ISSN 0869-6632 (Print)
ISSN 2542-1905 (Online)

numerical modeling

Nonstationary discrete theory of excitation of periodic structures and its application for simulation of traveling-wave tubes

Aim. This article presents a review of the nonstationary (time-domain) discrete theory of excitation of periodic electromagnetic structures and discusses applications of the theory for simulation of traveling-wave tube (TWT) microwave power amplifiers with slow-wave structures (SWS) of different kind. Methods. The discrete theory is based on a representation of a periodic SWS as a chain of coupled cells.

Oscillatory media properties influence on excitation propagation

We study synchronization in ensembles of locally diffusive coupled Bonhoeffer–van der Pol oscillators. Individual elements frequencies influence on excitation propagation in one- and two-dimensional media is investigated. We show that excitation propagation speed depends on frequency mismatch between synchronization frequency and elements’ individual frequencies. Qualitative and quantitative results describing this effect are numerical modeling data and analytical research.

Investigation of particularities formation spatially periodic structures of multieddy isothermal electroconvection

Electroconvective flow in plane horizontal layer of dielectric liquid due to the crisis of the equilibrium layer stability loss in homogeneous electric field are numerically modeled.

Method for calculation of lyapunov exponents spectrum from data series

The new method for the calculating of the spectrum of the Lyapunov exponents from data series is proposed. The already known methods of the same thematic are investigated. The Roessler system is given as an example for describing the proposed method. The results of numerical modeling are presented.

Nonlinear dynamics of helical electron flow in the regime of the virtual cathode forming

We produce the results of computer analysis of complex dynamics of non-relativistic electron beam being placed in crossed electric and magnetic fields, in the regime of a virtual cathod forming in additional braking field. The modeling has been made in the framework of 2D numerical model in the geometry of magnetron-injector gun.

Study of synchronization in the system of two delay-coupled gyrotrons using a modified quasilinear model

Topic. The paper is devoted to the study of mutual synchronization of two gyrotrons coupled with delay. As a rule, a theoretical study of synchronization of gyrotrons and other microwave oscillators is usually carried out by numerical simulations using certain well-established models of microwave electronics. Using this approach, it is difficult to provide a fairly complete synchronization pattern, using methods and ideas of nonlinear dynamics. Aim.