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Related papers: Timestep control for weakly instationary flows

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An adaptive BDF2 implicit time-stepping method is analyzed for the phase field crystal model. The suggested method is proved to preserve a modified energy dissipation law at the discrete levels if the time-step ratios…

Numerical Analysis · Mathematics 2020-12-22 Hong-lin Liao , Bingquan Ji , Luming Zhang

We revisit, both numerically and analytically, the finite-time blowup of the infinite-energy solution of 3D Euler equations of stagnation-point-type introduced by Gibbon et al. (1999). By employing the method of mapping to regular systems,…

Fluid Dynamics · Physics 2016-04-20 Rachel M. Mulungye , Dan Lucas , Miguel D. Bustamante

Invariant solutions of the Navier-Stokes equations play an important role in the spatiotemporally chaotic dynamics of turbulent shear flows. Despite the significance of these solutions, their identification remains a computational…

Fluid Dynamics · Physics 2023-10-11 Omid Ashtari , Tobias M. Schneider

We propose a deterministic adjoint matching framework that formulates human preference alignment for flow-based generative models as an optimal control problem over velocity fields. One can directly regress the control toward a…

Artificial Intelligence · Computer Science 2026-05-08 Zhengyi Guo , Jiayuan Sheng , David D. Yao , Wenpin Tang

The rarefied flow and multi-scale flow are crucial for the aerodynamic design of spacecraft, ultra-low orbital vehicles and plumes. By introducing a discrete velocity space, the Boltzmann method, such as the discrete velocity method and…

Fluid Dynamics · Physics 2025-04-07 Jianfeng Chen , Sha Liu , Rui Zhang , Chengwen Zhong , Yanguang Yang , Congshan Zhuo

We derive a new parallel-in-time approach for solving large-scale optimization problems constrained by time-dependent partial differential equations arising from fluid dynamics. The solver involves the use of a block circulant approximation…

Numerical Analysis · Mathematics 2024-05-30 Bernhard Heinzelreiter , John W. Pearson

The space-time adaptive ADER finite element DG method with a posteriori correction technique of solutions on subcells by the finite-volume ADER-WENO limiter was used to simulate non-stationary compressible multicomponent reactive flows. The…

Fluid Dynamics · Physics 2024-09-17 I. S Popov

A new discrete-velocity model is presented to solve the three-dimensional Euler equations. The velocities in the model are of an adaptive nature---both the origin of the discrete-velocity space and the magnitudes of the discrete-velocities…

comp-gas · Physics 2009-10-28 Balu Nadiga

We propose an adaptive numerical solver for the study of viscoelastic 2D two-phase flows using the volume-of-fluid method. The scheme uses the robust log conformation tensor technique of Fattal & Kupferman (2004,2005} combined with the…

Fluid Dynamics · Physics 2018-07-03 J. M. Lopez-Herrera , S. Popinet , A. A. Castrejon-Pita

The potential of the hybridized discontinuous Galerkin (HDG) method has been recognized for the computation of stationary flows. Extending the method to time-dependent problems can, e.g., be done by backward difference formulae (BDF) or…

Numerical Analysis · Mathematics 2014-06-03 Alexander Jaust , Jochen Schütz

The present work is devoted to introduce the backward Euler based modular time filter method for MHD flow. The proposed method improves the accuracy of the solution without a significant change in the complexity of the system. Since time…

Numerical Analysis · Mathematics 2019-06-20 Aytekin Cibik , Fatma G. Eroglu , Songul Kaya

Recently the second and third author developed an iterative scheme for obtaining rough solutions of the 3D incompressible Euler equations in H\"older spaces (arXiv:1202.1751 and arXiv:1205.3626 (2012)). The motivation comes from Onsager's…

Analysis of PDEs · Mathematics 2013-12-12 Tristan Buckmaster , Camillo De Lellis , László Székelyhidi

ODE solvers with randomly sampled timestep sizes appear in the context of chaotic dynamical systems, differential equations with low regularity, and, implicitly, in stochastic optimisation. In this work, we propose and study the stochastic…

Numerical Analysis · Mathematics 2024-08-05 Jonas Latz

We introduce a class of adaptive timestepping strategies for stochastic differential equations with non-Lipschitz drift coefficients. These strategies work by controlling potential unbounded growth in solutions of a numerical scheme due to…

Numerical Analysis · Mathematics 2016-10-14 Cónall Kelly , Gabriel J. Lord

We introduce a novel positivity-preserving, parameter-free numerical stabilisation approach for high-order discontinuous spectral element approximations of compressible multi-species flows. The underlying stabilisation method is the…

Fluid Dynamics · Physics 2023-08-07 Will Trojak , Tarik Dzanic

We consider a velocity tracking problem for stochastic Navier-Stokes equations in a 2D-bounded domain. The control acts on the boundary through an injection-suction device with uncertainty, which acts in accordance with the non-homogeneous…

Probability · Mathematics 2024-09-04 Nikolai Chemetov , Fernanda Cipriano

This work serves as a primer to our efforts in arriving at convergence estimates for the fixed stress split iterative scheme for single phase flow coupled with small strain anisotropic poroelastoplasticity. The fixed stress split iterative…

Numerical Analysis · Mathematics 2018-10-11 Saumik Dana , Mary F. Wheeler

This article presents stability and convergence analyses of subgrid multiscale stabilized finite element formulation of non-Newtonian power-law fluid flow model strongly coupled with variable coefficients Advection-Diffusion-Reaction…

Numerical Analysis · Mathematics 2021-02-19 Manisha Chowdhury , B. V. Rathish Kumar

We are interested in the stability analysis of two-dimensional incompressible inviscid fluids. Specifically, we revisit a recent result on the stability of Yudovich's solutions to the incompressible Euler equations in $L^\infty([0,T];H^1)$…

Analysis of PDEs · Mathematics 2023-12-25 Diogo Arsénio , Haroune Houamed

We consider the solution of the fully kinetic (including electrons) Vlasov-Amp\`ere system in a one-dimensional physical space and two-dimensional velocity space (1D-2V) for an arbitrary number of species with a time-implicit Eulerian…

Plasma Physics · Physics 2020-07-13 Steven E. Anderson , William T. Taitano , Luis Chacón , Andrei N. Simakov