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Related papers: DNS of the kappa-mechanism

200 papers

Context: Hydrodynamical model of the kappa-mechanism in a purely radiative case. Aims: First, to determine the physical conditions propitious to kappa-mechanism in a layer with a configurable conductivity hollow and second, to perform the…

Astrophysics · Physics 2009-11-13 T. Gastine , B. Dintrans

Context: We study the kappa-mechanism that excites radial oscillations in Cepheid variables. Aims: We address the mode couplings that manages the nonlinear saturation of the instability in direct numerical simulations (DNS). Methods: We…

Astrophysics · Physics 2009-11-13 T. Gastine , B. Dintrans

A strong coupling between convection and pulsations is known to play a major role in the disappearance of unstable modes close to the red edge of the classical Cepheid instability strip. As mean-field models of time-dependent convection…

Solar and Stellar Astrophysics · Physics 2015-05-14 T. Gastine , B. Dintrans

We investigate the dissipative dynamics of linear and nonlinear waves in harmonic traps by means of engineered complex non-Hermitian potentials. By combining an analytical mapping between real and complex Schr\"odinger equations with direct…

Quantum Physics · Physics 2026-05-14 Mario Salerno

The dynamics of phase-separated interfaces shape the behavior of both passive and active condensates. While surface tension in equilibrium systems minimizes interface length, non-equilibrium fluxes can destabilize flat or constantly curved…

Soft Condensed Matter · Physics 2025-05-27 Florian Raßhofer , Simon Bauer , Alexander Ziepke , Ivan Maryshev , Erwin Frey

The 2D second-mode is a potent instability in hypersonic boundary layers (HBLs). We study its linear and nonlinear evolution, followed by its role in transition and eventual breakdown of the HBL into a fully turbulent state. Linear…

Fluid Dynamics · Physics 2020-12-02 S. Unnikrishnan , Datta V. Gaitonde

We examine the nonlinear development of unstable magnetosonic waves driven by a background radiative flux -- the Radiation-Driven Magneto-Acoustic Instability (RMI, a.k.a. the "photon bubble" instability). The RMI may serve as a persistent…

Solar and Stellar Astrophysics · Physics 2015-06-12 Rodrigo Fernández , Aristotle Socrates

Using linear non-adabatic pulsation analysis, we explore the radial-mode (p-mode) stability of stars across a wide range of mass (0.2 <= M <= 50 Msun), composition (0 <= X <= 0.7, Z=0.001, 0.02), effective temperature (3 000 <= T_eff <= 40…

Solar and Stellar Astrophysics · Physics 2016-03-09 C. S. Jeffery , H. Saio

Non-equilibrium (NE) molecular dynamics (MD), or NEMD, gives a "direct" simulation of thermal conductivity kappa. Heat H(x) is added and subtracted in equal amounts at different places x. After steady state is achieved, the temperature T(x)…

Materials Science · Physics 2016-12-06 Philip B. Allen , Yerong Li

The instability of the dust-acoustic waves driven by drifting electrons and ions in a dusty plasma is investigated by the kinetic theory. All the plasma components (electrons, ions and dust particles) are assumed to be the Lorentzian…

Plasma Physics · Physics 2015-08-10 Zhipeng Liu , Jiulin Du

Isotropic turbulence is typically studied numerically through the direct numerical simulations (DNS). The DNS flows are described by the Navier-Stokes equation in a 'box', defined through periodic boundary conditions. The DNS flows live in…

Fluid Dynamics · Physics 2017-08-02 Elias Gravanis , Evangelos Akylas

In the present work, we consider a variety of two-component, one-dimensional states in nonlinear Schrodinger equations in the presence of a parabolic trap, inspired by the atomic physics context of Bose-Einstein condensates. The use of…

Pattern Formation and Solitons · Physics 2017-06-28 Haitao Xu , Panayotis G. Kevrekidis , Todd Kapitula

A semi-analytic model is developed to study the effects of kappa-distributed lighter constituents and the associated kappa-modified polarization force on the classical Jeans instability in dust molecular clouds (DMCs). The constitutive…

Astrophysics of Galaxies · Physics 2025-04-29 Dipankar Ray , Pralay Kumar Karmakar , Siddhartha Saikia

Semiconductor $p^+ - p^- - n - p^+ - n^{++}$ structures with large junction and contact areas are treated as 1 \times 2-dimensional active media, in which self-organized pattern formation can be expected. The local bistable behavior of the…

patt-sol · Physics 2009-10-31 A. V. Gorbatyuk , F. -J. Niedernostheide

The amorphous solids can be theoretically modeled by anharmonic disordered lattices. However, most of theoretical studies on thermal conductivity in anharmonic disordered lattices only focus on the potentials of hard-type (HT)…

Statistical Mechanics · Physics 2023-03-16 Jianjin Wang , Chi Xiong , Daxing Xiong

Attempts to understand the dynamics of warped astrophysical discs have garnered significant attention, largely motivated by the growing catalogue of observed distorted systems. Previous studies have shown that the evolution of the warp is…

Solar and Stellar Astrophysics · Physics 2023-01-25 Callum W. Fairbairn , Gordon I. Ogilvie

A theoretic framework for dynamics is obtained by transferring dynamics from state space to its dual space. As a result, the linear structure where dynamics are analytically decomposed to subcomponents and invariant subspaces decomposition…

Fluid Dynamics · Physics 2020-07-03 Wei Zhang , Mingjun Wei

A new class of semi-implicit numerical schemes for linear advection equation on Cartesian grids is derived that is inspired by so-called $\kappa$-schemes used with fully explicit discretizations for this type of problems. Opposite to fully…

Numerical Analysis · Mathematics 2016-11-15 Peter Frolkovič , Karol Mikula

By means of a modified Lugiato-Lefever equation model, we investigate the nonlinear dynamics of dissipative wave structures in coherently-driven Kerr cavities with a parabolic potential. The potential stabilizes system dynamics, leading to…

We have studied the entropy-driven mechanism leading to stationary patterns formation in stochastic systems with local dynamics and non-Fickian diffusion. We have shown that a multiplicative noise fulfilling a fluctuation-dissipation…

Statistical Mechanics · Physics 2008-06-20 D. O. Kharchenko , S. V. Kokhan , A. V. Dvornichenko
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