Physica D: Nonlinear Phenomena最新文献_第10页

Alignment of geophysical fields: A differential geometry perspective 地球物理场对准：微分几何视角

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-10-30 DOI: 10.1016/j.physd.2025.134997

Yicun Zhen , Valentin Resseguier , Bertrand Chapron

引用次数: 0

Hydrodynamic stability of convection in porous medium with chemical reaction effect and generalised boundary conditions 具有化学反应效应和广义边界条件的多孔介质对流流体动力稳定性

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-10-24 DOI: 10.1016/j.physd.2025.135007

Sanaa L. Khalaf, Akil J. Harfash

{"title":"Hydrodynamic stability of convection in porous medium with chemical reaction effect and generalised boundary conditions","authors":"Sanaa L. Khalaf, Akil J. Harfash","doi":"10.1016/j.physd.2025.135007","DOIUrl":"10.1016/j.physd.2025.135007","url":null,"abstract":"<div><div>We study solutal convection in a Brinkman porous layer with generalised Robin boundary conditions for solute concentration and two-sided Navier slip for velocity. The linear onset threshold (<span><math><mrow><mi>R</mi><msub><mrow><mi>a</mi></mrow><mrow><mi>L</mi></mrow></msub></mrow></math></span>) and the global energy threshold (<span><math><mrow><mi>R</mi><msub><mrow><mi>a</mi></mrow><mrow><mi>E</mi></mrow></msub></mrow></math></span>) are determined using a new Chebyshev collocation algorithm coupled to a pseudoinverse–eigenvalue formulation and a golden–section search. Accuracy is assessed through residual evaluation, as no analytical solutions are available for this problem. The results reveal that the Brinkman coefficient <span><math><mi>λ</mi></math></span> exerts a nearly linear stabilising influence on both <span><math><mrow><mi>R</mi><msub><mrow><mi>a</mi></mrow><mrow><mi>L</mi></mrow></msub></mrow></math></span> and <span><math><mrow><mi>R</mi><msub><mrow><mi>a</mi></mrow><mrow><mi>E</mi></mrow></msub></mrow></math></span>, while the slip coefficients <span><math><msub><mrow><mi>N</mi></mrow><mrow><mi>L</mi></mrow></msub></math></span> and <span><math><msub><mrow><mi>N</mi></mrow><mrow><mi>U</mi></mrow></msub></math></span> act asymmetrically to destabilise the system. In addition, the interaction between the reaction parameter <span><math><mi>ζ</mi></math></span> and the concentration ratio <span><math><mi>η</mi></math></span> produces non-monotonic shifts in the stability thresholds. These findings clarify how reaction, solute exchange, and interfacial slip reshape both linear and nonlinear stability boundaries in Brinkman porous media, and they establish a high-accuracy computational framework for analysing stability regimes relevant to reactive transport.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"483 ","pages":"Article 135007"},"PeriodicalIF":2.9,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145416514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quadruplet form of water waves kinetic equation 水波动力学方程的四重态形式

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-10-14 DOI: 10.1016/j.physd.2025.134977

V. Geogjaev

引用次数: 0

A new mathematical model for cell motility with nonlocal repulsion from saturated areas 饱和区非局部排斥作用下细胞运动的新数学模型

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-10-22 DOI: 10.1016/j.physd.2025.134973

Carlo Giambiagi Ferrari, Francisco Guillén-González, Mayte Pérez-Llanos, Antonio Suárez

引用次数: 0

On the Hamiltonian structure of the intrinsic evolution of a closed vortex sheet 闭涡片内禀演化的哈密顿结构

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-10-15 DOI: 10.1016/j.physd.2025.134978

Banavara N. Shashikanth

引用次数: 0

Flexible evolution of flocking tracking for a nonlinear collective migration model with heterogeneous transmission delays 具有异构传输延迟的非线性群体迁移模型的柔性演化

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-09-12 DOI: 10.1016/j.physd.2025.134927

Yipeng Chen, Yicheng Liu, Xiao Wang

{"title":"Flexible evolution of flocking tracking for a nonlinear collective migration model with heterogeneous transmission delays","authors":"Yipeng Chen, Yicheng Liu, Xiao Wang","doi":"10.1016/j.physd.2025.134927","DOIUrl":"10.1016/j.physd.2025.134927","url":null,"abstract":"<div><div>Division of labour and cooperation in animal groups is an external manifestation of swarm intelligence, such as leaders and followers in collective migration of animals. In this paper, we propose a nonlinear multi-agent system named collective migration model and try to build a more realistic dynamic leader–follower structure that facilitates flexible evolution of flocking tracking. The model highlights individual heterogeneity, especially including heterogeneous transmission delays among agents and heterogeneous parameters called tracking strategies that establish a trade-off between alignment and tracking for each agent, and essentially determine the leader–follower structure of the system. By constructing dynamic upper bounds of velocity, setting tracking periods and partitioning state space, a time-varying tracking strategy vector is designed to produce a dynamic leader–follower structure in which the system has a flexible configuration and can achieve flocking tracking for any initial state. The increase of transmission delay prolongs the switching cycle of leader–follower structure, and decreases the convergence speed of the system. An algorithm of the tracking strategy vector and several numerical simulations are provided to verify our results.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"483 ","pages":"Article 134927"},"PeriodicalIF":2.9,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145047384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Magnus exponential integrators for stiff time-varying stochastic systems 刚性时变随机系统的Magnus指数积分器

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-11-11 DOI: 10.1016/j.physd.2025.135034

Dev Jasuja , P.J. Atzberger

引用次数: 0

Quantifying the temporal-spatial transition of rayleigh-taylor mixing 瑞利-泰勒混合的时空转换量化

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-10-11 DOI: 10.1016/j.physd.2025.134975

Han Qi (齐涵) , Zhiwei He (何志伟) , Aiguo Xu (许爱国) , Yousheng Zhang (张又升)

{"title":"Quantifying the temporal-spatial transition of rayleigh-taylor mixing","authors":"Han Qi (齐涵) , Zhiwei He (何志伟) , Aiguo Xu (许爱国) , Yousheng Zhang (张又升)","doi":"10.1016/j.physd.2025.134975","DOIUrl":"10.1016/j.physd.2025.134975","url":null,"abstract":"<div><div>In fusion engineering, the mixing transition induced by Rayleigh-Taylor (RT) instability significantly influences mixing evolution, necessitating accurate prediction of both temporal and spatial characteristics. However, the transition is a strong nonlinear process, and it is hard to accurately characterize and model the spatial-temporal transition. To address the challenges, we perform implicit large-eddy simulations of RT mixing across various density ratios. To comprehensively capture both temporal and spatial dynamics, this study proposes a novel approach by leveraging the evolution of flow structures as the foundation for characterizing a temporal-spatial transition process. The transition process is inherently linked to the evolution of flow structures, leading to the introduction of the intermittency factor <span><math><mi>γ</mi></math></span>, which quantifies the probability of turbulent events generated by these structures of transition. A specialized methodology for extracting <span><math><mi>γ</mi></math></span> in RT mixing is developed and the evolution of <span><math><mi>γ</mi></math></span> is analyzed. The temporal evolution of <span><math><mi>γ</mi></math></span> reveals the basic mechanism of the onset of transition and turbulence and its spatial distribution can reflect the relationship between turbulence, mixing and entrainment. Ultimately, we have uncovered a scaling law for the temporal evolution and a universal quantitative formula for the spatial characteristics of the transition process, both of which are independent of the density ratio.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"483 ","pages":"Article 134975"},"PeriodicalIF":2.9,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145362845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulations of Richtmyer–Meshkov instabilities using a stochastic front tracking method 基于随机前沿跟踪方法的richmyer - meshkov不稳定性模拟

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-10-17 DOI: 10.1016/j.physd.2025.134981

Olivier Hurisse , James Glimm , Philippe Helluy

引用次数: 0

Coupled stochastic-statistical equations for filtering multiscale turbulent systems 滤波多尺度湍流系统的耦合随机-统计方程

IF 2.9 3区数学

Physica D: Nonlinear Phenomena Pub Date : 2025-12-01 Epub Date: 2025-10-31 DOI: 10.1016/j.physd.2025.135013

Di Qi , Jian-Guo Liu

{"title":"Coupled stochastic-statistical equations for filtering multiscale turbulent systems","authors":"Di Qi , Jian-Guo Liu","doi":"10.1016/j.physd.2025.135013","DOIUrl":"10.1016/j.physd.2025.135013","url":null,"abstract":"<div><div>We present a new strategy for the statistical forecasts of multiscale nonlinear systems involving non-Gaussian probability distributions with the help of observation data from leading-order moments. A stochastic-statistical modeling framework is designed to enable systematic theoretical analysis and support efficient numerical simulations. The nonlinear coupling structures of the explicit stochastic and statistical equations are exploited to develop a new multiscale filtering system using statistical observation data, which is represented by an infinite-dimensional Kalman–Bucy filter satisfying conditional Gaussian dynamics. To facilitate practical implementation, a finite-dimensional stochastic filtering model is proposed that approximates the intractable infinite-dimensional filter solution. We prove that this approximating filter effectively captures key non-Gaussian features, demonstrating consistent statistics with the optimal filter first in its analysis step update, then at the long-time limit guaranteeing stable convergence to the optimal filter. Finally, we build a practical ensemble filter algorithm based on the stochastic filtering model. Robust performance of the modeling and filtering strategies is demonstrated on prototype models, implying wider applications on challenging problems in statistical prediction and uncertainty quantification of multiscale turbulent states.</div></div>","PeriodicalId":20050,"journal":{"name":"Physica D: Nonlinear Phenomena","volume":"484 ","pages":"Article 135013"},"PeriodicalIF":2.9,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145475983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0