Review
Thermodynamics
Michael J. Gibbons, Marco Marengo, Tim Persoons
Summary: The emergence of foldable and wearable devices like Samsung Galaxy Fold and Huawei Mate X has led to a demand for increased battery capacity and processor performance, as well as the need for flexible thermal management solutions. This research provides a comprehensive review of rigid and flexible ultra-thin heat pipe technologies, exploring various types of heat pipes, their thermal performance, novel manufacturing processes, and potential future research directions in this field.
APPLIED THERMAL ENGINEERING
(2021)
Article
Green & Sustainable Science & Technology
Bairi Levi Rakshith, Lazarus Godson Asirvatham, Appadurai Anitha Angeline, Stephen Manova, J. Jefferson Raja Bose, J. Perinba Selvin Raj, Omid Mahian, Somchai Wongwises
Summary: This article provides an overview of the latest advancement in the design and operation of TGPs and its applications. It also summarizes recent experimental and numerical investigations on different types of TGPs. The heat transfer characteristics and mechanisms involved when using different working fluids, wick structures, and materials for enhancing the heat transfer performance and operating range of TGPs are discussed.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2022)
Article
Thermodynamics
Sascha Zimmermann, Robert Dreiling, Thinh Nguyen-Xuan, Michael Pfitzner
Summary: Heat pipes are passive heat transfer devices that are increasingly important in various cooling solutions. A novel method for calculating heat pipe performance accurately predicts the temperature drop of the vapor core. Simulation results show a strong dependence of vapor thermal resistance on evaporation and condensation mass fluxes, thermophysical fluid properties, and local vapor temperature.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Jiale Huang, Jianhua Xiang, Xuyang Chu, Wenjie Sun, Ruiliang Liu, Weisong Ling, Wei Zhou, Sulian Tao
Summary: The Y-shaped flexible branch heat pipe was designed to improve the thermal performance of the polymer tube. Various structural parameters were studied to investigate their effects on the cooling ability, heat load, thermal resistance, and anti-gravity performance of the flexible heat pipe. The findings show that the thermal resistance and cooling performance are interdependent, and the total cooling performance may degrade if one of the condensers fails.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Kalind Baraya, Justin A. Weibel, Suresh V. Garimella
Summary: Heat pipes and vapor chambers are passive thermal management devices used for efficient heat transport by phase change. They can withstand power pulses exceeding the capillary limit for brief time intervals and recover from dryout-induced thermal hysteresis. A new testing protocol is proposed to experimentally characterize the maximum hysteresis signature for a heat pipe after dryout.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
A. R. Anand
Summary: This paper presents a novel method for completely removing noncondensable gas from loop heat pipes (LHPs) using a simple setup. Through a series of test runs, it is demonstrated that this method can effectively remove a certain amount of noncondensable gas.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2022)
Article
Energy & Fuels
Xuepeng Yuan, Yunxian Huang, Xingyu Zheng, Yong Tang, Chunxia Wu, Shiwei Zhang, Caiman Yan
Summary: In this study, a large-area ultra-thin vapor chamber (LUTVC) with a thickness of only 0.5 mm was developed for power battery cooling. Compared to copper sheet cooling, the LUTVC can reduce the maximum temperature of the battery by 2.1 degrees C and 6.7 degrees C at 1 C charging and 1.3 C charging, respectively.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Thermodynamics
Shyy Woei Chang, Guan Wei Chen, Yen Ping Lin, Yi Chun Liao
Summary: A cylindrical vapor chamber design with interior vapor-liquid circulation facilitated by a pulsating heat pipe network was proposed and tested for thermal performance analysis. The study showed that the tilt angle of the vapor chamber had an impact on the thermal resistance of the evaporators, and the power spectrum of the time-domain pressure signal was correlated with the frequency of vapor bubble agitation. Comparative thermal performance analysis of the cylindrical vapor chamber was conducted by referencing literature results.
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2022)
Article
Green & Sustainable Science & Technology
Youtang Wang, Xuyang Liu, Chengyu Li, Bin Zheng, Chunguang Wang, Xin Tian
Summary: In the application of borehole thermal energy storage, ground heat exchangers can show thermal buckling under high temperature load, but increasing initial confining pressure can reduce thermal deformation and residual deformation of the pipe. Buried pipes with symmetrical arc structure can exhibit asymmetric strains and deformation distribution.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2021)
Article
Thermodynamics
Alok Kumar, Suneet Singh
Summary: Heat pipes are used for high-heat transfer in electronic devices. The operation of Pulsating Heat Pipe is not fully understood due to the complexities involved. A phenomenological model has been developed to explain the thermodynamic processes, and the oscillatory behavior of the liquid slug is modeled. The onset of chaotic regimes in the heat transfer has not been addressed in previous works.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Yalong Sun, Fuye Liang, Heng Tang, Yong Tang, Shiwei Zhang, Kian Jon Chua
Summary: Ultrathin flexible heat pipes (FHP) with Microsoroculum fortunei structural-like wicks were fabricated for cooling flexible electronics. The biomimetic wick, composed of copper mesh and porous micropillars, imitated the veins and spores of Microsoroculum fortunei leaves. FHPs with different thicknesses were made by adjusting the height of the micropillars, achieving high thermal conductivity and good bending heat transfer performance. These FHPs maintained excellent heat transfer performance under natural convection conditions, making them suitable for thermal management of flexible electronics.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Yuan-Chun Li, Shwin-Chung Wong
Summary: This study presents the design and performance test results of novel ultra-thin vapor chambers, showcasing their advantages such as lower cost, superior thermal performance, and strong anti-compression ability. The paper examines the performance and capillary blocking phenomena of vapor chambers under different thicknesses and filling ratios.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Yusuf Rahmatullah, Tsrong-Yi Wen
Summary: This paper proposes a novel numerical scheme for vapor chamber simulations, which takes into account flow compressibility and temperature variations within the vapor core. The scheme uses mass/energy source terms based on the Lee model at liquid-vapor interfaces, and does not require presetting the phase change behavior. The results show good agreement between simulations and experiments, demonstrating the numerical stability and applicability of the proposed scheme.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Sai Kiran Hota, Kuan-Lin Lee, Brett Leitherer, George Elias, Greg Hoeschele, Srujan Rokkam
Summary: Two-phase-based heat spreaders are highly sought after for electronics cooling due to their superior thermal performance. Pulsating Heat Pipes (PHPs) offer thickness, shape, and cost advantages over Embedded Heat Pipe (EHP) spreaders. The thermal performance of PHP with different fluids was experimentally determined and compared to EHP. A mathematical model was developed and validated. Propylene-filled PHP performs similarly or better than EHP at low sink temperatures but dries out faster at moderate temperatures. PHP with R245fa and acetone improves with increasing power but has lower thermal conductivity compared to EHP. PHP is lighter than EHP based on weight comparison.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Engineering, Manufacturing
Ankita Pujahari, Sunando Dasgupta, Anandaroop Bhattacharya
Summary: This article presents numerical studies on thin-film evaporation in a thin vapor chamber with micropillar arrays of varying pitch under uniform and nonuniform heat flux conditions. The dry-out heat flux and evaporator surface temperature are used as performance metrics. A numerical model is formulated to account for fluid flow, phase change heat transfer, and capillary pumping action. The results show that a linearly decreasing pillar spacing arrangement improves the cooling limit and reduces the overall evaporator surface temperature compared to uniform spacing. Insights into the fluid flow and heat transfer phenomena in this process are provided, along with design guidelines for pillar arrangements based on power maps.
IEEE TRANSACTIONS ON COMPONENTS PACKAGING AND MANUFACTURING TECHNOLOGY
(2023)
Article
Physics, Applied
Wenjiang Zhou, Yu Dai, Junjie Zhang, Bai Song, Te-Huan Liu, Ronggui Yang
Summary: In this study, the phonon thermal conductivity and mean-free-path spectrum of high-temperature phase SnSe (beta-SnSe) were investigated using the Boltzmann transport equation and ab initio approaches. The results showed a significant reduction in thermal conductivity when considering four-phonon scatterings. It was also suggested that nanostructure engineering could be used to reduce thermal conductivity without sacrificing the power factor.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Dezhao Huang, Qiangsheng Sun, Zeyu Liu, Shen Xu, Ronggui Yang, Yanan Yue
Summary: The authors developed a tip-enhanced Raman thermometry approach to study thermal transport at nanoscale hotspots and predicted the phonon mean free path through a combination of experiments and simulations.
Article
Chemistry, Multidisciplinary
Lu Chen, Te-Huan Liu, Xiangze Wang, Yandong Wang, Xiwei Cui, Qingwei Yan, Le Lv, Junfeng Ying, Jingyao Gao, Meng Han, Jinhong Yu, Chengyi Song, Jinwei Gao, Rong Sun, Chen Xue, Nan Jiang, Tao Deng, Kazuhito Nishimura, Ronggui Yang, Cheng-Te Lin, Wen Dai
Summary: The rapid development of highly integrated microelectronic devices leads to a demand for advanced thermally conductive adhesives (TCAs) to solve the issue of heat transfer. Metal nanoflakes with a natural 2D structure and isotropic thermal conductivity are promising fillers for high-performance TCAs. However, achieving TCAs with thermal conductivity over 10 W m(-1) K-1 at filler content below 30 vol% remains challenging. This study introduces a top-down strategy to prepare 2D Ag nanoflakes with an intrinsic thermal conductivity of 398.2 W m(-1) K-1, reaching 93% of the theoretical value, and demonstrates their superior heat transfer efficiency in microelectronic cooling performance evaluations.
ADVANCED MATERIALS
(2023)
Article
Physics, Applied
Zeyu Xiang, Yu Pang, Xin Qian, Ronggui Yang
Summary: Characterizing spatially varying thermal conductivities is crucial for understanding the structure-property relation in various thermal functional materials. This study presents a machine-learning-based method for directly extracting depth-dependent thermal conductivity profiles from pump-probe phase signals. The proposed method demonstrates excellent performance in accurately reproducing different types of thermal conductivity profiles and shows potential for depth-dependent thermal property mapping.
APPLIED PHYSICS LETTERS
(2023)
Review
Chemistry, Physical
Changkang Du, Xinpeng Zhao, Xin Qian, Congliang Huang, Ronggui Yang
Summary: Solar evaporation technology, which is free of fossil fuel consumption and carbon dioxide emission, has attracted significant research interest in recent years. Although many systems have achieved high evaporation efficiency, the upper limit of this efficiency is not bounded by 100%. In this article, the thermodynamic limit of solar evaporation efficiency is analyzed, and the challenges and potential improvements for heat-localized solar evaporation and their hybrid systems are discussed.
Article
Chemistry, Physical
Zesheng Yang, Muzhang Huang, Ronggui Yang, Jingbo Sun, Xuefei Zhang, Wei Pan, Chunlei Wan
Summary: The high operation temperature of next generation gas turbines poses a challenge for the durability of metallic turbine blades due to near-infrared (NIR) thermal radiation. Although thermal barrier coatings (TBCs) are used for thermal insulation, they are transparent to NIR radiation. This study introduces an NIR metamaterial consisting of Gd2Zr2O7 ceramic matrix with dispersed Pt nanoparticles, which achieves a broadband NIR extinction and effectively shields radiative heat transfer.
Article
Materials Science, Multidisciplinary
Tianbo Lu, Boyi Wang, Guodong Li, Jiawei Yang, Xiaofan Zhang, Nan Chen, Te-Huan Liu, Ronggui Yang, Pingjuan Niu, Zongxiang Kan, Hangtian Zhu, Huaizhou Zhao
Summary: In order to meet the increasing demand for thermoelectric cooling in high heat flux systems, it is necessary to construct high-performance thermoelectric devices with materials that have both high thermoelectric properties and mechanical strength. However, improving the thermoelectric and mechanical properties simultaneously is challenging due to the anisotropic thermal and electrical transports in the layered structure of Bi2Te3. In this study, a hot extrusion (HE) technique was developed to manipulate the texture ordering in Bi2Te3 material, resulting in significant improvements in thermoelectric and mechanical properties.
MATERIALS TODAY PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Yiteng Tu, Xinyu Tan, Guiguang Qi, Xiongbo Yang, Xiqiao Ouyang, Wensheng Yan, Weiwei Hu, Jialin Geng, Ronggui Yang
Summary: Daytime radiative cooling, a passive cooling technology, has attracted significant interest due to its zero energy consumption and zero greenhouse gas emissions. We propose a spectrally selective coating based on tri-cyclodecane dimethanol diacrylate (DCPDA) monomer, which can be fabricated with simple and scalable methods. The coated glass exhibits high transmissivity in the visible wavelengths and high thermal emissivity in the atmospheric window. Outdoor cooling tests demonstrate the sub-ambient cooling capability of the coating applied to aluminum sheets, making it a promising solution for transparent radiative cooling applications.
MATERIALS TODAY PHYSICS
(2023)
Article
Chemistry, Physical
Yuchi Chen, Qiangqiang Huang, Te-Huan Liu, Xin Qian, Ronggui Yang
Summary: This study used molecular dynamics simulations to predict the thermopower of the redox pairs Fe(CN)6(3-)/Fe(CN)6(4-) and Fe3+/Fe2+, and found excellent agreement with experimental values. It was discovered that the thermopower of Fe3+/Fe2+ can be increased from 1.7+/-0.4 mV/K to 3.8+/-0.5 mV/K by increasing the acetone to water fraction. This increase was attributed to the intercalation of acetone molecules into the first solvation shell of Fe2+ at high acetone fractions.
Article
Thermodynamics
Qiangqiang Huang, Yuchi Chen, Xin Qian, Ronggui Yang
Summary: The utilization of low-grade heat sources has been a long-standing challenge due to the limited temperature difference. This study shows that coupling a thermally regenerative electrochemically cycled flow battery with radiative coolers can enhance the energy density and generate additional operating temperature difference. The model also captures the effects of mass transfer and electrochemical kinetics on power density and efficiency.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Thermodynamics
Jing Wu, Hao Zhang, Tianyu Wang, Xin Qian, Bai Song, Te-Huan Liu, Ronggui Yang
Summary: In this study, the pressure-dependent thermal conductivity of isotope-engineered cubic boron nitride (c-BN) was investigated using ab initio calculations and the Boltzmann transport equation. It was found that the thermal conductivity of isotopically mixed c-BN is less sensitive to pressure variations compared to isotope-enriched c-BN. The results provide a fundamental understanding of pressure-dependent phonon transport in c-BN from a microscopic perspective.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Manufacturing
Orion L. Kafka, Jake Benzing, Newell Moser, Li-Anne Liew, Jordan Weaver, Nikolas Hrabe
Summary: This additive manufacturing benchmarking challenge involved predicting stress-strain behavior and fracture location of a tension specimen made from a wafer of nickel alloy IN625 manufactured by laser powder bed fusion (L-PBF). The challenge provided data on chemical composition, grain and sub-grain structure, and pore structure of the specimen. Prediction responses from six different groups were collected, and while some values were over- or under-predicted, no single model performed best at all predictions. Failure-related properties, including fracture prediction, proved to be particularly challenging. Discussions on improving model maturity and measurement uncertainty were also provided.
INTEGRATING MATERIALS AND MANUFACTURING INNOVATION
(2023)
Article
Chemistry, Multidisciplinary
Hao Zhang, Yongsheng Ji, Yonggang Yao, Long Qie, Zhiheng Cheng, Zhihao Ma, Xin Qian, Ronggui Yang, Chenghang Li, Yaqing Guo, Yifei Yuan, Haoyu Xiao, Haiping Yang, Jing Ma, Jun Lu, Yunhui Huang
Summary: Battery recycling is becoming increasingly important due to the widespread use of Li-ion batteries. Direct recycling methods have advantages of high-purity material recovery and lower environmental impact, but most methods are complex and have low yield. This study presents a transient recycling approach with high efficiency for battery materials, achieving a recovery ratio of over 97% and intact metal foil of nearly 100% through shock-type or rolled-over heating.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Green & Sustainable Science & Technology
Weiping Xu, Sihong Gong, Ningsheng Wang, Wenbo Zhao, Hongle Yin, Ronggui Yang, Xiaobo Yin, Gang Tan
Summary: Radiative cooling technology, using a membrane with spectrum-selective optical properties, has been shown to effectively reduce temperatures in grain storage warehouses. Field testing in Hangzhou, China demonstrated temperature reductions of up to 9.8°C and 4°C in headspace and grain respectively. By creating a building model, it was found that significant electricity savings and temperature reductions can be achieved without the use of air conditioning.
Article
Chemistry, Multidisciplinary
Xinpeng Zhao, Ablimit Aili, Dongliang Zhao, Dikai Xu, Xiaobo Yin, Ronggui Yang
Summary: Dynamic control of sunlight entering a building through switchable glazing panels can effectively reduce building energy consumption. The dual-mode glazing panel demonstrated in this study achieved significant cooling and heating performance, leading to potential energy savings in office buildings.
CELL REPORTS PHYSICAL SCIENCE
(2022)
