Article
Thermodynamics
Aidar Hayrullin, Alex Sinyavin, Aigul Haibullina, Vladimir Ilyin
Summary: Foam-like materials with large specific surface area and complex structure promote flow turbulence and are useful for heat transfer. This study experimentally investigated the hydraulic and heat transfer characteristics of polyurethane foam inserts in a rectangular channel, showing that although the heat transfer intensity of PUF samples is lower than that of metal foams, a significant heat transfer enhancement up to 7 times can still be achieved compared to an empty channel.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Khurram Altaf, Adeel Tariq, Syed Waqar Ahmad, Ghulam Hussain, T. A. H. Ratlamwala, Hafiz Muhammad Ali
Summary: This study focuses on optimizing the thermal performance of heatsinks by implementing slots while maintaining the pressure drop. Computational Fluid Dynamics analysis shows that the optimized heatsinks exhibit better thermal performance without compromising the pressure drop.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Aitor Amatriain, Corrado Gargiulo, Gonzalo Rubio
Summary: A multiscale model for open-cell foams has been developed for characterization of heat exchangers. It is applicable to a wide range of materials, cell sizes, and porosities. The model accurately predicts the thermal performance of macroscopic systems based on microscopic geometries and parameters.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Polymer Science
Ehsan Rostami-Tapeh-Esmaeil, Sahar Shojaei, Denis Rodrigue
Summary: Uniform and graded polyolefin elastomer (POE) foams were prepared using a single-step technology, and the effects of molding temperature on the foams' morphology, mechanical properties, and thermal conductivity were investigated. The results showed that the foam's properties can be easily controlled by the cellular structure, and graded samples are more interesting for thermal insulation applications.
Article
Thermodynamics
Nesrine Zahi, Asma Alkabsh, Feriel Bouhjar, Lotfi Derbali
Summary: In this study, a computational model is developed to investigate the fluid flow and heat transfer in a two-dimensional horizontal cylinder filled with an open-cell metal foam block. The results show that the behavior of both hydrodynamics and heat transfer can be controlled by adjusting the porosity, size, and other parameters of the metal foam.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Materials Science, Multidisciplinary
Jun Wei Chua, Xinwei Li, Tao Li, Beng Wah Chua, Xiang Yu, Wei Zhai
Summary: This study successfully produced functionally graded foam made of Inconel 625 superalloy and proposed methods to improve sound absorption performance. The sound absorption effects can be customized by various permutations of foam layers, adjusting the thickness proportion of pore sizes, and increasing the number of distinct pore sizes used. This study provides valuable insights and mathematical guidelines in the design and manufacturing of functionally graded metallic foam for specific applications.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Thermodynamics
Saeed Vahidifar, Seyedhadi Banihashemi
Summary: Researchers have conducted numerous studies on active and passive methods to improve thermal performance and increase heat transfer in internal flows. Different geometries and configurations of turbulators have been proposed for optimal performance in heat exchangers. However, there is limited research on turbulators with equal obstruction inside the tube and aerodynamic geometry. This study investigates the effect of stimulating the boundary layer of the internal flow on heat transfer and flow characteristics, using a pipe with ring-shaped turbulators and equal blocking area.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Nemat Mashoofi Maleki, Mohammad Ameri, Ramin Haghighi Khoshkhoo
Summary: This study investigates a novel heat transfer enhancement method named electromagnetic vibration (EMV) method. The experimental results indicate that increasing vibration frequency can improve the heat transfer coefficient, and the oscillator with the geometry of strip has better thermal performance. Meanwhile, the numerical analysis shows that the EMV method can achieve high heat transfer augmentation.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Ramtin Fattahi, Maysam Saidi
Summary: This paper investigates the impact of curved shape fin heights on the performance of open microchannel heat sinks. By employing three-dimensional simulation, different geometries of rectangular, plano-convex, and plano-concave fins are examined. Various parameters including fin height, curve range coefficient, Reynolds number, and heat flux are analyzed. The results show that the Nusselt number of the rectangular fin is lower than the two curved shapes. Additionally, the Nusselt number of the plano-concave is greater than the plano-convex at lower fin heights, while the opposite is true at higher fin heights.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Jian Song, Fei Liu, Yi Sui, Dalei Jing
Summary: This study numerically investigates the hydraulic and thermal performances of trapezoidal microchannel heat sinks, revealing that pressure drop increases with decreasing small-to-large end width ratio. Only TMCHS configurations with PCPFLI and RCCFLI show improved thermal performances as the ratio decreases, with lower thermal resistance and more uniform temperature distribution. The TMCHS with RCCFLI configuration exhibits the best overall thermal performance among the six configurations studied.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Thermodynamics
Zihao Zheng, Yuan Yi, Xiaohui Bai, Akira Nakayama
Summary: A new design concept of Functionally Graded Structure has been proposed for efficient heat exchangers, with optimized fin height distribution achieving higher heat transfer performance. Functionally graded structures are more effective in dissipating heat to the environment compared to conventional structures.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Engineering, Multidisciplinary
Samer M. Abdulhaleem, Isam Mejbel Abed, Nejla Mahjoub Said, Azher M. Abed
Summary: This study investigated the effect of hybrid nanofluids Al2O3-SiO2/water and Al2O3-CuO/water on heat transfer in parabolic solar collectors. The Nusselt number and pressure drop generally increase with increasing total volume fraction. The performance coefficient does not show a uniform trend compared to the percentage of nanoparticles composition in hybrid nanofluids.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2023)
Article
Thermodynamics
Yacine Khetib, Khaled Sedraoui, Abdellataif Gari
Summary: This study numerically investigated a micro-pin-fin heat sink to improve its cooling capability and productivity. It found that the RS configuration had the maximum heat transfer while also yielding the maximum pressure drop.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Energy & Fuels
Junfei Guo, Pan Wei, Xinyu Huang, Xiaohu Yang, Ya-Ling He, Bengt Sunden
Summary: Metal foam is adopted to improve the low thermal conductivity of traditional thermal energy storage systems and increase solar energy conversion efficiency. This study investigated a vertical thermal energy storage tube embedded with metallic foam with radial gradient porosity and pore density. It was found that positive radial porosity arrangement shortened the melting duration by 11.2% and negative arrangement prolonged it by 16.8%. Positive porosity increased temperature uniformity by 4.9% while negative porosity decreased it by 15.1%. Positive and negative gradient pore density respectively increased temperature uniformity by 15.1% and 16.7%.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Mechanics
Nima Movahedi, Matej Vesenjak, Irina Belova, Graeme E. Murch, Thomas Fiedler
Summary: This study explores the dynamic compression behavior and mechanical properties of functionally-graded metal syntactic foams under different particle types and aspect ratios. The findings suggest that uniform metal syntactic foams with lower aspect ratios exhibit higher overall strength, and different particle types show varying responses at higher loading velocities. The dynamic deformation of FG-MSFs originates in the weaker layer and transitions to a stronger layer at higher strains, affecting the stress-strain response.
COMPOSITE STRUCTURES
(2021)
Article
Energy & Fuels
Assunta Andreozzi, Marcello Iasiello, Claudio Tucci
Summary: This study conducts a thermal analysis of a square phase change material (PCM) for solar Organic Rankine Cycle (ORC), considering different boundary conditions and showing the significant impact of natural convection effects on temperature values and stored energy.
Article
Thermodynamics
Marcello Iasiello, Mauro Mameli, Sauro Filippeschi, Nicola Bianco
Summary: This study investigates the thermal conductivity performance of phase change materials and aluminum foams under different conditions, showing good agreement between experiments and numerical simulations. The results indicate that reducing porosity significantly reduces melting time, while PPI and orientation changes have minimal effects on the melting front.
APPLIED THERMAL ENGINEERING
(2021)
Article
Computer Science, Interdisciplinary Applications
Assunta Andreozzi, Luca Brunese, Marcello Iasiello, Claudio Tucci, Giuseppe Peter Vanoli
Summary: This paper analyzes the effects of pulsating heat in tumor tissue under hyperthermia, finding that pulsatile heat protocols can decrease maximum temperature and achieve the same treatment outcomes as non-pulsating heat sources.
COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE
(2021)
Article
Chemistry, Physical
Gerardo Maria Mauro, Marcello Iasiello, Nicola Bianco, Wilson K. S. Chiu, Vincenzo Naso
Summary: This paper proposes a comprehensive optimization framework for the design of graded foam-filled channels, which can enhance thermal performance of heat sinks. The study investigates both mono- and multi-objective optimizations to find the optimal tradeoffs between heat transfer enhancement and pressure drop reduction. The results provide valuable insights and guidelines for the thermal design of graded foam-filled channels.
Article
Engineering, Chemical
Assunta Andreozzi, Luca Brunese, Marcello Iasiello, Claudio Tucci, Giuseppe Peter Vanoli
Summary: This study models the process of thermal ablation treatment for hepatocellular carcinoma tumors and proposes a new damage-controlled protocol. Numerical solutions show that the new protocol can achieve complete ablation faster and reduce tissue temperature at the tumor rim.
Article
Thermodynamics
Nicola Bianco, Andrea Fragnito, Marcello Iasiello, Gerardo Maria Mauro, Luigi Mongibello
Summary: Latent heat thermal storage based on phase change material (PCM) in shell-and-tube heat exchangers can reduce power consumption of air conditioning systems. By optimizing the charging/discharging time of PCM and the operating conditions of the chiller, better performance can be achieved. Experimental validation shows that the optimal solution leads to a reduction in the inlet temperature by 1.25℃ and a maximum utilization of PCM by 40% of the initial amount. Further optimization results in a shell diameter reduction of 12 cm to exploit 72% of the PCM potential.
APPLIED THERMAL ENGINEERING
(2022)
Article
Energy & Fuels
Lorenzo Gragnaniello, Marcello Iasiello, Gerardo Maria Mauro
Summary: This study addresses the optimization of a heat sink for the thermal management of a Peltier-cell-based biomedical refrigerator. A brute-force multi-objective optimization of an impinging-flow finned heat sink is carried out to minimize thermal resistance, weight, and pressure drop. The results provide a range of optimal solutions and offer a practical tool for the optimal design of such devices to the final user.
Article
Energy & Fuels
Augusto Cavargna, Luigi Mongibello, Marcello Iasiello, Nicola Bianco
Summary: This study focuses on the simulation and implementation of a small-scale PCM-based condenser in a portable cooling system. The PCM is integrated in the condenser to absorb the heat released during condensation, eliminating the need for external heat transfer. The objective is to develop and validate a numerical model that can simulate both the refrigerant fluid and the PCM thermofluid dynamics. A commercial solver was used for the numerical model implementation, and experimental tests were conducted to validate the simulations. The results show good agreement between the numerical and experimental data.
Article
Energy & Fuels
Nicola Bianco, Andrea Fragnito, Marcello Iasiello, Gerardo Maria Mauro, Luigi Mongibello
Summary: Choosing the right phase change material (PCM) is crucial for the effectiveness of thermal energy storage (TES) systems. Factors such as latent heat, stability, and melting point determine the choice of PCM for a specific application. However, subcooling phenomena can affect the energy storage/release and accuracy of modeling, highlighting the importance of understanding its effects on PCM performance.
Article
Thermodynamics
Nicola Bianco, Martina Caliano, Andrea Fragnito, Marcello Iasiello, Gerardo Maria Mauro, Luigi Mongibello
Summary: This paper presents a numerical analysis of a hybrid latent heat thermal energy storage (LHTES) system using micro-encapsulated phase change material (MEPCM) in cylindrical modules integrated into a water tank, aiming to enhance storage efficiency and reduce energy usage of a water-chiller system.
Article
Biotechnology & Applied Microbiology
Marcello Iasiello, Assunta Andreozzi, Nicola Bianco, Kambiz Vafai
Summary: Heart arrhythmia is caused by abnormal electrical conduction through the myocardium, which can be treated with pulsed heat to avoid damage to healthy tissue or electrical issues. This study uses pulsed heat to regulate temperature fields during radiofrequency cardiac ablation. A three-dimensional model is developed for the myocardium, catheter, and blood flow. Different pulsed conditions are tested to determine if a reasonable ablation zone can be obtained without undesired temperature peaks.
BIOENGINEERING-BASEL
(2023)
Article
Thermodynamics
Abolfazl NematpourKeshteli, Marcello Iasiello, Giuseppe Langella, Nicola Bianco
Summary: This paper simulates the simultaneous harvesting and storing of solar thermal energy using a lobed double-pipe heat exchanger with Phase Change Materials. The study shows that a six-lobed surface reduces the charging and discharging time by 18.32% compared to a one-lobe one. By combining all the enhancement techniques and using the lowest investigated porosities for the foam, the charging and discharging times are reduced by 66.68% and 81.62%, respectively, compared to Case A with pure RT82, with the main contribution coming from metal foam inclusion.
APPLIED THERMAL ENGINEERING
(2023)
Review
Energy & Fuels
Assunta Andreozzi, Pietro Asinari, Antonio Barletta, Vincenzo Bianco, Johan Augusto Bocanegra, Pedro Vayssiere Brandao, Bernardo Buonomo, Roberta Cappabianca, Michele Celli, Eliodoro Chiavazzo, Paolo De Angelis, Andrea Diani, Sauro Filippeschi, Marcello Iasiello, Oronzio Manca, Sergio Nardini, Carlo Nonino, Luisa Rossetto
Summary: In the past decade, innovative methods for the design of heating, cooling, and heat storage devices have focused on the use of nanofluids, metal foams, and phase change materials (PCMs). A network of nine Italian universities has achieved significant results by collaboratively researching and evaluating the enhancement in heat transfer and thermal performance through the combined use of these materials.
Article
Thermodynamics
Abolfazl NematpourKeshteli, Marcello Iasiello, Giuseppe Langella, Nicola Bianco
Summary: This paper presents solutions to improve the thermal performances of paraffin as a Phase Change Material (PCM) in solar flat-plate collector systems for domestic and industrial solar applications. These solutions involve using aluminum foams with high porosity, nanoparticles, and modifications to the geometry. Numerical predictions show that the addition of nanoparticles and metal foams can significantly reduce the melting and solidification time of the PCM, with metal foams playing a more important role in improving cycling times.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Biotechnology & Applied Microbiology
Andrea Cafarchio, Marcello Iasiello, Maria Chiara Brunese, Giampiero Francica, Aldo Rocca, Assunta Andreozzi
Summary: This study investigated the in vivo ablation characteristics of a microwave ablation antenna in the livers of humans with tumors. The results showed a worse correlation between ablation volume and energy delivered in vivo compared to ex vivo, likely due to the absence of perfusion.
BIOENGINEERING-BASEL
(2023)
Article
Thermodynamics
Yunxia Ma, Fei Liu, Honggang Pan, Hongjian Zhang, Shuxia Yan, Ailing Zhang
Summary: This paper proposes a dynamically tunable and switchable perfect infrared absorber that exhibits excellent electrical regulation performance and high absorptance. The absorption mechanism is explained using a multiple interference model, and it is proven to be polarization insensitive.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
F. J. dos Santos, G. S. M. Martins, M. Strobel, L. Beckedorff, K. V. de Paiva, J. L. G. Oliveira
Summary: This study investigates the effects of inlet conditions and plate's features on the thermal-flow performance of a gasket plate heat exchanger (GPHE) and assesses the impact of a modified tightening distance on its performance. No systematic study on the combined effects of inlet conditions and assembly accuracy on GPHE performance has been conducted before.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Alok K. Ray, Dibakar Rakshit, K. Ravi Kumar, Hal Gurgenci
Summary: The low thermal conductivity of phase change materials limits the heat transfer rate and application of latent heat storage systems. This numerical study examines the impact of two passive heat transfer enhancement techniques on the thermal performance of a latent heat storage system. The results show that the orientation and position of the heat transfer fluid tube have significant effects on the charging duration, while the discharging duration remains unchanged. The combined effect of orientation and eccentricity reduces the charging duration, but increases the discharging duration compared to the concentric domain.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Yalu Han, Yanlong Wang, Chenyang Liu, Xinmin Hu, Yin An, Zhengcai Li, Jiaxun Jiang, Lizhi Du
Summary: This paper investigates the calculation method of thermal conductivity in NAPLs-contaminated soils. By establishing NAPLs-contaminated soil models and using the Lattice Boltzmann Method (LBM) for calculation, an optimized three-dimensional model with high computational accuracy and efficiency is obtained. The study also finds that saturation and Nz parameters have a significant impact on calculation time, while the thermal conductivity of the two-dimensional model is more sensitive to anisotropy. The influence of porosity and NAPLs content on thermal conductivity should be considered during in-situ thermal desorption.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Mostafa Taha, Song Zhao, Aymeric Lamorlette, Jean-Louis Consalvi, Pierre Boivin
Summary: For the first time, large-eddy simulations (LES) of the near-field region of large-scale fire plumes were performed using a pressure-based Lattice Boltzmann method (LBM) with low-Mach number approximation. The simulations showed quantitative agreement with experimental data and were consistent with previously-published numerical studies. The study demonstrated the computational efficiency of the proposed LBM solver in tackling fire-induced flows, suggesting LBMs as a good alternative candidate for modeling fire-related problems.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Weixin Zhang, Yehang Xie, Yuqiang Ding, Zhao Liu, Zhenping Feng
Summary: This study investigated the impact of upstream slot leakage on the endwall film cooling characteristics of turbine blades. Pressure Sensitive Paint (PSP) technology was used to measure the film cooling characteristics, and numerical analysis was conducted to evaluate the aerodynamic performance. It was found that increasing the mass flow ratio of the upstream slot enhanced film cooling, decreased aerodynamic losses, and reduced the strength of passage vortex. However, reducing the distance between the slot and the blade leading edge only enhanced film cooling without affecting the leakage coverage area.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Rui Zhang, Zhen-lei Li, Yan-sheng Zhang, Dong Chen, Guo Yuan
Summary: This study discusses the heat transfer behavior of different jet forms on steel tubes. The results show that the annular jet performs better in terms of cooling intensity and uniformity. The cooling performances of the two jet forms are similar when the steel tube size is small. Therefore, the planar jet can be considered for smaller diameters due to its simplicity, low cost, and convenience in application.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
A. R. Khoei, A. M. Orvati Movaffagh, A. Rezaei Sameti
Summary: This paper presents a comprehensive study on the thermo-mechanical characteristics of oxide-coated aluminum nano-powder. It is found that the thermal conductivity of oxide-coated aluminum nano-powder is significantly lower than that of the bulk aluminum, and it is affected by the density and temperature.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Yanjin Wang, Jintao Xiong, Lingyu Chen, Zhihai Lv, Qian Wang
Summary: A solar radiation transfer model for spray cooling double skin facade (SC-DSF) is proposed in this study. The model is validated by experimental results and various influence factors are analyzed. The effectiveness of adjusting droplet coverage rate and size is also evaluated.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Bostjan Zajec, Blaz Mikuz, Anil Kumar Basavaraj, Marko Matkovic, Matej Tekavcic, Martin Draksler, Leon Cizelj, Bostjan Koncar
Summary: We have developed an advanced experimental setup to investigate flow and heat transfer in an annular channel. The setup allows heat transfer measurements and flow visualization using a temperature-controlled inner tube. Measurements can be conducted in both single-phase and two-phase flow regimes. The setup ensures a uniform velocity field in the annular channel using specially designed inlet and outlet headers. The inner copper tube is heated by water and contains turbulators for enhanced heat transfer and thermocouples for temperature measurement. A three-dimensional conjugate heat transfer CFD model has been developed and validated to accurately estimate heat losses in the setup. This study demonstrates the importance of numerical simulations in improving the interpretation of complex experimental results.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Weijie Chen, Ke Wang, Yongqing Wang, Shantung Tu, Zunchao Liu, Huijuan Su
Summary: In this study, a novel gradient porosity transpiration cooling plate structure (GP-TCPS) is proposed to alleviate heat transfer deterioration caused by non-uniform temperature distribution in transpiration cooling plate structure (TCPS). Computational fluid dynamics (CFD) and response surface method (RSM) were used for qualitative and quantitative analysis of the flow and heat transfer of GP-TCPS. The optimized structure of GP-TCPS significantly improves temperature uniformity, injection pressure, and average cooling efficiency compared to traditional TCPS.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
R. Essam, A. Elsaid, W. K. Zahra
Summary: This study presents a novel bioheat model for simulating heat transfer in skin tissue. The model offers an improved representation of thermal dynamics in the skin and has been validated using numerical solutions and experimental measurements. The study highlights the importance of incorporating vascular inlet parameters and thermal relaxation effects in the thermal profile, and suggests potential applications in thermal therapy and wound healing.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Dongbo Shi, Tao Xu, Zifeng Chen, Di Zhang, Yonghui Xie
Summary: The cooling structure design of turbine blades is crucial for the safety and reliability of the gas turbine set. This research investigates different arrangement schemes, including dimple/protrusion arrangements, to enhance the cooling performance. The results show that the arrangement scheme with both passes arranged by dimples has the best comprehensive thermal performance.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Emrehan Guersoy, Hayati Kadir Pazarlioglu, Mehmet Guerdal, Engin Gedik, Kamil Arslan
Summary: The thermo-hydraulic performance of Al2O3/H2O nanofluid with different nanoparticle shapes flowing in a sudden expansion tube with variable sudden expansion inclination angles and elliptical dimpled fins with different diameters were numerically investigated. The results showed that the nanoparticle shapes, sudden expansion inclination angles, and elliptical dimpled fin have significant impact on the thermo-hydraulic performance. This study reveals the novelty and importance of these factors in the research.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Rukun Hu, Xinyu Huang, Xinyu Gao, Liu Lu, Xiaohu Yang, Bengt Sund
Summary: This study examines the impact of applying bottom cross-cut on PCM's spatial distribution in a horizontal LHTES unit using numerical simulation. The findings show that bottom cross-cut can improve the heat storage rate and natural convection heat transfer gain.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)