMs) in prolonging the lifespan of Integrated Circuits (ICs) and the use of Phase Change Materials (PCMs) in substrate boards for versatile thermal management. It also discusses the effectiveness of Liquid Cold Plates for battery module thermal management and the potential of micro-channel liquid cooling systems in Switching Mode Power Supplies (SMPS) boards. By offering detailed insights into thermal design principles, the paper guides engineers in optimizing IC chip placement and improving system reliability. Additionally, it examines the evolution of traditional cooling methods, the rise of innovative techniques like thermoelectric cooling, and the impact of advancements in materials, design, and manufacturing on energy efficiency and environmental sustainability. The review highlights promising research areas and emerging technologies, contributing to the development of more efficient, reliable, and eco-friendly cooling solutions for extreme environments. [ABSTRACT FROM AUTHOR]

Heat sinks are used as heat exchangers to dissipate heat from electronic equipment due to their high functionality and viability. However, heat dispersion is the main obstacle to improving the heat sinks thermal efficiency. This paper has two main parts. The first part of this study focuses on the thermal design of the heat sink, encompassing several factors such as heat dissipation devices using natural convection, heat sinks with various geometries, locations of intake and outlet, materials of the core, flat fins (especially FPFHS and PFHS fins), and porosity fins. Heat sinks that are single-layered or multi-layered and heat sinks that use different cooling liquids. The second part examines interior heat transmission by investigating various indoor geometries, including cylindrical, circular, rectangular, and hexagonal shapes, and assessing their effect on the transport of heat. Additionally, interior structures influence various fin arrangements for any type of heat convection, including actual trials conducted on enclosures using diverse fin designs, are considered. The current study aims to collect research literature that studies the heat sink and various enclosures. The research has been divided into groups to simplify the research process for activities that use cavitation-based technology to improve heat transfer for heat sinks, especially heat exchangers used to cool electrical equipment. These advantages can be attributed to their outstanding features, which include ease of production, cost-effectiveness, and effective heat dissipation. [ABSTRACT FROM AUTHOR]

Since heat generation in electronic devices causes thermal failure, heat dissipation is of critical importance. Furthermore, deformable devices are subjected to mechanical stress, therefore, mechanically stable thermal management material should be considered. Herein, a strategy for printable, thermally conductive, and mechanically stable composite ink for thermal management is introduced. Based on the galvanic replacement between eutectic gallium indium (EGaIn) nanoparticles and silver (Ag) flakes, decoration of the EGaIn nanoparticles on Ag flakes is resulted from the difference in standard reduction potential between Ag, Ga, and In. The resultant alloy formation(Ag–Ga or Ag–In) serves as the thermal transport junction between Ag flakes, leading to high thermal and electrical conductivity (≈140 W mK−1 and ≈106 S m−1, respectively). In addition, owing to the polymer binder, the printed ink is mechanically stable on a substrate exhibiting stable thermal conductivity and sheet resistance under the cyclic bending test. Notably, the heat dissipation of the light‐emitting diode (LED) showed better performance when applied with the developed composite ink compared to commercial Ag paste and thermal paste. The junction temperature of the LED is reduced effectively, resulting in a longer lifetime of the LED. The thermal management solution can be utilized in next‐generation soft electronics. [ABSTRACT FROM AUTHOR]

This paper proposes a topology optimization formulation for additive manufacturing, in which the part, supports and their machining directions are simultaneously optimized. The part and supports are represented by two groups of density fields. The support structures are optimized for heat dissipation efficiency by solving a pseudo heat conduction problem under heat flux boundary loading and constraining the maximum temperature. The temperature constraint allows us to obtain self-supporting overhangs or non-self-supporting overhangs with support structures underneath. During the optimization, the support structures are further filtered by the solution fields from the advection-diffusion equations to ensure their accessibility to the machining tools. Based on the developed formulation, the optimized support structures would be distributed in the machinable regions of the part to enhance heat transfer in the manufacturing process. The unmachinable regions of the part, including enclosed voids, are self-supported for additive manufacturing. The sensitivity of the manufacturing constraint with respect to the design variables of the part, supports and the machining directions is derived through the adjoint method. We validate the effectiveness of the proposed formulation through several examples in 2D and 3D cases. [ABSTRACT FROM AUTHOR]

Copyright of Micronanoelectronic Technology is the property of Micronanoelectronic Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Refrigeration is the property of Journal of Refrigeration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heat dissipation significantly limits semiconductor component performance improvement. Thermal management devices are pivotal for electronic chip heat dissipation, with the enhanced thermal conductivity of materials being crucial for their effectiveness. This study focuses on single-crystal diamond, renowned for its exceptional natural thermal conductivity, investigating diamond microchannels using finite element simulations. Initially, a validated mathematical model for microchannel flow heat transfer was established. Subsequently, the heat dissipation performance of typical microchannel materials was analyzed, highlighting the diamond's impact. This study also explores diamond microchannel topologies under high-power conditions, revealing unmatched advantages in ultra-high heat flux density dissipation. At 800 W/cm2 and inlet flow rates of 0.4–1 m/s, diamond microchannels exhibit lower maximum temperatures compared to pure copper microchannels by 7.0, 7.2, 7.4, and 7.5 °C, respectively. Rectangular cross-section microchannels demonstrate superior heat dissipation, considering diamond processing costs. The exploration of angular structures with varying parameters shows significant temperature reductions with increasing complexity, such as a 2.4 °C drop at i = 4. The analysis of shape parameter ki indicates optimal heat dissipation performance at ki = 1.1. This research offers crucial insights for developing and optimizing diamond microchannel devices under ultra-high-heat-flux-density conditions, guiding future advancements in thermal management technology. [ABSTRACT FROM AUTHOR]

The high-power laser diode (HPLD) has witnessed increasing application in space, as the aerospace industry is developing rapidly. To cope with the space environment, optimizing the heat-dissipation structure and improving the heat-dissipation ability via heat conduction have become key to researching the thermal reliability of the HPLD in space environments. Based on a theoretical analysis of the HPLD, a simulation model of the HPLD was constructed for numerical simulation, and it was found that the maximum temperature and thermal resistance of lasers were efficaciously decreased by changing the packaging position of laser bars. The packaging position of the bars and the cutting angle of the microchannel heat sink (MCHS) were determined based on the light-emitting angle of the light-emitting unit and the internal structure of the MCHS. The internal structure of the MCHS was optimized through a single-factor experiment, an orthogonal experiment, and the combination of neural networks and genetic algorithms (GAs), using three key structural parameters, namely the MCHS ridge width, W1, the channel width, W2, and the channel length, L1. After optimization, the performance of the MCHS was obviously improved. Finally, an analysis was carried out on the applicability of the optimized MCHS to bars with a higher power. [ABSTRACT FROM AUTHOR]

We intend to analyze the influences of heat dissipation and heat generation on steady nanofluid stagnated flow along an extending surface along with thermal boundary layers. Water-based Cu and Al2O3 nanoparticles are considered. Moreover, the mechanism of injection/suction has been analyzed for such flows. Fundamental governing equations for the flow of an isotropic in-compressible thermally radiative single-phase nanofluid are defined by the set of nonlinear Partial Differential Equations (PDEs) which are transmuted to Ordinary Differential Equation (ODEs) and dealt with numerically by using Runge–Kutta (RK) fourth-order adopting shooting technique that gives approximate simulations. The numerical findings are illustrated as graphical and tabular representations after a careful parametric examination of determined parameters is carried out. The current outcomes specify that the velocity profiles decrease under the influence of magnetic strength while heat distribution positively changes under the effect of magnetic strength, heat source, radiative term and Biot number quantity. The temperature profiles behave negatively with the thermal Grashof number and Prandtl number. Moreover, the comparative simulations of the ongoing study with existing the literature for ensuing the obtained simulations have been worked out. [ABSTRACT FROM AUTHOR]

Thermal management of nanoscale quantum dots (QDs) in light-emitting devices is a long-lasting challenge. The existing heat transfer reinforcement solutions for QDs-polymer composite mainly rely on thermal-conductive fillers. However, this strategy failed to deliver the QDs’ heat generation across a long distance, and the accumulated heat still causes considerable temperature rise of QDs-polymer composite, which eventually menaces the performance and reliability of light-emitting devices. Inspired by the radially aligned fruit fibers in oranges, we proposed to eliminate this heat dissipation challenge by establishing long-range ordered heat transfer pathways within the QDs-polymer composite. Ultrahigh molecular weight polyethylene fibers (UPEF) were radially aligned throughout the polymer matrix, thus facilitating massive efficient heat dissipation of the QDs. Under a UPEF filling fraction of 24.46 vol%, the in-plane thermal conductivity of QDs-radially aligned UPEF composite (QDs-RAPE) could reach 10.45 W m−1 K−1, which is the highest value of QDs-polymer composite reported so far. As a proof of concept, the QDs’ working temperature can be reduced by 342.5 °C when illuminated by a highly concentrated laser diode (LD) under driving current of 1000 mA, thus improving their optical performance. This work may pave a new way for next generation high-power QDs lighting applications.

This research focuses on the development and simulation analysis of heat-dissipating fins made of copper, integrated into photovoltaic panels, with the aim of mitigating temperature increases during operation. This initiative arises from evidence that solar panels experience a reduction in energy efficiency when operating at temperatures higher than standard test conditions. The photovoltaic panel was simulated both without fins and with fins under standard test conditions and extreme conditions. The simulation consists of the following steps: design, meshing, selection of physical models and materials, assignment of boundary conditions, validation of the simulation, and interpretation of the results. During validation, results obtained via simulation were compared experimentally, yielding a mean absolute percentage error of 0.28%. It was concluded that the fins with the greatest heat dissipation relative to their area are those of 40 mm height; with this height, the temperature of the photovoltaic panel is reduced by 2.64 K, which represents an efficiency increase of 1.32%. Furthermore, it was concluded from the analyzed data that the efficiency of the fins increases at high temperatures.

The paper examines solution for a two-dimensional steady, viscous, heat dissipation, incompressible hydro-magnetic free convective flow past a uniformly moving vertical porous plate immersed in a porous material in the presence of the Soret effect, Dofour effect and Chemical reaction. A constant magnetic field is directed into the fluid area perpendicular to the plate. The MATLAB built-in bvp4c solver approach is used to solve the governing non-dimensional equations. The discussion of the current issue focuses mostly on the impacts of thermal diffusion, magnetic field, thermal radiation, Grashof number, Soret number, Dufour number, and chemical reaction. It is observed that the Soret number improves fluid temperature. In addition, the fluid's temperature, concentration, and velocity all drop as the magnetic field parameter rises. Although the heat dissipation caused by the medium's porosity is usually disregarded in convective MHD flow simulations, it is considered in this work.

Thermal boundary conditions of the turbine disk cavity system are of great importance in the design of secondary air systems in aero-engines. This study aims to investigate the complex heat transfer mechanisms of a rotating turbine disk under high-speed conditions. A high-speed rotating free-disk model with Dorfman empirical solutions is developed to evaluate the heat transfer performance considering various factors. Specifically, the influence of compressibility, variable properties, and heat dissipation is determined using theoretical and numerical analyses. In particular, a novel combined solution method is proposed to simplify the complex heat transfer problem. The results indicate that the heat transfer performance of a free disk is primarily influenced by the rotating Mach number, rotating Reynolds number, Rossby number, and wall temperature ratio. The heat transfer temperature and Nusselt number of the free disk are strongly correlated with the rotating Mach number and rotating Reynolds number. Analysis reveals that heat dissipation is a critical factor affecting the accurate evaluation of the heat transfer performance of the turbine disk. Thus, the combined solution method can serve as a reference for future investigations of flow and heat transfer in high-speed rotating turbine disk cavity systems in aero-engines.

The continued miniaturization of chips demands highly thermally conductive materials and effective thermal management strategies. Particularly, the high‐field transport of the devices built with 2D materials is limited by self‐heating. Here a systematic control of heat flow in single‐side fluorinated graphene (FG) with varying degrees of fluorination is reported, revealing a superior room‐temperature thermal conductivity as high as 128 W m−1 K−1. Monolayer graphene/FG lateral heterostructures with seamless junctions are approached for device fabrication. Efficient in‐plane heat removal paths from graphene channel to side FG are created, contributing significant reduction of the channel peak temperature and improvement in the current‐carrying capability and power density. Molecular dynamics simulations indicate that the interfacial thermal conductance of the heterostructure is facilitated by the high degree of overlap in the phonon vibrational spectra. The findings offer novel design insights for efficient heat dissipation in micro‐ and nanoelectronic devices. [ABSTRACT FROM AUTHOR]

Commercial thermally conductive dielectric materials used in electronic packaging typically exhibit thermal conductivities (κ) ranging from 0.8 to 4.2 W m−1 K−1. Hexagonal boron nitride (h‐BN) flakes are promising thermally conductive materials for the thermal management of next‐generation electronics. These electrically insulating yet thermally conducting h‐BN flakes can be incorporated as thermal fillers to impart high κ to polymer‐based composites. A cellulose‐based composite embedded with few‐layer h‐BN (FLh‐BN) flakes, achieving a κ ≈ 21.7 W m−1 K−1, prepared using a cost‐effective and scalable procedure is demonstrated. This value is >5 times higher than the κ observed in composites embedded with bulk h‐BN (Bh‐BN, κ ≈ 4.5 W m−1 K−1), indicating the benefits of the superior κ of FLh‐BN on the κ of h‐BN polymer composites. When applied as a paste for thermal interface material (TIM), the FLh‐BN composite can reduce the maximum temperature (Tmax) by 24.5 °C of a heating pad at a power density (h) of 2.48 W cm−2 compared to Bh‐BN composites at the same h‐BN loading. The results provide an effective approach to improve the κ of cellulose‐based thermal pastes for TIMs and demonstrate their viability for heat dissipation in integrated circuits (ICs) and high‐power electronic devices. [ABSTRACT FROM AUTHOR]

Copyright of Bearing is the property of Bearing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bearing is the property of Bearing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Automobile Technology is the property of Automobile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ultra-low Earth orbit (LEO) satellites are widely used in the military, remote sensing, scientific research, and other fields. The ultra-LEO satellite faces the harsh aerothermal environment, and the complex variable attitude task requires the radiator of the satellite to not only meet the heat dissipation requirements of the load but also to resist aerothermal flux. In this study, the aerothermal flux of 160–110 km was calculated, and the loop heat pipe (LHP) coupled with a thermo-electric cooler (TEC) and multi-layer insulation (MLI) were applied to ultra-LEO satellites to determine the variable switching and fast response of heat dissipation and heat protection. An aerothermal flux simulation test platform was built. After the assessment of the ultra-LEO aerothermal flux test, even when the head temperature was as high as 350 °C and the side radiator temperature was as high as 160 °C, the temperature of the internal heat source could be controlled within 22.5 °C through the efficient work of the thermal variable switch system. The study confirms the accuracy and feasibility of the system, which provides an important reference for the subsequent actual on-orbit mission. [ABSTRACT FROM AUTHOR]

The charging and discharging process of electric vehicle power batteries generates a large amount of heat, and the development of an efficient heat dissipation design is conducive to improving the efficiency and safety of the battery packs. A combination of cold plate and battery packs was used for the liquid cooling heat dissipation design of the battery packs. The critical maximum temperature was set to 50 ℃ here and the results showed that the average battery temperature was lowest and the temperature uniformity was better when the cold plate and battery packs were arranged in a side-to-side lateral direction. The minimum required mass flow rate was 0. 05 kg / s for the inter-phase lateral model, while the inter-phase upward model had the lowest pressure drop. Therefore, a structure with an interphase arrangement of power battery and cold plates can be preferred for the thermal design of the battery packs. [ABSTRACT FROM AUTHOR]

Low ionic conductivity, oxidation potential, and poor lithium stability limit the applications of solid polymer electrolyte (SPE) in advanced energy storage systems. Combining functional inorganic materials and flexible polymers is crucial for achieving high ionic conductivity and exceptional rate performance in all-solid-state batteries (ASSBs). Herein, uniform boron nitride nanosphere (BNSPH) with reactive surface defects was prepared through an improved chemical vapor deposition method with high-temperature ammonia immobilization treatment and was introduced to the poly-(ethylene oxide) (PEO)-based SPE. Homogeneously dispersed nanostructures reduce the polymer's crystallinity, facilitating the movement of polymer chain segments and significantly improving the composite electrolyte's ionic conductivity. The interaction between BNSPH and the PEO chain enhances the structural stability of the composite polymer electrolyte (CPE) under high voltage, and the oxygen vacancies on the BNSPH surface immobilize TFSI–, promoting the transfer of more dissociated Li+ through the PEO chain. In addition, the excellent thermal conductivity enhances the interface stability and effectively avoids the growth of lithium dendrites. The CPE-5% exhibits an ionic conductivity of 3.86 × 10–4 S cm–1 and high voltage stability at 60 °C. Therefore, the assembled Li|CPE-5%|Li cell exhibited stable plating/stripping for 2000 h with a small polarization voltage. Furthermore, Li/LFP batteries incorporating CPE-5% exhibit remarkable rate performance (87.8 mA h g–1 at 2.0 C) and outstanding cycle stability (157.4 mA h g–1 after 150 cycles at 0.5 C and 60 °C). Furthermore, the NCM622/Li assembled with CPE-5% could achieve an excellent lifespan. This study confirms the feasibility of this application and inspire the application of defect-rich BNSPH in SPEs. [ABSTRACT FROM AUTHOR]

Electronic cooling is crucial for modern electronic device design, ensuring devices operate at peak performance, reliability, and longevity. This paper offers an in-depth critical review of electronic cooling technologies, covering both established methods and recent innovations. It explores the challenges in electronic cooling, such as effective heat dissipation, thermal management, and reliability concerns. Various cooling strategies are examined, including air cooling, liquid cooling, phase-change cooling, and emerging technologies like thermoelectric cooling and two-phase immersion cooling. The paper also evaluates recent advancements in materials, design, and manufacturing processes that have transformed electronic cooling. Additionally, it discusses the impact of electronic cooling on energy efficiency, environmental sustainability, and cost-effectiveness. Finally, the review highlights future research directions and opportunities for innovation in electronic cooling to meet the increasing demands of high-performance electronic systems. The findings provide valuable insights for thermal design engineers, assisting in optimal IC chip placement on the substrate board to enhance reliability and extend operational lifespan. [ABSTRACT FROM AUTHOR]

Laser‐driven white light exhibits exceptional brightness and directionality, making it particularly well‐suited for spotlight applications. Yet, attaining high‐quality white light remains challenging due to the sluggish heat dispersion and inconsistent light uniformity of color converters. In this study, an innovative phosphor‐in‐glass (PiG) film architecture is introduced, aiming to achieve superior quality laser‐driven light, where the traditional Y3(Ga,Al)5O12:Ce3+ (YAGG:Ce3+) PiG film is topped with a Al2O3‐in‐glass (AiG) film. The heightened thermal conductivity of the AiG film facilitates quicker dissipation of heat, consequently elevating the luminescence saturation threshold from 14 to 16 W mm−2 and luminous flux from 1243.8 to 1475.9 lm. The increased light scattering attributed to the AiG film also effectively disperses both laser and emitted light, significantly enhancing the angular consistency of color rendering index (Ra). This improvement is evident as the coefficient of variation (Cv) decreases dramatically from 16.69% to 0.25%. Moreover, by integrating CaAlSiN3:Eu2+ (CASN:Eu2+) into the PiG film and fine‐tuning the YAGG:Ce3+ and CASN:Eu2+ ratio, a high‐quality laser‐driven white light achieving an impressive color rendering index (Ra) of 88.7 and offering an adjustable correlated color temperature (CCT) has been developed. This innovation holds tremendous potential as a versatile spotlight solution for both indoor and outdoor settings. [ABSTRACT FROM AUTHOR]

The heat dissipation capacity prediction and cooling adjustment of the space station are rarely reported and are currently very urgent. Therefore, this paper does the following work. First, a twin system equivalent to the actual thermal system is built based on the digital twin technology, and the net heat dissipation capacity that can reflect the energy storage characteristics of the radiator and the total heat that can reflect the load changes in the cabin are identified. Then, the optimum operating state of the thermal system is planned by using the changing characteristics of the two, to predict the maximum heat dissipation capacity and heat dissipation margin of the space station. Finally, the cooling adjustment method is given. The results show that the heat dissipation capacity of the shadow area of the space station is about 16kW, which is about 1.5 times the sunlit area. The series control reduces the time difference between hot and cold source from 677 s to about 77 s. The radiator absorptivity is only increased by 0.15, and its accumulated heat dissipation will be reduced by 7.48 kWh in one orbital period. The radiator emissivity decreased by 0.05, and the accumulated heat dissipation decreased by 1.6 kWh. When the solar azimuth is 20° and 160°, the heat dissipation capacity ratio of the whole module in the sunlit zone is about 0.9 of a single orbital period. It is worth mentioning that the idea of heat dissipation capacity prediction and cooling adjustment proposed in this paper has important reference significance for both fluid network and non-fluid network structures. [ABSTRACT FROM AUTHOR]

This research focuses on the development and simulation analysis of heat-dissipating fins made of copper, integrated into photovoltaic panels, with the aim of mitigating temperature increases during operation. This initiative arises from evidence that solar panels experience a reduction in energy efficiency when operating at temperatures higher than standard test conditions. The photovoltaic panel was simulated both without fins and with fins under standard test conditions and extreme conditions. The simulation consists of the following steps: design, meshing, selection of physical models and materials, assignment of boundary conditions, validation of the simulation, and interpretation of the results. During validation, results obtained via simulation were compared experimentally, yielding a mean absolute percentage error of 0.28%. It was concluded that the fins with the greatest heat dissipation relative to their area are those of 40 mm height; with this height, the temperature of the photovoltaic panel is reduced by 2.64 K, which represents an efficiency increase of 1.32%. Furthermore, it was concluded from the analyzed data that the efficiency of the fins increases at high temperatures. [ABSTRACT FROM AUTHOR]

To overcome the overheating phenomena of electronic devices and energy components, developing advanced energy‐free cooling coatings with promising radiative property seem an effective and energy‐saving way. However, the further application of these coatings is greatly limited by their sustainability because of their fragile and easy contamination. Herein, it is reported that a bioinspired radiative cooling coating (BRCC) displayed sustainably efficient heat dissipation by the combination of high emittance and robust self‐cleaning property. With the hierarchical porous structure constructed by multiwalled carbon nanotubes (MWCNTs), modified SiO2 and fluorosilicone (FSi) resin, the involvement of the BRCC improves the cooling performance by increasing ≈25% total heat transfer coefficient. During the abrasion and soiling tests, the BRCC‐coated Al alloy heat sink always displays stable radiative cooling performance. Moreover, the simulation and experimental results both revealed that reducing surface coverage of BRCC (≈80.9%) can still keep highly cooling efficiency, leading to a cost‐effective avenue. Therefore, this study may guide the design and fabrication of advanced radiative cooling coating. [ABSTRACT FROM AUTHOR]

The demand for lightweight and cost-effective heat sinks is increasing. A typical method for economically manufacturing complex-shape heat sinks is die casting. To reduce the weight of the die-cast heat sinks, thinning the fins and base is common practice. We experimented with casting heat sinks using Al-25%Si in a conventional die casting machine with the aim of economically producing thinner fins and bases. Compared with the aluminum alloy used in conventional die casting, Al-25%Si has superior fluidity, which is proven to be very useful for reducing the thickness of the fins and base. As a result, we successfully reduced the heat sink weight using Al-25%Si and a conventional die casting machine. To investigate the properties of the produced Al-25%Si thin fin heat sink, we compared the effects of fin thickness, fin height, number of fins, and base thickness on heat dissipation and weight reduction. Additionally, we compared the weight and heat dissipation properties with those of a commercial heat sink and found that our Al-25%Si heat sink maintains the same heat dissipation performance but for 35% lower weight. [ABSTRACT FROM AUTHOR]

Aviation-integrated communication equipment is integral to modern aircraft to ensure its performance and safety. The heat dissipation problems of equipment have become increasingly prominent for the high electronic integration and system power consumption. To solve the above problem, the heat dissipation performance of aviation-integrated communication equipment based on graphene films is deeply studied. This paper establishes a three-dimensional model of aviation-integrated communication equipment to simulate the distribution of temperature fields. The influence between aluminum alloy and graphene films on the surface of magnesium alloy on the heat dissipation performance of aviation-integrated communication equipment is studied. The simulation results show that the heat balance time of the equipment using graphene films on the surface of magnesium alloy is reduced from 3600 s to 800 s, representing an approximately 77.78% improvement; the measured equipment exhibited a reduction in its overall thermal equilibrium temperature, decreasing from 68.1 °C to 66.3 °C, representing an improvement of approximately 2.64%. [ABSTRACT FROM AUTHOR]

High heat flow density electronic components need cooling plates with strong heat exchange capacity to maintain temperature balance. To obtain better cooling performance, four different flow channel types of cooling plates are designed, including an S-type channel, Z-type channel, mosaic channel and double-layer channel. The maximum temperature of the cooling plate, outlet temperature and pressure drop under different working conditions and coolant are analyzed by numerical simulation. The simulation results show that the double-layer channel design can effectively enhance the heat transfer effect of the cooling plate and reduce the pressure drop. The maximum temperature of the cooling plate of the double-layer flow channel is 6.88 °C lower than that of the Z-type flow channel. Moreover, increasing the inlet flow rate and lowering the coolant inlet temperature can improve the cooling performance of the cold plate, but increasing the inlet flow rate will lead to an increase in the pressure loss of the cold plate. When the coolant of the double- layer channel cooling plate is 20% ethylene glycol-water solution, the cooling performance is better than the other three coolants. Other channel cooling plates perform better with water as the coolant. [ABSTRACT FROM AUTHOR]

Light-emitting diode (LED) lighting has been increasingly prominent in the global market in recent years, due to the high luminous efficiency. Generally, the integrated LEDs products can inevitably generate a lot of heat, leading to the extremely high local temperature. However, LED cooling heat pipes in practical applications often face some challenges, such as insufficient contact thermal resistance and heat transfer area. In this study, a heat sink was designed to transfer the heat inside the LED out in time for the long life of the products. Micro heat pipe array (MPHA) was used to explore the impact of the structure on heat dissipation performance using computational fluid dynamics (CFD) software. Two models were established to compare with the experiment. The results show that the maximum error between the simulated and experimental values reached 39.62% at 0.5 m/s. Among them, the simulated value under forced convection was in good agreement with the experimental value, with the maximum error of 11.85%, indicating the accurate simulation. The heat dissipation of LEDs was varied greatly under the action of heat sinks with different structures. Moreover, the better uniformity of temperature was achieved in the U-shaped flat-plate micro heat pipe. Furthermore, the maximum difference of temperature was only 0.6℃ for the MHPA in the vertical direction at an input power of 50W. The better uniformity of temperature was promoted the expansion of the heat exchange area, thus improving the heat transfer capacity of MHPA. The radiator was optimized to enhance the convective heat transfer rather than the heat dissipation. The verified model was used to simulate and analyze the five influencing factors (fin type, inlet wind speed, fin height and fin spacing) on the heat dissipation of LED heat sources. Research results show that the saw-shaped fins shared the larger area of effective heat conduction and better heat dissipation, compared with the traditional straight fins and W-fins. The better performance and heat transfer were achieved under 0.5 m/s or 3 m/s conditions. The convective heat transfer also increased, as the inlet wind speed increased. The heat dissipation under 3m/s conditions was much better than 0.5 m/s. However, the stable temperature drops of the LED heat source gradually slowed down, as the wind speed increased. The economic factors were considered in actual applications, such as the power consumption of the fan. It is necessary to select the wind speed the most suitable for the application scenario. Therefore, the smaller fin spacing and higher fin height of radiator structure can increase the effective heat transfer area and the heat dissipation performance of the heat sink. An orthogonal experiment was designed to determine the best working conditions and structure. The optimal combination was achieved in the forced convection and structure with an inlet wind speed of 3.5 m/s, a fin height of 12 mm and a spacing of 8 mm. The finding can provide new ideas to design the heat dissipation of lighting equipment for the service life and stability of LEDs. [ABSTRACT FROM AUTHOR]

This research aims to improve thermal performance and compare the performance of two common crystalline PV panel types (Mono and poly). Modules with a back-cooling system were designed and numerically analyzed with SolidWorks and ANSYS-Fluent-2021-R2 for the simulation under Baghdad weather at noon. The cooling system used consists of a phase-change material, paraffin wax (RT55), with a thickness of 5 cm and a heatsink with 33 fins with heights of 10, 20, and 30 mm and thicknesses of 2, 4, and 6 mm. to select the best height of the wax 1, 3, 5, 10, 20 cm examined. The result showed that for polycrystals, the panel temperature was reduced by 8.4°C using PCM and 11.9°C using PCM-fins. Also, output power was enhanced to 200.6 W by 10.2 W, and efficiency improved by 5%. Similarly, using PCM and PCM-fins lowered the temperature of the monocrystalline by 8.3 and 12.5°C, respectively. Therefore, the output power is enhanced to 202.4 W by 10.7 W and improves the electrical efficiency by 5.2%. The results of the study showed that mono had better performance than poly. This result is acceptable and is in good agreement with previous studies. [ABSTRACT FROM AUTHOR]

Liquid cooling is widely used on high power motors. Optimal design of the coolant loop could help rise the power density. The coolant channels are placed across the stator core in this research. The heat dissipation performances of the coolant channel with different designs are compared and analyzed through simulation. Experiments were carried out to verify the simulation results and the feasibility of the cooling method. The results show that the coolant loop should be placed tightly close to the slots. The heat dissipation performance of the optimized coolant loop is efficient compared to the jacket cooling design. The coolant channels across the stator core could remain sealed under a 0.5 Mpa pressure at least according to the air proof test. The coolant pressure within the channels could be reduced efficiently through increasing the parallel loop number or moving the channels away from the slots properly. The winding temperature of the measured values and the simulated results of the motor with jacket cooling is within 2 °C.

Microchannel heat sinks (MCHSs) are advanced cooling systems used in various applications such as electronics cooling, thermal management of high-power microprocessors, and microelectronic devices. These heat sinks are designed to efficiently dissipate heat generated by electronic components to maintain optimal operating temperatures and ensure device reliability. Employing appropriate fins within MCHSs is a crucial strategy to enhance heat removal efficiency. Since few investigations have been performed on the simultaneous thermo-hydraulic features in microchannels with Tesla valves, this research addresses this gap by suggesting that the microchannels of a heat sink be reinforced with novel Tesla valve-shaped fins. Tesla valves are designed to offer different levels of resistance depending on the flow direction. This characteristic allows for selective control of pressure drop and heat transfer efficiency by simply switching the flow direction. Utilizing Tesla valve-shaped fins is an almost new approach that differentiates the current research from conventional designs. The advantage of this structure is that under different circumstances, depending on whether more heat transfer is required or less pressure drop (ΔP), the flow direction can be changed, and the maximum efficiency of the MCHS can be accessed. The other innovative aspect of this study lies in the integration of artificial neural network (ANN) models to optimize the efficiency of MCHSs equipped with Tesla valve-shaped fins. The simulations were conducted to characterize the flow and thermal features of the MCHS. Then, these data were used as the benchmark for training the ANN models. Four ANN models were introduced to anticipate the Nusselt number (Nu) and ΔP in each forward and reverse direction. The divider's acute angle (α), the divider's obtuse angle (β), and the divider's radius (R) were selected as the input data. Multi-objective optimization and genetic algorithms were used to achieve the optimal conditions. In the optimal thermal design (Setting 2: MCHS with fin variables of α = 60 β = 180, and R = 80 μm in reverse flow direction), the overall performance had a significant enhancement of 57.1 % compared to the device lacking fins. Furthermore, in Setting 2, the overall performance of the MCHS and its diodicity experienced notable improvements of approximately 12.1 % and 38.5 %, respectively. Implementing the parameters of Setting 5 (MCHS with fin variables of α = 60, β = 152.32, and R = 73.10 μm in forward direction) during fin production resulted in a notable enhancement of about 41.1 % in the device's overall performance.

This study explores the design and optimization of thermomagnetic generators with a primary emphasis on enhancing energy efficiency. The core objectives revolve around improving power generation and efficient heat dissipation. We conducted an extensive investigation, systematically varying parameters such as dimensions, coil turns, and material properties, including temperatures and magnetization. At the heart of this research lies the utilization of the variable magnetic susceptibility of ferromagnetic–paramagnetic materials within distinct temperature zones. Gadolinium (Gd) was selected due to its unique Curie temperature (TC) closely aligned with room temperature. The Gd disk's motion serves a dual purpose—acting as a heat conveyor from source to sink and inducing voltages. The synergy between a copper wire coiled around the Gd disk and the magnetic field generated by a permanent magnet (PM) facilitates voltage induction. The dynamic motion of the Gd disk, driven by changes in net forces (permanent magnet force, gravity force, and spring force), powers this energy conversion process. This versatile technique holds promise across various applications, especially in scenarios characterized by significant waste heat, such as engines and solar panels. Our multifaceted optimization approach not only enhances our understanding of thermomagnetic generators but also underscores their potential as sustainable and efficient contributors to energy solutions. [ABSTRACT FROM AUTHOR]

The increasing demand for high‐performance devices on heat dissipation makes it approach the bottleneck even for metals with high thermal conductivities. The coating of only one layer of graphene, the heat dissipation performances of Cu, Ag, and Al can be further enhanced, e.g., with a maximum temperature reduction by ≈9% for a Cu foil is demonstrated. Molecular dynamics (MD) analysis of spectral phonon transmission reveals that low‐frequency phonons play a significant role in the thermal transport within the Cu/single‐layer graphene (SLG) system, and the high‐frequency phonons exhibit substantial mismatch. It suggests that the thermal anisotropy of graphene enables a rapid heat dispersion in the in‐plane direction and provides an effective thermal insulation in the out‐of‐plane direction. The thermal conductivity calculations demonstrate an enhanced participation of phonons in heat conduction by the graphene layer, indicating a novel heat conduction mechanism in the Cu/single‐layer graphene system. These findings highlight the positive impact of graphene on the heat conduction of metals, and they will hold crucial implications for the design and application of graphene‐based thermal devices is believed. [ABSTRACT FROM AUTHOR]

The paper examines solution for a two-dimensional steady, viscous, heat dissipation, incompressible hydro-magnetic free convective flow past a uniformly moving vertical porous plate immersed in a porous material in the presence of the Soret effect, Dofour effect and Chemical reaction. A constant magnetic field is directed into the fluid area perpendicular to the plate. The MATLAB built-in bvp4c solver approach is used to solve the governing non-dimensional equations. The discussion of the current issue focuses mostly on the impacts of thermal diffusion, magnetic field, thermal radiation, Grashof number, Soret number, Dufour number, and chemical reaction. It is observed that the Soret number improves fluid temperature. In addition, the fluid's temperature, concentration, and velocity all drop as the magnetic field parameter rises. Although the heat dissipation caused by the medium's porosity is usually disregarded in convective MHD flow simulations, it is considered in this work. [ABSTRACT FROM AUTHOR]

The six cylinder thermoregulatory model (SCTM) has been validated thoroughly for resting humans. This type of modeling is helpful to predict and develop guidance for safe performance of work and recreational activities. In the context of a warming global climate, updating the accuracy of the model for intense exercise in warm environments will help a wide range of individuals in athletic, recreational, and military settings. Three sets of previously collected data were used to determine SCTM accuracy. Dataset 1: two groups [large (LG) 91.5 kg and small (SM) 67.7 kg] of individuals performed 60 min of semirecumbent cycling in temperate conditions (25.1°C) at metabolic rates of 570–700 W. Dataset 2: two LG (100 kg) and SM (65.8 kg) groups performed 60 min of semirecumbent cycling in warm/hot environmental conditions (36.2°C) at metabolic rates of 590–680 W. Dataset 3: seven volunteers completed 8-km track trials (∼30 min) in cool (17°C) and warm (30°C) environments. The volunteers' metabolic rates were estimated to be 1,268 W and 1,166 W, respectively. For all datasets, SCTM-predicted core temperatures were found to be similar to the observed core temperatures. The root mean square deviations (RMSDs) ranged from 0.06 to 0.46°C with an average of 0.2°C deviation, which is less than the acceptance threshold of 0.5°C. Thus, the present validation shows that SCTM predicts core temperatures with acceptable accuracy during intense exercise in warm environments and successfully captures core temperature differences between large and small individuals. NEW & NOTEWORTHY: The SCTM has been validated thoroughly for resting humans in warm and cold environments and during water immersion. The present study further demonstrated that SCTM predicts core temperatures with acceptable accuracy during intense exercise up to 1,300 W in temperate and warm environments and captures core temperature differences between large and small individuals. SCTM is potentially useful to develop guidance for safe operation in athletic, military, and occupational settings during exposure to warm or hot environments. [ABSTRACT FROM AUTHOR]