Context. The MHD instabilities can generate complex field topologies even if the initial field configuration is a very simple one. Aims. We consider the stability properties of magnetic configurations containing a toroidal and an axial field. In this paper, we concentrate mainly on the behavior of non-axisymmetric perturbations in axisymmetric magnetic configurations. Methods. The stability is ...

In this paper, a semi-analytical solution for magneto-thermo-elastic problem in an axisymmetric functionally graded (FG) hollow rotating disk with constant thickness placed in uniform magnetic and thermal fields with heat convection from disk’s surfaces is presented. Solution for stresses and perturbation of magnetic field vector in a thin FG rotating disk is determined using infinitesimal theo...

A study of the three-dimensional axisymmetry-breaking instability of an axisymmetric convective #ow associated with crystal growth from bulk of melt is presented. Convection in a vertical cylinder with a parabolic temperature pro"le on the sidewall is considered as a representative model. The main objective is the calculation of critical parameters corresponding to a transition from the steady ...

In the present paper, an axisymmetric two-dimensional model for powder mixed electric discharge machining (PMEDM) has been developed using the finite element method (FEM). The model utilizes the several important aspects such as temperaturesensitive material properties, shape and size of heat source (Gaussian heat distribution), percentage distribution of heat among tool, workpiece and dielectr...

A transport barrier which is characterized by the steeper temperature or/and density gradient has been observed both in the core region (internal transport barrier : ITB) and edge region (edge transport barrier : ETB) in the plasmas with non-axisymmetric magnetic fields compared with the gyro-Bohm type L-mode transport. A reduction of thermal conductivity and particle diffusivity in these plasm...

Observations show that solar activity is distributed non-axisymmetrically, concentrating at “preferred longitudes”. This indicates the important role of non-axisymmetric magnetic fields in the origin of solar activity. We investigate the generation of the non-axisymmetric fields and their coupling with axisymmetric solar magnetic field. Our kinematic generation (dynamo) model operating in a sph...

Increasing observations are becoming available about a relatively weak, but persistent, non-axisymmetric magnetic field co-existing with the dominant axisymmetric field on the Sun. It indicates that the non-axisymmetric magnetic field plays an important role in the origin of solar activity. A linear non-axisymmetric α − Ω dynamo model is set up to discuss the characteristics of the axisymmetric...

A heavy ion beam probe (HIBP) is a unique diagnostic method to measure the electric potential in magnetically confined high temperature plasmas. Its fine probing beam and well-collimated secondary beam detector give this diagnostic good spatial resolution, which together with the good time resolution make it powerful in probing plasma interior both in steady state and transient state. There are...