English
Related papers

Related papers: Multirate partially explicit scheme for multiscale…

200 papers

Many applications of computational fluid dynamics require multiple simulations of a flow under different input conditions. In this paper, a numerical algorithm is developed to efficiently determine a set of such simulations in which the…

Numerical Analysis · Mathematics 2017-05-29 Max Gunzburger , Nan Jiang , Zhu Wang

We present an ``equation-free'' multiscale approach to the simulation of unsteady diffusion in a random medium. The diffusivity of the medium is modeled as a random field with short correlation length, and the governing equations are cast…

Numerical Analysis · Mathematics 2007-05-23 Dongbin Xiu , Ioannis Kevrekidis

In this paper we develop a class of Implicit-Explicit Runge-Kutta schemes for solving the multi-scale semiconductor Boltzmann equation. The relevant scale which characterizes this kind of problems is the diffusive scaling. This means that,…

Numerical Analysis · Mathematics 2016-08-24 G. Dimarco , L. Pareschi , V. Rispoli

Convergence failure and slow convergence rates are among the biggest challenges with solving the system of non-linear equations numerically. Although mitigated, such issues still linger when using strictly small time steps and…

Numerical Analysis · Mathematics 2019-12-05 Hanyu Li , Wing Tat Leung , Mary F. Wheeler

Many complex applications require the solution of initial-value problems where some components change fast, while others vary slowly. Multirate schemes apply different step sizes to resolve different components of the system, according to…

Numerical Analysis · Mathematics 2021-02-23 Michael Guenther , Adrian Sandu

In order to treat the multiple time scales of ocean dynamics in an efficient manner, the baroclinic-barotropic splitting technique has been widely used for solving the primitive equations for ocean modeling. Based on the framework of strong…

Numerical Analysis · Mathematics 2022-03-14 Rihui Lan , Lili Ju , Zhu Wang , Max Gunzburger , Philip Jones

In this paper, we propose a local model reduction approach for subsurface flow problems in stochastic and highly heterogeneous media. To guarantee the mass conservation, we consider the mixed formulation of the flow problem and aim to solve…

Numerical Analysis · Mathematics 2022-03-23 Yiran Wang , Eric Chung , Shubin Fu

Multirate time integration methods apply different step sizes to resolve different components of the system based on the local activity levels. This local selection of step sizes allows increased computational efficiency while achieving the…

Numerical Analysis · Computer Science 2021-12-22 Arash Sarshar , Steven Roberts , Adrian Sandu

The paper investigates a non-intrusive parallel time integration with multigrid for space-fractional diffusion equations in two spatial dimensions. We firstly obtain a fully discrete scheme via using the linear finite element method to…

Numerical Analysis · Mathematics 2018-05-18 Xiaoqiang Yue , Shi Shu , Xiaowen Xu , Weiping Bu , Kejia Pan

We propose second-order implicit-explicit (IMEX) time-stepping schemes for nonlinear fractional differential equations with fractional order $0<\beta<1$. From the known structure of the non-smooth solution and by introducing corresponding…

Numerical Analysis · Mathematics 2016-08-03 Wanrong Cao , Fanhai Zeng , Zhongqiang Zhang , George Em Karniadakis

We consider the problem of statistical inference for the effective dynamics of multiscale diffusion processes with (at least) two widely separated characteristic time scales. More precisely, we seek to determine parameters in the effective…

Statistics Theory · Mathematics 2013-05-30 Sebastian Krumscheid , Grigorios A. Pavliotis , Serafim Kalliadasis

New implicit and implicit-explicit time-stepping methods for the wave equation in second-order form are described with application to two and three-dimensional problems discretized on overset grids. The implicit schemes are single step,…

Numerical Analysis · Mathematics 2024-04-24 Allison M. Carson , Jeffrey W. Banks , William D. Henshaw , Donald W. Schwendeman

In this work, we propose a simple numerical scheme based on a fast front-tracking approach for solving a fluid-structure interaction (FSI) problem of plaque growth in blood vessels. A rigorous error analysis is carried out for the temporal…

Numerical Analysis · Mathematics 2023-07-24 Zhaoyang Wang , Ping Lin

Two phase flows that include phase transition, especially phase creation, with a sharp interface remain a challenging task for numerics. We consider the isothermal Euler equations with phase transition between a liquid and a vapor phase.…

Numerical Analysis · Mathematics 2022-11-03 Sandra May , Ferdinand Thein

In this paper, a second order finite difference scheme is investigated for time-dependent one-side space fractional diffusion equations with variable coefficients. The existing schemes for the equation with variable coefficients have…

Numerical Analysis · Mathematics 2019-02-25 Xue-lei Lin , Pin Lyu , Michael K. Ng , Hai-Wei Sun , Seakweng Vong

When modeling astrophysical fluid flows, it is often appropriate to discard the canonical magnetohydrodynamic approximation thereby freeing the magnetic field to diffuse with respect to the bulk velocity field. As a consequence, however,…

Astrophysics · Physics 2009-11-13 Stephen O'Sullivan , Turlough P. Downes

We consider systems of ordinary differential equations with multiple scales in time. In general, we are interested in the long time horizon of a slow variable that is coupled to solution components that act on a fast scale. Although the…

Numerical Analysis · Mathematics 2021-04-28 Leopold Lautsch , Thomas Richter

Despite the growing interest in parallel-in-time methods as an approach to accelerate numerical simulations in atmospheric modelling, improving their stability and convergence remains a substantial challenge for their application to…

Numerical Analysis · Mathematics 2023-10-27 João Guilherme Caldas Steinstraesser , Pedro da Silva Peixoto , Martin Schreiber

Explicit stabilized methods are highly efficient time integrators for large and stiff systems of ordinary differential equations especially when applied to semi-discrete parabolic problems. However, when local spatial mesh refinement is…

Numerical Analysis · Mathematics 2025-10-20 Mathieu Benninghoff , Gilles Vilmart

Difference schemes for the time-fractional diffusion equation with variable coefficients and nonlocal boundary conditions containing real parameters $\alpha$ and $\beta$ are considered. By the method of energy inequalities, for the solution…

Numerical Analysis · Mathematics 2015-03-27 A. A. Alikhanov