English
Related papers

Related papers: An optimal scale separation for a dynamo experimen…

200 papers

We quantify possible differences between turbulent dynamo action in the Sun and the dynamo action studied in idealized simulations. For this purpose we compare Fourier-space shell-to-shell energy transfer rates of three incrementally more…

Solar and Stellar Astrophysics · Physics 2011-07-08 R. Moll , J. Pietarila Graham , J. Pratt , R. H. Cameron , W. -C. Müller , M. Schüssler

Recent Sunrise/IMaX observations have revealed the existence of supersonic magnetic flows. Our aim is to determine the origin of such flows by using realistic MHD simulations. We simulate cancellation and emergence of magnetic flux through…

Solar and Stellar Astrophysics · Physics 2015-06-22 S. Danilovic , R. H. Cameron , S. K. Solanki

The role of turbulence in current generation and self-excitation of magnetic fields has been studied in the geometry of a mechanically driven, spherical dynamo experiment, using a three dimensional numerical computation. A simple impeller…

Plasma Physics · Physics 2009-11-11 R. A. Bayliss , C. B. Forest , M. D. Nornberg , E. J. Spence , P. W. Terry

The Sun provides an excellent natural laboratory for nonlinear phenomena. We use motions of magnetic bright points on the solar surface, at the smallest scales yet observed, to study the small scale dynamics of the photospheric plasma. The…

Astrophysics · Physics 2009-11-06 J. K. Lawrence , A. C. Cadavid , A. Ruzmaikin , T. E. Berger

In this paper, the physics of flow instability and turbulent transition in shear flows is studied by analyzing the energy variation of fluid particles under the interaction of base flow with a disturbance. For the first time, a model…

Fluid Dynamics · Physics 2018-06-20 Hua-Shu Dou

Regions of quiet Sun generally exhibit a complex distribution of small-scale magnetic field structures, which interact with the near-surface turbulent convective motions. Furthermore, it is probable that some of these magnetic fields are…

Solar and Stellar Astrophysics · Physics 2015-06-18 Paul J. Bushby , Benjamin Favier

At small but supercritical Rayleigh numbers, simulations of dynamos in spherical shells often separate into two broad regimes characterised either by their relative magnetic field strength (weak/strong) or by their dominant force balance…

Fluid Dynamics · Physics 2026-03-18 Luke J. Gostelow , Robert J. Teed

Dynamos driven by rotating convection in the plane layer geometry are investigated numerically for a range of Ekman number ($E$), magnetic Prandtl number ($Pm$) and Rayleigh number ($Ra$). The primary purpose of the investigation is to…

Fluid Dynamics · Physics 2022-11-23 Ming Yan , Michael A. Calkins

The kinematic dynamo (KD) describes the growth of magnetic fields generated by the flow of a conducting medium in the limit of vanishing backaction of the fields onto the flow. The KD is therefore an important model system for understanding…

Astrophysics of Galaxies · Physics 2016-04-27 Igor V. Ovchinnikov , Torsten Enßlin

Optimization of power loss in soft magnetic components basis on the choice of the best technological parameters values. Therefore, the power losses have been measured in Somaloy 500 samples for a wide range of frequency and magnetic…

Materials Science · Physics 2013-04-24 Barbara Slusarek , Bartosz Jankowski , Krzysztof Sokalski , Jan Szczyglowski

A plasma rotating spoke in a crossed field discharge is studied using 2D radial-azimuthal fully kinetic Particle-In-Cell Monte Carlo Collision (PIC/MCC) simulations. The kinetic model reveals the whole perturbation spectrum of the gradient…

Plasma Physics · Physics 2021-08-11 Liang Xu , Denis Eremin , Ralf Peter Brinkmann

Conserved quantities are obtained and analyzed in the new models with global scale invariance recently proposed. Such models allow for non tivial scalar field potentials and masses for particles, so that the scale symmetry must be broken…

General Relativity and Quantum Cosmology · Physics 2009-10-31 E. I. Guendelman

Spontaneous breaking of quantum scale invariance may provide a solution to the hierarchy and cosmological constant problems. In a scale-invariant regularization, we compute the two-loop potential of a higgs-like scalar $\phi$ in theories in…

High Energy Physics - Theory · Physics 2016-12-21 D. M. Ghilencea , Z. Lalak , P. Olszewski

Although the interplanetary magnetic field variability has been extensively investigated in situ by means of data coming from several space missions, the newly launched missions providing high-resolution measures and approaching the Sun,…

Magnetic fields on small scales are ubiquitous in the universe. Though they can often be observed in detail, their generation mechanisms are not fully understood. One possibility is the so-called small-scale dynamo (SSD). Prevailing…

Solar and Stellar Astrophysics · Physics 2023-06-08 Jörn Warnecke , Maarit J. Korpi-Lagg , Frederick A. Gent , Matthias Rheinhardt

A magnetic dynamo experiment is under construction at the New Mexico Institute of Mining and Technology. The experiment is designed to demonstrate in the laboratory the alpha-omega magnetic dynamo, which is believed to operate in many…

Astrophysics · Physics 2009-09-25 S. A. Colgate , V. I. Pariev , H. F. Beckley , R. Ferrel , V. D. Romero , J. C. Weatherall

Hydraulic jumps are oftentimes encountered in natural and human-made environments. The transition from supercritical to subcritical flow involves large energy dissipation rates and substantial air entrainment, preventing the use of…

Fluid Dynamics · Physics 2022-04-26 Matthias Kramer , Daniel Valero

Previous work has introduced scale-split energy density \psi for a given vector field B in order to quantify the field stochasticity S(t). Application to turbulent magnetic fields leads to the prediction that tangling magnetic field by…

High Energy Astrophysical Phenomena · Physics 2020-02-26 Amir Jafari , Ethan Vishniac , Vignesh Vaikundaraman

Natural dynamos such as planets and stars generate global scale magnetic field despite the inferred presence of small scale turbulence. Such systems are known as large scale dynamos and are typically driven by convection and influenced by…

Fluid Dynamics · Physics 2022-02-24 Ming Yan , Michael A. Calkins

In this paper, we study higher-order-accurate-in-time minimizing movements schemes for Wasserstein gradient flows. We introduce a novel accelerated second-order scheme, leveraging the differential structure of the Wasserstein space in both…

Analysis of PDEs · Mathematics 2025-12-23 Raymond Chu , Matt Jacobs