Article
Thermodynamics
Ji-Hwan Hwang, Dong-Wook Jerng
Summary: This study investigated the effect of helium on condensation heat transfer using both experimental and theoretical analyses. The results showed that the helium effect was stronger than predicted at low helium content.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2022)
Review
Thermodynamics
Jian Xu, Yi Wang, Ren Yang, Wanlong Liu, Hongwei Wu, Yulong Ding, Yongliang Li
Summary: This paper reviews the state-of-the-art knowledge of boiling heat transfer in binary mixtures, emphasizing the advantages of using mixtures in the heating and cooling industry. It provides a summary of important published articles and limitations to existing studies, aiming to guide future research and innovations in this thermal management technique.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Mechanics
Christos Tantos, Stylianos Varoutis, Christian Day
Summary: In this study, the problem of heat conduction through binary mixtures of non-vibrating polyatomic gases is investigated by considering the internal degrees of freedom of gas molecules. The results show that there is a linear variation in the relative deviation between monatomic and polyatomic heat fluxes when the difference in molecular masses of the species is small, while a nonlinear behavior is observed for gases with significantly different molecular masses. The study also demonstrates that polyatomic gas mixtures cannot be accurately modeled using monatomic modeling.
Article
Chemistry, Physical
He Zhao, Dan Zhao, Sid Becker
Summary: This study presents a numerical analysis of the performances of counterflow double-channel micro-combustors in terms of the first and second laws. The results indicate that the double-channel configuration offers improved uniformity of wall temperature compared to the single channel configuration, with the oval shaped thread configuration achieving the highest wall temperature and uniformity. Increasing the inlet velocity leads to a higher average wall temperature and slightly reduced uniformity. Chemical reaction is found to be the main contributor to entropy generation. Regardless of the thread shapes, the second law efficiency remains just below 0.5. Thread shapes have no significant influence on the combustor exergy. The use of a blended ammonia-hydrogen fuel results in a slightly higher average wall temperature and less uniform wall temperature.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Kerem Bozkurt, Levent Akyalcin, Signe Kjelstrup
Summary: This study investigates the impact of the combined gas diffusion layer and membrane on the thermal diffusion coefficient and water transport in polymer electrolyte membrane fuel cells. The results show that the sign of the coefficient depends on the materials used. Hydrophobic layers, such as Teflon-coated and microporous layer-containing gas diffusion layers, have positive coefficients, while those without microporous layers have negative coefficients. The activation energy of the thermal diffusion coefficient suggests that water movement is facilitated by activated jumps. It is concluded that hydrophobic layers significantly enhance water and heat transport away from the cathode, emphasizing the importance of reversible heat transfer in fuel cell studies.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Review
Energy & Fuels
Fulong Zhao, Yiguo Mei, Tiebo Liang, Bin Wang, Hao Jing, Weixiong Chen
Summary: This paper investigates the heat transfer characteristics of helium-xenon gas mixtures for space nuclear power sources. It finds that existing research results lack experimental data and systematic studies on enhanced heat transfer technologies. More experiments and detailed analysis are urgently needed to develop an enhanced heat transfer theory for helium-xenon heat exchangers.
Article
Chemistry, Physical
Oliver R. Gittus, Fernando Bresme
Summary: Temperature gradients induce mass separation in mixtures in a process called thermodiffusion, and the Soret coefficient is used to quantify this phenomenon. The existence of minima in the Soret coefficient of aqueous solutions at specific salt concentrations has been controversial, but recent experiments and simulations have provided evidence for it. However, it is still unknown what causes this minimum and whether it is also present in non-aqueous liquid mixtures. In this study, we demonstrate the generality of minima in the Soret coefficient by observing it in liquid mixtures of non-polar liquids modeled as Lennard-Jones mixtures. This minimum is found to originate from a coincident minimum in the thermodynamic factor, indicating a maximization of non-ideality mixing conditions. We propose that the atomic coordination structure of the mixtures is responsible for this effect.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Physics, Multidisciplinary
Samriti Dhiman, Tanya Sharma, Kuldeep Singh, Kottakkaran S. Nisar, Rakesh Kumar, C. S. K. Raju
Summary: This study introduces the novel concept of thermal and solutal stratifications in a nanofluid's non-orthogonal stagnation point flow and solves the problem using numerical methods. The results show that solutal stratification has a greater impact on mass transfer and reduces the skin friction coefficient.
EUROPEAN PHYSICAL JOURNAL PLUS
(2023)
Article
Thermodynamics
Aloisi Somer, Andressa Novatski, Francisco Carlos Serbena, Ervin Kaminski Lenzi
Summary: This study analyzes the heat propagation in non-homogeneous solids by considering fractional differential operators and examining the effects of superdiffusion and subdiffusion on the photoacoustic signal generated by light sources.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Thermodynamics
Kimihide Odagiri, Kieran Wolk, Stefano Cappucci, Stefano Morellina, Scott Roberts, Andre Pate, Benjamin Furst, Eric Sunada, Takuro Daimaru
Summary: This paper presents a three-dimensional heat transfer analysis of a flat-plate oscillating heat pipe (OHP) and reveals the combined effect of thermo-hydraulic phenomena and thermal diffusion in the OHP structure. Surface roughness and liquid film thickness in the channel were found to have an impact on the operating temperature distribution.
APPLIED THERMAL ENGINEERING
(2021)
Article
Energy & Fuels
Anil Can Turkmen, Mayken Espinoza-Andaluz, Cenk Celik, Bengt Sunden, Hakan Serhad Soyhan
Summary: The purpose of this study is to evaluate the thermal conductivity of gas diffusion layers (GDLs) under different operating temperatures. A completely designed measurement apparatus is used to evaluate the thermal conductivities of five different GDL samples. The amount of catalyst material in the GDLs is also taken into consideration. Based on the measurements, thermal conductivity correlations as a function of the operating temperature are proposed. These correlations consider a 95% confidence interval and show good predictivity. The study proposes thermal conductivity coefficient functions for GDLs, which can be used to determine the thermal properties of fuel cells in a temperature range of 20 degrees C to 80 degrees C.
Article
Energy & Fuels
Xichuan Cai, Shiquan Shan, Qi Zhang, Jingwei Zhao, Zhijun Zhou
Summary: The new high-pressure Weighted-Sum-of-Gray-Gases (WSGG) model developed in this study accurately predicts the radiative heat transfer process of gas mixtures in pulverized coal gasification plants, and is applicable under different gas partial pressure conditions.
Review
Chemistry, Multidisciplinary
Ali Almertejy, Muhammad M. Rashid, Naser Ali, Salah Almurtaji
Summary: This article introduces the methods of using nanofluids to improve gas turbine efficiency, including experimental and numerical studies. The general principles governing turbines are described, and commonly used types of heat exchangers are introduced. The application of nanofluids in heat exchangers is reviewed.
Article
Thermodynamics
A. Sukhanovskii, A. Evgrafova
Summary: The study shows that in developed convective flow, the boundary layer thickness is almost independent of the layer height, and is mainly defined by the applied temperature difference and physical properties of the fluid.
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2021)
Article
Engineering, Mechanical
Aloisi Somer, Andressa Novatski, Gerson Kniphoff da Cruz, Claudia Bonardi Kniphoff da Cruz, Francisco Carlos Serbena, Ervin Kaminski Lenzi
Summary: Obtaining thermal parameters based on the analysis of the amplitude or phase of the photoacoustic signal from photothermal measurements is useful. This study investigates the discrepancy between experimentally measured amplitude and phase and the expected theoretical result from the classical model for AISI 316 samples. The results show inconsistent thermal parameters obtained from individual amplitude analysis compared to phase analysis, and this study aims to propose a simultaneous analysis of both amplitude and phase to obtain a unique value for the thermal parameters. Additionally, fractional models were used to improve the fit of experimental data and provide results close to the expected thermal diffusivity value.
NONLINEAR DYNAMICS
(2023)
Article
Mathematics, Applied
E. Barbera, C. Curro, G. Valenti
PHYSICA D-NONLINEAR PHENOMENA
(2015)
Article
Physics, Multidisciplinary
Elvira Barbera, Francesca Brini
Article
Acoustics
Elvira Barbera, Giovanna Valenti
Article
Mathematics, Applied
Elvira Barbera, Francesca Brini
ACTA APPLICANDAE MATHEMATICAE
(2014)
Article
Mathematics, Applied
Elvira Barbera, Francesca Brini, Masaru Sugiyama
ACTA APPLICANDAE MATHEMATICAE
(2014)
Article
Mechanics
Elvira Barbera, Francesca Brini
Article
Mechanics
Elvira Barbera, Francesca Brini
Article
Physics, Fluids & Plasmas
Elvira Barbera, Giancarlo Consolo, Giovanna Valenti
Article
Physics, Multidisciplinary
Takashi Arima, Elvira Barbera, Francesca Brini, Masaru Sugiyama
Article
Mathematical & Computational Biology
Elvira Barbera
INTERNATIONAL JOURNAL OF BIOMATHEMATICS
(2020)
Article
Mathematics, Applied
Elvira Barbera, Francesca Brini
RICERCHE DI MATEMATICA
(2019)
Proceedings Paper
Thermodynamics
Elvira Barbera, Francesca Brini
NONEQUILIBRIUM THERMODYNAMICS AND STATISTICAL PHYSICS: FROM RATIONAL MODELING TO ITS APPLICATIONS
(2018)
Article
Multidisciplinary Sciences
Elvira Barbera, Francesca Brini
ATTI ACCADEMIA PELORITANA DEI PERICOLANTI-CLASSE DI SCIENZE FISICHE MATEMATICHE E NATURALI
(2017)
Article
Mathematics, Applied
E. Barbera, C. Curro, G. Valenti
RICERCHE DI MATEMATICA
(2017)
Article
Mathematical & Computational Biology
Elvira Barbera, Giancarlo Consolo, Giovanna Valenti
MATHEMATICAL BIOSCIENCES AND ENGINEERING
(2015)
Article
Physics, Multidisciplinary
Tinggui Chen, Baizhan Xia, Dejie Yu, Chuanxing Bi
Summary: This study proposes a gradient phononic crystal structure for enhanced acoustic sensing. By breaking the symmetry of the PC structure, topologically protected edge states are introduced, resulting in topological acoustic rainbow trapping. The robustness and enhancement properties are verified numerically and experimentally.
