English
Related papers

Related papers: A shape optimization problem for nematic and chole…

200 papers

We consider a variational problem related to the shape of charged liquid drops at equilibrium. We show that this problem never admits global minimizers with respect to $L^1$ perturbations preserving the volume. This leads us to study it in…

Analysis of PDEs · Mathematics 2014-07-17 Michael Goldman , Matteo Novaga , Berardo Ruffini

We study the equilibrium shape of liquid drops minimizing the fractional perimeter under the action of a potential energy. We prove, with a quantitative estimate, that the small volume minimizers are convex and uniformly close to a ball.

Analysis of PDEs · Mathematics 2023-04-14 Konstantinos Bessas , Matteo Novaga , Fumihiko Onoue

Unit-vector fields $\nvec$ on a convex polyhedron $P$ subject to tangent boundary conditions provide a simple model of nematic liquid crystals in prototype bistable displays. The equilibrium and metastable configurations correspond to…

Mathematical Physics · Physics 2009-05-12 A Majumdar , JM Robbins , M Zyskin

Equilibrium shapes of two-dimensional charged, perfectly conducting liquid drops are governed by a geometric variational problem that involves a perimeter term modeling line tension and a capacitary term modeling Coulombic repulsion. Here…

Analysis of PDEs · Mathematics 2019-05-14 Cyrill B. Muratov , Matteo Novaga , Berardo Ruffini

We investigate a fixed domain approach in shape optimization, using a regularization of the Heaviside function both in the cost functional and in the state system. We consider the compliance minimization problem in linear elasticity, a well…

Optimization and Control · Mathematics 2020-04-07 Cornel Marius Murea , Dan Tiba

The Pompeiu problem is considered as shape optimization problem. We show stability of the ball which is the minimum point of related domain functional. The proof is based on shape derivative method. Stability of the ball for general domain…

Optimization and Control · Mathematics 2007-05-23 Arunas Grigelionis

We study the problem of a cholesteric liquid crystal confined to an elliptical channel. The system is geometrically frustrated because the cholesteric prefers to adopt a uniform rate of twist deformation, but the elliptical domain precludes…

Soft Condensed Matter · Physics 2017-06-15 David B. Emerson , Patrick E. Farrell , James H. Adler , Scott P. MacLachlan , Timothy J. Atherton

In this paper we consider a shape optimization problem in which the data in the cost functional and in the state equation may change sign, and so no monotonicity assumption is satisfied. Nevertheless, we are able to prove that an optimal…

Analysis of PDEs · Mathematics 2017-04-24 Giuseppe Buttazzo , Bozhidar Velichkov

We model within the framework of finite elasticity two inherent instabilities observed in liquid crystal elastomers under uniaxial tension. First is necking which occurs when a material sample suddenly elongates more in a small region where…

Soft Condensed Matter · Physics 2024-10-15 Rabin Poudel , Yasemin Sengul , L. Angela Mihai

We consider shape optimization problems with internal inclusion constraints, of the form $$\min\big\{J(\Omega)\ :\ \Dr\subset\Omega\subset\R^d,\ |\Omega|=m\big\},$$ where the set $\Dr$ is fixed, possibly unbounded, and $J$ depends on…

Analysis of PDEs · Mathematics 2011-09-13 Dorin Bucur , Giuseppe Buttazzo , Bozhidar Velichkov

In general, standard necessary optimality conditions cannot be formulated in a straightforward manner for semi-smooth shape optimization problems. In this paper, we consider shape optimization problems constrained by variational…

Optimization and Control · Mathematics 2020-12-17 Daniel Luft , Volker H. Schulz , Kathrin Welker

Using computer simulations we investigate the microscopic structure of the singular director field within a nematic droplet. As a theoretical model for nematic liquid crystals we take hard spherocylinders. To induce an overall topological…

Soft Condensed Matter · Physics 2009-10-31 J. Dzubiella , M. Schmidt , H. Loewen

We present a general numerical approach to shape optimization with state constraints for 2-dimensional geometries, without relaxing the constraints. To do this we reformulate the problem on a fixed reference domain using a conformal…

Optimization and Control · Mathematics 2014-12-16 Christian Leithäuser , René Pinnau , Robert Feßler

We numerically study the dynamics of quasi-two dimensional cholesteric liquid crystal droplets in the presence of a time-dependent electric field, rotating at constant angular velocity. A surfactant sitting at droplet interface is also…

Soft Condensed Matter · Physics 2023-03-13 F. Fadda , A. Lamura , A. Tiribocchi

In this paper we analyze a shape optimization problem, with Stokes equations as the state problem, defined on a domain with a part of the boundary that is described as the graph of the control function. The state problem formulation is…

Numerical Analysis · Mathematics 2014-03-17 Ivan Fumagalli , Nicola Parolini , Marco Verani

This article analyzes modulated phases in liquid crystals, from the long-established cholesteric and blue phases to the recently discovered twist-bend, splay-bend, and splay nematic phases, as well as the twist-grain-boundary (TGB) and…

Soft Condensed Matter · Physics 2025-07-08 Jonathan V. Selinger

We consider the problem of finding optimal shapes of fluid domains. The fluid obeys the Navier--Stokes equations. Inside a holdall container we use a phase field approach using diffuse interfaces to describe the domain of free flow. We…

Optimization and Control · Mathematics 2014-05-15 Harald Garcke , Claudia Hecht , Michael Hinze , Christian Kahle

We derive a F\"{o}ppl-von K\'{a}rm\'{a}n-type constitutive model for solid liquid crystalline plates where the nematic director may or may not rotate freely relative to the elastic network. To obtain the reduced two-dimensional model, we…

Soft Condensed Matter · Physics 2020-07-30 L. Angela Mihai , Alain Goriely

We study the growth of aligned domains in nematic liquid crystals. Results are obtained solving the Beris-Edwards equations of motion using the lattice Boltzmann approach. Spatial anisotropy in the domain growth is shown to be a consequence…

Soft Condensed Matter · Physics 2007-05-23 Geza Toth , Colin Denniston , J. M. Yeomans

We consider a shape optimization problem written in the optimal control form: the governing operator is the $p$-Laplacian in the Euclidean space $\R^d$, the cost is of an integral type, and the control variable is the domain of the state…

Optimization and Control · Mathematics 2021-06-28 Giuseppe Buttazzo , Francesco Paolo Maiale , Bozhidar Velichkov