J. Eggers, M. A. Fontelos
We consider an axisymmetric, freely suspended fluid drop with surface tension, whose viscosity is so large that both inertia and forcing by an external fluid can be ignored. We show that whatever be the initial condition, pinchoff can never occur.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
继续探索
It is generally accepted that the Worthington jet occurs when a droplet impacts onto a liquid pool. However, in this experimental study of the impact of viscous droplets onto a less-viscous liquid pool, we identify another jet besides the Worthington jet, forming a two-jet phenomenon. The two jets, a surface-climbing jet and the Worthington jet, may appear successively during one impact event. By carefully tuning the impact condition, we find that the two-jet phenomenon is jointly controlled by the droplet-pool viscosity ratio, the droplet Weber number, and the droplet-pool miscibility. The me…
Drop-drop coalescence: a simple crossover function between inertial and viscous dynamics
本文通过高速成像实验研究液滴聚并中粘性与惯性区域间的过渡，提出无量纲交叉函数标度方法，成功将不同粘度和时间下的实验数据统一到一条主曲线上，补充并扩展了现有理论模型。
The physico-chemistry of surfactants (amphiphilic surface active agents) is often used to control the dynamics of viscous drops and bubbles. Surfactant sorption kinetics has been shown to play a critical role in the deformation of drops in extensional and shear flows, yet to the best of our knowledge these kinetics effects on a viscous drop in an electric fieldhave not been accounted for. In this paper we numerically investigate the effects of sorption kinetics on a surfactant-covered viscous drop in an electric field. Over a range of electric conductivity and permittivity ratios between the i…
Liquid drops start spreading directly after coming into contact with a solid sub- strate. Although this phenomenon involves a three-phase contact line, the spread- ing motion can be very fast. We experimentally study the initial spreading dy- namics, characterized by the radius of the wetted area, for viscous drops. Using high-speed imaging with synchronized bottom and side views gives access to 6 decades of time resolution. We show that short time spreading does not exhibit a pure power-law growth. Instead, we find a spreading velocity that decreases logarithmically in time, with a dynamics i…
We present convincing evidence of a direct connection between the pressure drop, viscous dissipation, and the turbulent energy spectrum. We use this finding to explain Nikuradse's experimental results of pressure drop for turbulent flows in rough pipes, in terms of a modified Kolmogorov length scale that varies with the surface roughness. Furthermore, we use Laufer's measurements of turbulent energy spectra in pipe flow to calculate -- to a good approximation -- the turbulent component of the pressure drop directly from an averaged turbulent energy spectrum. We also show that the incompressibi…
We simulate the impact of a viscous liquid drop onto a smooth dry solid surface. As in experiments, when ambient air effects are negligible, impact flattens the falling drop without producing a splash. The no-slip boundary condition at the wall produces a boundary layer inside the liquid. Later, the flattening surface of the drop traces out the boundary layer. As a result, the eventual shape of the drop is a "pancake" of uniform thickness except at the rim, where surface tension effects are significant. The thickness of the pancake is simply the height where the drop surface first collides wit…
The axisymmetric deformation and motion of interacting droplets in an imposed temperature gradient is considered using boundary-integral techniques for slow viscous motion. Results showing temporal drop motion, deformations and separation are presented for equal-viscosity fluids. The focus is on cases when the drops are of equal radii or when the smaller drop trails behind the larger drop. For equal-size drops, our analysis shows that the motion of a leading drop is retarded while the motion of the trailing one is enchanced compared to the undeformable case. The distance between the centers of…
Thermocapillary migration of an odd viscous droplet on a uniformly heated surface: A lattice Boltzmann study
本研究通过格子玻尔兹曼方法揭示奇粘性使液滴在均匀加热表面上自发迁移，方向取决于奇粘性符号，速度受接触角和粘度比影响，且可逆重力爬升。
After decades of experimental, theoretical, and numerical research in fluid dynamics, many aspects of turbulence remain poorly understood. The main reason for this is often attributed to the multiscale nature of turbulent flows, which poses a formidable challenge. There are, however, properties of these flows whose roles and inter-connections have never been clarified fully. In this article, we present a new connection between the pressure drop, viscous dissipation, and the turbulent energy spectrum, which, to the best of our knowledge, has never been established prior to our work. We use this…
Capillary currents and viscous droplet spreading
研究粘性液滴在粗糙基底上的扩散行为，提出新的毛细流模型，解释了不同尺度液滴的扩散规律。
Steady translation of a chemically active viscous drop along a rigid wall
本研究通过理论分析化学活性粘性液滴沿刚性壁面的平动，发现低粘度液滴更靠近壁面且游动更快，并证明其速度对迁移率比依赖较弱，为扩散泳粒子模型的有效性提供了定量依据。
Thin, viscous liquid films subjected to impact events can deform. Here we investigate free surface oil film deformations that arise due to the air pressure buildup under the impacting and rebouncing water drops. Using Digital Holographic Microscopy, we measure the 3D surface topography of the deformed film immediately after the drop rebound, with a resolution down to 20 nm. We first discuss how the film is initially deformed during impact, as a function of film thickness, film viscosity, and drop impact speed. Subsequently, we describe the slow relaxation process of the deformed film after the…
We study drop impacts on immiscible viscous liquid pool and investigate the formation of droplet surface craters using experimental and theoretical analysis. We attribute the formation of air craters to the rapid deceleration of the droplet due to viscous drag force. The droplet response to the external impulsive decelerating force induces oscillatory modes on the surface exposed to the air forming capillary waves that superimpose to form air craters of various shapes and sizes. We introduce a non-dimensional parameter ($Γ$), that is, the ratio of drag force to the capillary force acting on th…
After impact onto a smooth dry surface, a drop of viscous liquid initially spreads in the form of a thick lamella. If the drop splashes, it first emits a thin fluid sheet that can ultimately break up into droplets causing the splash. Ambient gas is crucial for creating this thin sheet. The time for sheet ejection, $t_{ejt}$, depends on impact velocity, liquid viscosity, gas pressure and molecular weight. A central air bubble is trapped below the drop at pressures even below that necessary for this sheet formation. In addition, air bubbles are entrained underneath the spreading lamella when the…
The motion of a viscous drop is investigated when the interface is fully covered with a stagnant layer of surfactant in an arbitrary unsteady Stokes flow for the low surface Péclet number limit. The effect of the interfacial slip coefficient on the behavior of the flow field is also considered. The hydrodynamic problem is solved by the solenoidal decomposition method and the drag force is computed in terms of Faxen's laws using a perturbation ansatz in powers of the surface Péclet number. The analytical expressions for the migration velocity of the drop are also obtained in powers of the surfa…
The behaviour of a viscous drop squeezed between two horizontal planes is treated by both theory and experiment. When the squeezing force F is constant and surface tension is neglected, the theory predicts ultimate growth of the radius a~ t^{1/8}, in excellent agreement with our experiment. Surface tension at the drop boundary is included in the analysis, although negligibly small in the squeezing experiments. The circular evolution is found to be stable under small perturbations. If the force is reversed (F < 0), so that the plates are pulled or levered apart, the boundary of the drop is subj…
The experimental observation of D. Duft, T. Achtzehn, R. Muller, B. A. Huber, and T. Leisner, Nature 421, 128 (2003) on the sequential progression of the instability of a charged liquid drop points at the formation of a jet followed by the emission of progeny droplets as a crucial pathway of the Rayleigh fission process. In spite of considerable theoretical progress, a quantitative understanding of this breakup pathway through mathematical models has largely remained inconclusive. This limitation has mainly been due to the fact that the generally applied electrostatic boundary condition of the…
The aim of this study is to derive accurate models for quantities characterizing the dynamics of droplets of non-vanishing viscosity in capillaries. In particular, we propose models for the uniform-film thickness separating the droplet from the tube walls, for the droplet front and rear curvatures and pressure jumps, and for the droplet velocity in a range of capillary numbers, $Ca$, from $10^{-4}$ to $1$ and inner-to-outer viscosity ratios, $λ$, from $0$, i.e. a bubble, to high viscosity droplets. Theoretical asymptotic results obtained in the limit of small capillary number are combined with…
We study the phenomenon of the "walking droplet", by means of numerical fluid dynamics simulations using the Smoothed Particle Hydrodynamics numerical method. This phenomenon occurs when a millimetric drop is released on the surface of an oil of the same composition, contained in a tank and subjected to vertical oscillations of frequency and amplitude very close to the Faraday instability threshold. At appropriate values of the parameters of the system under study, the oil droplet jumps permanently on the surface of the vibrating liquid forming a localized wave-particle system, reminding the b…
Theory for the coalescence of viscous lenses
本文基于薄片方程，通过数值模拟和匹配渐近分析，研究了二维黏性液体透镜的聚并动力学，发现其前导阶自相似解受边界条件修正，并可能伴随液滴整体平移。
Retraction of levitating drops
本研究针对零重力下悬浮牛顿液滴的回缩开展理论与数值分析，揭示三种回缩机制的物理规律，提出用回缩数这一无量纲参数关联回缩时间与机制的二维图，完善了相关动力学与标度律认识。
Using an electrical method and high-speed imaging we probe drop coalescence down to 10 ns after the drops touch. By varying the liquid viscosity over two decades, we conclude that at sufficiently low approach velocity where deformation is not present, the drops coalesce with an unexpectedly late crossover time between a regime dominated by viscous and one dominated by inertial effects. We argue that the late crossover, not accounted for in the theory, can be explained by an appropriate choice of length-scales present in the flow geometry.
The interface formation model is applied to describe the initial stages of the coalescence of two liquid drops in the presence of a viscous ambient fluid whose dynamics is fully accounted for. Our focus is on understanding (a) how this model's predictions differ from those of the conventionally used one, (b) what influence the ambient fluid has on the evolution of the shape of the coalescing drops and (c) the coupling of the intrinsic dynamics of coalescence and that of the ambient fluid. The key feature of the interface formation model in its application to the coalescence phenomenon is that …
Macro-textured superhydrophobic surfaces can reduce droplet-substrate contact times of impacting water droplets, however, surface designs with similar performance for significantly more viscous liquids are missing, despite their importance in nature and technology such as for chemical shielding, food staining repellency, and supercooled (viscous) water droplet removal in anti-icing applications. Here, we introduce a deterministic, controllable and up-scalable method to fabricate superhydrophobic surfaces with a 3D-printed architecture, combining arrays of alternating surface protrusions and in…
We analyse small-amplitude oscillations of a weakly viscous electrically conducting liquid drop in a strong uniform DC magnetic field. An asymptotic solution is obtained showing that the magnetic field does not affect the shape eigenmodes, which remain the spherical harmonics as in the non-magnetic case. Strong magnetic field, however, constrains the liquid flow associated with the oscillations and, thus, reduces the oscillation frequencies by increasing effective inertia of the liquid. In such a field, liquid oscillates in a two-dimensional (2D) way as solid columns aligned with the field. Tw…
A spectral boundary integral method for simulating electrohydrodynamic flows in viscous drops
提出一种谱边界积分方法，利用球谐展开和综合电荷输运模型模拟均匀电场中液滴的电流体动力学，通过加权球谐展开解决低粘度液滴的数值振铃问题，并在Taylor和Quincke电旋转区域验证了其有效性。
When a liquid drop falls on a solid substrate, the air layer in between them delays the occurrence of liquid--solid contact. For impacts on smooth substrates, the air film can even prevent wetting, allowing the drop to bounce off with dynamics identical to that observed for impacts on superamphiphobic materials. In this article, we investigate similar bouncing phenomena, occurring on viscous liquid films, that mimic atomically smooth substrates, with the goal to probe their effective repellency. We elucidate the mechanisms associated to the bouncing to non-bouncing (floating) transition using …
From the Navier-Stokes-Korteweg (NSK) equations, the exact relations between the fundamental surface physical quantities for two-phase viscous flow with diffuse interface are derived, including density gradient, shear stress, vorticity, pressure, enstrophy flux and surface curvature. These theoretical results provide a solid foundation of the boundary/interfacial vorticity dynamics and a new tool for analysis of complex interfacial phenomena in two-phase viscous flows. To demonstrate the application of the developed results, simulation of a droplet impacting and spreading on a solid wall is co…
A partially-wetting sessile drop is driven by a sinusoidal pressure field that produces capillary waves on the liquid/gas interface. The analysis presented in Part 1 of this series (Bostwick & Steen 2014) is extended by computing response diagrams and phase shifts for the viscous droplet, whose three phase contact-line moves with contact-angle that is a smooth function of the contact line speed. Viscous dissipation is incorporated through the viscous potential flow approximation and the critical Ohnesorge number bounding regions beyond which a given mode becomes over-damped is computed. Davis …
Self-organized dynamics of a viscous drop with interfacial nematic activity
本研究通过流体动力学模拟，揭示了界面向列活性驱动粘性液滴产生从缺陷编织到活性湍流的自组织行为，并解释了形态变化的机制。
The Navier-Stokes equations and boundary conditions for viscous fluids of capillary size are formulated in curvilinear coordinates associated with a geometry of the fluid-gas interface. As a result, the fluid dynamics of drops and menisci can be described taking into account an influence of gravitational forces and flows on the surface shape. This gives a convenient basis for respective numerical studies. Estimations of the effects are presented for the case of an evaporating sessile drop.
The coalescence of two liquid drops surrounded by a viscous gas is considered in the framework of the conventional model. The problem is solved numerically with particular attention to resolving the very initial stage of the process which only recently has become accessible both experimentally and computationally. A systematic study of the parameter space of practical interest allows the influence of the governing parameters in the system to be identified and the role of viscous gas to be determined. In particular, it is shown that the viscosity of the gas suppresses the formation of toroidal …
A classic result due to G.I.Taylor is that a drop placed in a uniform electric field becomes a prolate or oblate spheroid, which is axisymmetrically aligned with the applied field. We report an instability and symmetry-breaking transition to obliquely oriented, steady and unsteady shapes in strong fields. Our experiments reveal novel droplet behaviors such as tumbling, shape oscillations, and chaotic dynamics even under creeping flow conditions. A theoretical model, which includes anisotropy in the polarization relaxation due to drop asphericity and charge convection due to drop fluidity, eluc…
Elasto-viscous regime in coalescence of viscoelastic droplets
本研究通过实验和模拟发现，粘弹性液滴聚并中弹性导致颈部生长幂律指数随时间转变，进入亚牛顿区，并利用指数Phan-Thien-Tanner模型准确再现了实验现象。
We study the instability development during a viscous liquid drop impacting a smooth substrate, using high speed photography. The onset time of the instability highly depends on the surrounding air pressure and the liquid viscosity: it decreases with air pressure with the power of minus two, and increases linearly with the liquid viscosity. From the real-time dynamics measurements, we construct a model which compares the destabilizing stress from air with the stabilizing stress from liquid viscosity. Under this model, our experimental results indicate that at the instability onset time, the tw…
We investigate both experimentally and numerically the impact of liquid drops on deep pools of aqueous glycerol solutions with variable pool viscosity and air pressure. With this approach we are able to address drop impacts on substrates that continuously transition from low-viscosity liquids to almost solids. We show that the generic corolla spreading out from the impact point consists of two distinct sheets, namely an ejecta sheet fed by the drop liquid and a second sheet fed by the substrate liquid, which evolve on separated timescales. These two sheets contribute to a varying extent to the…
The shear induced collective diffusivity in an emulsion of viscous drops, specifically as a function of viscosity ratio, was numerically computed. An initially randomly packed layer of viscous drops spreading due to drop-drop interactions in an imposed shear has been simulated. The shear induced collective diffusivity coefficient was computed using a self-similar solution of the drop concentration profile. We also obtained the collective diffusivity computing the dynamic structure factor from the simulated drop positions--an analysis typically applied only to homogeneous systems. The two quant…
Electro-coalescence is the application of an electric field onto coalescing fluid bodies. The following fluid dynamics videos show a droplet coalescing into a fluid bath while embedded into a viscous medium and subject to a very high electric field. The concentration of electric stresses at the apex of the droplet cause it to break apart. The droplet is glycerol and the viscous medium is silicone oil.
Nonlinear Three-Dimensional Electrohydrodynamic Interactions of Viscous Dielectric Drops
本文建立含瞬态电荷弛豫与对流的三维半解析小变形模型，研究高黏度、远间距漏电介质液滴对在直流电场中的非线性电流体动力学相互作用及 Quincke 旋转。
We present systematic wetting experiments and numerical simulations of gravity driven liquid drops sliding on a plane substrate decorated with a linear chemical step. Surprisingly, the optimal direction to observe crossing is not the one perpendicular to the step, but a finite angle that depends on the material parameters. We computed the landscapes of the force acting on the drop by means of a contact line mobility model showing that contact angle hysteresis dominates the dynamics at the step and determines whether the drop passes onto the lower substrate. This analysis is very well supported…
The evolution of suspension drops sedimenting under gravity in a viscous fluid close to a vertical wall was studied experimentally and numerically with the use of the point-force model, in the Stokes flow regime. The fluid inside and outside the drop was identical. The initial distribution of the suspended solid heavy particles was uniform inside a spherical volume. In the experiments and in the simulations, the suspension drops evolved qualitatively in the same way as in an unbounded fluid. However, it was observed, both experimentally and numerically that, on the average, the destabilization…
Small steady-state deformational oscillations of a drop of a viscous magnetic liquid in a non-stationary uniform magnetic field are theoretically investigated for low Reynolds numbers. The drop is suspended in another viscous magnetic liquid immiscible with the former. The non-stationary magnetic field causes flow inside and outside the drop. The inertia is taken into account by regarding the flow as essentially unsteady. The variation of the magnetic field is so slow that the approximation of quasi-stationary magnetic field may be used.
We study the deformation and breakup of an axisymmetric electrolyte drop which is freely suspended in an infinite dielectric medium and subjected to an imposed electric field. The electric potential in the drop phase is assumed small, so that its governing equation is approximated by a linearized Poisson-Boltzmann or modified Helmholtz equation (the Debye-Hückel regime). An accurate and efficient boundary integral method is developed to solve the low-Reynolds-number flow problem for the time-dependent drop deformation, in the case of arbitrary Debye layer thickness. Extensive numerical results…
We characterize the flow of a viscous suspension in an inclined channel where the flow is maintained in a steady state under the competing influences of gravity and an applied pressure drop. The basic model relies on a diffusive-flux formalism. Such models are common in the literature, yet many of them possess an unphysical singularity at the channel centreline where the shear rate vanishes. We therefore present a regularization of the basic diffusive-flux model that removes this singularity. This introduces an explicit (physical) dependence on the particle size into the model equations. This …
We experimentally investigate the effect of freezing on the spreading of a water drop. Whenever a water drop impacts a cold surface, whose temperature is lower than 0°C, a thin layer of ice grows during the spreading. This freezing has a notable effect on the impact: at given Reynolds and Weber numbers, we show that lowering the surface temperature reduces the drop maximal extent. Using an analogy between this ice layer and the viscous boundary layer, which also grows during the spreading, we are able to model the effect of freezing as an effective viscosity. The scaling laws designed for visc…
How interfacial tension enhances drag in turbulent Taylor-Couette flow with neutrally buoyant and equally viscous droplets
本文通过直接数值模拟研究Taylor-Couette湍流中中性浮力等黏液滴的阻力增强机制，揭示界面张力对液滴前端的作用阻碍连续相并促进低速条带形成，从而增加系统阻力。
Wet-on-wet printing is frequently used in inkjet printing for graphical and industrial applications, where substrates can be coated with a thin liquid film prior to ink drop deposition. Two drops placed close together are expected to interact via deformations of the thin viscous film, but the nature of these capillary interactions is unknown. Here we show that the interaction can be attractive or repulsive depending on the distance separating the two drops. The distance at which the interaction changes from attraction to repulsion is found to depend on the thickness of the film, and increases …
The breakup of a jet of a viscous fluid with viscosity $μ_{1}$ immersed into another viscous fluid with viscosity $μ_{2}$ is considered in the limit when the viscosity ratio $λ=μ_{1}/μ_{2}$ is close to zero. We show that, in this limit, a transition from ordinary continuous selfsimilarity to discrete selfsimilarity takes place as $λ$decreases. The result being that instead of a single point breakup, the rupture of the inner jet occurs through the appearance of an infinite sequence of filaments of decreasing size that will eventually produce infinite sequences of bubbles of the inner fluid insi…
We study the collapse of an axisymmetric liquid filament both analytically and by means of a numerical model. The liquid filament, also known as ligament, may either collapse stably into a single droplet or break up into multiple droplets. The dynamics of the filament are governed by the viscosity and the aspect ratio, and the initial perturbations of its surface. We find that the instability of long viscous filaments can be completely explained by the Rayleigh-Plateau instability, whereas a low viscous filament can also break up due to end pinching. We analytically derive the transition betwe…
Instability of microbial droplets growing on viscous substrates
研究了在粘性基质上生长的微生物液滴的稳定性问题，通过建立模型分析生长引起的应力、营养消耗导致的密度变化以及由此产生的流体流动，发现生长力稳定轴对称解而浮力力使其不稳定。
A viscous drop in a planar linear flow -- the role of deformation on streamline topology
本文通过解析与数值方法证明，在平面线性流中，液滴变形（非零毛细数）会破坏球形液滴原有的封闭流线拓扑，使其部分转化为开放螺旋流线，部分缠绕于嵌套不变环面，纠正了先前关于封闭流线持续存在的结论。
Water Drop on Thin Viscous Oil Layers: From Stick-Slip Spreading to Dewetting
本研究通过实验探究水滴在硅油涂层表面的铺展行为，发现初始阶段低撞击能量下液滴边缘呈粘滑动力学特征，长期则由油的去润湿主导最终铺展至油层下方，且二次铺展延迟与韦伯数无关，为水油相互作用研究提供新见解。
Weakly conducting dielectric liquid drops suspended in another dielectric liquid and subject to an applied uniform electric field exhibit a wide range of dynamical behaviors contingent on field strength and material properties. These phenomena are best described by the Melcher-Taylor leaky dielectric model, which hypothesizes charge accumulation on the drop-fluid interface and prescribes a balance between charge relaxation, the jump in Ohmic currents from the bulk and charge convection by the interfacial fluid flow. Most previous numerical simulations based on this model have either neglected …
We investigate the dynamics of drop impacts on dry solid surfaces. By synchronising high-speed photography with fast force sensing, we simultaneously measure the temporal evolution of the shape and impact force of impacting drops over a wide range of Reynolds numbers (Re). At high Re, when inertia dominates the impact processes, we show that the early-time evolution of impact force follows a square-root scaling, quantitatively agreeing with a recent self-similar theory. This observation provides direct experimental evidence on the existence of upward propagating self-similar pressure fields du…
A small drop of a heavier fluid may float on the surface of a lighter fluid supported by surface tension forces. In equilibrium, the drop assumes a radially symmetric shape with a circular triple-phase contact line. We show theoretically and experimentally that such a floating liquid drop with a sufficiently small volume has two distinct stable equilibrium shapes: one with a larger and one with a smaller radius of the triple-phase contact line. Next, we experimentally study the floatability of a less viscous water drop on the surface of a more viscous and less dense oil, subjected to a low fre…
The impact of a liquid drop on a solid surface involves many intertwined physical effects, and is influenced by drop velocity, surface tension, ambient pressure and liquid viscosity, among others. Experiments by Kolinski et al. (2014b) show that the liquid-air interface begins to deviate away from the solid surface even before contact. They found that the lift-off of the interface starts at a critical time that scales with the square root of the kinematic viscosity of the liquid. To understand this, we study the approach of a liquid drop towards a solid surface in the presence of an intervenin…
Dripping-onto-droplet capillary breakup
研究滴落至液滴的毛细破裂现象，结合实验、数值模拟和理论分析，揭示不同流态下的破裂机制及影响因素。
Translation of a spherical viscous drop driven by localized forcing in Stokes flow
本研究利用洛伦兹互易定理推导了斯托克斯流中局域力驱动的球形粘性液滴平移速度积分表达式，区分了内外力的不同响应，为构建可控远场的类squirmer液滴解奠定基础。
Breakup of viscous liquid bridges on solid surfaces
本文实验研究固体表面粘性液桥断裂，结合润湿性、分子热激活跳跃与体相粘性耗散建立最小宽度标度律，并解释几何约束及卫星液滴形貌差异。
We investigate freely expanding liquid sheets made of either simple Newtonian fluids or solutions of high molecular water-soluble polymer chains. A sheet is produced by the impact of a drop on a quartz plate covered with a thin layer of liquid nitrogen that suppresses shear viscous dissipation thanks to an inverse Leidenfrost effect. The sheet expands radially until reaching a maximum diameter and subsequently recedes. Experiments indicate the presence of two expansion regimes: the capillary regime, where the maximum expansion is controlled by surface tension forces and does not depend on the …
扫码添加微信好友，提出您的宝贵建议 👇
💡 备注请填写：网站反馈
发表机构由 AI 从论文文本抽取，如发现错误，欢迎反馈修正建议。