Concept
Linearization
Related publications (106)
Critical degeneracy in a nonlinear hyperbolic equation can produce atypical instability
This paper deals with the initial value problem for a semilinear wave equation on a bounded domain and solutions are required to vanish on the boundary of this domain. The essential feature of the situation considered here is that the ellipticity of the sp ...
2024Stability: a search for structure
In this thesis we study stability from several viewpoints. After covering the practical importance, the rich history and the ever-growing list of manifestations of stability, we study the following. (i) (Statistical identification of stable dynamical syste ...
EPFL2024Self-sustained dynamics and forced resonant oscillations in flows: cross-junction jets and sloshing liquids
In engineering, oscillatory instabilities and resonances are often considered undesirable flow features and measures are taken to avoid them. This may include avoiding certain parametric regions or implementing control and mitigation strategies. However, t ...
EPFL2023Liquid film instability of an internally coated horizontal tube
François Gallaire, Edouard Boujo, Yves-Marie François Ducimetière, Shahab Eghbali
We study numerically and theoretically the gravity-driven flow of a viscous liquid film coating the inner side of a horizontal cylindrical tube and surrounding a shear-free dynamically inert gaseous core. The liquid-gas interface is prone to the Rayleigh-P ...
AMER PHYSICAL SOC2023Gyrokinetic simulation of short wavelength ion temperature gradient instabilities in the ADITYA-U tokamak
Laurent Villard, Emmanuel Lanti
In this work, linear and nonlinear collisionless electrostatic simulation studies of the standard and short wavelength ion temperature gradient mode (SWITG) for experimental profiles and parameters of ADITYA-U tokamak are performed using the linear global ...
IOP Publishing Ltd2023Exploration of the parameter space for the excitation and saturation of Edge Harmonic Oscillations
This thesis presents advancements in the understanding of the plasma conditions leading to the excitation and saturation of the Edge Harmonic Oscillations (EHOs) observed during QH-mode operation in tokamak plasmas. Such operations represent a safer altern ...
EPFL2023Numerical and experimental investigation of spiral-grooved gas journal bearings
Small-scale turbomachinery is increasingly used in carbon-free energy conversion systems, such as commercial or domestic scale heat pumps, fuels cells for transportation and waste heat recovery. The usage of aerodynamic bearings allows the design of compac ...
EPFL2022Non-Linear Behaviors In The Dynamics Of Complex Systems Through A Multifractal Hydrodynamic Model
Some non-linear behaviors in the dynamics of complex systems using the Scale Relativity Theory in the form of Multifractal Hydrodynamic Model are analyzed. By assimilating any complex system to a mathematical multifractal-type object, it is shown that the ...
UNIV POLITEHNICA BUCHAREST, SCI BULL2022Microscopic field theory for structure formation in systems of self-propelled particles with generic torques
Ignacio Pagonabarraga Mora, Elena Sesé Sansa
We derive a dynamical field theory for self-propelled particles subjected to generic torques and forces by explicitly coarse-graining their microscopic dynamics, described by a many-body Fokker-Planck equation. The model includes both intrinsic torques ind ...
AIP Publishing2022Explaining multiple patches of aquatic vegetation through linear stability analysis
Aquatic vegetation is ubiquitous in lowland rivers, and it is typically present in the shape of spatial self-organized patches of biomass. In this work, we mathematically define the threshold conditions for the incipient formation of self-organized vegetat ...
2022