European Journal of Mechanics B-fluids最新文献_第2页

Dispersion - erosion coupling in landslide

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2025-01-10 DOI: 10.1016/j.euromechflu.2024.12.008

Bekha Ratna Dangol , Jeevan Kafle , Shiva P. Pudasaini

{"title":"Dispersion - erosion coupling in landslide","authors":"Bekha Ratna Dangol , Jeevan Kafle , Shiva P. Pudasaini","doi":"10.1016/j.euromechflu.2024.12.008","DOIUrl":"10.1016/j.euromechflu.2024.12.008","url":null,"abstract":"<div><div>Non-hydrostatic dispersive models can better describe the landslide motion. Following a dispersive wave equation and a mechanical erosion model for mass flows, here, we develop a novel dynamically coupled dispersion–erosion wave model that combines these two very essential complex processes. The newly developed model for landslide recovers the classical dispersive water waves and dispersive wave equation for landslide as special cases. We present several exact analytical solutions for the coupled dispersion–erosion model. These solutions are constructed for the time and spatial evolution of the flow depth. Solutions reveal that the dispersion and erosion are strongly coupled as they synchronously control the landslide dynamics. The results show that the wave dispersive wave amplifies with the increasing particle concentration, decreasing earth pressure, higher gravitational acceleration, increased slope angle and increased basal friction. The important novel understanding is that the intensity of the dispersive wave increases when erosion and dispersion are coupled. The results indicate the essence of proper selection of the initial and boundary conditions while solving applied and engineering problems associated with the dispersive-erosive mass transport. This provides the foundation for our understanding of the complex dispersion and erosion processes and their interplay.</div></div>","PeriodicalId":11985,"journal":{"name":"European Journal of Mechanics B-fluids","volume":"111 ","pages":"Pages 201-214"},"PeriodicalIF":2.5,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143093480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Boulder transport under mixed-lubrication friction

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2025-01-08 DOI: 10.1016/j.euromechflu.2025.01.001

J. DuBerry-Mahon , J.G. Herterich

引用次数: 0

Multiple drops solidifying on a surface with a temperature gradient

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2025-01-02 DOI: 10.1016/j.euromechflu.2024.12.009

Nang X. Ho , Thuc V. Yen , Truong V. Vu

{"title":"Multiple drops solidifying on a surface with a temperature gradient","authors":"Nang X. Ho , Thuc V. Yen , Truong V. Vu","doi":"10.1016/j.euromechflu.2024.12.009","DOIUrl":"10.1016/j.euromechflu.2024.12.009","url":null,"abstract":"<div><div>In many applications, liquid drops perform their solidification on a surface of non-constant cooling temperatures. Such a surface results in various behaviors of drops during the solidification process. Revealing this solidification is the central point of the present study through numerical simulations. Three liquid drops simultaneously start to solidify on a sub-melting-point temperature surface. The surface is coldest on the right side and its temperature linearly increases with respect to the position from the right to the left, resulting in a surface temperature gradient. Thereby, the phase-change interface becomes inclined in all drops with its slope increasing with the surface temperature gradient. The rightmost drop finishes its solidification first while the leftmost drop completes last. With volume expansion, an apex located at the drop top always occurs for all solidified drops. However, unlike drops on a constant temperature surface, the apex of the drops with the surface temperature gradient has a tendency to shift more to the left, resulting in an increase in the apex shift with the surface temperature gradient.</div></div>","PeriodicalId":11985,"journal":{"name":"European Journal of Mechanics B-fluids","volume":"111 ","pages":"Pages 113-119"},"PeriodicalIF":2.5,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143093200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Special issue on experimental investigations of fluid mechanics problems in large ocean research laboratories 大型海洋研究实验室流体力学问题实验研究特刊

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2025-01-01 DOI: 10.1016/j.euromechflu.2024.08.005

Y. Li, D.M. Greaves, A.G.L. Borthwick, T.S. van den Bremer

引用次数: 0

Recent advances in the analysis of turbulent superstructures 湍流上层结构分析的最新进展

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2025-01-01 DOI: 10.1016/j.euromechflu.2024.07.014

Jörg Schumacher , Wolfgang Schröder

引用次数: 0

The horizontal far wake behind a heated or cooled body

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2024-12-30 DOI: 10.1016/j.euromechflu.2024.12.007

Wilhelm Schneider, Lukáš Bábor

{"title":"The horizontal far wake behind a heated or cooled body","authors":"Wilhelm Schneider, Lukáš Bábor","doi":"10.1016/j.euromechflu.2024.12.007","DOIUrl":"10.1016/j.euromechflu.2024.12.007","url":null,"abstract":"<div><div>Buoyancy affects the horizontal wake far downstream of a heated or cooled body in an indirect manner via the hydrostatic pressure perturbation. Plane flow at large Reynolds and Péclet numbers is considered in this paper. The buoyancy effects are characterized by a Richardson number. Both laminar and turbulent flows are investigated to provide asymptotic solutions that are suitable as outflow boundary conditions in computational fluid dynamics.</div><div>Similarity transformations, which are universal, lead to sets of ordinary differential equations. The interaction between the wake and the outer potential flow is taken into account by applying Bernoulli’s equation as a boundary condition. As the thermal energy equation and the boundary conditions for the temperature perturbation are homogeneous, the magnitude of the temperature perturbation is determined by the over-all thermal energy balance.</div><div>The results of the analysis are in remarkable contrast to the classical non-buoyant wake solutions. Driven by the hydrostatic pressure disturbance, the flow does not decay in streamwise direction. The flow is governed by the total heat flow at the body, whereas the effect of the drag force is negligible.</div><div>The set of ordinary differential equations is solved numerically. For laminar flow, two kinds of solutions are found for Richardson numbers below 0.734. One kind of solutions describes a flow field containing a reversed-flow region. For turbulent flow a turbulence model based on the turbulent kinetic energy balance is applied. In addition, the limit of weak buoyancy effects is considered, leading to power laws in terms of the Richardson number.</div></div>","PeriodicalId":11985,"journal":{"name":"European Journal of Mechanics B-fluids","volume":"111 ","pages":"Pages 250-265"},"PeriodicalIF":2.5,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143093475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An experimental study on the transition of electrohydrodynamic spraying process and regime

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2024-12-27 DOI: 10.1016/j.euromechflu.2024.12.006

Yin Guan, Yanxiu Sha, Mengduo Wang, Bin He, Jingze Zheng, Zouwei Hu, Yihang Lei

{"title":"An experimental study on the transition of electrohydrodynamic spraying process and regime","authors":"Yin Guan, Yanxiu Sha, Mengduo Wang, Bin He, Jingze Zheng, Zouwei Hu, Yihang Lei","doi":"10.1016/j.euromechflu.2024.12.006","DOIUrl":"10.1016/j.euromechflu.2024.12.006","url":null,"abstract":"<div><div>Electrohydrodynamic (EHD) spraying based manufacturing techniques are remarkably useful for the fabrication of micro/nanoscopic multi-functional devices but also quite complicated owing to their highly changeable spraying behavior and regime. For the propose of gaining more knowledge about different EHD spraying process and regime, this paper carries out an experimental study on EHD spraying of ethanol under a wide range of three key operating parameters: applied voltage (<span><math><mi>Φ</mi></math></span> = 1500– 4000 V), flow rate (<span><math><mi>Q</mi></math></span> = 0.05, 0.1, 0.2, 0.3 mL/min), and nozzle height (<span><math><mi>H</mi></math></span> = 5, 10, 20, 30 mm), while nozzle height was a variable that was barely investigated in previous EHD spraying studies. Six distinct spraying regimes, namely Dripping, Spindle, Atomization, Spindle + Atomization, Whipping, and Oscillation are discovered, whose dependences on these three parameters are demonstrated and explained. Besides, as a significant part of the EHD spraying process, the variations of the spraying period and morphology with these three parameters are also discussed. Moreover, the variations of the spraying regime, spraying frequency, and nondimensionalized Taylor cone length with the electric Bond number and dimensionless flow rate are analyzed, which signifies the close correlation between these dimensionless variables and liquid spraying behaviors. The findings in this work can be used for promoting the understanding of EHD spraying process and achieving more accurate regulation of EHD spraying based manufacturing techniques.</div></div>","PeriodicalId":11985,"journal":{"name":"European Journal of Mechanics B-fluids","volume":"111 ","pages":"Pages 87-99"},"PeriodicalIF":2.5,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Euler fluid mechanics solutions to Dirac quantum mechanics equation using multipolar oscillations in spherical geometry

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2024-12-27 DOI: 10.1016/j.euromechflu.2024.12.004

Álvaro Viúdez

引用次数: 0

Deformable droplet under Poiseuille flow: Role of flow direction, channel inclination and off-centre dynamics

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2024-12-21 DOI: 10.1016/j.euromechflu.2024.12.005

Shubham Lanjewar, Sundari Ramji

{"title":"Deformable droplet under Poiseuille flow: Role of flow direction, channel inclination and off-centre dynamics","authors":"Shubham Lanjewar, Sundari Ramji","doi":"10.1016/j.euromechflu.2024.12.005","DOIUrl":"10.1016/j.euromechflu.2024.12.005","url":null,"abstract":"<div><div>The dynamics of a confined, deformable droplet with an imposed external flow (upward, quiescent and downward) is numerically investigated using an in-house solver based on the Level Set method. This is the first comprehensive investigation unravelling (i) the oscillatory dynamics of an off-centered droplet under an external flow, (ii) the hydrodynamics of a droplet subjected to a downward flow, and (iii) the effect of channel orientation. Both co-current and counter-current droplet motions are explored. While a freely falling initially off-centered droplet demonstrates an oscillatory trajectory with significant shape deformation, we show that an imposed downward flow dampens the oscillations and minimizes deformation resulting in a greater terminal speed of the droplet. Conversely, an upward, counter-current flow causes greater droplet deformation with increased oscillations. Moreover, reducing the channel inclination leads to asymmetric droplet shapes with uneven film thickness on either side of the channel and a higher residence time. The other key findings include (i) transition from convex to concave droplet tail in both upward and downward flows, dictated by the strength of external flow and <span><math><mi>Bo</mi></math></span>. (ii) Formation of a streamlined droplet accompanied by an increase in the film thickness on increasing viscosity ratio in both co-current and counter-current droplet flows and (iii) the generation of novel flow maps in the density ratio - pressure drop parameter space delineating three distinct regions: downward sinking, upward rising, and stationary droplet, depending on the relative strength of buoyancy and external flow.</div></div>","PeriodicalId":11985,"journal":{"name":"European Journal of Mechanics B-fluids","volume":"111 ","pages":"Pages 100-112"},"PeriodicalIF":2.5,"publicationDate":"2024-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A mathematical model for viscous flow dynamics of tropical cyclones

IF 2.5 3区工程技术

European Journal of Mechanics B-fluids Pub Date : 2024-12-16 DOI: 10.1016/j.euromechflu.2024.12.003

Sanjay Kumar Pandey, Kriti Yadav

{"title":"A mathematical model for viscous flow dynamics of tropical cyclones","authors":"Sanjay Kumar Pandey, Kriti Yadav","doi":"10.1016/j.euromechflu.2024.12.003","DOIUrl":"10.1016/j.euromechflu.2024.12.003","url":null,"abstract":"<div><div>A mathematical model for tropical cyclones’ winds, taking into account various crucial considerations makes the analysis of Cecil and Majdalani (2022) more realistic. Drawing inspiration from their work which obtains the axial velocity from the stream function, we incorporate the notion of viscous flow within cyclone dynamics, a modification that brings present model more closely aligned with the real-world conditions. Our key considerations include the absence of axial velocity at the ground, zero radial velocity at the cyclone’s centre, and outside the eye-wall. In order to derive pressure, we integrate axial pressure gradient with respect to axial coordinate; and as a consequence we get an arbitrary function of radial coordinate which we eliminate by using Vatistas (1991) velocity at the ground to meet the cyclostrophic balance. Azimuthal velocity and pressure are derived for viscous flows. The formulations hold good for arbitrary Reynolds number. The analysis demonstrates a positive relationship between Reynolds number and azimuthal velocity within cyclone’s eye. This trend persists within the inner eye-wall, characterized by a gradually diminishing velocity. An inflexion point is identified midway the eye and the eye-wall, where maximum azimuthal velocities are observed. The central focus of our study revolves around the influence of eye size on various velocity components and pressure. Our findings reveal that a larger eye size correlates with the development of more intense tropical storms. However, this increase in storm intensity reaches a peak and subsequently experiences a rapid decline within the rain band region compared to smaller eye cyclones. Regardless of the eye’s size, our analysis consistently demonstrates that atmospheric pressure increases as one moves away from the eye.</div></div>","PeriodicalId":11985,"journal":{"name":"European Journal of Mechanics B-fluids","volume":"111 ","pages":"Pages 72-80"},"PeriodicalIF":2.5,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0