Article
Thermodynamics
Ivan Belyaev, Petr Sardov, Ivan Melnikov, Peter Frick
Summary: Experimental and numerical studies show that temperature gradients in channel flows of liquid metals induce strong buoyancy forces that result in specific magnetic field structures affecting magneto-convective fluctuations. The existence of MCFs in this system is determined by properties of the liquid metal, channel configuration, and governing flow parameters.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Engineering, Mechanical
Nidhi Singh, Manish K. Khandelwal, Abhishek K. Sharma
Summary: The influence of applied magnetic field on the stability of liquid metal flows in a vertical channel is investigated. The results show that the stability of the flow increases with increasing strength of the magnetic field, while a decrease in thermal diffusivity provokes instability.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Nuclear Science & Technology
Wentao Guo, Horst-Michael Prasser
Summary: This study conducted DNS simulations on turbulent heat transfer in Poiseuille-Rayleigh-Benard flows with low Prandtl numbers. It was found that buoyancy plays a significant role in enhancing turbulence intensity, with larger scale circulation shrinking as Prandtl number increases. Additionally, temperature distributions become more uniform and mixing is more efficient with decreasing Prandtl numbers.
ANNALS OF NUCLEAR ENERGY
(2021)
Review
Thermodynamics
Yueguang Deng, Yi Jiang, Jing Liu
Summary: Low-melting-point liquid metal convection is a promising heat transfer technology in electronics thermal management and energy fields, with advantages such as high thermal conductivity, low melting point, and non-toxicity. This technology differs from traditional liquids in terms of heat transfer behavior and driving techniques. Although there is increasing research, a systematic description of gallium-based and bismuth-based liquid metal convection and its applications has not been reported yet.
APPLIED THERMAL ENGINEERING
(2021)
Article
Physics, Fluids & Plasmas
Andreas Bereczuk, Barbara Dietz, Jiongning Che, Jack Kuipers, Juan-Diego Urbina, Klaus Richter
Summary: This study delves into the universal correlations of scattering-matrix entries in nonstationary many-body scattering, demonstrating the emergence of chaotic dynamics in dynamical observables. By utilizing semiclassical theory, numerical simulations, and random-matrix ensembles, the calculations show excellent agreement with experimental measurements, even in extreme limits with few open channels relevant for electron quantum optics.
Article
Engineering, Electrical & Electronic
David Weik, Richard Nauber, Christian Kupsch, Lars Buettner, Juergen Czarske
Summary: This study introduces a novel method for estimating the uncertainty of a specific experimental setup according to the guide to the expression of uncertainty in measurement (GUM), based on an uncertainty model of the UIV processing. The proposed model provides optimal parameterization of UIV and velocity uncertainty for a specific experiment. Experimental validation demonstrates the feasibility and effectiveness of this method in MHD experiments.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Nuclear Science & Technology
Long Chen, Xuan Zheng, Mingjiu Ni
Summary: The Water-Cooled Lithium Lead (WCLL) breeding blanket is a proposed candidate option for European DEMO nuclear fusion reactor. PbLi, as the main material in the breeding blanket, has attracted significant attention. The interaction between Lorentz forces, intense buoyancy forces, and pressure-driven flow plays a crucial role in the magnetohydrodynamics and heat transfer phenomena. A 3-D DNS numerical simulation has been employed to replicate the dynamics of PbLi under the influence of the strong magnetic field and non-uniform heat source. The study provides insights into the heat transfer and optimization strategies for the BZ cooling system geometrical configurations.
FUSION ENGINEERING AND DESIGN
(2023)
Article
Thermodynamics
Adel Sahi, Messaoud Hamdi, Djamel Sadaoui, Bachir Meziani, Ouerdia Ourrad
Summary: This work presents a series of numerical results on the influence of an external magnetic field on mixed convection in a ventilated square cavity filled with a ferrofluid. Different scenarios were considered based on the magnetic Reynolds number values. Numerical simulations were conducted using the finite volume method and the SIMPLE algorithm with the QUICK scheme of Leonard. The results show different heat exchange enhancement and cooling effects of the heat source, depending on the magnetic field strength and direction, as well as the internal fluid behavior and constitution. The limitations of the low-Rm model in treating MHD flows are also highlighted.
NUMERICAL HEAT TRANSFER PART A-APPLICATIONS
(2023)
Article
Thermodynamics
Bilal Ahmed, T. Hayat, A. Alsaedi
Summary: The study investigated the effects of hybrid nanofluid on the peristaltic motion of MHD nanofluid, considering mixed convection, Hall parameter, and variable viscosity. The dimensionless equations were solved numerically, showing enhancements in temperature field for higher Hartman numbers and opposite trends for Hall effects. The inclusion of silver nanomaterial in copper nanofluid was found to facilitate heat transport characteristics.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Mechanics
M. S. Asmadi, R. Md. Kasmani, Z. Siri, H. Saleh
Summary: This study investigates natural convection heat transfer inside a U-shaped enclosure using copper-alumina/water hybrid nanofluid with various thermal profiles. The results show that constant heating profile has the best heat dissipation performance, while sinusoidal thermal profile performed the worst.
Article
Nuclear Science & Technology
Michiya Shimada, Jabir Al Salami, Kazuaki Hanada, Changhong Hu
Summary: The harsh heat load conditions on plasma-facing components in fusion reactors require the development of innovative plasma-facing components. Liquid metal PFCs with strong convection can enhance heat removal capability and resilience after transient phenomena.
JOURNAL OF FUSION ENERGY
(2023)
Article
Chemistry, Multidisciplinary
Houssem Laidoudi, Aissa Abderrahmane, Abdulkafi Mohammed Saeed, Kamel Guedri, Wajaree Weera, Obai Younis, Abed Mourad, Riadh Marzouki
Summary: This paper presents a numerical simulation of magneto-convection flow in a 3D chamber with specific permeability and a zigzag bottom wall. The study investigates the percentage of heat energy transferred between the nanofluid and the bottom wall under different criteria. The results show that natural convection dominates when the number of zigzags is 4, while forced convection dominates when the number of zigzags is 2.
Article
Engineering, Multidisciplinary
P. M. Patil, A. Shashikant, E. Momoniat
Summary: The study investigates combined convection nanoliquid flow involving three diffusive components along with a moving plate and magnetic field effects. The conservation equations are solved using Quasilinearization technique and finite difference method. The numerical simulation results show that the increase in the thermophoresis parameter Nt accelerates both the temperature profile and the nanoparticle Sherwood number, while the Brownian diffusion parameter Nb affects the temperature profile and nanoparticle Sherwood number differently.
AIN SHAMS ENGINEERING JOURNAL
(2021)
Article
Mechanics
Surabhi Nishad, Rama Bhargava, Ameeya Kumar Nayak, Bernhard Weigand
Summary: Energy flux analysis of power-law fluid is a novel contribution to recent developments in computational fluid dynamics. The study investigates the influence of double diffusive effect on unsteady two-dimensional flow inside a complex enclosure and proposes a method for optimizing heat transfer rate. By comparing the computational time and accuracy of the finite volume method and element-free Galerkin technique, the study obtains results such as streamlines, isotherms, isoconcentrations, average Nusselt number, Sherwood number, etc., and analyzes the impact of various parameters. In addition, the study employs a mesh-free approach, providing a new method for further analysis of elliptical/semi-elliptical structures.
Article
Energy & Fuels
Ciro Alberghi, Luigi Candido, Raffaella Testoni, Marco Utili, Massimo Zucchetti
Summary: Liquid metal breeding blankets are extensively studied in nuclear fusion, with systems like Water Cooled Lithium Lead (WCLL) and Dual Coolant Lithium Lead (DCLL) proposing intense transverse magnetic fields causing magnetohydrodynamic effects altering flow features and increasing pressure drops. The reliability of COMSOL Multiphysics for MHD models is tested with benchmark problems, showing good agreement with reference solutions and suggesting its suitability for studying liquid metal MHD problems in fusion power reactors.
Review
Physics, Multidisciplinary
P. G. Frick, D. D. Sokoloff, R. A. Stepanov
Summary: This review discusses the application of wavelet analysis in various fields, including astro-and geophysics, solar-terrestrial relations, climatology, medical physics, and laboratory hydrodynamic experiments. Wavelet analysis, as a natural extension of spectral analysis, has wide-ranging applications in dealing with complex nonstationary and spatially inhomogeneous systems.
Review
Mechanics
Oleg Zikanov, Ivan Belyaev, Yaroslav Listratov, Peter Frick, Nikita Razuvanov, Valentin Sviridov
Summary: An imposed strong magnetic field can suppress turbulence and alter the flow of an electrically conducting fluid, such as in the case of mixed convection flows in pipes and ducts. This has implications for the design of liquid-metal components in future nuclear fusion reactors. The review outlines the recent studies on flow transformation, highlighting key facts and open questions in this area, as well as discussing implications for fusion reactor technology and novel methods.
APPLIED MECHANICS REVIEWS
(2021)
Article
Thermodynamics
Ivan Belyaev, Petr Sardov, Ivan Melnikov, Peter Frick
Summary: Experimental and numerical studies show that temperature gradients in channel flows of liquid metals induce strong buoyancy forces that result in specific magnetic field structures affecting magneto-convective fluctuations. The existence of MCFs in this system is determined by properties of the liquid metal, channel configuration, and governing flow parameters.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Physics, Multidisciplinary
Odim Mendes, Kai Schneider, Margarete Oliveira Domingues, Marie Farge, Nalin Babulal Trivedi, Peter Frick, Natacha Nguyen van Yen
Summary: Investigation of electrodynamic effects considering South American features is crucial for understanding middle- to low-latitude space weather phenomena. A wavelet-based filtering method is applied to magnetic records to retrieve magnetic contributions related to geomagnetically induced currents (GIC). The wavelet analyses allow for a scale-dependent statistical characterization of magnetospheric-ionospheric processes affecting the Earth's surface. The proposed treatment provides a depurated GIC signal and establishes an objective-automatic computational method for GIC calculation treatment.
BRAZILIAN JOURNAL OF PHYSICS
(2022)
Article
Engineering, Mechanical
Vladislav Eltishchev, Gennadii Losev, Ilya Kolesnichenko, Peter Frick
Summary: This paper studies the circular surface wave (CSW) in liquid metal layers and confirms the occurrence of a stationary CSW regime when the forcing parameter exceeds a critical value. The CSW frequency and the amplitude of surface oscillations increase with increasing forcing.
EXPERIMENTS IN FLUIDS
(2022)
Article
Thermodynamics
Andrei Sukhanovskii, Vladimir Batalov, Rodion Stepanov, Peter Frick
Summary: The study examined the unsteady swirling flows generated by special diverters in closed toroidal channels with different curvatures. It was found that the formation of a swirling flow in a toroidal channel differs significantly from that in a straight cylindrical channel, as it is hindered by the increasing curvature.
HEAT TRANSFER ENGINEERING
(2023)
Article
Mechanics
Peter Frick, Sergei Mandrykin, Vladislav Eltishchev, Ilya Kolesnichenko
Summary: The study investigates the flow of liquid metal induced by electric current in a cylindrical cell, and finds that the ratio of electro-vortex flows and rotational forces affects the evolution of flow structure.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Ivan A. A. Belyaev, Ivan S. S. Mironov, Nikita A. A. Luchinkin, Yaroslav I. I. Listratov, Yuri B. B. Kolesnikov, Dmitry Kransov, Oleg Zikanov, Sergei Molokov
Summary: This study experimentally investigates the dynamics of a liquid metal flow in the form of a submerged round jet entering a square duct in the presence of a transverse magnetic field. The results show that the instability of the jet leads to high-amplitude fluctuations, and the flow structure and fluctuation properties are determined by the value of the Stuart number.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Physics, Multidisciplinary
I Abushzada, E. Yushkov, P. Frick, D. Sokoloff
Summary: This study investigates the small-scale magnetic energy generation in a turbulent velocity field using two different approaches. It is found that injecting a weak magnetic field leads to an exponential growth of magnetic energy, but the growth rates and magnetic energy spectra differ significantly between the two approaches, which can be attributed to model assumptions and unknown correlation time. The discussion of these contradictions suggests that the small-scale magnetic field generation is influenced by a specific spectral subrange.
Article
Thermodynamics
Ruslan Akhmedagaev, Oleg Zikanov, Ivan Belyaev, Yaroslav Listratov
Summary: This paper numerically analyzes mixed convection flows in a horizontal duct with a heated bottom wall and a magnetic field imposed in the horizontal transverse direction using the two-dimensional approximation. The effect of Reynolds, Hartmann, and Grashof numbers on the flow is studied, with a focus on the convection instability of quasi-two-dimensional states under strong magnetic fields. The study establishes the range of existence of such states and demonstrates that high-amplitude low-frequency magnetoconvective fluctuations are generated by the instability in a broad range of parameters, with their strength unaffected by increasing magnetic field. Good agreement with experimental data is found.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Mathematics, Applied
Peter Frick, Elena Popova, Andrei Sukhanovskii, Andrei Vasiliev
Summary: The free motions of a thermally insulating disc submerged in a liquid layer heated from below were experimentally studied. The appearance of large-scale vortices and their interaction with the disc resulted in complex two-dimensional motions. The dynamics of the disc was mainly influenced by the large-scale circulation, while small-scale convective cells had little effect on heat transport.
PHYSICA D-NONLINEAR PHENOMENA
(2023)
Article
Mechanics
S. Roehrborn, P. Juestel, P. Frick, V Galindo, Th Gundrum, F. Schindler, F. Stefani, R. Stepanov, T. Vogt
Summary: This paper mainly investigates the influence of tidal perturbations on the periodicity problem in solar dynamo and presents numerical simulation results.
MAGNETOHYDRODYNAMICS
(2022)
Article
Physics, Multidisciplinary
D. Krasnov, Ya Listratov, Yu Kolesnikov, I Belyaev, N. Pyatnitskaya, E. Sviridov, O. Zikanov
Summary: In this study, the flow generated by a planar jet at the inlet of a duct and influenced by a perpendicular magnetic field was analyzed through high-resolution numerical simulations at very high Reynolds and Hartmann numbers. The flow structure in the inlet area was found to be significantly altered, with the emergence of three new planar jets along the magnetic field lines. The downstream evolution of the flow involves the Kelvin-Helmholtz instability of the jets and a slow decay of the resulting quasi-two-dimensional turbulence.
Article
Engineering, Aerospace
A. R. Zabirov, I. A. Molotova, I. A. Belyaev, V. A. Ryazantsev, V. V. Yagov
Summary: The paper examines temperature measurement methods for cooling high-temperature bodies in liquids. Experimental studies show that external thermocouples can distort measured temperatures significantly, while using only a central thermocouple may result in temperature differences between the center and surface of the body. As the thermal conductivity of the sample decreases and its dimensions increase, temperature gradients become more pronounced, making it difficult to interpret the cooling process accurately.
THERMOPHYSICS AND AEROMECHANICS
(2021)
Article
Mechanics
I. A. Belyaev, N. Yu Pyatnitskaya, N. A. Luchinkin, D. Krasnov, Yu B. Kolesnikov, Ya Listratov, I. S. Mironov, O. Zikanov, E. Sviridov
Summary: This study experimentally investigates a liquid metal flat jet in a square duct under the influence of a transverse magnetic field, considering cases where the applied magnetic field is oriented parallel or perpendicular to the initial plane of the jet. By measuring signals of streamwise velocity at different locations, the study aims to determine average velocity profiles and spatial-temporal characteristics of the velocity field, comparing two configurations under the same flow regimes and equipment.
MAGNETOHYDRODYNAMICS
(2021)
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)
