International Journal of Multiphase Flow最新文献

{"title":"Molecular dynamics investigation of nanobubble collapse near a solid-liquid interface under realistic conditions","authors":"Qingmiao Ding,&nbsp;Zipeng Wang,&nbsp;Jian Xu,&nbsp;Yanyu Cui","doi":"10.1016/j.ijmultiphaseflow.2026.105899","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105899","url":null,"abstract":"<div><div>The collapse behavior of nanobubble in the vicinity of solid-liquid interface under impact loading critically influences material erosion, cavitation damage, and surface degradation in fluid-structure systems. This study employs the Reactive Molecular Dynamics (RMD) method to investigate the dynamic processes of nanobubble collapse near solid-liquid interface at realistic impact velocities. The simulation procedure involved initial Canonical ensemble (The NVT ensemble) equilibration of water molecules and iron atoms, followed by microcanonical ensemble (The NVE ensemble) impact loading via piston driving with an initial velocity of 5 km/s in the <em>z</em>-direction. We tracked the propagation of shock waves, the evolution of atomic velocity fields, and the spatiotemporal evolution of nanobubble radius, revealing complex deformation and collapse characteristics of nanobubble with different initial radius. Results show that nanobubble collapse morphology, energy localization effects, and momentum transfer to iron substrates are highly sensitive to nanobubble size. Notably, larger nanobubble induce local localized compressive-stress peaks that significantly alter substrate surface roughness and microstructural features, shedding light on potential mechanisms of surface erosion and fatigue initiation. This study elucidated the cavitation damage mechanism at the atomic scale, verified the reactive force field (ReaxFF) method's analytical capability in coupling chemical-mechanical responses under extreme conditions, and provided a theoretical basis for multi-scale modeling of cavitation erosion phenomena in engineering materials.</div></div>","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"203 ","pages":"Article 105899"},"PeriodicalIF":3.9,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148935323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AC electrohydrodynamic control and predictive scaling of droplet length in flow-focusing microchannels","authors":"Weiwei Xu,&nbsp;Xinyu Wang,&nbsp;Weizhao Yu,&nbsp;Qiang Li","doi":"10.1016/j.ijmultiphaseflow.2026.105893","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105893","url":null,"abstract":"<div><div>In droplet microfluidics, active control via an AC electric field is widely adopted, offering rapid response and high control accuracy. However, existing studies still lack a comprehensive understanding of droplet dynamic behavior and reliable length prediction models under AC electric fields. To address this, a self-developed InterEHDFoam solver in OpenFOAM is used to systematically explore the regulation of droplet generation dynamics by AC electric field parameters within a flow-focusing microchannel. A predictive model that couples voltage and the flow rate ratio is also developed. The results indicate that changing the electrode position of the AC electric field enables bidirectional transitions between slug and dripping flow. Furthermore, considering how droplets in dripping flow deflect under an AC electric field, a quantitative correlation between the critical voltage and the flow rate ratio is obtained, with a relative prediction error of less than 9%. Finally, through force analysis of the droplet, prediction models for droplet length are derived for the two electrode configurations, exhibiting high predictive accuracy under low voltage conditions, with relative errors within 10%.</div></div>","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"203 ","pages":"Article 105893"},"PeriodicalIF":3.9,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148935324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to \"Revealing the effective basal condition of geophysical granular flows\" [International Journal of Multiphase Flow, 198 (2026) 105648]","authors":"Alexis Bougouin,&nbsp;Fabio Dioguardi,&nbsp;Giovanna Capparelli,&nbsp;Eugenio Nicotra,&nbsp;Roberto Sulpizio","doi":"10.1016/j.ijmultiphaseflow.2026.105865","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105865","url":null,"abstract":"<div><span><figure><span><img><ol><li><span><span>Download: <span>Download high-res image (175KB)</span></span></span></li><li><span><span>Download: <span>Download full-size image</span></span></span></li></ol></span></figure></span></div>","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"203 ","pages":"Article 105865"},"PeriodicalIF":3.9,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148935319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical investigation of near-field spray dynamics from flat-fan nozzles for water-based sprayable putty: Effects of nozzle geometry, injection pressure, and thermal thinning temperature","authors":"Lintao Huo,&nbsp;Ce Yang,&nbsp;Haifei Xia,&nbsp;Ying Liu,&nbsp;Yutu Yang,&nbsp;Enyi Ye","doi":"10.1016/j.ijmultiphaseflow.2026.105885","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105885","url":null,"abstract":"<div><div>High-pressure airless spraying is an advanced process that combines high coating efficiency with uniform film thickness formation, and has been applied to the automated putty spray coating of rail vehicle sidewall panels. The atomization angle of the flat-fan nozzle is a critical parameter characterizing the liquid atomization process, directly affecting liquid sheet formation and primary breakup, which in turn governs the momentum, size, and spatial distribution of droplets during secondary breakup, and ultimately determines the deposition behavior on the target surface. As a shear-thinning and thermally thinning non-Newtonian fluid, the atomization quality of putty varies significantly with pressure and temperature. To gain deeper insight into the gas–liquid flow distribution and atomization behavior during putty spraying, numerical simulations of the atomization process of water-based acrylic putty are conducted based on an Eulerian–Lagrangian coupling approach. In this study, the XHD-series flat-fan nozzles are reverse-engineered, and near-field atomization simulations are performed using the VOF model to investigate the relationships between the V-groove geometry parameters — including notch depth and notch angle — and the atomization angle and flow rate. The numerical results are validated against high-speed imaging experiments. The study further systematically examines the spatiotemporal evolution of the flow field, encompassing the development characteristics of the near-field liquid sheet, surface wave fluctuations on the liquid sheet, the formation of the downstream fan-shaped atomization structure, and the wall deposition morphology of the spray.</div></div>","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"203 ","pages":"Article 105885"},"PeriodicalIF":3.9,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148951942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of initial ellipsoidal geometry on droplet deformation and unsteady drag in the bag-breakup regime","authors":"Hongyu Ju,&nbsp;Yue Li,&nbsp;Hongxia Liang,&nbsp;Longxi Zheng,&nbsp;Jianqin Suo","doi":"10.1016/j.ijmultiphaseflow.2026.105847","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105847","url":null,"abstract":"<div><div>The transient deformation of droplets in gas flows is strongly affected by the initial droplet geometry, whereas most previous studies have focused on initially spherical droplets. In this study, large-eddy simulation (LES) coupled with the volume-of-fluid (VOF) method was used to investigate the deformation of initially prolate spheroidal, i.e., ellipsoidal, droplets in the bag-breakup regime, with initial aspect ratios ranging from 1 to 5 and inclination angles ranging from 0° to 90°. The results show that ellipsoidal droplets generally follow a deformation sequence similar to that of spherical droplets, evolving from a disk-like structure toward a bag-like configuration, while the detailed morphology, breakup timing, and breakup mode remain strongly dependent on the initial geometry. A unified piecewise correlation is developed for the evolution of the equivalent windward-face diameter and is found to describe both spherical and ellipsoidal cases reasonably well over the present parameter range. Increasing the initial aspect ratio suppresses the growth of the equivalent windward-face diameter, whereas decreasing the inclination angle enhances it and may promote a transition from bag breakup to bag–stamen breakup. The initial geometry also alters the wake structure and pressure distribution, thereby affecting the unsteady drag response: larger aspect ratios tend to reduce the peak drag level, whereas the inclination angle mainly affects the early drag oscillation through wake asymmetry. Overall, these findings clarify the role of initial nonspherical geometry in droplet deformation and aerodynamic response under bag-breakup conditions, and provide a physical basis for future modeling of droplets with non-spherical initial shapes.</div></div>","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"202 ","pages":"Article 105847"},"PeriodicalIF":3.9,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148641591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of unconventional propeller geometries on tip vortex cavitation noise: A numerical study","authors":"Adrian Portillo-Juan,&nbsp;Simone Saettone,&nbsp;Esteban Ferrer","doi":"10.1016/j.ijmultiphaseflow.2026.105843","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105843","url":null,"abstract":"<div><div>Underwater radiated noise generated by marine propellers has become a major environmental concern, particularly in ecologically sensitive regions such as the Mediterranean Sea. Among the different cavitation regimes, tip vortex cavitation is one of the most persistent and dominant noise sources, often requiring unconventional blade geometries for effective mitigation. This study investigates the influence of tip-raked and toroidal propeller geometries on tip vortex cavitation dynamics and the associated hydroacoustic response. Three propeller configurations were analyzed numerically under cavitating operating conditions using a RANS–DES framework coupled with a VOF cavitation model and a permeable Ffowcs Williams–Hawkings acoustic analogy. The investigated geometries include a conventional baseline propeller, a pressure-side-oriented tip-raked configuration, and a toroidal design derived from the baseline geometry. Results show that both unconventional geometries reduce sound pressure levels by up to 20 dB (ref = 1 <span><math><mi>μ</mi></math></span>Pa) within the 150 Hz–6 kHz range without significant hydrodynamic efficiency losses. The tip-raked propeller suppresses the primary tip vortex and weakens secondary vortex interactions, reducing broadband acoustic emissions. Furthermore, the toroidal configuration completely suppresses coherent tip-vortex cavitation structures and produces the most stable acoustic response among the analyzed cases. Overall, the results demonstrate that unconventional blade-tip geometries can substantially mitigate cavitation-induced noise while preserving propulsive performance, supporting their potential as environmentally sustainable marine propulsion solutions.</div></div>","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"202 ","pages":"Article 105843"},"PeriodicalIF":3.9,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148641592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigation of injection orientation on liquid jet dynamics in supersonic crossflow","authors":"Srinivas M.V.V.,&nbsp;Arun Kumar Rajagopal","doi":"10.1016/j.ijmultiphaseflow.2026.105849","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105849","url":null,"abstract":"<div><div>The present study examines the effect of injector orientation on liquid jet breakup, shock structures, and the associated flow interactions for liquid injection into a Mach 2.1 supersonic crossflow. Three injector configurations with injection angles of 135°, 90°, and 45°are considered. The breakup of the liquid jet analyzed using back-lit imaging show that for the 135° counterflow injection, the liquid jet breaks up very close to the injector exit due to the strong aerodynamic forces imposed by the opposing supersonic crossflow. In contrast, the 45° injection case shows very little breakup because the aerodynamic loading on the liquid column is relatively weaker. The shock structures for different injection cases are studied using shadowgraph imaging over a range of momentum flux ratios (<span><math><msub><mrow><mi>J</mi></mrow><mrow><mi>l</mi></mrow></msub></math></span>). The 135° injection produces a stronger bow shock and further, the interaction of the bow shock with the top wall transitions from regular reflection to Mach reflection at lower <span><math><msub><mrow><mi>J</mi></mrow><mrow><mi>l</mi></mrow></msub></math></span> values compared to other injection cases. The stronger bow shock also leads to a larger upstream separation region and increased liquid entrainment. Dynamic Mode Decomposition further identifies coherent structures governing the jet dynamics, with dominant frequencies matching those obtained from jet interface oscillations and bow shock motion.</div></div>","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"202 ","pages":"Article 105849"},"PeriodicalIF":3.9,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148642055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Influence of dissolved gas concentration on the lifetime of surface bubbles in volatile liquids” [Int. J. Multiph. Flow 196 (2026) 105580]","authors":"Xin Li,&nbsp;Yanshen Li","doi":"10.1016/j.ijmultiphaseflow.2026.105845","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105845","url":null,"abstract":"","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"202 ","pages":"Article 105845"},"PeriodicalIF":3.9,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148642056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to IJMF Article 105740","authors":"T. Daoud,&nbsp;T.L. Jackson,&nbsp;S. Balachandar","doi":"10.1016/j.ijmultiphaseflow.2026.105804","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105804","url":null,"abstract":"","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"202 ","pages":"Article 105804"},"PeriodicalIF":3.9,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148641593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of water droplet on oil films suspended over water bath: Crater and jet dynamics","authors":"Xiaolong He ,&nbsp;Qian Yang ,&nbsp;Haonan Peng ,&nbsp;Linlin Fei ,&nbsp;Jianmin Zhang ,&nbsp;Ya-Ling He","doi":"10.1016/j.ijmultiphaseflow.2026.105644","DOIUrl":"10.1016/j.ijmultiphaseflow.2026.105644","url":null,"abstract":"<div><div>The water droplet impact dynamics on an oil film over the water bath are studied based on extensive experiments, with a focus on the effects of key parameters (droplet size, impact velocity, and oil-film thickness) on the crater growth and the jet formation. A multi-interfaces theory, considering the surface-energy variations of the deformed droplet–air, oil–droplet, and oil–water interfaces, is proposed to describe the total change in the surface energy during the impact, leading to an effective surface tension and Weber number for the following analysis. The maximum crater depth follows a scaling <span><math><mrow><msubsup><mi>d</mi><mi>e</mi><mo>′</mo></msubsup><mo>∼</mo><mrow><mo>(</mo><mrow><mi>F</mi><msup><mrow><mi>r</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>4</mn></mrow></msup><mo>/</mo><msup><mi>ρ</mi><mo>′</mo></msup></mrow><mo>)</mo></mrow></mrow></math></span>, consistent with classical theory, although the crater depth is slightly overestimated for thick oil films due to an underestimation of viscous dissipation. The total crater energy accounts for approximately 27∼35% of the initial droplet impact energy for<span><math><mrow><mrow><mspace></mspace><mtext>Fr</mtext></mrow><mo>≥</mo><mn>100</mn></mrow></math></span>. Furthermore, the maximum jet length scales as <span><math><mrow><msup><mi>l</mi><mo>′</mo></msup><mo>∼</mo><mtext>We</mtext></mrow></math></span>, with jet pinch-off occurring when <span><math><mrow><msup><mi>l</mi><mo>′</mo></msup><mfrac><mo>&gt;</mo><mstyle><mo>∼</mo></mstyle></mfrac><mn>1.24</mn></mrow></math></span>, demonstrating the capability of the proposed multi-interfaces theory to capture crater and jet dynamics. The measured maximum jet length also falls into the classical scaling relationship with the effective Weber number. Finally, two main impact regimes are identified using the effective Weber number <span><math><mrow><mi>W</mi><msub><mi>e</mi><mrow><mi>e</mi><mo>_</mo><mi>h</mi></mrow></msub></mrow></math></span> in combination with the product of the Reynolds and Froude numbers <span><math><mrow><mi>R</mi><mi>e</mi><mi>F</mi><msub><mi>r</mi><mi>h</mi></msub></mrow></math></span>. Generally, the developed multi-interface theory can correctly estimate the effect of the oil layer on the impact dynamics.</div></div>","PeriodicalId":339,"journal":{"name":"International Journal of Multiphase Flow","volume":"198 ","pages":"Article 105644"},"PeriodicalIF":3.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}