Article
Green & Sustainable Science & Technology
Wael Al-Kouz, Abderrahmane Aissa, S. Suriya Uma Devi, M. Prakash, Lioua Kolsi, Hazim Moria, Wasim Jamshed, Obai Younis
Summary: This study presents a comprehensive numerical analysis of entropy production and mixed convection in a rotating cavity filled with a phase change material. The results indicate that the rotational speed and position of the cylinder can significantly affect the convective heat transfer and melting process.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2022)
Article
Energy & Fuels
Ammar I. I. Alsabery, Mohammed J. J. Alshukri, Nasr A. A. Jabbar, Adel A. A. Eidan, Ishak Hashim
Summary: The generation of entropy and mixed convection in a nanofluid-filled 3D wavy tank containing a rotating cylinder is investigated. The effects of Richardson number, nanoparticle volume fraction, and number of oscillations on heat transfer enhancement are studied through numerical simulations using the FEM. The results show that increasing the nanoparticle volume fraction can enhance heat transfer for low values of the Richardson number and oscillation.
Article
Multidisciplinary Sciences
Hameed K. Hamzah, Farooq H. Ali, M. Hatami, D. Jing, Mohammed Y. Jabbar
Summary: Numerical Galerkin Finite Element Method (GFEM) was used to study the conjugate heat-transfer of a rotating cylinder in Fe3O4-water nanofluid, showing significant effects of parameters such as nanoparticles volume fraction and Hartmann numbers on the heat transfer performance.
SCIENTIFIC REPORTS
(2021)
Article
Thermodynamics
Wasim Jamshed, Mohamed R. Eid, Syed M. Hussain, Aissa Abderrahmane, Rabia Safdar, Obai Younis, Amjad Ali Pasha
Summary: This study investigates heat transmission and stable mixed convective flow in a ventilated porous enclosed space with a heated elliptic inner cylinder filled with MWCNT/CMC nanofluid. The numerical findings show that the average Nusselt number increases with higher Richardson number and porosity ratio.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Yang Zhang, Haitao Lin, Rishabh Chaturvedi, Pradeep Kumar Singh, Ibrahim B. Mansir, KePing Zhang, Javid Alhoee
Summary: Using natural phenomena like free convection and modern nanostructures called NEPCM can improve heat transfer in lid-driven problems. This study simulated mixed convection of ethylene glycol and NEPCM in a lid-driven cavity with a rotating cylinder to assess the influence of Grashof number, cylinder speed, and NEPCM concentration on heat transfer characteristics. The results showed that a 6% concentration of NEPCM increased the mean Nusselt number by 41.7%, while the cylinder speed increased it by 38.7%. Additionally, an optimum concentration of 4% was observed for a Grashof number of 104.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Rumman Hossain, A. K. Azad, Md Jahid Hasan, M. M. Rahman
Summary: This study conducted a numerical analysis of thermal radiation in a square enclosure with a semicircular heater and a sliding lid. The results showed that increasing radiation intensity and dimensionless time improves fluid velocity, pressure gradient, and temperature gradient, but decreases the heat transfer rate of the semicircular heater.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Thermodynamics
Laith M. Jasim, Hudhaifa Hamzah, Cetin Canpolat, Besir Sahin
Summary: This study presents a numerical solution for the influence of an inner rotating adiabatic cylinder on mixed convection of hybrid nanofluid inside a vented cavity. The study explores the effects of various parameters on energy transport and presents the results through qualitative and quantitative figures.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Chemistry, Multidisciplinary
Apichit Maneengam, Tarek Bouzennada, Aissa Abderrahmane, Kaouther Ghachem, Lioua Kolsi, Obai Younis, Kamel Guedri, Wajaree Weera
Summary: A numerical study was conducted to analyze the effects of several factors on heat transfer, flow behavior, and entropy generation in a hybrid nanofluid within a rotating inner tube. The results indicate that increasing the nanoparticle volume fraction, Darcy number, and velocity of the inner tube enhances heat transfer. Additionally, these factors have a significant influence on entropy generation.
Article
Engineering, Multidisciplinary
Mohammad Mokaddes Ali, Rowsanara Akhter, Md. Abdul Alim
Summary: The study investigated mixed convection in a nanofluid filled cavity, showing that the variations in length and speed of the rotating flat plate significantly affect flow and thermal fields. Additionally, nanoparticle concentration and magnetic field strength play a role in heat transfer performance.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Engineering, Mechanical
Hudhaifa Hamzah, Cetin Canpolat, Laith M. Jasim, Besir Sahin
Summary: In this study, the hydrothermal behavior and entropy generation of a heated cylinder in a vented cavity between two oppositely rotating cylinders were numerically investigated using the finite volume technique. The results showed that the optimal thermal performance criterion was achieved at low Reynolds number regardless of the position of the counter-rotating cylinders.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Engineering, Multidisciplinary
Rumman Hossain, A. K. Azad, Md Jahid Hasan, M. M. Rahman
Summary: This study numerically explores the time-dependent thermophysical characteristics of multiwalet carbon nanotubes in kerosene oil-based nanofluids, considering different concentrations. The results demonstrate that particle concentration significantly improves the thermophysical properties and heat transfer rate of the nanofluids.
ENGINEERING SCIENCE AND TECHNOLOGY-AN INTERNATIONAL JOURNAL-JESTECH
(2022)
Article
Multidisciplinary Sciences
Mohammed Hirpho
Summary: Numerical simulations were conducted on mixed convection of Casson fluid with a heated bottom wavy wall in a trapezoidal enclosure, investigating the effects of various non-dimensional parameters on flow and heat transfer. Results showed an increase in average Nusselt number with higher Richardson numbers for all Casson fluid parameters.
Article
Thermodynamics
Oktay Cicek, A. Filiz Baytas, A. Cihat Baytas
Summary: This study numerically analyzes the mixed convection and entropy generation in an annulus with a rotating heated inner cylinder for SWCNT-water nanofluid flow using the LTNE model. The findings indicate that buoyancy force and rotational effect significantly impact the strength of streamlines and isotherms. The addition of nanoparticles to the fluid decreases the minimum total entropy generation, suggesting a significant role for nanofluids in thermal design and heat transfer optimization.
INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW
(2021)
Article
Thermodynamics
Fatin M. Azizul, Ammar Alsabery, Ishak Hashim, Ali J. Chamkha
Summary: The study analyzes the heatline visualization of mixed convection mechanism and heat transfer in a double lid-driven square cavity with a heated wavy bottom surface. Various factors such as Reynolds number, Richardson number, Prandtl number, and number of oscillations significantly influence the convection mode. The number of oscillations has the most significant impact on streamlines and temperature distributions, while higher Reynolds and Prandtl numbers lead to increased heat transfer efficiency.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Physics, Multidisciplinary
Muhammad Shoaib Arif, Kamaleldin Abodayeh, Yasir Nawaz
Summary: This study extends a mathematical model of heat and mass transfer of fluid flow by incorporating the effect of non-linear mixed convection. The study utilizes the finite element method to solve boundary value problems and presents the results in graphs and tables. The findings of this research have important implications for future studies on heat transfer and fluid physics.
FRONTIERS IN PHYSICS
(2022)
Article
Energy & Fuels
Amin Shahsavar, Majid Jafari, Ighball Baniasad Askari, Fatih Selimefendigil
Summary: In this study, the influence of the number of ribs on the laminar forced convection flow of a silver/water-ethylene glycol nano-fluid in a rifled tube was investigated using the two-phase mixture model. The results showed that increasing the number of ribs was beneficial from the perspective of the first-law performance, but undesirable from the perspective of the second-law performance. It was also found that the rifled tube consistently outperformed the plain tube in terms of hydrothermal performance.
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
(2023)
Article
Engineering, Mechanical
Kotha Gangadhar, R. Edukondala Nayak, M. Venkata Subba Rao, Ali J. Chamkha
Summary: This paper examines the mechanism of radiative Walter's B nanofluid on a rotational cone under magnetic regime, including the theoretical and practical implications of time-dependent fluid flow caused by cone rotation in engineering and applied sciences, as well as the characteristics of thermophoresis, Brownian motion, and chemical reactions. Self-similar solutions are obtained and the numerical result of a reduced nonlinear system is obtained using the Runge-Kutta-Fehlberg fourth-fifth procedure. Comparisons with previously published material are made to verify the outcome. The conflicting influences of the Brownian motion parameter on heat and mass transfer rates, as well as temperature and concentration fields, are found. The presence of chemical reactions may be more beneficial in developing reaction processes.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART E-JOURNAL OF PROCESS MECHANICAL ENGINEERING
(2023)
Article
Engineering, Mechanical
K. Gangadhar, M. Venkata Subba Rao, D. Naga Bhargavi, Ali J. Chamkha
Summary: This research focuses on the hydrothermal characteristics of magnetohydrodynamic nanofluid flow over a slippery permeable bended surface. The study reveals that the concentration gradient of nanoparticles is affected by Brownian motion and thermophoretic force. The results also show that increasing magnetic parameter values decrease the velocity field magnitude and pressure in the boundary layer.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART E-JOURNAL OF PROCESS MECHANICAL ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Mehdi Ghalambaz, Mutabe Aljaghtham, Ali J. Chamkha, Abdelkader Abdullah, Ibrahim Mansir, Mohammad Ghalambaz
Summary: Embedding phase change material in metal foams can improve the heat transfer characteristics of a thermal energy storage device. This study investigates the melting heat transfer of phase change materials embedded in a heterogeneous metal foam and finds that increasing heterogeneity can enhance heat transfer rate and shorten melting time.
APPLIED MATHEMATICAL MODELLING
(2023)
Article
Engineering, Mechanical
Mehdi Ghalambaz, Mutabe Aljaghtham, Ali J. Chamkha, Abdelkader Abdullah, Abdullah Alshehri, Mohammad Ghalambaz
Summary: Metal foams with engineered local properties can enhance heat transfer in latent heat thermal energy storage (LHTES) units. However, the use of anisotropic metal foams for thermal energy storage has not been studied. This research mathematically modeled an anisotropic metal foam and simulated the phase transition behavior of a copper-coconut oil LHTES unit. The results showed that the anisotropic angle significantly affected the thermal energy storage power, and an optimum tilt angle of -45 or +45 along with zero anisotropic angle achieved the maximum charging power.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Thermodynamics
Dipak Kumar Mandal, Nirmalendu Biswas, Nirmal K. Manna, Rama Subba Reddy Gorla, Ali J. Chamkha
Summary: This study numerically examines the influence of various geometric parameters on the thermal performance of a novel W-shaped porous cavity undergoing hybrid nanofluid-based magnetohydrodynamic mixed convection. The results show that an increase in the bottom undulation height improves the thermal energy transfer despite the reduction of fluid volume. The overall thermal energy transport is improved by increasing Reynolds number, Richardson number, and Darcy number, while it is suppressed by increasing Hartmann number.
INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW
(2023)
Article
Engineering, Mechanical
Bhupendra Kumar Sharma, Umesh Khanduri, Nidhish K. Mishra, Ali J. Chamkha
Summary: This study numerically investigates the combined effects of Arrhenius activation and microorganisms on unsteady flow through a porous medium with thermophoresis and Brownian motion. The results have important implications for geothermal engineering, energy conversion, disposal of nuclear waste material, as well as applications in medical fields such as gene therapy and drug delivery systems.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART E-JOURNAL OF PROCESS MECHANICAL ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Ammar I. Alsabery, Muneer A. Ismael, Saleem K. Al-Hadraawy, Mohammad Ghalambaz, Ishak Hashim, Ali J. Chamkha
Summary: This research investigates the non-invasive hyperthermia therapy for abdominal aortic aneurysm (AAA), and analyzes the heat transfer and laminar flow in a heated AAA using an isothermal boundary condition. The study finds that reducing the viscous nature of blood in diseased vessels is recommended, as higher shear stress is observed for a higher index of the power-law fluid governing blood viscosity. Moreover, the study shows that the hyperthermia therapy becomes more effective when blood flows violently through the aortic, allowing for enhanced thermal energy transportation.
ALEXANDRIA ENGINEERING JOURNAL
(2023)
Article
Thermodynamics
Hussan Zeb, Hafiz A. Wahab, Umar Khan, Ali J. Chamkha
Summary: This study analyzed the characteristics of heat transfer in non-Newtonian ferrofluids produced by stretchable sheet and investigated the effects of Arrhenius activation energy and magnetic dipole. By applying a similarity ansatz and Runge-Kutta method, the computational solution for the governing system was determined. The influence of beneficial physical parameters on momentum, energy, and concentration profiles was shown through graphs.
Article
Thermodynamics
Shreedevi Kalyan, Ashwini Sharan, Ali J. Chamkha
Summary: This article examines the effect of heat and mass transfer flow of two immiscible Jeffrey fluids in a vertical channel. The impact of different physical parameters on the flow and distribution of velocity, temperature, and concentration is illustrated graphically.
Article
Energy & Fuels
Ammar I. I. Alsabery, Mohammed J. J. Alshukri, Nasr A. A. Jabbar, Adel A. A. Eidan, Ishak Hashim
Summary: The generation of entropy and mixed convection in a nanofluid-filled 3D wavy tank containing a rotating cylinder is investigated. The effects of Richardson number, nanoparticle volume fraction, and number of oscillations on heat transfer enhancement are studied through numerical simulations using the FEM. The results show that increasing the nanoparticle volume fraction can enhance heat transfer for low values of the Richardson number and oscillation.
Article
Thermodynamics
Alexander Nee, Bubryur Kim, Ali J. Chamkha
Summary: The present study focuses on the numerical analysis of heat transfer and fluid flow patterns in a three-dimensional problem formulation. A hybrid mathematical model is built, and the equations are solved using MATLAB. The results show that the emissivity of the vertical walls can be used as a tool to control thermal and flow behavior.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Energy & Fuels
Salah M. Salih, Ammar I. Alsabery, Ahmed K. Hussein, Muneer A. Ismael, Mohammad Ghalambaz, Ishak Hashim
Summary: The paper investigates the forced fluid flow within a horizontal channel containing two semi-cylinders and two flexible baffles. The melting of phase change material, convective and conductive heat transfers, and fluid-structure interaction are considered. The influential parameters are dimensionless time, elasticity modulus of the baffles, and Reynolds number. The results show that increasing Reynolds number and decreasing elasticity modulus lead to a decrease and increase, respectively, in the melting volume fraction.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Green & Sustainable Science & Technology
Naseer Abboodi Madlool, Mohammed J. Alshukri, Ammar I. Alsabery, Adel A. Eidan, Ishak Hashim
Summary: This paper investigates the convective heat transfer of laminar forced convection in a wavy channel. Numerical simulations using the finite element method are performed to obtain the 3D steady flow and heat transfer characteristics of Newtonian fluid. The study analyzes the effects of Reynolds number (10 < Re < 1000), number of oscillations (0 < N < 5), and wall amplitude (0.05 < A < 0.2) on the heat transfer. The results show that the average Nusselt number increases with the Reynolds number, and the number of oscillations and wall amplitude also affect the heat transfer.
INTERNATIONAL JOURNAL OF RENEWABLE ENERGY DEVELOPMENT-IJRED
(2023)
Article
Energy & Fuels
Puchanee Larpruenrudee, Doan Khai Do, Nick S. Bennett, Suvash C. Saha, Mohammad Ghalambaz, Mohammad S. Islam
Summary: Spray cooling technology offers efficient heat removal with low fluid volumes, and its application can be expanded with the help of research. This study investigates the impact of temperature and humidity conditions on spray cooling performance in six Australian cities, revealing that weather conditions, especially in summer, significantly influence the effectiveness of spray cooling.
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)
