English
Related papers

Related papers: Non-negative mixed finite element formulations for…

200 papers

We present a robust computational framework for advective-diffusive-reactive systems that satisfies maximum principles, the non-negative constraint, and element-wise species balance property. The proposed methodology is valid on general…

Numerical Analysis · Mathematics 2015-11-10 M. K. Mudunuru , K. B. Nakshatrala

Preservation of the maximum principle is studied for the combination of the linear finite element method in space and the $\theta$-method in time for solving time dependent anisotropic diffusion problems. It is shown that the numerical…

Numerical Analysis · Mathematics 2013-10-23 Xianping Li , Weizhang Huang

We propose two different discrete formulations for the weak imposition of the Neumann boundary conditions of the Darcy flow. The Raviart-Thomas mixed finite element on both triangular and quadrilateral meshes is considered for both methods.…

Numerical Analysis · Mathematics 2021-04-06 Erik Burman , Riccardo Puppi

We consider three types of subdiffusion models, namely single-term, multi-term and distributed order fractional diffusion equations, for which the maximum-principle holds and which, in particular, preserve nonnegativity. Hence the solution…

Numerical Analysis · Mathematics 2015-10-13 Bangti Jin , Raytcho Lazarov , Vidar Thomée , Zhi Zhou

We consider an elliptic partial differential equation in non-divergence form with a random diffusion matrix and random forcing term. To address this, we propose a mixed-type continuous finite element discretization in the physical domain,…

Numerical Analysis · Mathematics 2025-12-04 Amireh Mousavi

The main aim of this paper is to document the performance of $p$-refinement with respect to maximum principles and the non-negative constraint. The model problem is (steady-state) anisotropic diffusion with decay (which is a second-order…

Numerical Analysis · Computer Science 2015-03-19 G. S. Payette , K. B. Nakshatrala , J. N. Reddy

We present a novel computational framework for diffusive-reactive systems that satisfies the non-negative constraint and maximum principles on general computational grids. The governing equations for the concentration of reactants and…

Numerical Analysis · Computer Science 2015-06-11 K. B. Nakshatrala , M. K. Mudunuru , A. J. Valocchi

A mesh condition is developed for linear finite element approximations of anisotropic diffusion-convection-reaction problems to satisfy a discrete maximum principle. Loosely speaking, the condition requires that the mesh be simplicial and…

Numerical Analysis · Mathematics 2014-06-23 Changna Lu , Weizhang Huang , Jianxian Qiu

The finite element solution of two-dimensional anisotropic diffusion problems is considered. A Delaunay-type mesh condition is developed for linear finite element approximations to satisfy a discrete maximum principle. The condition is…

Numerical Analysis · Mathematics 2011-06-27 Weizhang Huang

It is well-known that the standard Galerkin formulation, which is often the formulation of choice under the finite element method for solving self-adjoint diffusion equations, does not meet maximum principles and the non-negative constraint…

Numerical Analysis · Computer Science 2018-02-22 J. Chang , S. Karra , K. B. Nakshatrala

In this paper, we develop a modified nonlinear dynamic diffusion (DD) finite element method for convection-diffusion-reaction equations. This method is free of stabilization parameters and is capable of precluding spurious oscillations. We…

Numerical Analysis · Mathematics 2025-03-11 Shaohong Du , Qianqian Hou , Xiaoping Xie

Standard finite element discretizations of the Richards equation may violate the discrete minimum principle, producing unphysical negative saturations. While existing bound-preserving methods typically rely on computationally expensive…

Numerical Analysis · Mathematics 2026-05-12 Abderrahmane Benfanich , Yves Bourgault , Abdelaziz Beljadid

We establish an a priori error analysis for the lowest-order Raviart-Thomas finite element discretisation of the nonlinear Gross-Pitaevskii eigenvalue problem. Optimal convergence rates are obtained for the primal and dual variables as well…

Numerical Analysis · Mathematics 2024-02-12 Dietmar Gallistl , Moritz Hauck , Yizhou Liang , Daniel Peterseim

We consider primal-dual mixed finite element methods for the advection--diffusion equation. For the primal variable we use standard continuous finite element space and for the flux we use the Raviart-Thomas space. We prove optimal a priori…

Numerical Analysis · Mathematics 2021-06-01 Erik Burman , Cuiyu He

Transient diffusion equations arise in many branches of engineering and applied sciences (e.g., heat transfer and mass transfer), and are parabolic partial differential equations. It is well-known that, under certain assumptions on the…

Numerical Analysis · Computer Science 2013-08-06 K. B. Nakshatrala , H. Nagarajan , M. Shabouei

We study mixed finite element methods for the rotating shallow water equations with linearized momentum terms but nonlinear drag. By means of an equivalent second-order formulation, we prove long-time stability of the system without energy…

Numerical Analysis · Mathematics 2017-06-06 Colin J. Cotter , P. Jameson Graber , Robert C. Kirby

We are concerned with the study of the well-posedness of a nonlinear diffusion equation with a monotonically increasing multivalued time-dependent nonlinearity derived from a convex continuous potential having a superlinear growth to…

Analysis of PDEs · Mathematics 2013-07-09 Gabriela Marinoschi

A numerical method for approximating weak solutions of an aggregation equation with degenerate diffusion is introduced. The numerical method consists of a stabilized finite element method together with a mass lumping technique and an extra…

A hydrogeological model for the spread of pollution in an aquifer is considered. The model consists in a convection-diffusion-reaction equation involving the dispersion tensor which depends nonlinearly of the fluid velocity. We introduce an…

Numerical Analysis · Mathematics 2020-06-05 Éloïse Comte

We consider a model convection-diffusion problem and present our recent numerical and analysis results regarding mixed finite element formulation and discretization in the singular perturbed case when the convection term dominates the…

Numerical Analysis · Mathematics 2024-02-07 Constantin Bacuta , Daniel Hayes , Tyler O'Grady
‹ Prev 1 2 3 10 Next ›