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Solar evaporation attracted lots of attention due to its environment-friendly and high efficiency, which is a potential approach to collecting fresh water. Many efforts have been made to improve the evaporation rate in the open space. While the actual water collection rate is far less than the evaporation rate, especially in passive water collection, limiting its practical and scalable applications. In this review, we focus on freshwater collection based on solar evaporation. Firstly, heat and mass transfer behaviors on the evaporation side were summarized to improve evaporation performance, including heat transfer processes in thermal radiation, convection, and conduction; mass transfer processes in water supply, evaporation enthalpy, and salt rejection. Sequentially, subcooling, wettability, and geometry of the condensation side were discussed to improve water collection performance, which should be designed collaboratively with the evaporation side in a confined space. Finally, thermal recovery and electricity generation beyond water collection were also introduced, and some challenges still need to improve in the further for scalable and practical applications, including passive water collection rate, integrated system, and long-term issues. [ABSTRACT FROM AUTHOR]

Nanoporous graphene own high surface area and unique structural and physical properties due to nano-sized pores in graphene nanosheet. Nanoporous graphene has been modified by the introduction of surface functional groups, doping, or nanoparticle modification and applied for nanocomposites. The overview basically highlights design, properties, and potential of functionalized nanoporous graphene derived nanocomposites in advanced membranes (desalination/gas/oil separation), thermal management, electrocatalysts, and micro-supercapacitors. According to literature, pore size of neat nanoporous graphene is 3–11 Å and hydroxyl functional nanoporous graphene also had nanopore size of <10 Å. Functionalized nanoporous graphene revealed 100% salt rejection, while hydroxyl functional nanoporous graphene had 89% salt rejection due to altered surface properties. Both neat and functionalized nanoporous graphene has high gas permeance of ∼103–105 GPU towards separation CO2, CH4, N2, etc. Few attempts on micro-supercapacitor like molybdenum disulfide nanoporous graphene resulted in volumetric capacitance of 55 F cm−3 and capacitance retention of 82%. Forthcoming research on functionalized nanoporous graphene may overcome design/performance challenges leading to superior features and large-scale utilizations. [ABSTRACT FROM AUTHOR]

Electric vehicles, as a major strategy for climate change mitigation, uses lithium-ion batteries extensively as the power source. However, the operation, performance and lifetime of lithium-ion batteries depend on the battery temperature, which can have a wide range due to heat generation within the battery and significant variations in the ambient conditions due to changes in seasons and geographical locations where electric vehicles are operated. In the present study, thermal management methods/strategies on the capacity fade of lithium-ion batteries are assessed through a validated capacity fade model for lithium-ion batteries along with a thermal model for the heat generation in the battery and dissipation over battery surface, represented by various thermal management methods. The driving conditions are simulated through a constant and various standard drive cycles. It is shown that battery temperature has the predominant impact on the capacity fade, and it can be controlled through effective thermal management. A much more significant spread in battery capacity fade occurs with various thermal management methods for a lower initial battery temperature (20°C) compared to the higher temperatures (35°C and 50°C), hence, thermal management is much more effective in reducing capacity fade at battery temperatures close to 20°C, which is considered the optimum operating temperature for lithium-ion batteries. Further, the results indicate that using a lower charge voltage can result in slightly less capacity fade over cycling. Regenerative braking makes it more realistic to use lower charge voltages, since the battery can be recharged during operation, thereby increasing driving range, while preventing increased capacity fade. Effective thermal management is more imperative for realistic intense and aggressive driving behaviors. [ABSTRACT FROM AUTHOR]

Friction stir welding (FSW) offers significant advantages over fusion welding, particularly for high-strength alloys like Inconel 718. However, achieving optimal surface quality in Inconel 718 FSW remains challenging due to its sensitivity to temperature fluctuations during welding. This study integrates finite element simulations, statistical analysis, and advanced control methodologies to enhance weld surface quality through adequate thermal management. High-fidelity simulations of the FSW process were conducted using a validated 3D transient COMSOL Multiphysics model, producing a comprehensive dataset correlating process parameters (rotational speed, axial force, and welding speed) with workpiece temperature. This dataset facilitated statistical analysis and parameter optimization through Analysis of variance (ANOVA) method, leading to a deeper understanding of process variables. A nonlinear state-space system model was subsequently developed using experimental data and the system identification toolbox in Matlab, incorporating domain-specific insights. This model was rigorously validated with an independent dataset to ensure predictive accuracy. Utilizing the validated model, tailored control strategies, including proportional-integral-derivative (PID) and model predictive control (MPC) in both single and multivariable configurations, were designed and evaluated. These control strategies excelled in maintaining welding temperatures within optimal ranges, demonstrating robustness in response times and disturbance handling. This precision in thermal management is poised to significantly refine the FSW process, enhancing both surface integrity and microstructural uniformity. The strategic implementation of these controls is anticipated to substantially improve the quality and consistency of welding outcomes. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive numerical investigation into the thermal performance of solar collectors integrated with encapsulated phase change materials (PCMs) using a transient three-dimensional (3D) approach. The performance of two distinct PCMs—paraffin wax and RT60—was evaluated under varying operational conditions, including seasonal variations, inlet pipe velocities, and inlet temperatures. The results indicate that paraffin wax exhibits a higher peak temperature, reaching approximately 360 K, compared to RT60's peak of 345 K, making paraffin wax more effective for consistent thermal energy storage. Paraffin wax also maintained higher fluid fractions, with a maximum of 0.9 in summer, indicating superior heat absorption and retention capabilities. In contrast, RT60 demonstrated a quicker phase transition, fully liquefying at a lower fluid fraction, which is advantageous for rapid heat release. Seasonal variations significantly impacted system efficiency, with the highest efficiency observed in June at 365 K and the lowest in December at 340 K. The study also found that lower inlet velocities (e.g., 0.25 L/s) significantly improved heat retention, resulting in higher outlet temperatures, while increasing the inlet temperature from 290 K to 310 K led to a marked increase in outlet temperatures throughout the day. These findings underscore the importance of optimizing PCM selection, inlet velocity, and temperature in enhancing the performance of solar thermal systems, offering quantitative insights that contribute to the development of more efficient and reliable renewable energy solutions. [ABSTRACT FROM AUTHOR]

The market share of blade batteries is rising rapidly due to their high energy density, efficient space utilization, and low cost. Nevertheless, effective cooling solutions for blade batteries are crucial to ensure the safe operation of electric vehicles, especially in extreme high-temperature environments. This paper numerically investigates the effects of a cooling plate and the blade battery parameters on maximum battery temperature, maximum temperature difference, and cooling water pressure drop. Additionally, the energy efficiency of these solutions under various cooling demands is analyzed. The numerical results show that increasing the channel number and changing the flow direction does not significantly improve the cooling performance of the cooling plate. Moreover, the effect of cooling water temperature on the maximum temperature difference in blade batteries is negligible. Furthermore, increasing the cooling water mass flow rate and the rotational speed of the cooling fan is preferred when Tmax − Ta > 6 K, while reducing the cooling water temperature is more energy-efficient when Tmax − Ta < 6 K. These results are expected to offer theoretical guidance and data support for designing cooling systems for blade batteries in extreme high-temperature environments. [ABSTRACT FROM AUTHOR]

In contemporary vehicle applications, lithium-ion batteries have become a leading option among the diverse array of battery technologies available. This preference is attributed to their advantageous properties, which include low self-discharge rates and no memory effect. Despite these benefits, lithium-ion batteries are not without their challenges. The key issues include a restricted driving range, concerns regarding longevity, safety risks, and prolonged charging durations. Efforts aimed at minimizing the charging duration frequently entail the introduction of elevated currents into the battery, a practice that can significantly elevate its temperature and, in turn, diminish its operational lifespan. Generally, battery packs in electric vehicles are equipped with flat cooling plates located on their side or bottom surfaces, which also serve the dual purpose of providing heating in colder conditions. Nevertheless, this cooling configuration faces difficulties during fast charging and may not efficiently heat or cool the batteries. In this work, a novel thermal management approach is proposed, in which a battery module is cooled not only with a bottom cooling plate but also using another cooling plate in contact with the busbars, located on the top of the battery module. The simulations and experimental tests show that this new configuration demonstrates significant improvements. The thermal time constant is reduced by 47%, enabling faster cooling of the module. Additionally, the maximum temperature reached by the battery during charging with dual cooling is lowered by 6 °C compared to the conventional approach. In this configuration, the top cooling plate acts as a thermal bridge. This is a key advantage that promotes temperature homogenization within the battery module. As a result, it supports an even aging process of batteries, ensuring their longevity and optimal performance. [ABSTRACT FROM AUTHOR]

Energy efficiency is critical for achieving building sustainability because it means that fewer resources are consumed. In this context, the advancement of phase-changing materials has attracted attention with regard to the integration and management of energy efficiency in construction projects. Buildings consume 40% of the global energy output annually, accounting for one-third of the global greenhouse gas emissions. For hot weather-prone construction, PCMs should have a melting temperature of 25–50 °C. For more than 30 years, researchers worldwide have experimented with PCMs at various temperatures, but few studies have been conducted in hot or harsh environments. According to recent studies, the amount of PCMs in construction materials has been limited to 20%, and exceeding this ratio was shown to significantly affect the compressive strength of concrete specimens. In this study, various phase-changing concrete materials were investigated to reduce the thermal energy consumption of buildings. This paper aims to provide an overview of the current state-of-the-art phase change materials for constructing thermal energy storage building materials. It also includes a brief review of the most recent developments in phase change technologies and their encapsulation techniques based on thermophysical properties. Implementing PCM technology in buildings will also maintain good indoor air quality. These materials are widely used in various real-time applications to significantly enhance thermal comfort in buildings. [ABSTRACT FROM AUTHOR]

Epoxy resin, characterized by prominent mechanical and electric‐insulation properties, is the preferred material for packaging power electronic devices. Unfortunately, the efficient recycling and reuse of epoxy materials with thermally cross‐linked molecular structures has become a daunting challenge. Here, we propose an economical and operable recycling strategy to regenerate waste epoxy resin into a high‐performance material. Different particle size of waste epoxy micro‐spheres (100–600 μm) with core‐shell structure is obtained through simple mechanical crushing and boron nitride surface treatment. By using smattering epoxy monomer as an adhesive, an eco‐friendly composite material with a "brick‐wall structure" can be formed. The continuous boron nitride pathway with efficient thermal conductivity endows eco‐friendly composite materials with a preeminent thermal conductivity of 3.71 W m−1 K−1 at a low content of 8.5 vol% h‐BN, superior to pure epoxy resin (0.21 W m−1 K−1). The composite, after secondary recycling and reuse, still maintains a thermal conductivity of 2.12 W m−1 K−1 and has mechanical and insulation properties comparable to the new epoxy resin (energy storage modulus of 2326.3 MPa and breakdown strength of 40.18 kV mm−1). This strategy expands the sustainable application prospects of thermosetting polymers, offering extremely high economic and environmental value. [ABSTRACT FROM AUTHOR]

In the rapidly advancing field of 5G technology, efficient thermal management is essential for enhancing the performance and reliability of high-power-density integrated circuits (ICs). This paper introduces an innovative approach to cooling these critical components, significantly surpassing traditional methods. Our design optimizes heatsink and fan configurations through systematic experimentation, varying fin shapes, heatsink dimensions, and fan speeds. The results demonstrate that fan velocity is the most critical factor in reducing IC temperatures, as increased airflow dramatically lowers thermal output. Expanding the heatsink surface area further improves heat dissipation by enhancing airflow interaction, while a larger copper heatsink boosts thermal conduction, effectively reducing the final IC temperature. These optimizations streamline the cooling process, minimizing the need for more complex and expensive equipment. This research sets a new benchmark in thermal management, fostering the development of more efficient and reliable electronic systems in the era of advanced wireless communications. Our approach brings a new dimension to existing research by focusing on the optimization of heatsink and airflow designs specifically for ICs. While previous studies have explored broader thermal management strategies, our work addresses specific challenges in heat dissipation by refining geometric configurations and fan speed adjustments. These optimizations result in measurable improvements in both efficiency and scalability, particularly within the context of high-power 5G systems. [ABSTRACT FROM AUTHOR]

The performance of solar photovoltaic (PV) panels is significantly affected by their operating temperature, with higher temperatures leading to decreased efficiency and reduced lifespan. This study explores the enhancement of PV panel performance through the implementation of an advanced cooling technology that combines Phase Change Materials (PCM) with forced convection. The PCM layer, strategically placed at the back of the PV panel, absorbs and stores thermal energy during periods of high solar irradiance, while the forced convection system actively dissipates excess heat. A comprehensive simulation of this hybrid cooling system is conducted using ANSYS software. The simulation involves creating a detailed 3D model of the PV panel, assigning appropriate material properties, and setting up transient thermal analysis to capture the dynamic thermal behavior throughout a typical day. The results indicate that the integration of PCM and forced convection significantly reduces peak temperatures of the PV panels, thereby enhancing their efficiency and potentially increasing their operational lifespan. This innovative cooling solution presents a promising avenue for improving the performance and reliability of solar PV systems. The ANSYS simulation results reveal that the combined PCM and forced convection cooling system effectively reduces the peak temperatures of the solar panels. This temperature reduction significantly improves the electrical efficiency of the panels and suggests the potential for extending their operational life. The study confirms the feasibility of this hybrid cooling method as a practical and effective solution to enhance the performance and reliability of solar panel installations, paving the way for more sustainable and efficient solar energy systems. [ABSTRACT FROM AUTHOR]

Thermal management is essential for maintaining optimal performance across various applications, including personal comfort, electronic systems and industrial processes. Thermal-management fibers and textiles have emerged as innovative solutions to manipulate heat transport, storage and conversion efficiently. This review explores recent advancements in material innovations in this field. We summarize the novel fibers and textiles designed for controlling heat transport through different pathways, progress in developing phase-change-material-based fibers and textiles for heat storage regulation, and application of photothermal conversion, Joule heating and thermoelectric effect as energy conversion routes in advanced fibers and textiles. Furthermore, we discuss the challenges and future perspectives of this field. It is believed that ongoing research and development promise to bring about innovative thermal-management solutions catering to demands across multiple sectors. [ABSTRACT FROM AUTHOR]

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Researchers have attempted to improve heat transfer in mini/microchannel heat sinks by dispersing nano-encapsulated phase change (NPC) materials in base coolants. While NPC slurries have demonstrated improved heat transfer performance, their applications are limited by decreasing enhancement at increased flow rates. To address this challenge, the present study numerically investigates the effects of wavy channels on the performance of NPC slurries. Simulation results reveal that a wavy channel induces Dean vortices that intensify the mixing of the working fluid and enlarge the melting fractions of the NPC material, thus offering a significantly higher heat transfer efficiency than a straight channel. Moreover, heat transfer enhancement by NPC slurries varies with the imposed heat flux and flow rate. Interestingly, the maximum heat transfer enhancement obtained with the wavy channel not only exceeds the straight one, but also occurs at a higher heat flux and faster flow rate. This finding demonstrates the advantage of wavy channels in management of intensive heat fluxes with NPC slurries. The study also investigates wavy channels with varying amplitude and wavelength. Increasing the wave aspect ratio from 0.2 to 0.588 strengthens Dean vortices and consequently increases the Nusselt number, optimal heat flux, and overall thermal performance factor. [ABSTRACT FROM AUTHOR]

The fast charge and discharge of a battery will significantly increase the overall temperature and thermal difference of the battery, which will further affect the working performance and safety of the battery. Therefore, a heat–fluid coupling topology optimization pipeline for developing radiation performance of the cooling plate is presented to ensure the thermal homogeneity of the battery in this paper. First, the Brinkman penalty model is utilized to construct the solid and fluid structures. Then, a local volume constraint is introduced to create the lattice structure to reduce the temperature difference of the cooling plate. Furthermore, a functionally graded lattice structure via a variable influence radius is presented to improve the radiation performance of the cooling plate when the thermal load is uneven. Numerical experiments are carried out to evaluate the performance of the presented methods on the optimization of the cooling plate, which indicates that the designed cooling plate by the proposed method improves the radiation performance when compared against a traditional straight channel and a SIMP-based optimal design. [ABSTRACT FROM AUTHOR]

To protect the environment and reduce dependence on fossil fuels, the world is shifting towards electric vehicles (EVs) as a sustainable solution. The development of fast charging technologies for EVs to reduce charging time and increase operating range is essential to replace traditional internal combustion engine (ICE) vehicles. Lithium-ion batteries (LIBs) are efficient energy storage systems in EVs. However, the efficiency of LIBs depends significantly on their working temperature range. However, the huge amount of heat generated during fast charging increases battery temperature uncontrollably and may lead to thermal runaway, which poses serious hazards during the operation of EVs. In addition, fast charging with high current accelerates battery aging and seriously reduces battery capacity. Therefore, an effective and advanced battery thermal management system (BTMS) is essential to ensure the performance, lifetime, and safety of LIBs, particularly under extreme charging conditions. In this perspective, the current review presents the state-of-the-art thermal management strategies for LIBs during fast charging. The serious thermal problems owing to heat generated during fast charging and its impacts on LIBs are discussed. The core part of this review presents advanced cooling strategies such as indirect liquid cooling, immersion cooling, and hybrid cooling for the thermal management of batteries during fast charging based on recently published research studies in the period of 2019–2024 (5 years). Finally, the key findings and potential directions for next-generation BTMSs toward fast charging are proposed. This review offers an in-depth analysis by providing recommendations and potential solutions to develop reliable and efficient BTMSs for LIBs during fast charging. [ABSTRACT FROM AUTHOR]

The integration of carbon nanomaterials with flexible polymers has received intensive attention as a promising research direction in developing materials with novel properties for advanced applications. Herein, we report on the fabrication and characterization of flexible porous polydimethylsiloxane (PDMS) coated with graphene nanoplatelets (GNPs). We explore the mechanisms affecting its various properties under deformation, and propose new applications for it. The results show lightweight and excellent flexibility characteristics for the obtained GNP-PDMS composite. Measurements of its electrical resistance revealed a change in the electrical resistivity from 2.35 × 106 Ω·m to 194 Ω·m under a strain change from 10 to 80% illustrating its ability to shift behavior from an electrical insulator to a relatively low resistivity material and demonstrating the considerable potential for use as a flexible electrical switch. Moreover, the thermal conductivity of GNP-PDMS was found to be significantly enhanced (up to ∼ 110%) by changing the level of compression from 20 to 80%, proving a strain-tunable thermal performance, allowing its utilization as an insulation material of variable conductance for unique thermal management applications. [ABSTRACT FROM AUTHOR]

Phase Change Material-based Battery Thermal Management System (PCM-based BTMS) has become a current research hotspot due to its high efficiency, thermal stability, and compactness. Regrettably, most existing research on PCM-based BTMS neglects the existence of mechanical vibrations, despite the inevitable involvement of such vibrations in the operating conditions of BTMS in electric vehicles. Therefore, in this study, a PCM-based BTMS is applied to a 6-cell lithium-ion battery (LIB) module, and then numerical simulation is employed to comprehensively evaluate the BTMS's performance in the existence of mechanical vibration. The findings indicate that, under mechanical vibration condition, mechanical vibration's influence on the performance of the BTMS is negligible at lower discharge rates, but becomes significant when the discharge rate surpasses a certain threshold, particularly at extremely fast discharge level, resulting in a decrease of 2.28 K in the LIB module’s maximum temperature and a more uniform temperature distribution upon completion of an 8 C discharge in contrast to its stationary equivalent. Furthermore, mechanical vibration only effectively enhances the BTMS’s thermal absorption capability when the PCM thickness surpasses a certain value, and this vibration also improves the capability of the BTMS to achieve uniform temperature distribution in the LIB module, especially for larger PCM thicknesses. Lastly, the BTMS's performance is able to strengthened by raising vibrational amplitude, but the impact is negligible when the amplitude is equal to or greater than 50 mm, and the thermal absorption capability of the BTMS can be augmented by raising the vibrational frequency, but there exists an enhancement limit. This work promotes the use of PCM-based BTMS in real-world applications and contributes to the advancement of LIB towards higher discharge rates.

[Display omitted] The demand for flexible composite films with electromagnetic interference (EMI) shielding capabilities is rapidly increasing. Balancing high EMI performance with flexibility and portability has become a critical research focus in practical applications. In this study, an optimized strategy for aramid nanofibers (ANF) films was developed using spin-coating and sol–gel techniques. The resulting film features a smooth surface and excellent mechanical properties. ANF, initially an insulator, was transformed into a conductor through the in-situ polymerization of ion-doped polypyrrole (PPy). Leveraging a multilayer structural strategy, we prepared a symmetric composite film, ANF@PPy-(TA-MXene)-AgNWs-(TA-MXene)-ANF@PPy (PMA), using vacuum-assisted filtration and lamination hot pressing. This film, composed of ANF@PPy (PA) as the matrix, tannic acid (TA) modified MXene, and silver nanowires (AgNWs) as fillers, exhibited multiple shielding mechanisms as electromagnetic wave (EMW) passed through its various layers. This multilayer configuration provides significant flexibility in EMW shielding. Moreover, TA-modified MXene expands the lamellar spacing, enhancing the scattering efficiency of EMWs within the film, and serves as a medium connecting the upper and lower layers. This results in the efficient integration of the multilayer structure, synergistically improving both EMI shielding performance and mechanical properties. When the ratio of PA/MXene/AgNWs was 1:3:1, the film demonstrated optimal properties, including an EMI shielding effectiveness of 70.2 dB, thermal conductivity of 4.62 W/(m•K), and tensile strength of 50.2 MPa. Due to the exceptional EMI shielding and thermal properties of the PMA composite film, it holds great potential for applications in artificial intelligence, wearable heaters, and military equipment. [ABSTRACT FROM AUTHOR]

Abstract The rapid evolution of power electronics has triggered an intensified focus on thermal management within electronics circuits, stemming from the critical necessity to mitigate thermal-related failure rates. Thermal management in power electronics circuits relies heavily on efficient heat transfer to prevent overheating of components and ensure their reliable operation, optimal performance, and safety. To facilitate the effective heat transfer, a thermal interface material (TIM) is utilized between switching components such as MOSFETs and heat sinks to improve surface contact, which increases heat transfer. In this research work, a novel thermal interface material (TIM) based on Tungsten-Gallium is introduced and evaluated to enhance thermal properties such as thermal conductivity and viscosity of Gallium-based TIM material with the addition of Tungsten microparticles. The study involves the examination of three distinct TIM samples with varying Tungsten content. Their surface morphology, composition, and topography were analyzed through techniques such as Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) within the context of a DC-DC boost converter. The results indicate that the addition of Tungsten significantly enhances TIM’s viscosity and fluidity, even at high temperatures reaching up to 308 °C, which is crucial for power electronics circuits. In addition, thermal constant analyzer, and DC-DC converter circuit such as boost converter circuit were utilized for thermal and electrical characterization, respectively. These characterization results demonstrate that 10%/wt. addition of Tungsten can increase the thermal conductivity of Gallium from 13.1 to 22.82 W/m.K at room temperature, which represents an overall 74.2% increase in thermal conductivity. Furthermore, when the proposed TIM sample 2 was used in a boost converter circuit, the switching frequency of MOSFET IRF3808 was increased up to 20 kHz while the conduction losses were also lowest compared to other TIM samples.

Lithium ion batteries are widely used in chemical energy storage systems. However, due to their inherent heat generation characteristics, thermal runaway has become a major safety hazard for chemical energy storage power plants. Therefore, optimizing the design of a battery thermal management system to effectively avoid thermal runaway is crucial for the safe operation of chemical energy storage systems. A new type of parallel serpentine flow channel liquid cooling plate with both series turn back and parallel branch structures is designed. Through simulation experiments, the effects of the flow channel structure of the liquid cooling plate, the layout of the liquid cooling system, and the inlet flow velocity of the coolant on the maximum temperature, temperature uniformity, and inlet and outlet pressure drop are studied to optimize the liquid cooling system. The results show that, under the same coolant inlet flow rate, the maximum temperature of the new channel is reduced by 0.284 9 K, and the temperature difference within the module is reduced by 0.466 3 K compared with the traditional parallel flow channel. The inlet and outlet pressure drop is reduced by 40.18% compared with the traditional serpentine flow channel. Based on the parallel serpentine flow channel liquid cooling plate, the optimal layout scheme for the liquid cooling system is the injection of coolant at the two split ports and the staggered arrangement of the liquid cooling plate. Different liquid cooling plates have different flow velocity settings. The inlet flow velocity of the two liquid cooling plates is set to 0.1 m/s, and the inlet flow velocity of the central liquid cooling plate is set to 0.2 m/s. Compared with the same flow velocity of 0.2 m/s for the four plates, the temperature difference within the battery module group is reduced by 13.62%, the inter column temperature difference is reduced by 82.59%, and the energy consumption is reduced by 44.87%, achieving an optimization effect of 'cost reduction and efficiency enhancement'. A reasonable flow channel structure, staggered cold plate layout, and differentiated inlet flow rate design can optimize the liquid cooling system of battery modules and increase the safety of battery module operation.

Abstract This study presents a comprehensive investigation into a 3D simulation of magnetorheological (MR) conical bearings, focusing on considering viscous dissipation using the conjugated heat transfer approach. The behavior of MR fluids is expressed through the utilization of the Bingham-Papanastasiou constitutive equation. Notably, this study considers variations in viscosity and yield stress as functions of both magnetic field intensity and temperature. The study utilizes a multidisciplinary approach, encompassing fluid dynamics, magnetism, and heat transfer, to model and analyze the behavior of MR fluids within conical bearing geometries. The governing equations containing Cauchy momentum, energy, and Maxwell equations are solved using the finite element method. This research delves into the impacts of viscous dissipation on the functional and characteristic attributes of conical bearings. The energy equations in solid and fluid domains and extended considerations to the plug region within viscous dissipation are specifically addressed. Extensive validation is performed through a comparative analysis involving experimental, numerical, and analytical studies to ensure the validity of results. The results reveal the substantial impact of temperature on both the characteristics and functionality of magnetorheological conical bearings.

Due to the rapid development of the space industry, ever higher demands are being made for the optimization and improvement of spacecraft thermal management systems. Thermal control technology has become one of the key bottlenecks that restrict the level of spacecraft design. In this paper, the thermal management technologies (TMTs) for spacecraft electronics are reviewed according to the different heat transfer processes, including heat acquisition, heat transport, and heat rejection. The researches on efficient heat acquisition include the utilization of high thermal conductance materials, the development of novel package structure based on micro-/nano-electromechanical system (MEMS/NEMS) technologies, and advanced near-junction microfluidic cooling techniques. For the heat transport process, various heat pipes and mechanical pumped fluid loops (MPFLs) are widely implemented to transport heat from heat generation components to the ultimate heat sinks. The heat pipes are divided into two categories based on their structure layout, i.e., separated heat pipes and unseparated heat pipes. The merits and demerits of these heat pipes and MPFLs (including the single-phase MPFL and the two-phase MPFL) are discussed and summarized respectively. In terms of the heat rejection for spacecraft, thermal radiators are normally the sole option due to the unique space environment. To meet the requirements of large heat dissipation power and fluctuated thermal environment, research efforts on the radiators mainly focus on the development of deployable radiators, variable emissivity radiators, and the combination with other techniques. Due to the fluctuated characteristics of the heat power of internal electronics and the outer thermal environment, the phase change materials (PCMs) exhibit great advantages in this scenario and have attracted a lot of research attention. This review aims to serve as a reference guide for the development of thermal management system in the future spacecraft.

As climate change worsens, it is becoming increasingly important to effectively harness and store energy from non-fossil fuels to reduce greenhouse gas emissions. The increasing adoption of various rechargeable batteries is being driven by advancements in non-fossil energy, the development of energy storage technology, and electrification in technological fields such as electric vehicles, photovoltaic thermal energy storage, and aerospace technology. However, the compact size of batteries leads to a significant increase in their internal energy density and temperature. Elevated heat flux and temperature not only limit battery performance but also reduce lifespan and pose safety risks to battery systems. The occurrence of thermal runaway under extreme conditions is a concern as it can result in battery combustion or even explosion. Thus, the implementation of efficient battery thermal management systems is essential. Besides traditional methods such as air cooling, phase change materials, and liquid cooling, in recent years, various novel thermal management technologies, including heat pipes, nanoparticle-enhanced phase change materials, and nanofluids, have been extensively explored. Among these emerging technologies, nanofluid battery thermal management systems have garnered attention due to their significant impact, minimal additional energy consumption, and cost-effectiveness compared with alternative approaches. These systems utilize nanofluids, which are liquids with uniformly dispersed nanoparticles. Nanoparticles can contain oxides such as alumina and titanium dioxide, metals such as silver and copper, and carbon-based materials such as carbon nanotube and nanodiamond. The application of nanoparticles results in an improvement in the thermal conductivity of fluids. Moreover, nanoparticles can also supply extra nuclei, improve surface wettability, and delay bubble coalescence while boiling. Thus, nanofluids can enhance heat transfer in both single-phase and two-phase flows. Given the enhancement of heat transfer, nanofluids exhibit significant potential in battery thermal management. Herein, a systematic review of the research progress on nanofluid battery thermal management systems is presented. First, the structure, working principle, and demands of battery thermal management are given. Afterward, the concept and classification of nanofluids are introduced. Subsequently, the fundamental properties of nanofluids, such as stability, viscosity, thermal conductivity, and electrical conductivity, are elucidated. The article further discusses the current research progress on nanofluid-based battery thermal management systems applied in lithium batteries, fuel cells, and photovoltaic batteries. Finally, some notable challenges associated with nanofluid battery thermal management systems and some future development directions on numerical and experimental research and industrial applications are outlined.

Purpose – This paper is supposed to provide a critical review of current research progress on thermal management in grinding of superalloys, and future directions and challenges. By understanding the current progress and identifying the developing directions, thermal management can be achieved in the grinding of superalloys to significantly improve the grinding quality and efficiency. Design/methodology/approach – The relevant literature is collected from Web of Science, Scopus, CNKI, Google scholar, etc. A total of 185 literature is analyzed, and the findings in the literature are systematically summarized. In this case, the current development and future trends of thermal management in grinding of superalloys can be concluded. Findings – The recent developments in grinding superalloys, demands, challenges and solutions are analyzed. The theoretical basis of thermal management in grinding, the grinding heat partition analysis, is also summarized. The novel methods and technologies for thermal management are developed and reviewed, i.e. new grinding technologies and parameter optimization, super abrasive grinding wheel technologies, improved lubrication, highly efficient coolant delivery and enhanced heat transfer by passive thermal devices. Finally, the future trends and challenges are identified. Originality/value – Superalloys have excellent physical and mechanical properties, e.g. high thermal stability, and good high-temperature strength. The superalloys have been broadly applied in the aerospace, energy and automobile industries. Grinding is one of the most important precision machining technologies for superalloy parts. Owing to the mechanical and physical properties of superalloys, during grinding processes, forces are large and a massive heat is generated. Consequently, the improvement of grinding quality and efficiency is limited. It is important to conduct thermal management in the grinding of superalloys to decrease grinding forces and heat generation. The grinding heat is also dissipated in time by enhanced heat transfer methods. Therefore, it is necessary and valuable to holistically review the current situation of thermal management in grinding of superalloys and also provide the development trends and challenges.

Metal hydride hydrogen storage is a hydrogen storage method based on the principle of chemical absorption. Featuring high volumetric hydrogen storage density and high safety, its potential applications in the field of hydrogen storage on ships have attracted significant attention. Against this background, there is a series of issues to be studied, such as material properties, reactor performance, thermal management systems, cost, etc. This paper categorizes metal hydride hydrogen storage technology, summarizes its working principle and research progress on its material properties, and introduces its applications on ships. Next, combined with the application environment and demands of hydrogen ships, the paper analyzes the technological and economic feasibility of the application of metal hydride hydrogen storage technology on ships. To meet the requirements of hydrogen ships for hydrogen storage capacity and release rate, research on marine metal hydride hydrogen storage systems is introduced, including hydrogen storage system performance research, hydrogen storage reactor structure, reactor structure optimization and design ideas for thermal management systems coupled with marine fuel cell and hydrogen storage systems. Finally, the research direction of marine metal hydride hydrogen storage systems is predicted and summarized.

The major aim of this work is to analyze the thermophysical properties of hybrid nanoliquid inside a square lid driven enclosure under the effect of applied magnetic field and mixed convection. The Hybrid nanofluid is considered a suspension of Iron-oxide (Fe3O4) and Copper (Cu) nanoparticles into water. The cavity walls have varying properties such as top adiabatic wall is moving continuously while the lower wall is maintained at a high constant temperature, in addition, the vertical walls are kept at a low fixed temperature. The magnetic field is applied to the right vertical wall in a horizontal direction. Additionally, the effects of buoyancy forces caused by temperature gradients and shear forces caused by continuous lid motion are considered. The mathematical modelling of problem with all assumptions yields the nonlinear partial differential system. First this system is transferred into non-dimensional form and then transformed system is solved by using Galerkin finite element method (GFEM) along with Gaussian elimination method. Results for isotherms, streamlines and average Nusselt number are obtained versus Richardson number (0.1 ≤ Ri ≤ 15), Grashof number (10 ≤ Gr ≤ 10000), Hartmann number (0 ≤ Ha ≤ 100), volume fractions of solid nanoparticles (0.005 ≤ ϕ1 ≤ 0.02) and (0.005 ≤ ϕ2 ≤ 0.02). It is observed that the Richardson number and Grashof number have significant impacts on both flow velocity and temperature. In addition, concentration of hybrid nanoparticles improves the heat transfer performance. The obtained results may be crucial for thermal management in the cooling of electronics, heat exchangers, solar thermal collectors, industrial operations, medical equipment, HVAC systems, food processing, and renewable energy systems.

The design of an efficient thermal management system for a lithium-ion battery pack hinges on a deep understanding of the cells’ thermal behavior. This understanding can be gained through theoretical or experimental methods. While the theoretical study of the cells using electrochemical and numerical methods requires expensive computing facilities and time, the Equivalent Circuit Model (ECM) offers a more direct approach. However, upfront experimental cell characterization is needed to determine the ECM parameters. In this study, the behavior of a cell is characterized experimentally, and the results are used to build a second-order equivalent electrical circuit model of the cell. This model is then integrated with the cooling system of the battery pack for effective thermal management. The Equivalent Circuit Model estimates the internal heat generation inside the cell using instantaneous load current, terminal voltage, and temperature data. By extrapolating the heat generation data of a single cell, we can determine the heat generation of the cells in the pack. With the implementation of the ECM in the cooling system, the coolant flow rate can be adjusted to ensure the attainment of a safe operating cell temperature. Our study confirms that 14% of pumping power can be reduced when compared to the conventional constant flow rate cooling system, while still maintaining the temperature of the cells within safe limits.

The automotive industry faces development challenges due to emerging technologies, regulatory demands, societal trends, and evolving customer mobility needs. These factors contribute to a wide range of vehicle variants and increasingly complex powertrains. The layout of a vehicle is usually based on standardized driving cycles such as WLTC, gradeability, acceleration test cases, and many more. In real-world driving cycles, however, this can lead to limitations under certain boundary conditions. To ensure that all customer requirements are met, vehicle testing is conducted under extreme environmental conditions, e.g., in Sweden or Spain. One way to reduce the development time while ensuring high product quality and cost-effectiveness is to use model-based methods for the comprehensive design of powertrains. This study presents a layout methodology using a top-down approach. Initially, powertrain-relevant requirements for an exemplary target customer are translated into a specification sheet with specific test cases. An overall vehicle model with detailed thermal sub-models is developed to evaluate the different requirements. A baseline design for a C-segment plug-in hybrid vehicle was developed as part of the FVV research project HyFlex-ICE using standardized test cases, highlighting the influence of customer profiles on the design outcome through varying weighting factors. The target customer’s design is analyzed in four real driving scenarios, considering variations in parameters such as the ambient temperature, traffic, driver type, trailer pulling, and battery state-of-charge, to assess their influence on the target variables. In the next step, the potential of hardware technologies and predictive driving functions is examined in selected driving scenarios based on the identified constraints of the baseline design. As a result, four application-specific technology packages (Cost neutral, Cold country, Hot country, and Premium) for different customer requirements and sales markets are defined, which, finally, demonstrates the applicability of the holistic methodology.

The rapid evolution of power electronics has triggered an intensified focus on thermal management within electronics circuits, stemming from the critical necessity to mitigate thermal-related failure rates. Thermal management in power electronics circuits relies heavily on efficient heat transfer to prevent overheating of components and ensure their reliable operation, optimal performance, and safety. To facilitate the effective heat transfer, a thermal interface material (TIM) is utilized between switching components such as MOSFETs and heat sinks to improve surface contact, which increases heat transfer. In this research work, a novel thermal interface material (TIM) based on Tungsten-Gallium is introduced and evaluated to enhance thermal properties such as thermal conductivity and viscosity of Gallium-based TIM material with the addition of Tungsten microparticles. The study involves the examination of three distinct TIM samples with varying Tungsten content. Their surface morphology, composition, and topography were analyzed through techniques such as Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) within the context of a DC-DC boost converter. The results indicate that the addition of Tungsten significantly enhances TIM's viscosity and fluidity, even at high temperatures reaching up to 308 °C, which is crucial for power electronics circuits. In addition, thermal constant analyzer, and DC-DC converter circuit such as boost converter circuit were utilized for thermal and electrical characterization, respectively. These characterization results demonstrate that 10%/wt. addition of Tungsten can increase the thermal conductivity of Gallium from 13.1 to 22.82 W/m.K at room temperature, which represents an overall 74.2% increase in thermal conductivity. Furthermore, when the proposed TIM sample 2 was used in a boost converter circuit, the switching frequency of MOSFET IRF3808 was increased up to 20 kHz while the conduction losses were also lowest compared to other TIM samples. [ABSTRACT FROM AUTHOR]

Thermal management is crucial in composite part manufacturing, as it directly impacts final quality. Controlling tooling surface temperature is essential to minimize defects and achieve desired mechanical properties. This article explores the use of lattice structures with heat transfer fluid circulation to enhance heat exchange, ensuring composite part quality and improving manufacturing productivity and energy efficiency. These structures improve temperature uniformity, increase heating and cooling rates, and reduce thermal inertia without causing thermal marks, thus decreasing cycle time and energy consumption. A steady-state numerical study examines the impact of geometry and materials on the tooling thermal-hydraulic performance. Analysis of fluid flow and heat transfer highlights the impact of the lattice structure on fluid and heat transfer flows. The disturbance created by lattice structures is the main driving force behind improved heat transfer in the system studied. In the presented configuration, i.e., water and high fluid flow rate, the performances do not depend strongly on the lattice structure material. Even if the lattice structures increase the pressure drop, the system studied generates a higher performance than a conventional thermal management method. Following this numerical study, experimental work was carried out in the unsteady regime, providing a proof of concept. The results show an improvement in the uniformity of the temperature field at the tooling surface during transient phases compared with a conventional design using straight channels. The use of lattice structures improves temperature uniformity at the tooling surface by over 50% and heating and cooling rates by 77%. Finally, the possibility of locally controlling the temperature field by adjusting the porosity of the lattice structure is highlighted. [ABSTRACT FROM AUTHOR]

Laser-driven white lighting is believed to be a future-oriented high-brightness solid-state light (SSL) source, which is confronted with a severe challenge in developing a laser-driven color converter with efficient thermal management. Herein, a unique architecture of phosphor-in-glass film bonded with a microchannel cooling (PiGF-MC) converter was proposed to enable high luminescence saturation for high-brightness laser-driven white lighting. The PiGF consisted of yellow-emitting Y 3 Al 5 O 12 :Ce3+ (YAG) was sintered on an alumina substrate and then soldered on a liquid-cooled microchannel radiator, which realizes outstanding heat dissipation performance of laser-driven PiGF. The PiGF-MC converter possesses luminance saturation threshold under a high laser power density of 21 W mm−2, 2.3 times that of the traditional PiGF-alumina converter (∼9 W mm−2). High-brightness laser-driven white light is achieved by the PiGF-MC with a high luminous flux of 2953 lm@21 W mm−2, and long-term stable optical performance is simultaneously realized. The working temperatures of laser-driven PiGF-MC are all lower than 200 °C under various laser powers. This finding demonstrates the broad prospect of the proposed PiGF-MC converter architecture for next-generation high-brightness laser-driven white lighting. [ABSTRACT FROM AUTHOR]

Multiform NiO nanowalls with a high specific surface area were constructed in situ on carbon foam (CF) to construct NiO@CF/OD composite phase change materials (CPCMs). The synthesis mechanism, microstructures, thermal management capability, and photothermal conversion of NiO@CF/OD CPCMs were systematically studied. Additionally, the collaborative enhancement effects of CF and multiform NiO nanowalls on the thermal properties of OD PCMs were also investigated. NiO@CF not only maintains the porous 3D network structure of CF, but also effectively prevents the aggregation of NiO nanosheets. The chemical structures of NiO@CF/OD CPCMs were analyzed using XRD and FTIR spectroscopy. When combined with CF and NiO nanosheets, OD has high compatibility with NiO@CF. The thermal conductivity of NiO@CF/OD-L CPCMs was 1.12 W/m·K, which is 366.7% higher than that of OD. The improvement in thermal conductivity of CPCMs was theoretically analyzed according to the Debye model. NiO@CF/OD-L CPCMs have a photothermal conversion efficiency up to 77.6%. This article provided a theoretical basis for the optimal design and performance prediction of thermal storage materials and systems. [ABSTRACT FROM AUTHOR]

Metal–oxide–semiconductor field-effect transistors (MOSFETs) are critical in power electronic modules due to their high-power density and rapid switching capabilities. Therefore, effective thermal management is crucial for ensuring reliability and superior performance. This study used finite element analysis (FEA) to evaluate the electro-thermal behavior of MOSFETs with copper clip bonding, showing a significant improvement over aluminum wire bonding. The aluminum wire model reached a maximum temperature of 102.8 °C, while the copper clip reduced this to 74.6 °C. To further optimize the thermal performance, Latin Hypercube Sampling (LHS) generated diverse design points. The FEA results were used to select the Kriging regression model, chosen for its superior accuracy (MSE = 0.036, R2 = 0.997, adjusted R2 = 0.997). The Kriging model was integrated with a Genetic Algorithm (GA), further reducing the maximum temperature to 71.5 °C, a 4.20% improvement over the original copper clip design and a 43.8% reduction compared to aluminum wire bonding. This integration of Kriging and the GA to the MOSFET copper clip package led to a significant improvement in the heat dissipation and overall thermal performance of the MOSFET package, while also reducing the computational power requirements, providing a reliable and efficient solution for the optimization of MOSFET copper clip packages. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive investigation into a 3D simulation of magnetorheological (MR) conical bearings, focusing on considering viscous dissipation using the conjugated heat transfer approach. The behavior of MR fluids is expressed through the utilization of the Bingham-Papanastasiou constitutive equation. Notably, this study considers variations in viscosity and yield stress as functions of both magnetic field intensity and temperature. The study utilizes a multidisciplinary approach, encompassing fluid dynamics, magnetism, and heat transfer, to model and analyze the behavior of MR fluids within conical bearing geometries. The governing equations containing Cauchy momentum, energy, and Maxwell equations are solved using the finite element method. This research delves into the impacts of viscous dissipation on the functional and characteristic attributes of conical bearings. The energy equations in solid and fluid domains and extended considerations to the plug region within viscous dissipation are specifically addressed. Extensive validation is performed through a comparative analysis involving experimental, numerical, and analytical studies to ensure the validity of results. The results reveal the substantial impact of temperature on both the characteristics and functionality of magnetorheological conical bearings. [ABSTRACT FROM AUTHOR]

Engineering a lightweight and thin microwave absorber through the design of multiple heterogeneous interfaces represents a significant challenge. Here, we synthesized a nitrogen (N)-doped Ti 3 C 2 T x @Fe 3 O 4 (N–Ti 3 C 2 T x @Fe 3 O 4) nanocomposite with a sandwich-like structure through a solvothermal approach using hydrazine hydrate as the N donor. The numerous Ti 3 C 2 T x electron transfer pathways of Ti 3 C 2 T x enable the realization of a hierarchical conduction network within N–Ti 3 C 2 T x @Fe 3 O 4. The introduction of defects through N doping and the integration of Fe 3 O 4 with Ti 3 C 2 T x are pivotal for enhancing the dipole polarization. The heterogeneous interfaces in N–Ti 3 C 2 T x @Fe 3 O 4 , coupled with Fe 3 O 4 components, substantially boost the electromagnetic wave (EMW) absorption performance of the composite. An optimal N integration and the loading of Fe 3 O 4 in Ti 3 C 2 T x result in an improved impedance matching of N–Ti 3 C 2 T x @Fe 3 O 4. The synergistic effect of the improved impedance matching and the strong EMW attenuation capability endow N–Ti 3 C 2 T x @Fe 3 O 4 with enhanced microwave absorption (MA) properties. Specifically, at a thickness of 1.04 mm, the composite exhibits the effective absorption bandwidth (3.92 GHz; 14.08–18.00 GHz), surpassing that of Ti 3 C 2 T x. At a thickness of 0.98 mm, it exhibits a maximum reflection loss of −40.28 dB at 17.25 GHz, which substantially exceeds that of Ti 3 C 2 T x. Furthermore, it shows a maximum Radar Cross Section reduction of 21.32 dB cm2. A cotton fabric was coated with N–Ti 3 C 2 T x @Fe 3 O 4 , and it was found to exhibit enhanced heat conduction and dissipation, at rates 3.83 and 4.64 times greater than those of uncoated cotton, respectively. These results highlight the considerable potential of N–Ti 3 C 2 T x @Fe 3 O 4 nanocomposites for use in far-field applications. It is envisaged that the exceptional MA and thermal management properties of N–Ti 3 C 2 T x @Fe 3 O 4 nanocomposites will provide a novel avenue for crafting lightweight and thin EMW absorbing materials. [ABSTRACT FROM AUTHOR]

Recently, thermal regulators based on adsorption in a heat pipe have been proposed. The advantage of these so-called "switchpipes" over similar approaches is their low on state thermal resistance. In this paper, we propose a methodology to calculate and adjust the activation temperature of such switchpipes. For this purpose, we use a mass balance-based model that considers both the heat transfer properties of the heat pipe itself, which depend on the amount of working fluid, and the adsorption equilibrium of the adsorbent used. This model can be used not only to describe the activation behavior of a given heat pipe but also to optimize the configuration of a heat pipe for specific operating conditions and to select appropriate adsorbents. In this paper, we also propose definitions for basic indicators of the activation properties of the heat pipe, such as the activation temperature and the activation temperature span. Finally, a simplified calculation method is presented that allows the selection of the correct adsorbent among all adsorbents with Type IV and Type V adsorption isotherms. [ABSTRACT FROM AUTHOR]

Water scarcity is a serious threat to the survival and development of mankind. Interfacial solar steam generation (ISSG) can alleviate the global freshwater shortage by converting sustainable solar power into thermal energy for desalination. ISSG possesses many advantages such as high photothermal efficiency, robust durability, and environmental friendliness. However, conventional evaporators suffered from huge heat losses in the evaporation process due to the lack of efficient thermal management. Herein, hydrophilic Tencel yarn is applied to fabricate a three-dimensional double-layer fabric evaporator (DLE) with efficient multi-stage thermal management. DLE enables multiple solar absorptions, promotes cold evaporation, and optimizes thermal management. The airflow was utilized after structure engineering for enhanced energy evaporation efficiency. The evaporation rate can reach 2.86 kg·m−2·h−1 under 1 sun (1 kW·m−2), and 6.26 kg·m−2·h−1 at a wind speed of 3 m·s−1. After a long duration of outdoor operation, the average daily evaporation rate remains stable at over 8.9 kg·m−2, and the removal rate of metal ions in seawater reaches 99%. Overall, DLE with efficient and durable three-dimensional multi-stage thermal management exhibits excellent practicality for solar desalination. [ABSTRACT FROM AUTHOR]

Maintaining high surface area and porosity at high temperatures is important when considering aerogels for use in thermal management systems. The mesoporous structure of aerogels results in extremely low thermal conductivity, making them lightweight, high performance insulating materials. Maintaining these properties requires innovative routes to suppress sintering and pore collapse as use temperatures rise. The current work aims to improve the pore structure stability of yttria‐stabilized zirconia aerogels by the addition of a SiO2 coating. The functionalization of surface hydroxyl groups by the addition of SiO2 is hypothesized to mitigate condensation reactions, which are a driving force for shrinkage and pore structure collapse. Zirconia aerogels with 0, 10, and 30 mol% yttria (YO1.5) additions were coated in a tetraethyl orthosilicate (TEOS) solution and exposed to temperatures up to 1200°C. Crystal structure, pore structure, and aerogel morphology were investigated to understand changes in aerogel thermal stability. The SiO2 coating exhibited a greater influence on pore stability over yttria concentration, with specific surface area of the coated aerogels being twice that of the uncoated aerogels up to 1000°C. However, the presence of the SiO2 coating promoted rapid sintering and densification at 1200°C, establishing an upper use temperature for SiO2 and a need to develop other coating chemistries. [ABSTRACT FROM AUTHOR]

The automotive industry faces development challenges due to emerging technologies, regulatory demands, societal trends, and evolving customer mobility needs. These factors contribute to a wide range of vehicle variants and increasingly complex powertrains. The layout of a vehicle is usually based on standardized driving cycles such as WLTC, gradeability, acceleration test cases, and many more. In real-world driving cycles, however, this can lead to limitations under certain boundary conditions. To ensure that all customer requirements are met, vehicle testing is conducted under extreme environmental conditions, e.g., in Sweden or Spain. One way to reduce the development time while ensuring high product quality and cost-effectiveness is to use model-based methods for the comprehensive design of powertrains. This study presents a layout methodology using a top-down approach. Initially, powertrain-relevant requirements for an exemplary target customer are translated into a specification sheet with specific test cases. An overall vehicle model with detailed thermal sub-models is developed to evaluate the different requirements. A baseline design for a C-segment plug-in hybrid vehicle was developed as part of the FVV research project HyFlex-ICE using standardized test cases, highlighting the influence of customer profiles on the design outcome through varying weighting factors. The target customer's design is analyzed in four real driving scenarios, considering variations in parameters such as the ambient temperature, traffic, driver type, trailer pulling, and battery state-of-charge, to assess their influence on the target variables. In the next step, the potential of hardware technologies and predictive driving functions is examined in selected driving scenarios based on the identified constraints of the baseline design. As a result, four application-specific technology packages (Cost neutral, Cold country, Hot country, and Premium) for different customer requirements and sales markets are defined, which, finally, demonstrates the applicability of the holistic methodology. [ABSTRACT FROM AUTHOR]

The design of an efficient thermal management system for a lithium-ion battery pack hinges on a deep understanding of the cells' thermal behavior. This understanding can be gained through theoretical or experimental methods. While the theoretical study of the cells using electrochemical and numerical methods requires expensive computing facilities and time, the Equivalent Circuit Model (ECM) offers a more direct approach. However, upfront experimental cell characterization is needed to determine the ECM parameters. In this study, the behavior of a cell is characterized experimentally, and the results are used to build a second-order equivalent electrical circuit model of the cell. This model is then integrated with the cooling system of the battery pack for effective thermal management. The Equivalent Circuit Model estimates the internal heat generation inside the cell using instantaneous load current, terminal voltage, and temperature data. By extrapolating the heat generation data of a single cell, we can determine the heat generation of the cells in the pack. With the implementation of the ECM in the cooling system, the coolant flow rate can be adjusted to ensure the attainment of a safe operating cell temperature. Our study confirms that 14% of pumping power can be reduced when compared to the conventional constant flow rate cooling system, while still maintaining the temperature of the cells within safe limits. [ABSTRACT FROM AUTHOR]

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High-performance computing (HPC) in data centers increases energy use and operational costs. Therefore, it is necessary to efficiently manage resources for the sustainability of and reduction in the carbon footprint. This research analyzes and optimizes ENEA HPC data centers, particularly the CRESCO6 cluster. The study starts by gathering and cleaning extensive datasets consisting of job schedules, environmental conditions, cooling systems, and sensors. Descriptive statistics accompanied with visualizations provide deep insight into collated data. Inferential statistics are then used to investigate relationships between various operational variables. Finally, machine learning models predict the average hot-aisle temperature based on cooling parameters, which can be used to determine optimal cooling settings. Furthermore, idle periods for computing nodes are analyzed to estimate wasted energy, as well as for evaluating the effect that idle node shutdown will have on the thermal characteristics of the data center under consideration. It closes with a discussion on how statistical and machine learning techniques can improve operations in a data center by focusing on important variables that determine consumption patterns. [ABSTRACT FROM AUTHOR]

In thermal management applications using two-phase flow boiling, rectangular microchannels hold significant promise due to their ease of manufacturing and effective heat transfer characteristics. In this work, we combined experimental and theoretical analyses to propose a theoretical model based on thin liquid film evaporation for predicting heat transfer performance in rectangular cross-sectional microchannels. The heat transfer model is segmented into five zones based on two-phase flow patterns and transient liquid film thickness. These zones represent different flow boiling heat transfer mechanisms over time in microchannels: the liquid slug zone, elongated bubble zone, long-side wall dryout zone, corner liquid evaporation zone, and full dryout zone. The new model comprehensively explains experimental phenomena observed, including long-side wall dryout and thinning of the liquid film on the short-side wall. To validate our model, numerical solutions were computed to study the spatial and temporal variations in heat transfer coefficients. The results exhibited a consistent trend with experimental data regarding average heat transfer coefficients. We also analyzed factors influencing flow boiling characteristics, such as microchannel aspect ratio, hydraulic diameter, measurement location, fluid mass flux, and wall heat flux. [ABSTRACT FROM AUTHOR]

Against the backdrop of climate policy goals and the EU's aim for a resource-efficient economy, the foundry industry must rethink product range, energy consumption, and production technologies. Light metal casting, which is performed through processes like gravity die casting and high-pressure die casting, requires effective thermal management, which is crucial for optimising mould filling, solidification, cycle times, and part quality. Against this background, this study presents the development and characterisation of a cooling system that completely dispenses with energy-intensive heating/cooling devices. The system is based on a mask shape combined with internal spray cooling. This paper shows the simulation workflow for developing the mould mask and the design of the cooling system and compares the performance with conventional temperature control using channels. In the tests, an 82% higher cooling rate was achieved with Cool-Spray than with conventional temperature control, which was approx. 2.5 mm below the cavity surface. In addition to the more dynamic temperature control, the potential for process control was utilised, and the component quality of the test part was significantly improved compared to conventional temperature control. [ABSTRACT FROM AUTHOR]

Understanding the behavior of pressure increases in lithium-ion (Li-ion) cells is essential for prolonging the lifespan of Li-ion battery cells and minimizing the safety risks associated with cell aging. This work investigates the effects of C-rates and temperature on pressure behavior in commercial lithium cobalt oxide (LCO)/graphite pouch cells. The battery is volumetrically constrained, and the mechanical pressure response is measured using a force gauge as the battery is cycled. The effect of the C-rate (1C, 2C, and 3C) and ambient temperature (10 °C, 25 °C, and 40 °C) on the increase in battery pressure is investigated. By analyzing the change in the minimum, maximum, and pressure difference per cycle, we identify and discuss the effects of different factors (i.e., SEI layer damage, electrolyte decomposition, lithium plating) on the pressure behavior. Operating at high C-rates or low temperatures rapidly increases the residual pressure as the battery is cycled. The results suggest that lithium plating is predominantly responsible for battery expansion and pressure increase during the cycle aging of Li-ion cells rather than electrolyte decomposition. Electrochemical impedance spectroscopy (EIS) measurements can support our conclusions. Postmortem analysis of the aged cells was performed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) to confirm the occurrence of lithium plating and film growth on the anodes of the aged cells. This study demonstrates that pressure measurements can provide insights into the aging mechanisms of Li-ion batteries and can be used as a reliable predictor of battery degradation. [ABSTRACT FROM AUTHOR]

Electrifying aircraft, a crucial advancement in the aviation industry, aims to cut pollutive emissions and boost energy efficiency. Traditional aircraft depend on fossil fuels, which contribute significantly to greenhouse gas emissions and environmental pollution. Despite progress in electric propulsion and energy storage technologies, challenges such as low energy density and integration issues persist. This paper provides a comprehensive thematic and bibliometric analysis to map the research landscape in aircraft electrification, identifying key research themes, influential contributors, and emerging trends. This study applies natural language processing to unstructured bibliographic data and cross-sectional statistical methods to analyze publications, citations, and keyword distributions across various categories related to aircraft electrification. The findings reveal significant growth in research output, particularly in energy management and multidisciplinary design analysis. Collaborative networks highlight key international partnerships, with the United States and China being key research hubs, while citation metrics highlight the impact of leading researchers and institutions in these countries. This study provides valuable insights for researchers, policymakers, and industry stakeholders, guiding future research directions and collaborations. [ABSTRACT FROM AUTHOR]

Energy and environmental issues have increasingly garnered significant attention for sustainable development. Flexible and shape‐stable phase change materials display great potential in regulation of environmental temperature for energy saving and human comfort. Here, inspired by the water absorption behavior of salt‐tolerant animals and plants in salinity environment and the Hofmeister theory, highly stable phase change salogels (PCSGs) are fabricated through in situ polymerization of hydrophilic monomers in molten salt hydrates, which can serve multiple functions including thermal management patches, smart windows, and ice blocking coatings. The gelation principles of the polymer in high ion concentration solution are explored through the density functional theory simulation and verified the feasibility of four types of salt hydrates. The high concentration chaotropic ions strongly interacted with polymer chains and promoted the gelation at low polymer concentrations which derive highly‐stable and ultra‐moisturizing PCSGs with high latent heat (> 200 J g−1). The synergistic adhesion and transparency switching abilities accompanied with phase transition enable their smart thermal management. The study resolves the melting leakage and thermal cycling stability of salt hydrates, and open an avenue to fabricate flexible PCM of low cost, high latent heat, and long‐term durability for energy‐saving, ice‐blocking, and thermal management. [ABSTRACT FROM AUTHOR]