English
Related papers

Related papers: An analytical solution for vertical infiltration i…

200 papers

A numerical technique is described that can efficiently compute solutions in interface problems. These are problems with data, such as the coefficients of differential equations, discontinuous or even singular across one or more interfaces.…

Computational Physics · Physics 2015-05-27 Theodoros P. Horikis

In this paper, we use the unified transform method to consider the initial-boundary value problem for the coupled Fokas-Lenells equations on the half-line, assuming that the solution $\{q(x,t),r(x,t)\}$ of the coupled Fokas-Lenells…

Mathematical Physics · Physics 2017-11-21 Beibei Hu , Tiecheng Xia

Modeling unsaturated flow through soils with water uptake by plan root has many applications in agriculture and water resources management. In this study, our aim is to develop efficient numerical techniques for solving the Richards…

Numerical Analysis · Mathematics 2024-04-16 Mohamed Boujoudar , Abdelaziz Beljadid , Ahmed Taik

Binary-fluid flows can be modeled using the Navier-Stokes-Cahn-Hilliard equations, which represent the boundary between the fluid constituents by a diffuse interface. The diffuse-interface model allows for complex geometries and topological…

We study an initial value problem for the one-dimensional non-stationary linear Schr\"odinger equation with a point singular potential. In our approach, the problem is considered as a system of coupled initial-boundary value (IBV) problems…

Analysis of PDEs · Mathematics 2020-04-14 Yan Rybalko

A non-conventional shape optimization approach is introduced to address the identification of an obstacle immersed in a fluid described by the Stokes equation within a larger bounded domain, relying on boundary measurements on the…

Optimization and Control · Mathematics 2024-03-19 Julius Fergy Tiongson Rabago , Lekbir Afraites , Hirofumi Notsu

We consider the unified transform method, also known as the Fokas method, for solving partial differential equations. We adapt and modify the methodology, incorporating new ideas where necessary, in order to apply it to solve a large class…

Analysis of PDEs · Mathematics 2018-08-28 Arran Fernandez , Dumitru Baleanu , Athanassios S. Fokas

In this note, the existing porousMultiphaseFoam toolbox, developed initially for any two-phase flow in porous media is extended to the specific case of the Richards' equation which neglect the pressure gradient of the non-wetting phase.…

Computational Engineering, Finance, and Science · Computer Science 2015-10-07 Pierre Horgue , Jacques Franc , Romain Guibert , Gérald Debenest

Boundary integral methods are highly suited for problems with complicated geometries, but require special quadrature methods to accurately compute the singular and nearly singular layer potentials that appear in them. This paper presents a…

Numerical Analysis · Mathematics 2022-08-24 Joar Bagge , Anna-Karin Tornberg

By employing a novel generalization of the inverse scattering transform method known as the unified transform or Fokas method, it can be shown that the solution of certain physically significant boundary value problems for the elliptic…

Analysis of PDEs · Mathematics 2020-02-14 J. Lenells , A. S. Fokas

In this work it is shown how the immersed boundary method of (Peskin2002) for modeling flexible structures immersed in a fluid can be extended to include thermal fluctuations. A stochastic numerical method is proposed which deals with…

Soft Condensed Matter · Physics 2023-02-28 P. J. Atzberger , P. R. Kramer , C. S. Peskin

We present a robust optimisation framework for computing invariant solutions of wall-bounded flows by recasting the Navier-Stokes equations as a variational problem as established in Ashtari and Schneider, JFM (2023). The approach minimises…

Fluid Dynamics · Physics 2026-04-14 Thomas Burton , Sean Symon , Davide Lasagna

Initial-boundary value problems for 1-dimensional `completely integrable' equations can be solved via an extension of the inverse scattering method, which is due to Fokas and his collaborators. A crucial feature of this method is that it…

Analysis of PDEs · Mathematics 2016-09-07 Dimitra C. Antonopoulou , Spyridon Kamvissis

Flow in variably saturated porous media is typically modelled by the Richards equation, a nonlinear elliptic-parabolic equation which is notoriously challenging to solve numerically. In this paper, we propose a robust and fast iterative…

Numerical Analysis · Mathematics 2023-01-06 Jakob S. Stokke , Koondanibha Mitra , Erlend Storvik , Jakub W. Both , Florin A. Radu

In this paper, we consider the initial-boundary value problem of the Kundu-Eckhaus equation on the half-line by using of the Fokas unified transform method. Assuming that the solution $u(x,t)$ exists, we show that it can be expressed in…

Exactly Solvable and Integrable Systems · Physics 2017-11-27 Beibei Hu , Tiecheng Xia , Ning Zhang

We present a point set registration method in bounded domains based on the solution to the Fokker Planck equation. Our approach leverages (i) density estimation based on Gaussian mixture models; (ii) a stabilized finite element…

Numerical Analysis · Mathematics 2024-12-13 Angelo Iollo , Tommaso Taddei

Fluid flow in the vadose zone is governed by Richards equation; it is parameterized by hydraulic conductivity, which is a nonlinear function of pressure head. Investigations in the vadose zone typically require characterizing distributed…

Geophysics · Physics 2022-03-29 Rowan Cockett , Lindsey J. Heagy , Eldad Haber

We develop an immersed boundary (IB) method for modeling flows around fixed or moving rigid bodies that is suitable for a broad range of Reynolds numbers, including steady Stokes flow. The spatio-temporal discretization of the fluid…

Numerical Analysis · Mathematics 2016-03-02 B. Kallemov , A. Pal Singh Bhalla , B. E. Griffith , A. Donev

We introduce a method-of-lines formulation of the closest point method, a numerical technique for solving partial differential equations (PDEs) defined on surfaces. This is an embedding method, which uses an implicit representation of the…

Numerical Analysis · Mathematics 2013-07-23 Ingrid von Glehn , Thomas März , Colin B. Macdonald

We develop a new approach to solve the nonlinear Richards equation based on the Kirchhoff transformation and localized radial basis function (LRBF) techniques. Our aim is to reduce the nonlinearity of the governing equation and apply LRBF…

Numerical Analysis · Mathematics 2022-11-18 Mohamed Boujoudar , Abdelaziz Beljadid , Ahmed Taik