Vol 64, No 6 (2019)

The results from evaluating the economic feasibility of ownership of photovoltaic (PV) microgeneration systems with reference to the consumed energy cost criterion are presented. The evaluation is carried out based on the results of modeling and simulation of three photovoltaic system (PVS) configurations: without energy storing, with electric energy storage, and with thermal energy storage under the conditions of a few prospective regions of Russia taking into account the emerging regulatory norms and mechanisms supporting the development of microgeneration. It is shown that under certain conditions PV microgeneration systems can be competitive in a number of energy isolated regions and in certain non-pricing zones of the wholesale electricity and capacity market, in particular, on the territory of the Republic of Sakha (Yakutia), whereas in pricing zones PV microgeneration is economically unfeasible for any of the system configurations considered.

A method for the structural characterization of 2D-nanofiller tactoids in the polymer matrix of a nanocomposite has been proposed to demonstrate that the mentioned tactoids are fractal objects with a dimension of 1.75–2.16. This variation of the structural state of tactoids is due to interfacial interactions. It has been demonstrated within the framework of percolation reinforcement theory that the structure of tactoids is the only factor governing the degree of reinforcement of nanocomposites. The efficiency of a nanocomposite is characterized by its ability to form interfacial regions.

In n-dimensional space (multidimensional continuum), the compatibility equations (\(m \geqslant 1\), \(n \geqslant 2\)) are derived for the components of the generalized strains of rank m associated with the generalized displacements of rank m – 1 by the analogs of the Cauchy kinematic relations. The compatibility conditions may be written in the form of vanishing of all components of the incompatibility tensor of rank \(m(n - 2)\) or of the generalized Riemann–Christoffel tensor of rank 2m, which is dual to it. The number of independent components of these tensors coinciding with the number of compatibility equations in terms of generalized strains is determined.

The results of experimental study of the effect the dielectric barrier discharge (DBR) actuator on the laminar-turbulent transition in a three-dimensional boundary layer under the influence of elevated free-stream turbulence are presented. Traveling cross-flow instability modes dominate in the transition to turbulence in the base boundary layer. Their characteristics are independent of the spanwise position. The DBR actuator that generates stationary longitudinal vortices with a predefined spanwise wavelength when turned on is able to lower the production rate of turbulent spots in comparison with the base regime.