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Related papers: Mixing and reaction efficiency in closed domains

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We analyze the dynamics of solute mixing in a vortex flow. The transport of a passive tracer is considered in a Rankine vortex. The action of a shear flow, in general, is to achieve stretching of fluid elements. A vortex flow exhibits…

Fluid Dynamics · Physics 2020-03-02 Sabyasachi Sen , Prajwal , Joris Heyman , Tanguy Le Borgne , Aditya Bandopadhyay

This paper presents a millisecond-level look-ahead control algorithm for energy storage with constant space complexity and worst-case linear run-time complexity. The algorithm connects the optimal control with the Lagrangian multiplier…

Optimization and Control · Mathematics 2019-12-13 Bolun Xu , Magnus Korpas , Audun Botterud , Francis O'Sullivan

We design and compute a class of optimal control problems for reaction-diffusion systems. They form mean field control problems related to multi-density reaction-diffusion systems. To solve proposed optimal control problems numerically, we…

Optimization and Control · Mathematics 2023-06-13 Guosheng Fu , Stanley Osher , Will Pazner , Wuchen Li

In this paper we present a numerical study on control and observation of traffic flow using Lagrangian measurements and actuators. We investigate the effect of some basic control and observation schemes using probe and actuated vehicles…

Optimization and Control · Mathematics 2020-10-07 Mladen Cicic , Matthieu Barreau , Karl Henrik Johansson

The Lagrangian properties of the velocity field in a magnetized fluid are studied using three-dimensional simulations of a helical magnetohydrodynamic dynamo. We compute the attracting and repelling Lagrangian coherent structures, which are…

Solar and Stellar Astrophysics · Physics 2012-07-10 Erico L. Rempel , Abraham C. -L. Chian , Axel Brandenburg

We study cooperative control dynamics with gradient based forcing terms. As a specific example, we focus on source-seeking dynamics with vehicles embedded in an unknown scalar field with a subset of agents having gradient information. As…

Optimization and Control · Mathematics 2023-05-30 Adwait Datar , Christian Hespe , Herbert Werner

Using simulations, we construct the effective dynamics in metabasin space for a Lennard-Jones glass-former. Metabasins are identified via a scheme that measures transition rates between inherent structures, and generates clusters of…

Soft Condensed Matter · Physics 2013-05-29 Yasheng Yang , Bulbul Chakraborty

We study the connection between Lagrangian and Hamiltonian descriptions of closed/open dynamics, for a collection of particles with quadratic interaction (closed system) and a sub-collection of particles with linear damping (open system).…

Classical Physics · Physics 2018-09-18 Farhang Haddad Farshi , Fernando Jiménez , Sina Ober-Blöbaum

The efficiency of an encounter-controlled two-channel reaction between two independently-mobile reactants on a lattice is characterized by the mean number $\rt$ of steps to reaction. The two reactants are distinguished by their mass with…

Statistical Mechanics · Physics 2009-11-11 E. Abad , J. J. Kozak

Lagrangian transport structures for three-dimensional and time-dependent fluid flows are of great interest in numerous applications, particularly for geophysical or oceanic flows. In such flows, chaotic transport and mixing can play…

Fluid Dynamics · Physics 2014-05-09 Rodolphe Chabreyrie , Stefan G. Llewellyn Smith

We study a two-component reaction-diffusion system in which one of the reaction terms becomes singularly large. Assuming that the initial data are nonnegative and mutually segregated, we prove that the solution converges to that of the heat…

Analysis of PDEs · Mathematics 2025-06-12 Yuki Tsukamoto

Multistep catalytic reactions use two different catalysts for the $A\to B$ and the subsequent $B\to C$ reaction, respectively. Often the employed catalysts are chemically incompatible, such as acid-base systems, which prohibits simple…

Computational Physics · Physics 2021-09-10 Gabriel Sitaru , Stephan Gekle

Mixing timescales and residence times in reactive multiphase flows can be essential for product selectivity. For instance when a gas species is consumed e.g. by a competitive consecutive reaction with moderate reaction kinetics where…

Traditional chemical kinetics may be inappropriate to describe chemical reactions in micro-domains involving only a small number of substrate and reactant molecules. Starting with the stochastic dynamics of the molecules, we derive a…

Mathematical Physics · Physics 2009-11-10 D. Holcman , Z. Schuss

Inertial particles in turbulent flows are characterised by preferential concentration and segregation and, at sufficient mass loading, dense particle clusters may spontaneously arise due to momentum coupling between the phases. These…

Fluid Dynamics · Physics 2019-01-30 Alessio Innocenti , Rodney O Fox , Sergio Chibbaro

The role of dimensionality (Euclidean versus fractal), spatial extent, boundary effects and system topology on the efficiency of diffusion-reaction processes involving two simultaneously-diffusing reactants is analyzed. We present…

Statistical Mechanics · Physics 2009-11-10 Jonathan L. Bentz , John J. Kozak , E. Abad , G. Nicolis

In transportation systems (e.g. highways, railways, airports), traffic flows with distinct origin-destination pairs usually share common facilities and interact extensively. Such interaction is typically stochastic due to natural…

Optimization and Control · Mathematics 2019-08-06 Li Jin , Yining Wen

In the framework of the problem of finding proper reaction coordinates (RCs) for complex systems and their effective evolution equations, we consider the case study of a polymer chain in an external double-well potential, experiencing…

Statistical Mechanics · Physics 2020-01-29 Marco Baldovin , Fabio Cecconi , Angelo Vulpiani

Transition to turbulence dramatically alters the properties of fluid flows. In most canonical shear flows, the laminar flow is linearly stable and a finite-amplitude perturbation is necessary to trigger transition. Controlling transition to…

Fluid Dynamics · Physics 2020-05-20 Anton Pershin , Cedric Beaume , Steven M. Tobias

We consider a distributed Lagrange multiplier formulation for fluid-structure interaction problems in the spirit of the fictitious domain approach. This is an unfitted method, which does not require the construction of meshes conforming to…

Numerical Analysis · Mathematics 2026-02-10 Daniele Boffi , Fabio Credali , Lucia Gastaldi