English
Related papers

Related papers: Analytical solution of diffusion probability for a…

200 papers

Problems with localized nonhomogeneous material properties present well-known challenges for numerical simulations. In particular, such problems may feature large differences in length scales, causing difficulties with meshing and…

Numerical Analysis · Mathematics 2021-11-23 Alex Viguerie , Silvia Bertoluzza , Alessandro Veneziani , Ferdinando Auricchio

When a flux of Brownian particles is injected in a narrow window located on the surface of a bounded domain, these particles diffuse and can eventually escape through a cluster of narrow windows. At steady-state, we compute asymptotically…

Analysis of PDEs · Mathematics 2024-07-31 Frédéric Paquin-Lefebvre , David Holcman

Experimental measurements of properties of the large-scale circulation (LSC) in turbulent convection of a fluid heated from below in a cylindrical container of aspect ratio one are presented and used to test a model of diffusion in a…

Fluid Dynamics · Physics 2009-11-13 Eric Brown , Guenter Ahlers

We present the detailed analysis of the diffusive transport of spatially inhomogeneous fluid mixtures and the interplay between structural and dynamical properties varying on the atomic scale. The present treatment is based on different…

Mesoscale and Nanoscale Physics · Physics 2011-05-19 Umberto Marini Bettolo Marconi , Simone Melchionna

Traditionally, the quantum Brownian motion is described by Fokker-Planck or diffusion equations in terms of quasi-probability distribution functions, e.g., Wigner functions. These often become singular or negative in the full quantum…

Quantum Physics · Physics 2009-11-07 Suman Kumar Banik , Bidhan Chandra Bag , Deb Shankar Ray

We derive the exact evolution equation for the probability density function of particle displacements generated by arbitrary Gaussian velocity processes, when neither Markovianity and nor stationarity are assumed. Starting from the…

Statistical Mechanics · Physics 2026-05-19 Alessandro Taloni , Gianni Pagnini , Aleksei Chechkin

Self-similar solutions of the coherent diffusion equation are derived and measured. The set of real similarity solutions is generalized by the introduction of a nonuniform phase surface, based on the elegant Gaussian modes of optical…

Quantum Physics · Physics 2015-05-19 O. Firstenberg , P. London , D. Yankelev , R. Pugatch , M. Shuker , N. Davidson

Third-order approximate solutions for surface gravity waves in the finite water depth are studied in the context of potential flow theory. This solution provides explicit expressions for the surface elevation, free-surface velocity…

Fluid Dynamics · Physics 2021-09-15 Zhe Gao , Z. C Sun , S. X Liang

A Langevin process diffusing in a periodic potential landscape has a time dependent diffusion constant which means that its average mean squared displacement (MSD) only becomes linear at late times. The long time, or effective diffusion…

Statistical Mechanics · Physics 2015-06-19 David S. Dean , Gleb Oshanin

In this paper we propose a numerical method to solve the Cauchy problem based on the viscous shallow water equations in an horizontally moving domain. More precisely, we are interested in a flooding and drying model, used to modelize the…

Numerical Analysis · Mathematics 2011-05-09 Bernard Di Martino , Catherine Giacomoni , Jean-Martin Paoli , Pierre Simonnet

The hydrodynamic phase field model is applied to the problem of film spreading on a solid surface. The disjoining potential, responsible for modification of the fluid properties near a three-phase contact line, is computed from the…

Fluid Dynamics · Physics 2009-11-06 Len M. Pismen , Yves Pomeau

A review of solutions of solid-state diffusion problems in infinite and semi-infinite bodies is presented. Based on the identified solutions for the semi-infinite body a two-step diffusion problem is discussed in detail with the first step…

Materials Science · Physics 2023-02-09 Guglielmo Macrelli

We consider classical solutions to the kinetic Fokker-Planck equation on a bounded domain $\mathcal O \subset~\mathbb{R}^d$ in position, and we obtain a probabilistic representation of the solutions using the Langevin diffusion process with…

Probability · Mathematics 2022-03-16 Tony Lelièvre , Mouad Ramil , Julien Reygner

A finite element approach to the elastic flow of a curve coupled with a diffusion equation on the curve is analysed. Considering the graph case, the problem is weakly formulated and approximated with continuous linear finite elements, which…

Numerical Analysis · Mathematics 2017-07-28 Paola Pozzi , Björn Stinner

We consider an incompressible kinetic Fokker Planck equation in the flat torus, which is a simplified version of the Lagrangian stochastic models for turbulent flows introduced by S.B. Pope in the context of computational fluid dynamics.…

Mathematical Physics · Physics 2013-03-19 Mireille Bossy , Joaquin Fontbona , Pierre-Emmanuel Jabin , Jean-François Jabir

The diffusion in two dimensions of non-interacting active particles that follow an arbitrary motility pattern is considered for analysis. Accordingly, the transport equation is generalized to take into account an arbitrary distribution of…

Statistical Mechanics · Physics 2020-09-01 Francisco J. Sevilla

In this paper, we consider a class of discontinuous Galerkin (DG) methods for one-dimensional nonlocal diffusion (ND) problems. The nonlocal models, which are integral equations, are widely used in describing many physical phenomena with…

Numerical Analysis · Mathematics 2024-08-15 Qiang Du , Lili Ju , Jianfang Lu , Xiaochuan Tian

An analytic solution for a Fokker-Planck equation that describes propagation of energetic particles through a scattering medium is obtained. The solution is found in terms of an infinite series of mixed moments of particle distribution. The…

High Energy Astrophysical Phenomena · Physics 2017-02-01 M. A. Malkov

A new method is proposed to numerically extract the diffusivity of a (typically nonlinear) diffusion equation from underlying stochastic particle systems. The proposed strategy requires the system to be in local equilibrium and have…

Statistical Mechanics · Physics 2018-05-09 Peter Embacher , Nicolas Dirr , Johannes Zimmer , Celia Reina

We present a global approach of non-dissipative physics. Based on symplectic mechanics this technique allows us to obtain the solution of a very large class of problems in terms of a Taylor expand. We apply this method to the problem of…

Astrophysics · Physics 2009-10-28 J. Perez , M. Lachieze-Rey