Article
Thermodynamics
Mohammad Parhizi, Ankur Jain
Summary: This work presents an approximate analytical method for heat transfer problems involving solid-liquid phase change, showing improved accuracy compared to classical methods even at large values of Stefan number. The method can also be applied to solve similar mass transfer problems with a chemical reaction front. It improves theoretical understanding of phase change heat transfer in the presence of advection.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Thermodynamics
Mohammad Parhizi, Long Zhou, Ankur Jain
Summary: Theoretical modeling of solid-liquid phase change processes is important for energy storage and thermal management. This paper presents a theoretical analysis of phase change in a system comprising a phase change material (PCM) and a multi-layer wall. The analysis takes into account thermal conduction through the multi-layer wall and considers thermal contact resistance between wall layers and between the wall and PCM. The results improve the understanding of phase change heat transfer processes and are particularly relevant for relatively thick, thermally insulating walls over relatively short time periods.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Emad Hasrati, Ankur Jain
Summary: This paper presents an approximate eigenfunction expansion-based analysis of inwards phase change propagation in a cylindrical phase change material (PCM) encapsulated in a multilayer annular wall. The model considers imperfect thermal contact between layers and accurately predicts the transient temperature distribution and the evolution of the phase change front. The results are validated against experimental and numerical data, demonstrating the potential applications of this method in various fields.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Mathematics
Marianito R. Rodrigo, Ngamta Thamwattana
Summary: This paper introduces a unified approach for solving fixed and moving boundary problems for the one-dimensional heat equation, by embedding the initial-boundary value problem into an initial value problem on the real line with arbitrary functions. Exact analytical solutions for some moving boundary problems are provided.
Article
Thermodynamics
Ankur Jain, Mohammad Parhizi
Summary: This paper presents a theoretical analysis of phase change heat transfer in a spherical PCM with an encapsulant layer, considering the effect of thermal contact resistance. The results show that the model accurately describes the phase change heat transfer process and agrees well with numerical simulations. The study analyzes the influence of encapsulant thickness, thermal properties, and thermal contact resistance on phase change propagation.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Review
Green & Sustainable Science & Technology
Saad Akhtar, Minghan Xu, Mohammaderfan Mohit, Agus P. Sasmito
Summary: This article reviews various mathematical approaches used to model droplet freezing at different stages. It analyzes the application of these approaches in pharmaceutical, food, energy storage, meteorology, and process industry fields. The review concludes that while significant progress has been made in macro-scale modeling of droplet solidification, there is a need for further development of holistic mathematical models that incorporate nucleation dynamics.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2023)
Article
Physics, Multidisciplinary
Waleed Hamali, Musawa Yahya Almusawa
Summary: The numerical procedure based on Galerkin technique was used to model the freezing process of water inside an enclosure with elliptic and triangular cold surfaces. The results showed that the freezing time can be reduced by increasing the volume of nanoparticles or the shape factor, and this effect can be further enhanced by increasing the concentration of alumina.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Thermodynamics
Zoubida Haddad, Farida Iachachene, Faiza Zidouni, Hakan F. Oztop
Summary: The study examines the effects of a magnetic field on melting and solidification processes in an isosceles triangular cavity using numerical methods. Results show that the direction of the magnetic field significantly impacts fluid flow stability, with longer melting times observed when the field is horizontal or vertical. Additionally, the influence of the magnetic field peaks during an intermediate stage of melting, while solidification is independent of magnetic field direction and magnitude.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Energy & Fuels
Houssem Eddine Abdellatif, Ahmed Belaadi, Hassan Alshahrani, Mohammad K. A. Khan, Mostefa Bourchak
Summary: Phase-change materials (PCMs) are promising for heat storage due to their ability to hold and release a large amount of energy during the phase shift process. This study investigated the melting and solidification behavior of PCMs with different aspect ratios (L/D) in five tanks, finding that the tank shape significantly influenced the heat flux of water. Increasing the aspect ratio (L/D) led to higher thermal stratification and faster melting or solidification rates, except for a special case. However, there are limits to this increase to avoid adverse effects.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Engineering, Chemical
Christoph Reichl, Svenja Both, Philipp Mascherbauer, Johann Emhofer
Summary: This study compares the implemented solidification and melting model with the apparent heat capacity method in Ansys Fluent, and compares with analytical solution and experimental data. The importance of temperature-dependent material properties in modeling is demonstrated, and an evaluation of the two methods is provided.
Article
Thermodynamics
Fabricio J. C. Pena, Marcelo J. S. de Lemos
Summary: Thermite reactions, commonly used in welding, material synthesis, and pyrotechnics, have recently been investigated for plugging depleted oil wells. This study numerically simulates a Fe2O3/Al thermite reaction using the open-source software OpenFOAM. The numerical results show good agreement with experimental data for temperature levels and indicate thermal losses near the thermite-steel interface, leading to incomplete melting of alumina during the reaction.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Energy & Fuels
Amin Shahsavar, Abbas Goodarzi, Pouyan Talebizadehsardari, Mulsum Arici
Summary: This study investigated the phase change process in a double-pipe latent heat storage system with sinusoidal wavy fins, which resulted in significant efficiency improvements. The best wave profile was determined to have a wave-amplitude of 2 mm and a wavelength of 1 mm. Additionally, the characteristics of the water flow in the system were found to impact performance.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Review
Thermodynamics
M. Rogowski, R. Andrzejczyk
Summary: This article provides an overview of recent studies on heat transfer enhancement methods in phase change material-based latent heat thermal energy storage systems, with a specific focus on the utilization of fins and coils. The influence of various geometrical and material parameters on the melting and solidification processes, as well as the orientation of the heat transfer surface within the storage tank, is discussed. The article also examines the use of different phase change materials based on their melting temperature.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Green & Sustainable Science & Technology
Jerzy Woloszyn, Krystian Szopa
Summary: The objective of this research is to design a new latent heat thermal energy storage system with improved thermal conductivity and reduced melting and solidification time. Numerical experiments comparing different designs show that the proposed system significantly reduces melting and solidification time compared to traditional systems, and achieves the highest efficiency.
Article
Thermodynamics
Jasim M. Mahdi, Azher M. Abed, Hussein Alawai Al-Saaidi, Nidhal Ben Khedher, Raed Khalid Ibrahim, Mouldi Ben Amara
Summary: This study investigates the effectiveness of a novel central return tube in enhancing heat transfer and accelerating phase transition in a thermal storage system using phase-changing materials (PCMs). The results demonstrate that the return tube significantly improves thermal response and storage performance of the PCM system.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
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)