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Related papers: Diffusion-limited mixing by incompressible flows

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Understanding mixing and transport of passive scalars in active fluids is important to many natural (e.g. algal blooms) and industrial (e.g. biofuel, vaccine production) processes. Here, we study the mixing of a passive scalar (dye) in…

Atmospheric water vapour is an essential ingredient of weather and climate. Key features of its distribution can be represented by kinematic models which treat it as a passive scalar advected by a prescribed flow and reacting through…

Atmospheric and Oceanic Physics · Physics 2017-06-29 Yue-Kin Tsang , Jacques Vanneste

We study the compressive diffusion strategies over distributed networks based on the diffusion implementation and adaptive extraction of the information from the compressed diffusion data. We demonstrate that one can achieve a comparable…

Systems and Control · Computer Science 2015-06-18 Muhammed O. Sayin , Suleyman S. Kozat

We introduce Adjoint Sampling, a highly scalable and efficient algorithm for learning diffusion processes that sample from unnormalized densities, or energy functions. It is the first on-policy approach that allows significantly more…

Diffusion models have demonstrated exceptional performances in various fields of generative modeling, but suffer from slow sampling speed due to their iterative nature. While this issue is being addressed in continuous domains, discrete…

Machine Learning · Computer Science 2025-05-12 Satoshi Hayakawa , Yuhta Takida , Masaaki Imaizumi , Hiromi Wakaki , Yuki Mitsufuji

We study mixing and diffusion properties of passive scalars driven by $generic$ rough shear flows. Genericity is here understood in the sense of prevalence and (ir)regularity is measured in the Besov-Nikolskii scale $B^{\alpha}_{1,…

Analysis of PDEs · Mathematics 2023-06-22 Lucio Galeati , Massimiliano Gubinelli

Structures formed by fused filament fabrication are often substantially weaker than those made with conventional techniques, and fail at the welds between successive layers. One factor that may influence strength is flow-induced alignment…

Soft Condensed Matter · Physics 2020-06-30 Marco Aurelio Galvani Cunha , Mark O. Robbins

Behavior of the mixture of particles and dimers moving with different jump rates at reconstructed surfaces is described. Collective diffusion coefficient is calculated by the variational approach. Anisotropy of the collective particle…

Statistical Mechanics · Physics 2014-05-12 Marcin Mińkowski , Magdalena A. Załuska Kotur

A change of solute dispersion regime with the flow velocity has been studied both at the macroscopic and pore scales in a transparent array of capillary channels using an optical technique allowing for simultaneous local and global…

Fluid Dynamics · Physics 2007-05-23 Maria Veronica D'Angelo , Harold Auradou , Catherine Allain , Jean-Pierre Hulin

We propose a PDE-controllability based approach to the enhancement of diffusive mixing for passive scalar fields. Unlike in the existing literature, our relaxation enhancing fields are not prescribed $\textit{ab initio}$ at every time and…

Analysis of PDEs · Mathematics 2025-06-30 Kai Koike , Vahagn Nersesyan , Manuel Rissel , Marius Tucsnak

We consider an elliptic and time-inhomogeneous diffusion process with time-periodic coefficients evolving in a bounded domain of $\mathbb{R}^d$ with a smooth boundary. The process is killed when it hits the boundary of the domain (hard…

Probability · Mathematics 2016-03-22 Pierre Del Moral , Denis Villemonais

We study a two-dimensional diffusive motion of a tracer particle in restricted, crowded anisotropic geometries. The underlying medium is the same as in our previous work [J. Chem. Phys. 140, 044706 (2014)] in which standard, gaussian…

Chemical Physics · Physics 2020-03-17 Michał Cieśla , Bartłomiej Dybiec , Ewa Gudowska-Nowak , Igor Sokolov

High-quality power flow datasets are essential for training machine learning models in power systems. However, security and privacy concerns restrict access to real-world data, making statistically accurate and physically consistent…

Machine Learning · Computer Science 2025-08-26 Milad Hoseinpour , Vladimir Dvorkin

The asymmetries that arise when a mixing layer involves two miscible fluids of differing densities are investigated using incompressible (low-speed) direct numerical simulations. The simulations are performed in the temporal configuration…

Fluid Dynamics · Physics 2021-01-08 Jon R. Baltzer , Daniel Livescu

We consider closed immersed hypersurfaces in $\R^{3}$ and $\R^4$ evolving by a class of constrained surface diffusion flows. Our result, similar to earlier results for the Willmore flow, gives both a positive lower bound on the time for…

Differential Geometry · Mathematics 2012-05-29 James McCoy , Glen Wheeler , Graham Williams

Diffusion models have demonstrated significant potential in achieving state-of-the-art performance across various text generation tasks. In this systematic study, we investigate their application to the table-to-text problem by adapting the…

Computation and Language · Computer Science 2024-09-24 Aleksei S. Krylov , Oleg D. Somov

When injected through a contraction, high molecular weight polymer solutions exhibit a sharp increase of apparent viscosity which originates from stretching polymer chains above a critical extension rate. This chain stretching can also…

Fluid Dynamics · Physics 2020-04-22 Sandeep Garrepally , Stephane Jouenne , Peter D. Olmsted , Francois Lequeux

Depending on their mechanism of self-propulsion, active particles can exhibit a time-dependent, often periodic, propulsion velocity. The precise propulsion velocity profile determines their mean square displacement and their effective…

Soft Condensed Matter · Physics 2024-05-06 Arnau Jurado Romero , Carles Calero , Rossend Rey

The diffusion of a particle in a crowded environment typically proceeds through three regimes: for very short times the particle diffuses freely until it collides with an obstacle for the first time, while for very long times diffusion the…

Biological Physics · Physics 2019-10-09 Nguiya P. Neo , Gary W. Slater

We analyse how simple local constraints in two dimensions lead a defect to exhibit robust, non-transient, and tunable, subdiffusion. We uncover a rich dynamical phenomenology realised in ice- and dimer-type models. On the microscopic scale…

Mesoscale and Nanoscale Physics · Physics 2025-04-02 Nilotpal Chakraborty , Markus Heyl , Roderich Moessner