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Smoothed particle hydrodynamics based numerical study of hydroplaning considering permeability characteristics of runway surface

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 319-333页

作者： Yang YANG Xingyi ZHU denis JELAGIN Alvaro GUArIN Key Laboratory of road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 200092China Auto Engineering research Institute BYD Auto Industry Company LimitedShenzhen 518118China Department of Civil and Architectural Engineering KTH Royal Institute of TechnologyStockholm 10044Sweden

The presence of water films on a runway surface presents a risk to the landing of *** tire of the aircraft is separated from the runway due to a hydrodynamic force exerted through the water film,a phenomenon called *** a lot of numerical investigations into hydroplaning have been conducted,only a few have considered the impact of the runway ***,computational problems,such as excessive distortion and computing efficiency decay,may arise with such numerical models when dealing with the thin water *** paper presents a numerical model comprising of the tire,water film,and the interaction with the runway,applying a mathematical model using the smoothed particle hydrodynamics and finite element(SPH-FE)*** material properties and geometric features of the tire model were included in the model framework and water film thicknesses from 0.75 mm to 7.5 mm were used in the numerical ***,this work investigated the impacts of both surface texture and the runway *** interaction between tire rubber and the rough runway was analyzed in terms of frictional force between the two *** SPH-FE model was validated with an empirical equation proposed by the National Aeronautics and Space Administration(NASA).Then the computational efficiency of the model was compared with the traditional coupled Eulerian-Lagrangian(CEL)*** on the SPH-FE model,four types of the runway(Flat,SMA-13,AC-13,and OGFC-13)were *** simulation of the asphalt runway shows that the SMA-13,AC-13,and OGFC-13 do not present a hydroplaning risk when the runway permeability coefficient exceeds 6%.

关键词： SPH-FE approach hydroplaning numerical simulation surface texture runway surface reconstruction

recent advances in the magnetic reconnection, dipolarization, and auroral processes at giant planets from the perspective of comparative planetology

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Earth and Planetary Physics 2024年第5期8卷 659-672页

作者： ZhongHua Yao ruiLong Guo Yong Wei Bertrand Bonfond denis Grodent BinZheng Zhang William r.Dunn ZuYin Pu Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde Liège Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong University Department of Earth Sciences the University of Hong Kong Department of Physics and Astronomy University College London School of Earth and Space Sciences Peking University

Magnetic reconnection and dipolarization are crucial processes driving magnetospheric dynamics, including particle energization, mass circulation, and auroral processes, among others. recent studies have revealed that these processes at Saturn and Jupiter are fundamentally different from the ones at Earth. The reconnection and dipolarization processes are far more important than previously expected in the dayside magnetodisc of Saturn and potentially Jupiter. Dayside magnetodisc reconnection was directly identified by using Cassini measurements(Guo rL et al., 2018b) and was found to be drizzle-like and rotating in the magnetosphere of Saturn(Delamere et al., 2015b; Yao ZH et al., 2017a; Guo rL et al., 2019). Moreover, magnetic dipolarization could also exist at Saturn's dayside(Yao ZH et al., 2018), which is fundamentally different from the terrestrial situation. These new results significantly improve our understanding of giant planetary magnetospheric dynamics and provide key insights revealing the physics of planetary aurorae. Here, we briefly review these recent advances and their potential implications for future investigations.

关键词： magnetosphere magnetic reconnection magnetic depolarization

Averaged Dynamics of Fluids near the Oscillating Interface in a Hele-Shaw Cell

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Fluid Dynamics & Materials Processing 2024年第4期20卷 847-857页

作者： Anastasia Bushueva Olga Vlasova denis Polezhaev Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia

The steady flow in a Hele-Shaw cell filled with fluids with a high viscosity contrast in the presence of fluid oscillations is experimentally *** control of oscillatory dynamics of multiphase systems with interfaces is a challenging technological *** consider miscible(water and glycerol)and immiscible(water and high-viscosity silicone oil PMS-1000)fluids under subsonic oscillations perpendicular to the *** show that the interface shape depends on the amplitude and frequency of *** interface is undisturbed only in the absence of *** small amplitudes,the interface between water and glycerol widens due to *** the critical amplitude is reached,the interface becomes unstable to the fingering instability:Aqueous fingers penetrate the high-viscosity glycerol and induce intensive mixing of miscible fluids and associated decay of the *** the disappearance of the fingers,the interface takes a U-shape in the central part of the cell.A similar effect is observed for immiscible fluids:The oscillating interface tends to bend to the side of a high-viscosity ***,when the critical amplitude is reached,the fingering instability arises at the convex *** paper focuses on the causes of bending of the initially undisturbed interface between miscible or immiscible *** this purpose,we measure the steady flow velocity near the interface and in the bulk of a high-viscosity fluid using Particle Image Velocimetry(PIV).

关键词： Hele-Shaw cell oscillations steady flow miscible fluids immiscible fluids interface

residence time distribution of wood chips in a semi-industrial multiple hearth furnace using rFID tracers Author links open overlay panel

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Particuology 2024年第8期91卷 268-279页

作者： Elie Lacombe Muriel Marchand Capucine Dupont denis Maréchal Thierry Melkior Univ Grenoble Alpes CEALITENDTCHLaboratoire Réacteurs et ProcédésF-38000GrenobleFrance IHE Delft Department of Water Supply Sanitation and Environmental EngineeringDelftthe Netherlands John Cockerill SeraingBelgium

In continuous biomass torrefaction plants,the products'yields,composition and homogeneity highly depend on the residence time of particles.A characterization of particle residence time distribution(rTD)was therefore carried out in an industrial-scale multiple hearth furnace on poplar wood chips using radio frequency identification *** effects of operating conditions,namely,mass flow rate of biomass,shaft speed of the rabbling system and interdental length on the rTD were *** increase of shaft speed and mass flow rate reduces particles’mean residence *** the length between two successive teeth also increases the bed *** biomass accumulation(also called“bulldozing”)was observed during several *** phenomenon is favored by a high mass flow rate of resources,a small interdental length between the teeth and a low shaft *** measurements were compared to the axial dispersion *** all tests,the Peclet number is ranging between 20 and 62,indicating that the multiple hearth furnace cannot be modelled as an ideal plug flow reactor.

关键词： Biomass Multiple hearth furnace residence time distribution rFID

The penetration depth of atomic radicals in tubes with catalytic surface properties

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Plasma Science and Technology 2024年第7期26卷 157-164页

作者： Domen PAUL Miran MOZETIC rok ZAPLOTNIK Alenka VESEL Gregor PrIMC denis DONLAGIC Jozef Stefan Institute Jamova Cesta 39Ljubljana 1000Slovenia Jozef Stefan International Postgraduate School Jamova Cesta 39Ljubljana 1000Slovenia Faculty of Electrical Engineering and Computer Science University of MariborKoroska Cesta 46Maribor 2000Slovenia

Catalysis of molecular radicals is often performed in interesting experimental *** possible configuration is tubular *** radicals are introduced into the tubes on one side,and stable molecules are exhausted on the other *** penetration depth of radicals depends on numerous parameters,so it is not always feasible to calculate *** article presents systematic measurements of the penetration depth of oxygen atoms along tubes made from nickel,cobalt,and *** source of O atoms was a surfatron-type microwave *** initial density of O atoms depended on the gas flow and was 0.7×10^(21)m^(-3),2.4×10^(21)m^(-3),and 4.2×10^(21)m^(-3)at the flow rates of 50,300,and 600 sccm,and pressures of 10,35,and 60 Pa,*** gas temperature remained at room temperature throughout the *** dissociation fraction decreased exponentially along the length of the tubes in all *** penetration depths for well-oxidized nickel were 1.2,1.7,and 2.4 cm,*** cobalt,they were slightly lower at 1.0,1.3,and 1.6 cm,respectively,while for copper,they were 1.1,1.3,and 1.7 cm,*** results were explained by gas dynamics and heterogeneous surface *** data are useful in any attempt to estimate the loss of molecular fragments along tubes,which serve as catalysts for the association of various radicals to stable molecules.

关键词： oxygen plasma penetration depth catalysis heterogeneous surface recombination atom loss

Comparison of ErA5 turbulent fluxes at the air-sea interface with measurements from a wave-following platform

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Atmospheric and Oceanic Science Letters 2024年第3期17卷 32-36页

作者： Said Benjeddou denis Bourras Christopher Luneau Aix Marseille Universite National Center for Scientific ResearchMediterranean Institute of OceanographyMarseilleFrance Observatory of the Sciences of the Universe Pytheas Institute National Center for Scientific ResearchMarseilleFrance

Turbulent fluxes at the air-sea interface were estimated with data collected in 2011-2020 with a low-profile platform named OCArINA during eight experiments in five regions:2011,2015,and 2016 in the Iroise Sea;2012 in the tropical Atlantic;2014 in the Chilie-Peru upwelling;2017 and 2018 in the Mediterranean Sea,and 2018 and 2020 in *** observations were carried out with moderate winds(2-10 m s^(-1))and average wave heights of 1.5 *** this study,the authors used the fluxes calculated by the bulk method using OCArINA-sampled data as the *** data can validate the fluxes estimated from ErAS reanalysis *** OCArINA and ErA5 data were taken *** do this,the authors established an algorithm to extract the OCArINA data as closely as possible to the reanalysis data in time and *** measurements of the OCArINA platform can conclude on the relevance of the widely used reanalysis data.

关键词： Ocarina ECMWF ErA5 Turbulent fluxes Louis formulation

Differential Game Model of resource Extraction with Continuous and Dynamic Updating

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Journal of the Operations research Society of China 2024年第1期12卷 51-75页

作者： Ovanes Petrosian Tihomirov denis Jiang-Jing Zhou Hong-Wei Gao School of Mathematics Harbin Institute of TechnologyHarbin150001HeilongjiangChina School of Automation Qingdao UniversityQingdao266071ShandongChina Faculty of Applied Mathematics and Control Processes Saint-Petersburg State UniversitySaint PetersburgRussia National research University"High School of Economics" Saint-PetersburgRussia School of Mathematics and Statistics Qingdao UniversityQingdao266071ShandongChina

This paper is devoted to a new class of differential games with continuous and dynamic *** direct application of resource extraction in a case of dynamic and continuous updating is *** is proved that the optimal control(cooperative strategies)and feedback Nash equilibrium strategies uniformly converge to the corresponding strategies in the game model with continuous updating as the number of updating instants converges to *** results are presented for an optimal trajectory(cooperative trajectory),equilibrium trajectory and corresponding payoffs.

关键词： Differential games Dynamic updating Continuous updating Optimal control Feedback Nash equilibrium

Long-term Speckle Interferometric Monitoring of Binary Systems:2007–2023Positional Measurements and Orbits of Seven Objects

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research in Astronomy and Astrophysics 2024年第9期24卷 147-155页

作者： Arina Mitrofanova Vladimir Dyachenko Anatoly Beskakotov Yuri Balega Alexander Maksimov denis rastegaev Special Astrophysical Observatory 369167 Nizhnij ArkhyzRussia

The results of seventeen years of speckle interferometric monitoring of seven objects(Chara 122Aa,GJ 3010,HIP1987,GJ 3076,HIP 11253,HIP 11352,and HIP 14929)are *** data were obtained at the 6 m Big Telescope Alt-azimuthal Special Astrophysical Observatory of the russian Academy of Science(BTA SAO rAS)from 2007 to the *** of previously published and new measurements made it possible to construct completely new orbits for Chara 122Aa,HIP 11253,and HIP *** orbit of GJ 3076 cannot be constructed accurately due to the large influence of the weights assigned to the *** resulting orbital solutions are classified based on a grading scheme suggested by ***,*** and ***;most orbits are“definitive”(Grade 1).The mass sums and masses of components calculated by two independent methods using Hipparcos and Gaia Dr2 and Dr3 parallaxes were compared for the objects under study.

关键词： techniques:high angular resolution (stars:)binaries:visual stars:fundamental parameters stars:low-mass stars:solar-type

Kriging-boosted Cr modeling for prompt infill drilling optimization

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Petroleum 2024年第1期10卷 39-48页

作者： Elizaveta S.Gladchenko Anna E.Gubanova denis M.Orlov Dmitry A.Koroteev Skolkovo Institute of Science and Technology Russian Federation Digital Petroleum LLC Russian Federation

The capacitance-resistance model(CrM)has been a useful physics-based tool for obtaining production forecasts for ***,the model's limitations make it difficult to work with real field cases,where a lot of various events *** events often include new well commissioning(NWC).We introduce a workflow that combines CrM concepts and kriging into a single tool to handle these types of events during history ***,it can be used for selecting a new well placement during infill *** make the workflow even more versatile,an improved version of CrM was *** takes into account wells shut-ins and performed workovers by additional adjustment of the model *** preliminary re-weighing and interpolating these coefficients using kriging,the coefficients for potential wells can be *** approach was validated using both synthetic and real datasets,from which the cases of putting new wells into operation were *** workflow allows a fast assessment of future well performance with a minimal set of reservoir *** way,a lot of well placement scenarios can be considered,and the best ones could be chosen for more detailed studies.

关键词： Capacitance-resistance model(CrM) Field development optimization Infill drilling Interwell connectivity Kriging New well commissioning(NWC)