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Single and double curl Beltrami magnetic fields are studied numerically in connection with their transport properties, and the results are compared and analyzed by characterizing the magnetic field lines. In the phase space of the single curl Beltrami field, islands of regular field lines are embedded into the chaotic sea, whereas the field lines for certain solutions of the double curl Beltrami field are chaotic over the entire space. Due to the presence of regular islands in phase space, the chaotic trajectories show stickiness phenomena which are characterized by the distribution of a chaotic field line. The dynamical traps in chaotic orbits due to stickiness phenomena are also characterized by the distribution of finite distance Lyapunov exponents. Finally, the recurrence length distribution of chaotic trajectories is plotted to understand their global behaviour.

The performed magnetohydrodynamic simulations aim to assess the influence of chaotic magnetic field lines on spontaneous generation of current sheets in an evolving viscous magnetofluid with infinite electrical conductivity. Suitable non-force-free initial fields having chaotic magnetic field lines are constructed by superposing two Arnold-Beltrami-Childress magnetic fields. The construction is such that the superposed field is devoid of any three or two-dimensional magnetic nulls, which are potential sites of current sheet development. Consequently, the notion of spontaneity can be attributed to any current sheet generated by the evolving magnetofluid. Moreover, to ensure the development to be spontaneous, the simulations are performed in congruence with Parker's magnetostatic theorem which necessitates an attainment of a terminal quasi-steady state and maintenance of flux-freezing to high fidelity. Importantly, the paper establishes spontaneous onset of volume distributed current sheets to be positively...

The dynamics of charged particles is studied in stationary magnetic fields that are obtained as solutions of nonlinear coupled equations varying in one dimension. The chosen equation can give both regular and chaotic solutions depending on the chosen coupling parameter. For chaotic numerical solution of the equation, rms values of fluctuation are increased by changing the coupling parameter, whereas for regular analytical solution, rms values of fluctuation are increased by changing the amplitude of fluctuation. Energy gain of an ensemble of particles is studied in both cases in the presence of a uniform electric field. Ensemble averaged energy gain is shown to decrease with the increase in rms values of fluctuation in the first case and increase with the increase in rms values of fluctuation in the second case.