Thermal Management Efficiency Research Articles

Efficiency improvement in silicon and perovskite solar cells through nanofluid cooling using citrate and PVP stabilized silver nanoparticles

This study investigates the enhancement of solar cell efficiency using nanofluid cooling systems, focusing on citrate-stabilized and PVP-stabilized silver nanoparticles. Traditional silicon-based and perovskite solar cells were examined to assess the impact of these nanofluids on efficiency improvement and thermal management. A Central Composite Design (CCD) was employed to vary nanoparticle concentration (0.2–0.8 wt%), coolant flow rate (0.5–1.5 L/min), and solar irradiance (800–1000 W/m²). Efficiency improvements were measured using Ordinary Least Squares (OLS) regression. The experimental setup integrated nanofluid cooling systems with the solar cells, facilitating efficient heat dissipation. Results showed significant efficiency gains: silicon-based cells improved from 15 to 17% with PVP stabilization, and perovskite cells increased from 18 to 21.1%. PVP-stabilized nanofluids exhibited superior thermal conductivity (0.7 W/m K) and lower thermal resistance (0.008 K/W) compared to citrate-stabilized nanofluids, leading to notable reductions in operating temperatures. For silicon cells, temperatures dropped from 50 °C to 40 °C with PVP, and for perovskite cells, from 55 °C to 40 °C. Response Surface Methodology (RSM) identified optimal conditions for maximum efficiency improvement at 0.8 wt% nanoparticle concentration and 1.5 L/min flow rate. These findings underscore the potential of PVP-stabilized nanofluids in enhancing solar cell performance and longevity. Future research should refine the experimental design, increase sample size, and explore other nanoparticle types and stabilization methods to optimize solar cell efficiency and thermal management. This study contributes to the broader goal of promoting the widespread adoption of solar energy as a sustainable alternative to conventional energy sources.

1010 nm Directly LD-Pumped 6kW Monolithic Fiber Laser Employing Long-Tapered Yb3+-Doped Fiber

Utilizing long-wavelength laser diodes (LDs) for pumping to achieve high-power fiber laser output is an effective method for attaining high quantum efficiency and excellent thermal management. In this work, we report on a Master Oscillator Power Amplifier (MOPA)-structured long-tapered Yb3+-doped fiber laser directly pumped by long-wavelength laser diodes. By shifting the center wavelength of the pump source to 1010 nm, the heat generation within the fiber laser is effectively controlled, thereby increasing the transverse mode instability (TMI) threshold. Additionally, the use of a long-tapered fiber enlarges the mode area and suppresses stimulated Raman scattering (SRS) effects that typically arise from increased fiber length. As a result, an output of 6030 W is achieved with an optical-to-optical (O–O) efficiency of 83.7%, a SRS suppression ratio exceeding 50 dB, and no occurrence of dynamic TMI. This approach provides a valuable reference for optimizing long-wavelength pumping to suppress nonlinear effects and also holds potential for wide-temperature operational applications.

Effect of Fin Configuration on the Early Stage of the Melting Process of a Phase Change Material

Thermal storage systems are essential for optimizing energy resource utilization, particularly in the current context where sustainability and efficiency are critical. Phase Change materials (PCMs) offer a promising solution for improving thermal management efficiency without additional power consumption. Considering that the low thermal conductivity of phase change materials (PCMs) is a limiting factor for heat transfer, this study employs the enthalpy-porosity method to analyze the melting characteristics of a high-Prandtl number PCM. Additionally, this study investigated the effect of varying the number of fins in the heat sink on the heat transfer rate. The material melting process was modeled by considering buoyancy effects and treating the flow as incompressible, Newtonian, transient, and laminar. Lauric acid was selected as the working material with temperature-dependent properties that were incorporated into the simulations for greater accuracy. Three different heat sink configurations were analyzed, varying the number of fins from 5 to 10 and their lengths from 0.02 meters to 0.04 meters. The objective was to optimize the cooling performance using aluminum, which was selected for its excellent balance of lightweight properties and high thermal conductivity. This analysis aimed to assess how these variations in the fin count and dimensions affect the overall heat dissipation efficiency and thermal management of the system. The inclusion of a finned heat sink within a heat exchanger has demonstrated significant efficiency, particularly in regions with substantial boundary layer development, resulting in enhanced heat transfer. These findings highlight the effectiveness of using finned heat sinks in these regions. However, an interesting observation emerged regarding the effect of increasing the number of fins over long periods. Although initially beneficial, a larger number of fins eventually led to a reduced performance over time, notably affecting the thermal storage capacity and molten liquid mass production. Additionally, this study elucidates the influence of natural convection on thermal boundary layer development, highlighting the complexity of the heat transfer processes.

Active and hybrid battery thermal management system using microchannels, and phase change materials for efficient energy storage

Efficient battery thermal management (BTM) is key to the safety and performance of Lithium-ion batteries. This study focuses on cooling a module of 15 prismatic Lithium-titanate cells at an 8C discharge rate using finite volume numerical modeling. Initially, the impact of Reynolds numbers and microchannel count on temperature is examined. Then, Phase change materials (PCM) are introduced to increase thermal management efficiency. Three cases for optimizing the hybrid-BTM system are compared: nanoparticles (1%–5% volume fraction), copper foam (93 % porosity), and micro-encapsulated PCM slurry (5%–15 % volume fraction). The results indicate that an increase in microchannels improves the performance evaluation criterion (PEC) by 93.1 %. Additionally, using copper foam increases the PEC by 18.43 %, 17.44 %, 16.53 %, and 16.31 % at Reynolds numbers 800, 1200, 1600, and 2000, respectively. Furthermore, the BTM system using 5 % nanoparticles demonstrates the best performance, reducing the module temperature by 2.41 % in the presence of copper foam and by 1.78 % in the pure state. Moreover, while the MPCM slurry effectively reduces the module temperature to a desirable level, the high pumping costs significantly decrease the PEC. Additionally, the total entropy of the BTM system follows frictional entropy, although thermal entropy effects dominate the PCM.

Tree-inspired fabric-based of carbon fiber photothermal evaporator for highly efficient water-evaporation desalination

Recently, researchers have increasingly focused on interfacial solar evaporation technology due to its potential in addressing freshwater scarcity through its cleanliness, efficiency, cost-effectiveness, and environmental friendliness. However, developing salt-resistant evaporation devices with high performance using simple processing methods remains challenging. This study presents a novel core-spun composite yarn, utilizing Tencel as the core for its water absorption properties and wrapping it with carbon fiber bundles known for their excellent light absorption capabilities. A photothermal composite yarn fabric evaporation device with a bridge-like structure, utilizing carbon fiber and crafted through three-dimensional braiding technology, was developed. The inclusion of polystyrene foam ensures stable floating and excellent thermal insulation, enhancing thermal management efficiency of the evaporator. Results indicate a stable evaporation rate of 1.71 kg·m−2·h−1 under 1 sun illumination and effectively prevents salt crystallization during prolonged simulated seawater evaporation, specifically with a 10 wt% NaCl solution. This research lays a valuable foundation for designing uncomplicated, efficient, and scalable solar water evaporation devices.

DEVELOPING AN EXTRUDER MACHINE OPERATING SYSTEM THROUGH PLC PROGRAMMING WITH HMI DESIGN TO ENHANCE MACHINE OUTPUT AND OVERALL EQUIPMENT EFFECTIVENESS (OEE)

Designing a state-of-the-art PLC-based extrusion machine with a user-friendly HMI ensures seamless operation, enhancing Overall Equipment Effectiveness (OEE). This project focuses on automating an extrusion system with advanced technologies for optimized functionality and reliability. The architecture includes sophisticated components to boost productivity and product quality. Key aspects involve orderly control and synchronization of the extruder motor, feeder motor, lubrication pump, and vacuum pump for consistent performance with precise temperate profile. A significant innovation is the centralized blower system for machine temperature profile analysis and control, replacing individual controllers to enhance thermal management efficiency and ensure uniform temperature distribution. A high-low temperature alarm system alerts operators to deviations, maintaining process stability. Real-time data on current (Amps) and frequency (Hz) is displayed on the HMI from the inverter for monitoring and diagnostics. The system also features machine downline controlling capabilities for efficient management of downstream processes. Collectively, these innovations create a robust, efficient, and user-friendly extrusion machine that enhances OEE and product quality.

Enhancing thermal management efficiency in robotics engineering: Exploring mechanisms, techniques, and modeling approaches

Thermal management is pivotal in robotics engineering, ensuring optimal performance and reliability of robotic systems. This comprehensive review explores various heat dissipation mechanisms, cooling techniques, and thermal modeling approaches employed in robotics engineering. Key topics include conduction-based, convection-based, and radiation-based heat transfer mechanisms, alongside liquid cooling, air cooling, and phase-change cooling techniques. Analytical thermal models, computational fluid dynamics (CFD) simulations, and finite element analysis (FEA) modeling are discussed for their roles in predicting thermal behaviors and optimizing heat dissipation strategies. By synthesizing these advancements, this review provides valuable insights into enhancing thermal management efficiency and ensuring the longevity of robotic systems.

Unraveling the transformative impact of ternary hybrid nanoparticles on overlapped stenosis with electroosmotic vascular flow kinetics and heat transfer

This study examines how ternary hybrid nanoparticles affect electroosmotic vascular flow kinetics and heat transfer. Through a meticulous exploration of their intricate interplay, this research unveils unprecedented insights into their transformative impact. By comprehensively analyzing the dynamics of vascular flow and thermal behavior under the influence of ternary hybrid nanoparticles, novel advancements are revealed. The assessment is innovative because it incorporates electroosmotic force on blood flow that contains three different nanoparticles (Ti O2, Al2O3 and Si O2). To evaluate the numerical solution, an unraveled approach using the finite element method is employed, ensuring both stability and convergence of the solution. The computed numerical results are presented in graphs and tables, showcasing the relationship between key factors. The comparative analysis uncovers the unparalleled performance and remarkable efficacy of these nanoparticles in enhancing the electroosmotic vascular flow and optimizing heat transfer. The electric field due to the electroosmosis flow interacts with flow pattern and influence the potential flow and vortex formation. This research presents a paradigm shift in the understanding of biomedical engineering and fluid dynamics, offering promising prospects for revolutionizing healthcare technologies and achieving unprecedented levels of thermal management efficiency across diverse applications.

High heat transfer plant-inspired neural network structure controlled by variable magnetic field

Efficient heat dissipation and thermal protection present urgent challenges in high-power integrated circuits (ICs). Although applying a coating of highly thermally conductive materials on the surface of ICs is anticipated to mitigate heat concentration issues, ensuring thermal protection for adjacent devices continues to pose a challenge. Inspired by the microstructure of unidirectional nutrient transport in plant roots, this study utilizes magnetic liquid metal droplets to develop a high thermal conductivity network capable of adaptively manipulating the heat transfer path. This approach aims to tackle the challenges of heat concentration, disordered thermal dissipation, and thermal protection for high-power ICs, thereby enhancing thermal management efficiency. By controlling the distribution of the magnetic field, this study orchestrates the structure of the thermal conduction network to ensure rapid and orderly heat dissipation of ICs while simultaneously validating the network's thermal protection performance. The temperature in the IC thermal concentration zone reaches thermal equilibrium at 399.1 K when the ambient temperature is at 295 K. As the ambient temperature rises to 333 K, the temperature in the IC heat concentration zone stabilizes at approximately 400 K. Simultaneously, the temperature at a specific point in the thermal path of the network registers at 341 K, with the temperatures of the devices flanking this point at 314 K. The magnetron thermal conduction network, inspired by the root structure of bionic plants, not only boosts the thermal management efficiency of ICs but also shows promising application prospects in aerospace, electronics, and other related industries.

Research Status of New Energy Vehicle Thermal Management

Thermal management of new energy vehicles, as a way to break through the driving range of new energy vehicles and one of the guarantees of safety performance, has been paid more and more attention to. In order to improve the thermal management efficiency of new energy vehicles, the thermal management mode of the whole vehicle should be optimized, so that different parts can work at a suitable temperature, so as to ensure the functional safety and service life of the vehicle. Based on this, this paper analyzes the passenger cabin thermal management system through Positive Temperature Coefficient (PTC) heating air conditioning, heat pump air conditioning and other technologies. This paper introduces the new energy vehicle battery thermal management system from the aspects of direct cooling mode and heating mode, introduces the battery thermal management system through the analysis of flow charts, and introduces the cooling mode of electric control and motor, and pays attention to some cutting-edge research progress, and summarizes the automobile thermal management technology theory.

A pourable, thermally conductive and electronic insulated phase change material for thermal management of lithium-ion battery

Phase change materials have been widely studied for the applications in the thermal management of lithium-ion batteries. However, the complicated and high-cost pre-pressing and molding assembly processes are usually required, which makes it difficult to be industrialized. Hence, it is necessary to develop an easy-to-pour, highly thermally conductive, and electrically insulated phase change material to meet the requirements of lithium-ion battery. In this study, a pourable phase change material with high thermal conductivity and electrical insulation (PCPM) was prepared based on the electrostatic self-assembly of expanded graphite (EG) and boron nitride (BN). It was found that the volume resistivity of the PCPM could be effectively improved by coating functionalized EG (f-EG) with functionalized BN (f-BN), and when f-EG: f-BN was 1:3, the volume resistivity was increased by 6.18 times compared to that of the PCPM prepared without coating f-BN. Meanwhile, PCPM possessed a lower viscosity of 398.11 cP compared to the PCPM without f-BN, and lower viscosity results in the desired fluidity of the product as a potting material. Compared to pure polymer matrix (PUR), the thermal conductivity of the PCPM with 35 % m-EG@PA (f-EG: f-BN = 1:2) was increased by 200.4 % to 0.6011 W/(m· K). The results of the heating experiment of the simulated battery indicated that the thermal management efficiency of PCPM was significantly higher than that of PUR. At the end of the heating period, the surface temperature of the battery module with PCPM was 5.12 ℃ lower than that of the module with PUR at the end of heating, and 2.41℃ lower than that of the module with commercial high thermal conductive potting compound.

A numerical study of a novel centrally bifurcated mini-channel liquid cooling plate for enhanced heat transfer characteristics

Temperature rise and poor temperature consistency of lithium-ion batteries due to heat accumulation affect the safe application of batteries. Mini-channel structured liquid cooling plates (LCP) with excellent battery thermal management effects is investigated. In order to obtain a better temperature management effect and temperature consistency at lower pressure drops, a double-layer mini-channel structure LCP bifurcated from the center to the periphery is innovatively designed. Using the simulation software, the impact of the novel LCP's structural elements on battery thermal management efficiency is studied. According to research, the LCP with a double-inlet and double-outlet arrangement provides the best temperature control while requiring the lowest pressure drop. With a 25.7 Pa pressure drop, the LCP can decrease the maximum temperature and maximum temperature difference of the battery to 38.83 °C and 6.57 °C during discharging at 2C. Subsequently, the effects of main channel width, branch channel structural elements and inlet mass flow rate on the performance of the LCP are investigated. Compared to the structural elements, the inlet mass flow rate has more influence on the effectiveness of battery thermal management. However, when the inlet mass flow rate is increased to more than 0.8 g ·s−1, the influence gets less significant. Compared to the other four structural LCPs, the batteries maximum temperature and maximum temperature differences while discharging at 2C are the lowest at 0.8 g ·s−1 inlet mass flow rate with just 152 Pa pressure drop, 33.64 °C and 6.89 °C, respectively. All of these findings could be help to optimize the structure design of mini-channel liquid cooling plates used to battery thermal management.

High thermal conductivity composite phase change material with nano-Ag particles modified diatomite and expanded graphite for improving battery thermal management efficiency

Composite phase change materials (CPCMs) with significant amounts of latent heat can absorb and release at a constant transition temperature have attracted much attention in energy storage and electrical vehicles fields. Nevertheless, it is still a great challenge to utilize in battery thermal management system owing to low thermal conductivity and liquid leakage. Although many efforts have endeavored to improve transferring heat capacity, the thermal conductivity of CPCM is still need to explored. Herein, a novel high thermal conductivity and anti-leakage CPCM including polyethylene glycol, nano-Ag particles modified diatomite and expanded graphite (PDAE) has been designed and prepared. And the nano-Ag particles have evenly attached to the surface of diatomite through in-situ chemical reduction reaction and self-assembly technology. The experimental results indicate that PDAE exhibits excellent thermal conductivity with 1.91 W∙m−1∙K−1 owing to three-dimensional heat transferring network constructed by nano-Ag particles and expanded graphite. Moreover, it is no shape variation and leakage of PDAE under continuously heated at 60 °C for 2 h. In addition, the temperature performance of battery modules with the different CPCMs have been compared in detail, the results demonstrates that battery module with PDAE can be maintained below 53 °C and the temperature difference is effectively controlled within 5 °C even at 3C discharging rate after 10 cycles. With these prominent performances, this designed CPCM with high thermal conductivity will offer a promising insight into the passive thermal management system in practical application.

A Review of Thermal Energy Management of Diesel Exhaust after-Treatment Systems Technology and Efficiency Enhancement Approaches

The DOC (diesel oxidation catalyst), DPF (diesel particulate filter), SCR (selective catalytic reduction), and ASC (ammonia slip catalyst) are widely used in diesel exhaust after-treatment systems. The thermal management of after-treatment systems using DOC, DPF, SCR, and ASC were investigated to improve the efficiency of these devices. This paper aims to identify the challenges of this topic and seek novel methods to control the temperature. Insulation methods and catalysts decrease the energy required for thermal management, which improves the efficiency of thermal management. Thermal insulation decreases the heat loss of the exhaust gas, which can reduce the after-treatment light-off time. The DOC light-off time was reduced by 75% under adiabatic conditions. A 400 W microwave can heat the DPF to the soot oxidation temperature of 873 K at a regeneration time of 150 s. An SCR burner can decrease NOx emissions by 93.5%. Electrically heated catalysts can decrease CO, HC, and NOx emissions by 80%, 80%, and 66%, respectively. Phase-change materials can control the SCR temperature with a two-thirds reduction in NOx emissions. Pt-Pd application in the catalyst can decrease the CO light-off temperature to 113 °C. Approaches of catalysts can enhance the efficiency of the after-treatment systems and reduce the energy consumption of thermal management.

Performance simulation of L-shaped heat pipe and air coupled cooling process for ternary lithium battery module

Currently, the conventional heat pipe form and working fluid are not well suited for power batteries. Existing simulation studies on battery thermal management with coupled heat pipes often overlook the two-phase flow and heat transfer of working fluid within the heat pipe. Additionally, the temperature difference between electrode region and cell is neglected in thermal behaviour simulation of the battery. Aiming at these problems, this paper proposes the design of an L-shaped heat pipe, which aims to efficiently adapt to heat dissipation of square batteries and the spatial arrangement within the battery module. And the phase change, flow and heat transfer processes of working fluid inside heat pipe are simulated and reproduced using the VOF (volume of fluid) method. Additionally, a CFD (computational fluid dynamics) model of an 8S1P ternary lithium-ion battery module is established based on the NTGK (Newman, Tiedemann, Gu, and Kim) method. Focusing upon thermal behaviour properties of the 8S1P battery module at different discharge rates, we investigate and optimize the thermal management efficiency of L-shaped heat pipes coupled with air cooling. The analysis reveals that the battery module model provides a more accurate representation of the temperature field on the body of batteries and the temperature variation among them. The evaporation-condensation process of the working fluid inside the heat pipe can continue in dynamic equilibrium, and the heat transfer effect through phase transition is well. With battery discharge rates varying from 1C to 3.5C, the addition of forced air cooling and introduction of cold air from air conditioning allows efficient control of temperature and temperature difference of the module, resulting in an ideal cooling effect. This study further improves the accuracy of the design and simulation of BTM (battery thermal management) that coupled with heat pipes, which can provide certain reference for related research.

Thermal performance of phase change materials with anisotropic carbon fiber inserts

In thermal energy storage systems, phase change materials (PCMs) are widely used for thermal energy management. Most PCMs have low thermal conductivities, which limits the heat transfer rate within PCM and thus makes the phase-changing process very slow. However, thermal conductivities of PCMs can be altered by inserting targeted additives. We hypothesize that the size and shape of these additive inserts play a key role in thermal management efficiency. To this end, the impacts of carbon fiber (CF) inserts on the phase change behavior and consequent heat transfer efficiencies of inorganic and organic PCMs were investigated using experiments and simulations. Long, anisotropic CFs with high thermal conductivities formed continuous fast heat flux tunnels inside PCMs to enhance the heat transfer. Such CFs could extend the phase change fronts from the limited container-shaped interface to the larger surface of numerous CF inserts inside the PCM. These special CF inserts work with a new heat transfer mechanism, different from conventional small additives or long isotropic CF inserts. The thermal energy release rate increased by 2.5 times with 1 wt.% anisotropic CF inserts in inorganic PCM. However, CF inserts in liquid organic PCM hindered the natural convection and compromised the improved heat conduction. The lab-scale multiphysics simulations support these experimental observations and indicate that CF inserts have potential to enhance heat transfer in inorganic PCMs, but they are less effective in organic PCMs.

Flame-retardant composite phase change material with silicone resin and melamine phosphate for battery thermal safety

<p>With the prosperity of electric vehicles (EVs), the thermal management of lithium-ion battery (LIB) is crucial for ensuring the safety of drivers on EVs. Composite phase change material (CPCM) with high latent heat has a great promising prospect in battery thermal management systems (BTMS). However, the thermal management efficiency of CPCM is limited due to the leakage, low thermal conductivity and flammability. Herein, the novel multifunctional CPCM with paraffin (PA), epoxy resin (ER), expanded graphite (EG), methyl MQ silicone resin (MQ) and melamine phosphate (MP) (PEE/MQ/MP3) has been prepared, which can achieve well anti-leakage, high flame-retardant and thermal conductivity, enhancing the thermal safety for battery module. The results reveal that PEE/MQ/MP3 with MQ and MP at a ratio of 1:2 can exhibit optimum flame retardant performance. The total heat release peak, smoke production rate, carbon monoxide production and carbon dioxide production are 169 MJ/m<sup>2</sup>, 0.05 m<sup>2</sup>/s, 0.005 g/s and 0.38 g/s, respectively. The battery module with PEE/MQ/MP3 displays excellent thermal management performance, delaying thermal propagation. Even after ten cycles at a 3 C rate, the maximum temperature is controlled below 50 ��C and the maximum temperature difference is maintained with 5 ��C. Besides, the thermal propagation processes of battery modules reveal that PEE/MQ/MP3 can absorb and transfer heat in the first stage timely and quickly, efficiently suppressing the thermal hazard occurrence. Therefore, this study has proposed a multifunctional flame-retardant CPCM as an effective solution to enhance the thermal safety of battery modules, thus ensuring the safety of EV drivers.</p>

Enhancement of heat transfer efficiency in Li-ion battery packs through response surface optimization of heat pipes

Battery thermal management system (BTMS) ensure optimal performance and safety of Electric vehicle (EV) battery packs. Conventional cooling strategies using heat pipes with air and liquid cooling face challenges in effectively dissipating heat, leading to thermal management issues. This study addresses these limitations by proposing an optimized heat pipe design (helical configured) for enhanced thermal management efficiency. Computational Fluid Dynamics (CFD) simulations evaluate the proposed design for its heat transfer characteristics. The results demonstrated that Air-based cooling systems without heat pipes, in both parallel and staggered arrangements, showed temperature ranges of 30.64∘C to 42.66∘C and 31.14∘C to 41.76∘C, respectively and Liquid cooling systems using water-glycol fluid demonstrated temperature ranges of 30.33∘C to 35.96∘C within the battery pack. This is because the helical configuration provides a larger surface area for heat transfer, allowing for improved heat dissipation. Furthermore, Weight optimization techniques are employed to reduce the overall weight of the battery pack while maintaining structural integrity. The proposed design and optimization strategies contribute to advancing BTMS technology, enhancing battery performance, extending battery life, and ensuring safety. Future research directions include scalability studies for larger battery packs and evaluating the optimized design under various operating conditions. Exploring advanced materials and fabrication techniques can enhance heat transfer capabilities and system efficiency.

Design of PVA/multilayer hybrid particle composite aerogel skeleton supported form-stable phase change materials with high thermal conductivity and solar-to-thermal conversion efficiency

Phase change materials (PCMs) are considered to be promising energy storage materials, but the advanced utilization of PCMs is limited by liquid phase leakage, low thermal conductivity and poor solar-to-thermal conversion ability. Herein, inspired by the structure of nacre, we used boron nitride nanosheets (BNNs) coated with polydopamine (PDA)-modified tetrapod zinc oxide (T-ZnO) to prepare multilayered BNNs/PDA@T-ZnO hybridized particles (BPT), and then employed them to reinforce the PVA aerogel to obtain a BPT/PVA skeleton. Due to the robust support of T-ZnO substrate, BPT/PVA skeleton has ordered porous structure and excellent mechanical properties, with compressive strength up to 15.7 MPa. The prepared composite PCMs of polyethylene glycol (PEG) supported by BPT/PVA skeleton (PVA/BPTs/PEG) have good heat storage capacity, thermal conductivity and solar-to-thermal conversion efficiency. The rigid BPT/PVA skeleton endows PVA/BPTs/PEG with good shape stability and durability, whereas the melting enthalpy and crystallinity of PVA/BPT/PEG reach 139.0 J·g−1 and 99.6 %, respectively. The intermediate dopamine layer of BPT acted as an adhesive for BNNs and T-ZnO and excellent solar-to-thermal conversion medium, which cause the PVA/BPTs/PEG composites to have excellent solar-to-thermal conversion efficiency (95.2 %). Meanwhile, the thermal conductivity of PVA/BPTs/PEG reach 1.34 W·m−1·K−1, benefiting from the continuous 3D heat transfer path provided by the stacked BPT particles. Considering the outstanding overall performance, the prepared composite PCMs have the potential to be suitable for the application of high efficiency thermal management and solar energy utilization.

Experimental study about the impact of open cell aluminium foam (OCAF) insertion in salt-based phase change material (PCM) for electronics thermal management

Thermal management of electronic components is a critical task in a harsh thermal environment. Spacecraft and satellites' electronics are susceptible to highly intermittent heating and cooling thermal conditions, which imposes challenges for robust thermal management system design. Phase change materials (PCM) are a promising solution for overcoming these challenges and enhancing thermal control performance. The lower PCM thermal conductivity and PCM supercooling limit PCM utilisation in electronic thermal control systems. The present study aims to provide solutions for enhancing the heat transfer within the PCM, boosting the PCM thermal conductivity, and diminishing the PCM supercooling. The open-cell aluminium foam (OCAF) was adopted for boosting the heat transfer within the PCM. A thermal management module (TMM) integrated with a salt-based PCM/OCAF composite was developed for electronics thermal management. The TMM was tested under intermittent thermal conditions of heating and cooling. An electric heater and Peltier cooler were affixed to the TMM for the heating and cooling process, respectively. Three levels of heat fluxes were adopted: 700, 1000, and 1400 W/m2. The heating process lasted one hour; then, the TMM was cooled by the Peltier element to the initial temperature. The research novelty covers the gap in understanding how OCAF affects salt-based PCM supercooling when subjected to varying heating loads during intermittent cycles. The outcomes reported a remarkable improvement in thermal management efficiency. The PCM-based TMM reduced the highest temperature by about 20.4 %, 21.6 %, and 23 % at the three heating levels. The OCAF diminished the PCM supercooling curiously. The reduction in PCM supercooling was 43.5 % compared to the 100 % PCM case obtained at the heat flux of 1400 W/m2.