Article
Engineering, Chemical
Xu Ma, Yindong Song, Yang Wang, Shouguang Yao, Kambiz Vafai
Summary: In this study, novel hybrid nanoparticles were prepared using Ag modified functionalized GNP, and the boiling heat transfer properties of the nanofluids were investigated. The GNP-Ag hybrid nanofluids with a weight concentration of 0.001% exhibited the best heat transfer performance, with improved structural modification and wetting properties playing a crucial role in enhancing the heat transfer.
Article
Engineering, Chemical
Xu Ma, Yindong Song, Yang Wang, Yuni Zhang, Jingya Xu, Shouguang Yao, Kambiz Vafai
Summary: This study focuses on functionalizing graphene nanoplatelets to improve hydrophobicity while maintaining good thermal properties, and preparing hybrid nanofluids for enhanced heat transfer. Novel GNP-Fe3O4 hybrid nanoparticles with high purity and hydrophilic functional groups were prepared. The addition of metal or non-metal nanoparticles improved the heat transfer characteristics of nanofluids. Experimental results showed significant enhancement in heat transfer properties compared to deionized water, with GNP-Fe3O4 + Al2O3 and GNP-Fe3O4 + SiO2 hybrid nanofluids exhibiting the best heat transfer effects.
Article
Engineering, Mechanical
Marthe Braut, Luis Gonzalez-Fernandez, Anna Kosinska, Yaroslav Grosu, Pawel Kosinski
Summary: This research found that nanofluids containing 1.33 wt% TiO2 have erosive effects on copper and plastic surfaces, while causing nanoparticle deposition on rubber surfaces.
Article
Chemistry, Multidisciplinary
Wagd Ajeeb, S. M. Sohel Murshed
Summary: This paper presents an experimental investigation on the heat transfer characteristics of new and recycled Alumina nanofluids in a pool boiling system. The study evaluates the performance and reusability of these nanofluids for long-term applications. The results show significant enhancements in critical heat flux and burnout heat flux for the nanofluids, indicating their potential for heat transfer systems.
Article
Nuclear Science & Technology
T. Hirai, L. Bao, V. Barabash, Ph. Chappuis, R. Eaton, F. Escourbiac, M. Merola, R. Mitteau, R. Raffray, J. Linke, Th. Loewenhoff, D. Dorow-Gerspach, G. Pintsuk, M. Wirtz, D. Boomstra, C. J. Klaassen, A. Magielsen, J. Chen, P. Wang
Summary: Eight mock-ups imitating ITER Enhanced Heat Flux First Wall panel were tested for thermal fatigue after neutron irradiation at two dose levels, approximately 0.1 dpa and approximately 0.5 dpa. All mock-ups successfully endured repeated thermal fatigue loads of up to 4.7 MW/m2. The test results confirmed the performance of the mock-ups, particularly the design and manufacturing technologies of the two domestic agencies responsible for series production.
FUSION ENGINEERING AND DESIGN
(2023)
Article
Thermodynamics
Heng Chen, Dmitry Bokov, Supat Chupradit, Maboud Hekmatifar, Mustafa Z. Mahmoud, Roozbeh Sabetvand, Jinying Duan, Davood Toghraie
Summary: By using molecular dynamics simulations, this study investigated the combustion process in nanofluids consisting of oxygen molecules and aluminum nanoparticles from an atomic point of view. The research identified factors affecting the combustion process and created a phase change in the simulated atomic structure. By changing parameters such as initial temperature, pressure, and external heat flux, optimal conditions for combustion and heat transfer processes were established, leading to convergences in physical quantities like flux and combustion time.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Sayantan Mukherjee, Purna Chandra Mishra, Paritosh Chaudhuri
Summary: The experimental investigation showed significant improvements in boiling heat transfer coefficient and critical heat flux at a mass fraction of 0.1% for Al2O3 and TiO2 nanoparticles in water. An increase in mass fraction improved the surface wettability of nanofluids and reduced the surface roughness of the boiling surface. Al2O3-water nanofluids exhibited better boiling performance compared to TiO2-water nanofluids.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Nanoscience & Nanotechnology
Junsheng Hou, Junjie Wu, Hongqiang Chen, Lei Huang, Li Ma, Xiong Zhao, Zihan Ding, Yonghai Zhang, Jiabin Fang, Jinjia Wei, Satoshi Watanabe, Nanjing Hao
Summary: A facile microfluidic synthesis strategy is developed to prepare highly stable and size-controllable silica nanofluids, enhancing the heat transfer efficiency and providing new insights for the rational design of two-phase cooling nano-systems.
MATERIALS TODAY NANO
(2023)
Review
Chemistry, Multidisciplinary
Muhammad Asim, Farooq Riaz Siddiqui
Summary: In recent years, advancements in high-heat-flux devices have led to significant heat dissipation challenges that cannot be solved by traditional thermal fluids. This review discusses the hydrothermal properties and heat transfer characteristics of the next-generation thermal fluid, hybrid nanofluid, and presents its potential for spray-cooling high-heat-flux devices.
Article
Chemistry, Multidisciplinary
Wagd Ajeeb, S. M. Sohel Murshed
Summary: This study investigates the pool boiling heat transfer performance of hybrid and mono nanofluids containing boron nitride and silicon dioxide nanoparticles. The results show that both types of nanofluids demonstrate improvements in critical heat flux and burnout heat flux compared to the base fluid, with the highest enhancement observed in a boron nitride-based mono nanofluid.
Article
Nuclear Science & Technology
Vojtech Smolik, Miroslav Gleitz, Pavel Zacha, Slavomir Entler
Summary: The paper discusses the commissioning of an inductive heater through numerical simulation of inductive heating in a hypervapotron sample and test channel. The purpose is to develop a HEFEL loop for studying high heat flux cooling channels in fusion devices, with particular emphasis on the Box Scraper hypervapotron channel geometry. The induction heating serves to simulate conditions in the first wall of a tokamak, and the numerical simulation and thermohydraulic model are crucial for commissioning the HEFEL loop. ANSYS Maxwell 3D and ANSYS Fluent are used to optimize induction heating and achieve the highest heat fluxes.
FUSION ENGINEERING AND DESIGN
(2023)
Article
Energy & Fuels
Bruno Pinheiro Serrao, Kyung Mo Kim, Juliana Pacheco Duarte
Summary: Nanofluid (NF) pool boiling experiments have been widely conducted to understand the effects of nanoparticles (NP) on boiling heat transfer and critical heat flux (CHF). However, the physical mechanisms behind the improvements in CHF are still inconclusive due to the complexity of the experimental data and surface characteristics. This study focuses on using machine learning (ML) regressor models to create a more accurate model for predicting NF pool boiling CHF based on pressure, substrate thermal effusivity, NP size, concentration, and effusivity.
Article
Computer Science, Information Systems
Faizan Ahmed, Waqar Ahmed Khan, Jamal Nayfeh
Summary: This study aimed to enhance the performance of a heat pump by using copper and alumina nanofluids, which resulted in a significant improvement in the coefficient of performance, especially with the highest volume fraction of 5%. The findings suggest that utilizing nanofluids can greatly benefit performance enhancement in thermal systems like heat pumps.
CMC-COMPUTERS MATERIALS & CONTINUA
(2021)
Article
Engineering, Mechanical
Suwarno Suwarno, Abdul Jabar I'jazurrohman, Fajar Dwi Yudanto, Vivien S. Djanali
Summary: This study reports a new failure mechanism of waste heat boiler (WHB) tubes, which failed due to excessive oxidation. A computational model reveals the flow recirculation that leads to excessive oxidation. This study is of great importance for developing heat exchanger designs and exploring damage mechanisms.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Mathematics, Interdisciplinary Applications
A. A. Avramenko, I. Shevchuk, A. Tyrinov
Summary: This article presents an analysis of the convective instability of a nanofluid in a vertical porous cylindrical microchannel with slip boundary conditions. It was found that an increase in the porosity of the medium promotes stabilization, while the conditions for the onset of convection are decisively influenced by the thermal conductivity of nanoparticles.
CHAOS SOLITONS & FRACTALS
(2021)
Article
Thermodynamics
Francois Chantriaux, Theo Quenouille, Nguyen Anh Khoa Doan, Nedunchezhian Swaminathan, Yannis Hardalupas, Amkp Taylor
Summary: Multi-scale analysis of turbulence-flame interaction was conducted using experimental data, revealing that vortex stretching mechanism is minimally influenced by premixed flame and the tangential strain rate imparted by eddies is mainly contributed by eddies with length scales larger than about 20 times the flame thickness.
COMBUSTION AND FLAME
(2022)
Article
Food Science & Technology
D. Bikos, G. Samaras, P. Cann, M. Masen, Y. Hardalupas, M. N. Charalambides, C. Hartmann, J. German, J. Vieira
Summary: This study quantified the mechanical, thermal and tribological behavior of chocolate materials with different porosity levels and found that micro-aeration affects fracture stresses, melting speed, and friction coefficient of chocolate, resulting in a softer, less sticky chocolate that melts quickly inside the mouth. This research utilizes an innovative multidisciplinary approach to link chocolate structure, material properties, and sensory perception, providing a powerful design tool for controlling sensory attributes in specific chocolate compositions.
FOOD STRUCTURE-NETHERLANDS
(2022)
Article
Food Science & Technology
D. Bikos, G. Samaras, M. N. Charalambides, P. Cann, M. Masen, C. Hartmann, J. Vieira, A. Sergis, Y. Hardalupas
Summary: Micro-aeration modifies the microstructure of chocolate, creating a third phase layer consisting of cocoa butter with higher melting properties. A multiscale computational model is developed to simulate the structural changes and estimate the thermal properties of micro-aerated chocolate. The study reveals a complex thermal mechanism that controls the behavior of micro-aerated chocolate during melting and solidification, resulting in a slower heat transfer.
INNOVATIVE FOOD SCIENCE & EMERGING TECHNOLOGIES
(2023)
Article
Mechanics
Anjan Goswami, Yannis Hardalupas
Summary: This study investigates the dynamics of the simultaneous impact of two droplets on a dry substrate. A new micro-controlled droplet generator is developed to release two equally sized water droplets simultaneously on-demand. The impact processes for both deposition and splashing of the liquid sheet are analyzed. Simultaneous high-speed imaging provides a quantification of the three-dimensional structure of the sheet morphology, including the temporal evolution of various features.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Materials Science, Multidisciplinary
Dimitrios Bikos, Georgios Samaras, Philippa Cann, Marc Masen, Yannis Hardalupas, Joselio Vieira, Christoph Hartmann, Peter Huthwaite, Bo Lan, Maria N. Charalambides
Summary: This study aims to determine the mechanical properties of chocolate with different levels of micro-aeration under varying modes of deformation. Destructive mechanical experiments are conducted to calculate the Young's modulus, yield, and fracture stress of chocolate. The results show that the Young's modulus of chocolate varies significantly among different mechanical experiments but becomes negligible for the 15% micro-aerated chocolate, suggesting the role of micro-pores in affecting the mechanical behavior of chocolate.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Thermodynamics
Tianyi Wang, Yushuai Liu, Chaoxu Chen, Yannis Hardalupas
Summary: This study applies the technique of two-photon excitation (TPE), planar laser induced fluorescence (PLIF), and optical connectivity (OC) to capture the instantaneous geometry of a liquid jet during atomisation. It demonstrates that a nanosecond pulse laser can excite two-photon fluorescence in a dye-doped water jet. The combination of TPE-PLIF and TPE-OC eliminates the limitations of individual techniques and allows for the quantification of the cross-section structures on the liquid jet surface during atomisation.
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2023)
Article
Thermodynamics
A. Sergis, Y. Hardalupas, K. Flinders, D. Hancock, T. Barrett
Summary: This study investigates the morphological and thermal effects of nanoparticle deposition processes on heating surfaces under high heat fluxes. The experiments reveal that nanosuspensions deteriorate cooling performance by forming a porous nanoparticle layer. Increasing nanoparticle concentration helps mitigate the negative thermal effects. The deposited porous layers have the potential to extend critical heat flux in industrial processes.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Mechanics
Tianyi Wang, Yannis Hardalupas
Summary: Liquid jet in crossflow (LJIC) is a process where a high-speed gas crossflow deforms and shears a continuous liquid flow into tiny droplets. This study quantifies the liquid surface motion of LJIC during the primary breakup process, which has not been quantified due to the optical limitation close to the nozzle exit.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2023)
Article
Thermodynamics
M. Iqbal, K. Kouloulias, A. Sergis, Y. Hardalupas
Summary: Nanofluids, colloidal suspensions of nanoparticles and heat transfer fluids, have shown potential for enhanced heat transport in various applications. This study investigates the reported enhancements in thermal conductivity and their alignment with theoretical predictions using a rigorous mathematical analysis method. The results suggest that low nanoparticle concentrations and the use of pH control for electrostatic stabilization, rather than surfactants for steric stabilization, are likely to result in anomalous effects. The findings highlight the importance of understanding the underlying mechanisms of heat transfer in nanofluid preparation.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Engineering, Mechanical
Georgios Samaras, Dimitrios Bikos, Christos Skamniotis, Philippa Cann, Marc Masen, Yannis Hardalupas, Joselio Vieira, Christoph Hartmann, Maria Charalambides
Summary: This article discusses the critical role of structural breakdown of foods in the oral cavity and proposes a computer simulation-based design method to establish the relationship between food mechanical properties and oral behavior. The article introduces a non-local damage approach that overcomes numerical parameter dependency and provides mesh independent results consistent with experimental findings, which is valuable in studying food structure-function relationships.
EXTREME MECHANICS LETTERS
(2023)
Article
Physics, Fluids & Plasmas
Dimitrios Kolokotronis, Srikrishna Sahu, Yannis Hardalupas, Alex M. K. P. Taylor, Akira Arioka
Summary: This study aims to visualize and quantify the relationship between cavitation and liquid flow field in three different injector models. It was found that although bulk cavitation was present, there was no swirling flow structure in the mean flow field at the nozzle exit. However, analysis of the instantaneous liquid velocity data showed that the most energetic mode corresponded to the expected swirling flow structure when bulk cavitation occurred.
Article
Biochemistry & Molecular Biology
D. Bikos, G. Samaras, M. N. Charalambides, P. Cann, M. Masen, C. Hartmann, J. Vieira, A. Sergis, Y. Hardalupas
Summary: This study accurately predicts the temporal and spatial evolution of temperature in chocolate samples using a multiscale finite element model. Experimental and numerical results show that the rate of heat transfer is reduced in micro-aerated chocolate, possibly due to micro-pores acting as thermal barriers.
