The JOREK extended magneto-hydrodynamic (MHD) code is a widely used simulation for studying the non-linear dynamics of large-scale instabilities in divertor tokamak plasmas. Due to large scale-separation intrinsic these phenomena both space and time, computational costs simulations realistic geometry with parameters can be very high, motivating investment considerable effort optimization. In th...

A new method to detect finite-time blow-up in systems of ordinary differential equations is presented. This simple algorithmic procedure is based on the analysis of singularities in complex time and amounts to checking the real-valuedness of the leading order term in the asymptotic series describing the behavior of the general solution around movable singularities. Illustrative examples and an ...

A complete analytical and numerical treatment of all magnetohydrodynamic waves and instabilities for radially stratified, magnetized accretion disks is presented. The instabilities are a possible source of anomalous transport. While recovering results on known hydrodynamic and both weak-and strong-field mag-netohydrodynamic perturbations, the full magnetohydrodynamic spectra for a realistic acc...

The ”reverse–dynamo” mechanism — the amplification/generation of fast plasma flows by micro scale (turbulent) magnetic fields via magneto–fluid coupling is recognized and explored. It is shown that macroscopic magnetic fields and flows are generated simultaneously and proportionately from microscopic fields and flows. The stronger the micro–scale driver, the stronger are the macro–scale product...

Recent experiments have shown that it is possible to study a fundamental astrophysical process such as dynamo action in controlled laboratory conditions using simple MHD flows. In this paper we explore the possibility that Taylor-Couette flow, already proposed as a model of the magneto-rotational instability of accretion discs, can sustain generation of magnetic field. Firstly, by solving the k...

We investigate new solutions for magnetized neutron stars with a barotropic core in magnetohydrodynamic (MHD) equilibrium and magneto-elastic crust, which was neglected by previous studies concerning MHD equilibrium. The Lorentz force of the star is purely irrotational structures magnetic fields are constrained. By contrast, solenoidal component exists elastic crust less restricted. find that m...

Dynamo activity caused by waves in a rotating magneto-plasma is investigated. In astrophysical environments such as accretion disks and at sufficiently small spatial scales, the Hall effect is likely to play an important role. It is shown that a combination of the Coriolis force and Hall effect can produce a finite α-effect by generating net helicity in the small scales. The shear/ion-cyclotron...

In samples used to maintain the US resistance standard the breakdown of the dissipationless integer quantum Hall effect occurs as a series of dissipative voltage steps. A mechanism for this type of breakdown is proposed, based on the generation of magneto-excitons when the quantum Hall fluid flows past an ionised impurity above a critical velocity. The calculated generation rate gives a voltage...

ω(t, x) ∈ Rand b(t, x) ∈ R, and p(t, x) ∈ R denote, respectively, the microrotational velocity, the magnetic field, and the hydrostatic pressure. μ, χ, κ, γ, and ] are positive numbers associated with properties of the material: μ is the kinematic viscosity, χ is the vortex viscosity, κ and γ are spin viscosities, and 1/] is the magnetic Reynold. u 0 , ω 0 , and b 0 are initial data for the vel...