Generation of large-scale magnetic field by Rayleigh-Bénard convection

• Grant number: 13/01242-8
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): August 01, 2013
• Effective date (End): July 31, 2016
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Solar System Astronomy
• Principal researcher: Erico Luiz Rempel
• Grantee: Roman Chertovskikh
• Home Institution: Divisão de Ciências Fundamentais (IEF). Instituto Tecnológico de Aeronáutica (ITA). Ministério da Defesa (Brasil). São José dos Campos , SP, Brazil

Abstract

Magnetic fields of many astrophysical objects are sustained by convection in their interior (e.g., in the solar convective zone or the Earth's molten outer core); this mechanism of magnetic field generation is known as convective dynamo. Many spatial and temporal scales are present in astrophysical magnetic fields. To split large-scale and small-scale dynamics in the convective dynamo problem, asymptotic methods are applied. The object of this study is the large-scale stability analysis of the dynamo sustained by thermal convection in the idealised setup - in a rotating horizontal plane layer ofelectrically conducting fluid, with free electrically conducting boundaries.Evolution of large-scale perturbations of the regimes will be investigated by solving the system of the governing amplitude equations. The amplitude equations constitute a system of partialdifferential equations that reduces in some instances to the system of the mean-field equations. Various phenomena affect large-scale perturbations of convective hydromagnetic (CHM) regimes: kinematic and magnetic alpha-effect, anisotropic combined eddy diffusivity and eddy advection. These effects, governed by amplitude equations for perturbations of a short-scale CHM regime, will also be quantified for a number ofsymmetric CHM attractors that have been simulated by the candidate.

Scientific publications

(6)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CHERTOVSKIH, R.; REMPEL, E. L.; CHIMANSKI, E. V. Magnetic field generation by intermittent convection. Physics Letters A, v. 381, n. 38, p. 3300-3306, OCT 10 2017. Web of Science Citations: 3.

SHAMAROVA, EVELINA; CHERTOVSKIH, ROMAN; RAMOS, ALEXANDRE F.; AGUIAR, PAULO. Backward-stochastic-differential-equation approach to modeling of gene expression. Physical Review E, v. 95, n. 3 MAR 29 2017. Web of Science Citations: 1.

CHIMANSKI, EMANUEL V.; REMPEL, ERICO L.; CHERTOVSKIH, ROMAN. On-off intermittency and spatiotemporal chaos in three-dimensional Rayleigh-Benard convection. Advances in Space Research, v. 57, n. 6, p. 1440-1447, MAR 15 2016. Web of Science Citations: 0.

CHERTOVSKIH, R.; ZHELIGOVSKY, V. Large-scale weakly nonlinear perturbations of convective magnetic dynamos in a rotating layer. PHYSICA D-NONLINEAR PHENOMENA, v. 313, p. 99-116, DEC 1 2015. Web of Science Citations: 3.

CHERTOVSKIH, R.; CHIMANSKI, E. V.; REMPEL, E. L. Route to hyperchaos in Rayleigh-Benard convection. EPL, v. 112, n. 1 OCT 2015. Web of Science Citations: 3.

PODVIGINA, O.; ZHELIGOVSKY, V.; REMPEL, E. L.; CHIAN, A. C. -L.; CHERTOVSKIH, R.; MUNOZ, P. R. Two-parameter bifurcation study of the regularized long-wave equation. Physical Review E, v. 92, n. 3 SEP 14 2015. Web of Science Citations: 0.