Vol 64, No 10 (2019)

By the example of an inhomogeneous electromagnetic wave formed by the superposition of two plane monochromatic electromagnetic waves, which are arbitrarily directed relative to each other, an approach is demonstrated that makes it possible to simulate a broad spectrum of electromagnetic waves. The complete set of equations describing the motion of an electron in an inhomogeneous electromagnetic field is solved numerically. The features of the trajectory and emission spectrum of the electron are found and investigated.

According to experimental results, a comparison of sizes of child droplets after micro-explosion fragmentation of water–Diesel droplets is conducted. Convective, conductive, or radiative heat exchange dominated in each experiment. The temperature of the medium and the relative volume concentration of the flammable liquid are varied in the ranges from 100–450°С and from 10–90 vol %. The ratios of the sizes of the droplets formed to the sizes of the original ones are established. The conditions are shown under which it is possible to increase the total surface area of evaporation of a liquid by tenfold or more using the micro-explosion of droplets.

The problem of modeling the attitude control modes of small spacecraft using electromagnetic systems interacting with the Earth’s magnetic field is considered. A mathematical model for the angular motion dynamics of small spacecraft has been developed. The control law for linear magnetic attitude control systems of small spacecraft is formulated. The results of our numerical modeling of the motion of a satellite with a magnetic attitude control system are presented.

It is proved that, with the same instantaneous distribution of the flow velocity of a viscous incompressible fluid, the forces acting on a body moving with acceleration and the forces acting on the body moving with constant velocity differ in the vector that is equal to the tensor of added masses multiplied by the acceleration vector. The tensor of added masses coincides with the tensor calculated for potential flows with the same geometry of the body and the surrounding surfaces and does not depend either on viscosity or on the distribution of vorticity in the flow space while the force corresponding to the motion with constant velocity depends on the motion prehistory.

Biofuels are an important source of energy that currently cover about 10% of the world’s energy demand, including 2% of electricity generation and 2.5% of liquid fuel consumption. In Russia, wood fuel is among the most available and abundant sources of renewable energy. Possible changes in the energy potential of Russia’s forest resources induced by changes in the atmospheric composition and climate are studied. This article presents estimates of global changes in the CO₂ concentration and the average annual air temperature across the Russian territory for the period up to 2050 obtained using the climatic model and the carbon cycle model developed at the Moscow Power Engineering Institute. The results of our simulations obtained show that the change in the net primary production of Russian forests caused by the growth in the CO₂ content in the atmosphere, the increase of temperature, and the larger amount of precipitation will rinduce an increase of the available wood fuel energy resources by 30% or by more than 9 million tce/year by the middle of the current century.