Article
Mathematics
Fatih Selimefendigil, Mohamed Omri, Walid Aich, Hatem Besbes, Nidhal Ben Khedher, Badr M. Alshammari, Lioua Kolsi
Summary: The effects of using wavy wall and different nanoparticle shapes in a thermoelectric generator (TEG) mounted vented cavity were analyzed numerically. The amplitude of the wave has a more significant impact on flow and output power features compared to the wave number. The use of cylindrical-shaped nanoparticles leads to higher powers compared to spherical ones, and the inclusion of both wavy wall and cylindrical-shaped nanoparticles increased TEG power by up to 194%.
Article
Thermodynamics
H. Afsar, G. Peiwei, A. Alshamrani, M. M. Alam, A. S. Hendy, M. A. Zaky
Summary: This article explores the electroosmotic peristaltic flow in asymmetric channels using hybrid non-Newtonian nanofluids and emphasizes its significant potential in various domains such as microfluidics, electronics cooling, energy systems, and biomedical applications.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
P. Sudarsana Reddy, P. Sreedevi
Summary: The heat transfer and flow characteristics of Tiwari-Das model nanofluid inside a differentially heated square enclosure with single walled carbon nanotubes and water, considering thermal radiation, were investigated in this study. Numerical simulations were conducted to analyze the effects of various parameters on the heat transfer performance, showing that the addition of single walled carbon nanotubes can enhance the heat transfer rate of the nanofluid by up to 6%. Additionally, it was observed that the radiation parameter can increase the Nusselt number values inside the cavity. The numerical code used in this study was validated and showed good agreement with available data.
ALEXANDRIA ENGINEERING JOURNAL
(2021)
Article
Thermodynamics
Ali Akbar Abbasian Arani, Ali Memarzadeh
Summary: The research demonstrates that using multimorphology nanofluids can improve the Performance Evaluation Criteria (PEC), with the combination of 20%:80% cylindrical brick portion achieving the best PEC among different proportions. Despite ranking second in terms of Nusselt number and friction factor, it has a significant impact on energy efficiency values.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Roghayeh Bardool, Ali Bakhtyari, Feridun Esmaeilzadeh, Xiaopo Wang
Summary: This study applies the free-volume model and Esmaeilzadeh-Roshanfekr equation of state to calculate the viscosity of nanofluids and proposes a simple modification to improve the model's performance. The results show that the modified model performs better in terms of accuracy compared to the original model.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Thermodynamics
S. E. Ghasemi, Sina Gouran, Ali Zolfagharian
Summary: The main objective of this study is to investigate the thermo-hydraulic behavior of nanofluids in a sinusoidal wavy channel, considering the influences of thermophoresis and Brownian motion. The momentum, continuity, energy, and nanoparticle fraction equations were solved using the differential quadrature method and optimal homotopy asymptotic scheme. Results show that an increase in thermophoresis leads to higher temperature distribution values, while decreasing the thermophoresis parameter enhances the nanoparticle volume fraction.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Wei Wang, Gang Liu, Ben-Wen Li, Zheng-Hua Rao, Huan Wang, Sheng-Ming Liao
Summary: Both experimental and numerical studies show that nanoparticle suspensions enhance heat transfer for forced convection. However, there is diverse or contradictory conclusions regarding buoyancy-induced heat transfer in nanofluids. The study found that the hydrothermal behaviors of nanofluids strongly depend on the interaction between volume fraction and nanoparticle diameter, showing potential for improving heat transfer.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Thermodynamics
Yacine Khetib, Khaled Sedraoui, Ammar A. Melaibari, Ali Alzaied, Radi Alsulami, Mohsen Sharifpur
Summary: This study simulated the turbulent flow of a nanofluid in a channel and investigated the effects of factors such as fin shape and nanoparticle shape on the heatsink temperature and pressure drop. The results showed that increasing velocity leads to lower heatsink temperature, and using brick-shaped nanoparticles and circular fins provides the best cooling performance. Additionally, circular fins and brick-shaped nanoparticles require less pressure drop compared to other cases.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Materials Science, Multidisciplinary
S. R. Mishra, S. Panda, S. Vignesh, P. K. Pattnaik, Vediyappan Govindan, Jagadish V. Tawade, M. Ijaz Khan, Dilsora Abduvalieva, Imen Rashid Bouazzi
Summary: This study investigates the radiative heat characteristics of nanofluid in peristaltic flow through wavy walls of a tapered channel. The effects of slip velocity, Brownian motion, and thermophoresis on flow properties are considered. The governing flow phenomena are solved using the Variation Parameter Method, and the characteristics of the system parameters are presented through graphs. The results show that magnetic strength and flow through the permeable medium enhance the pumping procedure, and considering convective conditions significantly enhances fluid temperature and concentration profiles.
RESULTS IN PHYSICS
(2023)
Article
Chemistry, Physical
Honghe Nong, Abdulnasser Mahmood Fatah, S. A. Shehzad, T. Ambreen, Mahmoud M. Selim, Ahmad B. Albadarin
Summary: The research demonstrates steady-state magnetized nanofluid flow under radiative wavy cavity, modeling the porosity term using non-Darcy's theory. The working nanofluid is based on water-Al2O3 nano-powder with 4% concentration, and numerical modeling is estimated via CVFE technique. Results show that increasing media porosity leads to fluid advection decay and conduction dominates over convection in the process.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Chemistry, Physical
Shubhankar Sarkar, Nanda Kumar Ghosh
Summary: This study investigates the effect of temperature and Ag nanoparticles volume fraction on thermophysical properties such as thermal conductivity (TC), viscosity, and specific heat in Ethylene Glycol (EG) base fluid using molecular dynamics simulation. The results show that the diffusive qualities of nanoparticles relative to the fluid play a role in changing the characteristics of the fluid. The TC of the base fluid increases with temperature, and the enhancement of relative TC to the base fluid is due to the reduction of condensation around the nanoparticle. Viscosity increases with volume fraction but decreases with temperature. Non-linear increment of TC and viscosity with volume fraction is observed, consistent with different models. The study also investigates the mechanism of thermal conductivity enhancement through mean square displacement (MSD) calculation and the local structure and organization through radial distribution functions (RDFs).
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Thermodynamics
A. Alsabery, A. Hajjar, M. A. Sheremet, M. Ghalambaz, I Hashim
Summary: The analysis focuses on the computational study of nanosuspension forced convection in a horizontal wavy channel with heating from the upper wavy surface. The use of nanofluids and irregular channels can enhance energy transport and heat removal. Increasing Reynolds number leads to a narrowing of fluid tube within the channel and improvement of average velocity and Nusselt number, while higher channel waviness number results in increased average particle velocity and temperature.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Green & Sustainable Science & Technology
M. Shanmugapriya, R. Sundareswaran, P. Senthil Kumar, Gayathri Rangasamy
Summary: Nanoadditives are a type of heat transfer intensification approach used in heat exchangers to enhance the performance of industrial systems, electronic devices, and energy equipment by improving the thermal performance of regular fluids. The study found that magnetized ternary hybrid nanofluid has a higher heat transfer capability in the flow over a moving wedge, and ternary hybrid nanoparticles with blade shape have a higher tendency to enhance the rate of heat transfer.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2022)
Article
Mathematics, Applied
Sohail Nadeem, Salman Akhtar, Nevzat Akkurt, Anber Saleem, Shahah Almutairi, Hassan Ali Ghazwani
Summary: This study mathematically investigates the heat and mass transfer during the peristaltic flow of a non-Newtonian Jeffrey fluid inside an elliptic cross-section duct. The analysis considers constant heat absorption and provides a descriptive assessment of the heat and mass transfer. Exact solutions are obtained using a polynomial solution technique for the dimensionless partial differential equations in the problem. A purposeful graphical assessment is provided for the final mathematical results. Velocity and temperature profiles reach their highest values in the core region of the duct and gradually decrease towards the duct boundaries.
ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK
(2023)
Article
Thermodynamics
Xi-Wei Tian, Shu-Zhen Zhang, Chen Sun, Wei Wang
Summary: The objective of this study is to improve the heat transfer performance of cold plates with wavy channels used in Battery Thermal Management Systems (BTMSs). The study proposes a method based on parametric modeling to enhance design flexibility, allowing for the free construction of wavy geometry. The construction of Horizontal Wavy Channels (HWC) and Radial Wavy Channels (RWC) are optimized using the NSGA-II algorithm with the objective functions of overall thermal performance and temperature uniformity.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Environmental Sciences
Maryam Hasanpour, Siamak Motahari, Dengwei Jing, Mohammad Hatami
Summary: The study synthesized Cellulose/Zinc Oxide-x hybrid aerogel with various concentrations of Zn2+ ion using the hydrothermal method for organic pollutant removal. The results showed excellent photocatalytic degradation efficiency of methyl orange under UV irradiation with a degradation rate of 99.02% and mineralization rate of 51.68% under optimized conditions. The synthesized photocatalyst exhibited good recyclability and easy separation from the aqueous solution.
Article
Physics, Multidisciplinary
Qusay Rasheed Al-Amir, Hameed K. Hamzah, Farooq H. Ali, Seyfettin Bayraktar, Muslum Arici, Mohammad Hatami
Summary: This paper presents numerical investigations on the magnetohydrodynamics forced convection of CNT-water nanofluid inside a square enclosure with one inlet and one outlet. The results reveal that the bottom wall of the enclosure is very sensitive to the elastic wall, while the Nusselt number on the top wall increases with the Hartmann number.
EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS
(2022)
Article
Chemistry, Physical
Jinghua Li, Mohammad Hatami, Yalong Huang, Bing Luo, Dengwei Jing, Lijing Ma
Summary: This study developed a facile method to prepare noble-metal-free photocatalysts by in situ hybridization of non-noble metal copper nanoparticles with TiO2. Cu nanoparticles greatly enhanced the photocatalytic hydrogen production rate, providing a low-cost and high-efficiency approach for practical application of emerging technology.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Geological
Mohammad Hatami, David Bayless, Alireza Sarvestani
Summary: This study investigates the simultaneous effects of gas slippage and poroelasticity on shale permeability using a series of experiments and a developed permeability model. The results show that the evolution of permeability is influenced by gas slippage and the effective stress coefficient. The pore size and the variation of gas viscosity with pressure and temperature also play important roles in gas slippage.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Chemistry, Physical
Fei Xue, Haochen Wu, Yuting Liu, Moya Min, Mohammad Hatami, Naixu Li, Maochang Liu
Summary: An ideal composite model made of CuS nanosheet and g-C3N4 was constructed, utilizing the dual photo-chemical effect and photothermal effect. The optimized CN/CuS composite exhibited significantly improved photocatalytic performance, attributed to the inherent characteristics of CuS as a photochemical component. The contribution of photothermal effect in enhancing water photosplitting was experimentally verified.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Multidisciplinary
Abderrahmane Aissa, Mohammad Hatami, M. A. Medebber, Sahraoui Haroun, Sameh E. Ahmed, Sahnoun Mohammed
Summary: In this paper, the MHD free convection flow of non-Newtonian nanoliquid inside a halved annulus enclosure considering a constant heat flux is analyzed using the finite element method. The effects of different parameters on the flow behavior and heat transfer performance are investigated.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Multidisciplinary Sciences
A. B. Vishalakshi, U. S. Mahabaleshwar, M. Hatami
Summary: This study investigates the flow of Marangoni convection Magneto hydrodynamics Casson fluid with carbon nanotubes under the effects of transpiration and radiation. Analytical solutions for the temperature and concentration profiles are obtained, and the influence of different parameters is discussed using graphical arrangements.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Multidisciplinary
K. Ghadamkheir, J. Zareei, Xiaohu Yang, M. Hatami
Summary: Diesel engines play an important role in transportation, but the main issues are the high levels of CO2 and soot emissions. A numerical study found that blending oxymethylene ether with diesel can improve engine performance and reduce emissions. The results showed that using oxymethylene ether can significantly decrease soot and NOx emissions by over 80%, and also reduce CO2 emissions by approximately 66%.
ALEXANDRIA ENGINEERING JOURNAL
(2023)
Article
Engineering, Multidisciplinary
Mohammad Hatami, Abbas Heydari
Summary: This research conducted experimental and numerical studies on the geometric optimization of a tangential swirl burner for a steel pipe industry company, LGE. By optimizing three different parameters using the Response Surface Methodology, the study achieved improvements in temperature, NOx and CO emissions through multi-objective optimization. The modeling results showed good accuracy with a maximum error of 2.42% for temperature, confirming the effectiveness of the applied method.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Psychology, Clinical
Solaleh Zamani, Jafar Hasani, Mohammad Hatami, Eman Tadros
Summary: The literature suggests that alexithymia is linked to marital burnout, leading to couples seeking support and potential divorce. This study explores the mediation of emotion dysregulation in the relationship between attachment styles and alexithymia, using a structural equation model. Results show that emotion dysregulation partially mediates the relationship, explaining a high variance in alexithymia (R-2 = 0.86).
JOURNAL OF COUPLE & RELATIONSHIP THERAPY-INNOVATIONS IN CLINICAL AND EDUCATIONAL INTERVENTIONS
(2023)
Article
Thermodynamics
Xiaobin Jiang, Mohammad Hatami, Aissa Abderrahmane, Obai Younis, Basim M. Makhdoum, Kamel Guedri
Summary: This study simulates the three-dimensional flow of Fe3O4/MWCNT-water hybrid nanofluid in a 3D cubic enclosure filled with a porous medium. The effects of various flow parameters and the presence of rotating cylinders and a wavy wall are investigated. The results show that higher angular speed of the cylinders and lower Hartmann number enhance heat transfer and Nusselt number, while entropy production is mainly due to heat transfer but is also influenced by fluid-friction and magneto effects.
APPLIED THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Mushtaq F. Almensoury, Basil Mahdi Al-Srayyih, Qusay Rasheed Al-Amir, Hameed K. Hamzah, Azher M. Abed, Farooq H. Ali, Seyfettin Bayraktar, Muesluem Arici, Mohammad Hatami
Summary: This study investigates the effects of four vibrating cylinders on the mixed convection and entropy generation of water flowing inside a ventilated enclosure. The results show that the presence and vibration of the cylinders can increase heat transfer, with the vibration in the horizontal direction being more effective. The entropy generation mainly occurs at the center of the enclosure. Furthermore, a direct relationship between heat transfer and the Reynolds and Richardson numbers is observed, with the critical vibration frequency and amplitude being 4 Hz and 0.05L and 0.075L respectively.
NUMERICAL HEAT TRANSFER PART A-APPLICATIONS
(2023)
Article
Multidisciplinary Sciences
G. P. Vanitha, U. S. Mahabaleshwar, M. Hatami, Xiaohu Yang
Summary: The present study aims to predict the flow characteristics of a micropolar liquid infused with ternary nanoparticles across a stretching/shrinking surface under the impact of chemical reactions and radiation. The flow, heat and mass transfer characteristics are analyzed, including the suspension of three dissimilarly shaped nanoparticles (copper oxide, graphene, and copper nanotubes) in H2O. The governing equations are derived and transformed into ordinary differential equations for analysis. The impact of skin friction is also considered in this study, and the characteristics of the micropolar liquid are presented through graphs.
SCIENTIFIC REPORTS
(2023)
Article
Materials Science, Multidisciplinary
U. S. Mahabaleshwar, T. Anusha, M. Hatami
Summary: This paper investigates the unsteady stagnation-point flow of a hybrid nanofluid over a stretching/shrinking sheet embedded in a porous medium with mass transpiration and chemical reactions. Analytical solutions for velocity and concentration profiles are obtained, and the effects of different physical parameters on the flow field are examined.
FDMP-FLUID DYNAMICS & MATERIALS PROCESSING
(2023)
Article
Chemistry, Multidisciplinary
Hameed K. Hamzah, Doaa F. Kareem, Saba Y. Ahmed, Farroq H. Ali, Mohammad Hatami
Summary: In this study, a numerical investigation was conducted to analyze the steady-state heatlines visualization, fluid flow, and heat transfer inside a square enclosure with the presence of a magnetic field. The results showed that the absolute value of the maximum stream function decreased with increasing Hartmann number and decreasing Darcy number. Heatlines and isothermal lines increased with increasing Darcy number. The average Nusselt number increased with increasing Rayleigh number and decreasing Hartmann number.
IRANIAN JOURNAL OF CHEMISTRY & CHEMICAL ENGINEERING-INTERNATIONAL ENGLISH EDITION
(2022)
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)
