Article
Thermodynamics
Bo Zhang, Lu Lu, Jinlin Song, Zixue Luo, Qiang Cheng
Summary: This study theoretically investigates the active control of near-field radiative heat transfer between two multilayered metamaterials consisting of two types of magneto-optical materials, graphene and InSb. The study found that active control of the heat transfer can be achieved by applying an external magnetic field and adjusting the chemical potential of graphene. The results show that the heat flux can be significantly enhanced by changing the magnetic field and the chemical potential of graphene, demonstrating the potential for active control of near-field radiative heat transfer.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Chemistry, Multidisciplinary
Lu Lu, Bo Zhang, Han Ou, Bowen Li, Kun Zhou, Jinlin Song, Zixue Luo, Qiang Cheng
Summary: This study investigates the near-field radiative heat transfer (NFRHT) between graphene/hexagonal boron nitride (hBN) systems and demonstrates the NFRHT enhancement effects. The NFRHT enhancements are three times and six times higher than the blackbody limit for graphene/hBN heterostructures and graphene/hBN/graphene multilayers, respectively. The analysis suggests that these enhancements are consequences of the coupled surface plasmon polaritons (SPPs) of graphene and hyperbolic phonon polaritons (HPPs) of hBN.
Article
Optics
Yun Zhou, Panpan He, Sanshui Xiao, Fengwen Kang, Lujun Hong, Yun Shen, Yamei Luo, Jie Xu
Summary: This research demonstrates a method for achieving tunable index-near-zero (INZ) modes in nonreciprocal magneto-optical systems, and presents a novel theoretical analysis. The tunability of INZ modes can be achieved by changing the parameters of the waveguides, and several perfect optical buffers in the microwave and terahertz regimes are proposed. These findings are of great significance for research in areas such as ultra-strong or -fast nonlinearity, perfect cloaking, high-resolution holographic imaging, and wireless communications.
Article
Physics, Applied
Rongqian Wang, Jincheng Lu, Xiaohu Wu, Jiebin Peng, Jian-Hua Jiang
Summary: Twisted bilayer two-dimensional electronic systems allow for the study of quantum materials and lead to exotic phenomena. The coupling of twisted two-dimensional systems via near-field interactions provides a platform for studying localization and lasing in photonics. Theoretical proposals suggest that twisting can be an unprecedented tool to tune the performance of near-field thermophotovoltaic systems, achieving significant tuning of energy efficiency and power through twisting-induced photonic topological transitions.
PHYSICAL REVIEW APPLIED
(2023)
Article
Nanoscience & Nanotechnology
Jihong Zhang, Bing Yang, Kezhang Shi, Haotuo Liu, Xiaohu Wu
Summary: The coupling of SPPs supported by graphene and HPPs supported by HMs effectively enhances photon tunneling and radiative heat transfer. The study shows that increasing the graphene/a-MoO3 cells in multilayer heterostructures can enhance NFRHT when the vacuum gap is less than 50 nm, but suppresses the enhanced performance with larger gap distance. The coupling of SPPs and HPPs in the periodic structure, analyzed by the energy transmission coefficients, determines the performance. The influence of a-MoO3 film thickness and graphene's chemical potential on NFRHT is also investigated. The findings provide guidance for designing high-performance energy transfer and conversion devices based on coupled polaritons.
Article
Chemistry, Multidisciplinary
Zhou Zhou, Renkang Song, Junbo Xu, Xiang Ni, Zijia Dang, Zhichen Zhao, Jiamin Quan, Siyu Dong, Weida Hu, Di Huang, Ke Chen, Zhanshan Wang, Xinbin Cheng, Markus B. Raschke, Andrea Alu, Tao Jiang
Summary: By studying single-layer and twisted bilayer alpha-MoO3/graphene heterostructures, we demonstrate active modulation of the optical response function through IR nanospectroscopic imaging. Our results reveal that graphene doping leads to an increase in the wavelength of phonon polaritons, while the changes in amplitude and dissipation rate differ from the initial expectations. These variations can be attributed to the intricate interplay of gate-dependent components of the phonon polariton complex momentum.
Article
Physics, Multidisciplinary
Gaomin Tang, Lei Zhang, Yong Zhang, Jun Chen, C. T. Chan
Summary: The near-field radiative energy transfer between two separated parallel plates can be controlled by electric current and an in-plane magnetic field, resulting in tunable thermoelectric current generation in graphene. This control is achieved through the interplay between nonreciprocal photon occupation number in graphene and nonreciprocal surface modes in the magneto-optic plate.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Eva Arianna Aurelia Pogna, Leonardo Viti, Antonio Politano, Massimo Brambilla, Gaetano Scamarcio, Miriam Serena Vitiello
Summary: Through near-field microscopy, researchers have explored the rich physics of layered topological insulators Bi2Se3 and Bi2Te2.2Se0.8, revealing the collective modes dominating the optical response in thin flakes, as well as the propagation of phonon-polariton modes influenced by the topological surface states.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Chia-Hung Wu, Chih-Jen Ku, Min-Wen Yu, Jhen-Hong Yang, Pei-Yuan Wu, Chen-Bin Huang, Tien-Chang Lu, Jer-Shing Huang, Satoshi Ishii, Kuo-Ping Chen
Summary: This study explores plasmonic photodetection using graphene as a 2D material, achieving non-scattering near-field detection of surface plasmon polaritons. The maximum photoresponsivity is 29.2 mA W-1, and the polarization state of the input light produces a 400% contrast. This has potential applications in on-chip optoelectronic circuits.
Article
Materials Science, Multidisciplinary
J. Ryan Nolen, Angela Cleri, Kyle Kelley, Evan L. Runnerstrom, Josh Nordlander, Thomas G. Folland, Jon-Paul Maria, Joshua D. Caldwell
Summary: Doped cadmium oxide films exhibit tunable, low-loss surface plasmon polaritons (SPPs) and epsilon-near-zero (ENZ) modes in the midinfrared range. By manipulating the dielectric environment and spatial overlap of the modes, the SPP-ENZ dispersion can be controlled, leading to applications such as waveguiding, thermal emission, and near-field heat transfer.
ADVANCED PHOTONICS RESEARCH
(2022)
Article
Optics
Bin Sun, Feifeng Xie, Yu Luo, Shuai Kang, Jianqiang Liu
Summary: A hybrid system based on graphene/metal electrodes was successfully used to efficiently excite and control plasmonic modes in graphene ribbons, leading to the design of a low-voltage controlled multi-band absorber. This structure has potential applications in integrated photonics compatible with electronic technology, offering a wide range of potential uses.
OPTICS AND LASER TECHNOLOGY
(2021)
Article
Optics
Mehran Habibzadeh, Hua Lin, Sheila Edalatpour
Summary: Graphene is a promising material for near-field radiative heat transfer due to its large heat flux values and the capability to control the heat flux with a bias voltage. However, the presence of a substrate affects the heat transfer coefficient and modulation ratio. This study investigates the effect of substrates on the heat flux and modulation ratio between two graphene sheets, showing that the presence of a substrate reduces both the heat flux and modulation ratio. Dielectric substrates such as BaF2, KCl, NaF, RbCl, and RbBr have the largest modulation ratio and heat flux among the selected substrates.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2023)
Article
Optics
L. Avalos, A. K. Gonzalez-Alcalde, E. Chaikina, E. E. Garcia-Guerrero, A. A. Maradudin, E. R. Mendez
Summary: The study investigates the optical properties of metallic lamellar gratings with sub-wavelength period as a function of groove depth and width. Anomalies are observed under p-polarized illumination due to the excitation of surface plasmon polaritons (SPPs) and their interaction with plasmonic and photonic modes. The propagation constant of SPPs is affected by the presence of corrugations, with new resonances appearing for grooves deeper than half a wavelength.
OPTICS COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Shui-Hua Yang, Yong Zhang, Ming-Qian Yuan, Cheng-Long Zhou, Hong-Liang Yi
Summary: This research investigates the near-field radiative heat transfer between two nanoparticles in the presence of a bilayered hyperbolic metasurface, showing that the topological transition of the surface state under different twisted angles has a significant effect on the heat transfer. Properly adjusting the twisted angles can greatly amplify the heat transfer between nanoparticles, offering a potential for effective energy management at the nanoscale.
Article
Materials Science, Multidisciplinary
Fuwei Yang, Bai Song
Summary: Active control of heat flow is important in thermal management and energy conversion. The study focuses on thermal radiation between twisted bilayer graphene (TBLG), showing that near-field heat flow can vary significantly with twist angle, chemical potential, and temperature. The findings suggest potential for manipulating radiative heat flow through surface plasmons in TBLG.
Article
Thermodynamics
Jun Wu, Feng Wu, Tiancheng Zhao, Mauro Antezza, Xiaohu Wu
Summary: This study introduces a dual-band nonreciprocal thermal emitter achieved by utilizing the magneto-optical material and the coupling effect of two optical Tamm states (OTSs). The emitter exhibits near-complete dual-channel nonreciprocal thermal radiation at the wavelengths of 15.337 μm and 15.731 μm, assisted by the nonreciprocity of the magneto-optical material and the coupling effect of two OTSs for an external magnetic field of 3T and an incident angle of 56 degrees. The work may open the way for constructing dual-band and multi-band nonreciprocal thermal emitters.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Materials Science, Multidisciplinary
Cheng-Long Zhou, Yong Zhang, Zahra Torbatian, Dino Novko, Mauro Antezza, Hong-Liang Yi
Summary: The near-field thermal radiation mechanisms and hybrid polariton effects in a heterostructure composed of hBN film and black phosphorus single layer are investigated. The results show remarkable enhancement of photon tunneling and the formation of unique hybrid polaritons.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Engineering, Electrical & Electronic
Juqi Zhang, Hong Qi, Baohai Gao, Mingjian He, Yatao Ren, Mingxu Su, Xiaoshu Cai
Summary: As a part of industrial process tomography, acoustic tomography (AT) is a promising method for high-quality velocity field measurement, which is widely utilized in the monitoring of multiphase flow, atmospheric environment, and so on. However, the number of installed transducers is restricted, resulting in sparse valid data and ill-posed limited-data linear AT. In this work, a linear independence degree (LID) metric is proposed to optimize the transducer array, based on the prior information that the linear independence of vectors incorporates maximum measurement information. The LID metric is shown to improve the imaging accuracy of arbitrary practical velocity fields based on AT.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Materials Science, Multidisciplinary
Yang Hu, Haotuo Liu, Bing Yang, Kezhang Shi, Mauro Antezza, Xiaohu Wu, Yasong Sun
Summary: Thermal diodes, which allow heat transfer in a preferential direction while being blocked in a reverse direction, have numerous applications in thermal management, information processing, energy harvesting, etc. In this work, a near-field radiative thermal diode (NFRTD) based on two Weyl semimetal (WSM) nanoparticles (NPs) mediated by a WSM planar substrate is proposed. The NFRTD works without an external magnetic field and with flexible temperatures, and exhibits a significantly higher rectification ratio compared to previous works.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Thermodynamics
Baokun Liu, Minggang Luo, Junming Zhao, Linhua Liu, Mauro Antezza
Summary: Near-field radiative heat transfer (NFRHT) has attracted attention due to its intensity beyond the Planck's black-body limit. The insertion of a third object in the proximity of two particles can significantly influence NFRHT. The many-body interaction (MBI) on NFRHT between arbitrary two particles in a system composed of many particles is still not well understood. This study investigates the MBI for different proximate ensembles and provides insights into NFRHT in dense particulate systems.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Juqi Zhang, Hong Qi, Jianze Wu, Mingjian He, Yatao Ren, Mingxu Su, Xiaoshu Cai
Summary: Accurate and high-quality measurement of temperature and velocity fields is important for combustion and flow diagnosis. Nonlinear acoustic tomography (NAT) can monitor these fields simultaneously by observing their induced sound speed changes. However, the ill-posed nature of the tomographic inverse problem and the lack of a priori information may lead to poor robustness, low precision, and artifacts.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Energy & Fuels
Wen -Wen Zhang, Ming-Jian He, Yan-Ming Guo, Bao-Hai Gao, Ya-Tao Ren, Hong Qi
Summary: This study proposes a new way to generate electricity at night by combining PV/TR cell with TEG devices. The comprehensive analysis and prediction models for the hybrid system under positive and negative illumination are established, and the influence of cell temperature and bandgap on the system efficiency and power density is analyzed. The study also establishes a real-time photon-thermal-electric coupling calculation model and evaluates the power output of the hybrid system using environmental data.
Article
Chemistry, Physical
Ming-Jian He, Xue Guo, Hong Qi, Zhi-Heng Zheng, Mauro Antezza, He-Ping Tan
Summary: In this study, the rectification performance of a three-body radiative diode was greatly improved by introducing graphene into the system. The rectification factor of the proposed diode reached 300% with a 350 nm separation distance between the hot and cold terminals. This improvement was primarily attributed to the surface plasmon polaritons of graphene, which enhanced the heat flux in the forward-biased scenario.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Physics, Fluids & Plasmas
Youssef Jeyar, Mauro Antezza, Brahim Guizal
Summary: We propose a numerical method to solve the electromagnetic scattering problem of a dielectric cylinder partially covered with graphene. By using a classical Fourier-Bessel expansion of the electric field inside and outside the cylinder, and incorporating appropriate boundary conditions in the presence of graphene, we introduce auxiliary boundary conditions to account for the singular nature of the electric field at the edges of the graphene sheet. The method is simple and efficient, and allows for the study of diffraction from such structures. We also identify multiple plasmonic resonances due to the presence of surface modes on the coated cylinder.
Article
Chemistry, Physical
Igor V. Bondarev, Michael D. Pugh, Pablo Rodriguez-Lopez, Lilia M. Woods, Mauro Antezza
Summary: We study the long-range Casimir force for in-plane isotropic and anisotropic free-standing transdimensional material slabs within the framework of Lifshitz theory. Our study reveals that the confinement-induced nonlocality weakens the attraction of ultrathin slabs and alters the distance dependence of the material-dependent correction to the Casimir force. Moreover, using a densely packed array of parallel aligned single-wall carbon nanotubes in a finite thickness dielectric layer, we observe strong orientational anisotropy and crossover behavior for the inter-slab attractive force, in addition to its reduction with decreasing slab thickness.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Thermodynamics
Ming-Jian He, Xue Guo, Hong Qi, Ivan Latella, He-Ping Tan
Summary: This study investigates the radiative heat transfer and spatial temperature distributions in periodic systems composed of alternating slabs of two different materials. The results demonstrate that the temperature distributions exhibit an alternating spatial pattern and split into two distinct components corresponding to each material. The spatial temperature variations are attributed to a dual-channel photon heat exchange through a long-range coupling of electromagnetic modes supported by bodies of the same material. The study also analyzes the thermal relaxation of the temperatures in the system and presents the potential application of tunable nonmonotonic temperature variations in transient mode. The proposed dual-channel mechanism for controlling temperature distributions may open new avenues for prospective applications in nano devices, particularly in thermal photon-driven logic circuitry and thermal management.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Materials Science, Multidisciplinary
Cheng-Long Zhou, Gaoming Tang, Yong Zhang, Mauro Antezza, Hong-Liang Yi
Summary: In recent years, there has been increasing interest in studying broken symmetry within crystals due to its potential in improving the control of light propagation. This research investigates the mechanisms of near-field thermal radiation in a low-symmetry Bravais crystal and demonstrates its remarkable potential for noncontact heat dissipation in nanoscale circuits. The findings also show that twist-induced thermal control is enhanced in the low-symmetry Bravais crystal medium, opening up new directions for thermal-radiation control in low-symmetry materials.
Article
Materials Science, Multidisciplinary
Sergey S. Krishtopenko, Mauro Antezza, Frederic Teppe
Summary: Using the self-consistent Born approximation, this study investigates the effect of uncorrelated disorder induced by randomly distributed impurities and fluctuations in Cd composition on the topological phase transition in HgCdTe crystals. The presence of a heavy-hole band in HgCdTe crystals leads to the topological phase transition at much lower disorder strength compared to conventional three-dimensional topological insulators. The theoretical results are also applicable to other narrow-gap zinc-blende semiconductors such as InAs, InSb, and their ternary alloys InAsSb.
Article
Materials Science, Multidisciplinary
Minggang Luo, Junming Zhao, Linhua Liu, Mauro Antezza
Summary: This study focuses on the light-assisted temperature control in a complex nanoparticle network. By analyzing the light-induced thermal behavior, the boundary and quantitative effects of multiple scattering and thermal accumulation are determined using the Green's function approach. The results show that the more compact the nanoparticle ensemble is, the stronger the multiple scattering effect and the weaker the thermal accumulation effect. Furthermore, the polarization-dependent distribution is only observed in the compact ensemble.
Article
Thermodynamics
Mahsa Taghavi, Swapnil Sharma, Vemuri Balakotaiah
Summary: This study investigates the natural convection effects in the insulation layers of spherical storage tanks and their impact on the tanks' performance. The permeability and Rayleigh number of the insulation material are considered as key factors. The results show that as the Rayleigh number increases, new convective cells emerge and cause the cold boundary to approach the external hot boundary. In the case of large temperature differences, multiple solutions may coexist.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinyang Xu, Fangjun Hong, Chaoyang Zhang
Summary: This study introduces a self-induced jet impingement device for enhancing pool boiling performance in high power electronic cooling. Through visualization and parametric investigations, the effects of this device on pool boiling performance are studied, revealing the promotion of additional liquid supply and vapor exhausting. The flow rate of the liquid jet is found to positively impact boiling performance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Wenchao Ke, Yuan Liu, Fissha Biruke Teshome, Zhi Zeng
Summary: Underwater wet laser welding (UWLW) is a promising and labor-saving repair technique. A thermal multi-phase flow model was developed to study the heat transfer, fluid dynamics, and phase transitions during UWLW. The results show that UWLW creates a water keyhole, making the welding environment similar to in air laser welding.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Xingrong Lian, Lin Tian, Zengyao Li, Xinpeng Zhao
Summary: This study investigates the heat transfer mechanisms in natural fiber-derived porous structures and finds that thermal radiation has a significant impact on the thermal conductivity in low-density regions, while natural convection rarely occurs. Insulation materials derived from micron-sized natural fibers can achieve minimum thermal conductivity at specific densities. Strategies to lower the thermal conductivity include increasing porosity and incorporating nanoscale pores using nanosize fibers.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Yasir A. Malik, Kilian Koebschall, Stephan Bansmer, Cameron Tropea, Jeanette Hussong, Philippe Villedieu
Summary: Ice crystal icing is a significant hazard in aviation, and accurate modeling of sticking efficiency is essential. In this study, icing wind tunnel experiments were conducted to quantify the volumetric liquid water fraction, sticking efficiency, and maximum thickness of ice layers. Two measurement techniques, calorimetry and capacitive measurements, were used to measure the liquid water content and distribution in the ice layers. The experiments showed that increasing wet bulb temperatures and substrate heat flux significantly increased sticking efficiency and maximum ice layer thickness.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinqi Hu, Tongtong Geng, Kun Wang, Yuanhong Fan, Chunhua Min, Hsien Chin Su
Summary: This study experimentally examined the heat dissipation of vibrating fans and demonstrated its inherent mechanism through numerical simulation. The results showed that the flow fields induced by the vibrating blades exhibited pulsating features and formed large-scale and small-scale vortical structures, significantly improving heat dissipation. The study also identified the impacts of different blade structures and developed a trapezoidal-folding blade, which effectively reduced the maximum temperature of the heat source and alleviated high-temperature failure crisis.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Dan-Dan Su, Xiao-Bin Li, Hong-Na Zhang, Feng-Chen Li
Summary: The boiling heat transfer of low-boiling-point working fluid is a common heat dissipation technology in electronic equipment cooling. This study analyzed the interfacial boiling behavior of R134a under different conditions and found that factors such as the initial thickness of the liquid film, solid-liquid interaction force, and initial temperature significantly affect the boiling mode and thermal resistance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinyi Wu, Dongke Sun, Wei Chen, Zhenhua Chai
Summary: A unified lattice Boltzmann-phase field scheme is proposed to simulate dendrite growth of binary alloys in the presence of melt convection. The effects of various factors on the growth are investigated numerically, and the model is validated through comparisons and examinations.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Shaokun Ge, Ya Ni, Fubao Zhou, Wangzhaonan Shen, Jia Li, Fengqi Guo, Bobo Shi
Summary: This study investigated the temperature distribution of main cables in a suspension bridge during fire scenarios and proposed a prediction model for the maximum temperature of cables in different lane fires. The results showed that vehicle fires in the emergency lane posed a greater thermal threat to the cables.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Shuang-Ying Wu, Shi-Yao Zhou, Lan Xiao, Jia Luo
Summary: This paper investigates the two-phase flow and heat transfer characteristics of low-velocity jet impacting on a cylindrical surface. The study reveals that the heat transfer regimes are non-phase transition and nucleate boiling with the increase of heat transfer rate. The effects of jet impact height and outlet velocity on local surface temperatures are pronounced at the non-phase transition stage. The growth rates of heat transfer rate and liquid loss rate increase significantly from the non-phase transition to nucleate boiling stage.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Emad Hasani Malekshah, Wlodzimierz Wlodzimierz, Miros law Majkut
Summary: Cavitation has significant practical importance and can be controlled by air injection. This study investigates the natural to ventilated cavitation process around a hydrofoil through numerical and experimental methods. The results show that the location and rate of air injection have a meaningful impact on the characteristics of cavitation.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Feriel Yahiat, Pascale Bouvier, Antoine Beauvillier, Serge Russeil, Christophe Andre, Daniel Bougeard
Summary: This study explores the enhancement of mixing performance in laminar flow equipment by investigating the generation of chaotic advection using wall deformations in annular geometries. The findings demonstrate that the combined geometry can achieve perfect mixing at various Reynolds numbers.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Hui He, Ning Lyu, Caihua Liang, Feng Wang, Xiaosong Zhang
Summary: This study investigates the condensation, frosting, and defrosting processes on superhydrophobic surfaces with millimeter-scale structures. The results reveal that the structures can influence the growth and removal of frost crystals, with the bottom grooves creating a frost-free zone and conical edges promoting higher frost crystal heights. Two effective methods for defrosting are observed: hand-lifting the groove and airfoil retraction contraction on protruding structures. This research provides valuable insights into frost formation and defrosting on millimeter-structured superhydrophobic surfaces, with potential applications in anti-frost engineering.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Thiwanka Arepolage, Christophe Verdy, Thibaut Sylvestre, Aymeric Leray, Sebastien Euphrasie
Summary: This study developed two thermal concentrators, one with a 2D design of uniform thickness and another with a 3D design, using the coordinate transformation technique and metamaterials. By structuring the thermal conductor, the desired local density-heat capacity product and anisotropic thermal conductivities were achieved. The homogenized thermal conductivities were obtained from finite element simulations and cylindrical symmetry consideration. A 3D concentrator was fabricated using 3D metal printing and characterized using a thermal camera. Compared to devices that solely consider anisotropic conductivities, the time evolution characteristics of the metadevice designed with coordinate transformation were closer to those of an ideal concentrator.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Liangyuan Cheng, Qingyang Wang, Jinliang Xu
Summary: In this study, we investigated the supercritical heat transfer of CO2 in a horizontal tube with a diameter of 10.0 mm, covering a wide range of pressures, mass fluxes, and heat fluxes. The study revealed a non-monotonic increase in wall temperatures along the flow direction and observed both positive and negative wall temperature differences between the bottom and top tube. The findings were explained by the thermal conduction in the solid wall interacting with the stratified-wavy flow in the tube.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
