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The use of microgrids is a relevant direction of energy development both in Russia and abroad. At the same time, problems arise in selecting an optimal structure and operating parameters of such networks. Conducting full-scale experiments with a real energy complex involves certain risks associated with high time and financial costs, as well as the reliability and safety of its equipment. Therefore, studies are usually carried out on mathematical or physical models of a microgrid. A physical model allows solving a number of important problems. These include the analysis of the network structure, the study of its main characteristics (resilience, reliability, regulation of demand and supply of energy resources, use of renewable energy sources, and other features) and the determination of optimal operating modes. The paper considers a monitoring system for a physical model of a microgrid (a simulation stand that simulates a network with a high share of renewable energy sources).

A method and technical instrumentation are proposed for estimating the sizes of vortex structures generated in the annular gap of a Couette - Taylor system. The size estimation of these structures is based on analyzing the measured amplitude-frequency spectra of radial dynamic pressure pulsations. A simplified model of vortex generation in the Couette - Taylor annular flow, driven by the rotation of the inner cylinder surface, is introduced. Using this model and the measured amplitude-frequency spectra of radial pressure pulsations, the sizes of the generated vortices in the Couette - Taylor flow are evaluated. The results reveal three distinct types of vortices: vortices with diameters significantly smaller than the annular gap width, vortices with diameters comparable to the gap width, and vortices with diameters substantially exceeding the gap width, leading to their deformation (flattening).

The paper presents a gradient boosting-based machine learning model developed to predict the occurrence of defects (dross) on galvanized steel sheets used in the automotive industry. An analysis of the influence of process parameters on the occurrence of defects is carried out, which makes it possible to identify the key factors affecting the quality of the coating: coil rolling speed, elongation and force in the coil-scin pass mill, zinc coating at top, temperature in the galvanizing pot, and temperature in the furnace snout. Based on the results of the study, a digital assistant is developed for evaluating coils in real time, providing simulation of the decision-making process and helping in prompt managing of the technological process.

The article presents modifications to the Sardana software package for automating synchrotron radiation experimental stations. These modifications are aimed at achieving the nominal accuracy of positioners, reducing the time consumption with the minimum operator supervision. In addition, these modifications simplify conducting standard experiments and provide greater flexibility in configuring experimental setups. They are applied to the automated control system of the sample environment at Experimental Station 1-1 "Microfocus."

The article problem of optimal performance for a process described by a system of nonlinear differential equations is considered. To determine an approximate solution to the problem, it is proposed to apply the evolutionary method of artificial immune systems, which offers an advantage of the lack of sensitivity to the choice of the initial approximation. To find a numerical solution to the problem of optimal performance, a step-by-step algorithm is formulated, whose operation is tested on a model problem. Suboptimal control in terms of response time is obtained, and the algorithm parameters are determined that allow one to calculate the problem solution with the least computational costs. The efficiency of the developed algorithm is demonstrated by comparing the results of numerical calculations with the results of applying the fixed-point method.

This paper presents generalized results of numerical analysis of the effect of mesoscopic thermal dissipation and heat transfer processes on the temperature field formed in a shock-compressed viscoplastic porous material containing spherical pores with a thin layer of plasticizer on the surface of pores in plastic flow. Based on the results, a theoretical estimate is made of the effect of the mechanical properties of the phases on the critical conditions of shock-wave initiation of chemical reaction in the two-phase porous energetic material.

The investigation of the energy output resulting from alterations in the aluminum powder content in emulsion explosives permits the expeditious transformation of civilian explosives into military explosives during wartime, while simultaneously enhancing the energy capacity of the equipment. One can choose the appropriate scenario based on the form and energy yield of the explosives. The experiments were conducted using emulsion explosives with 0%, 5%, 10%, 20%, 30% and 40% mass percentage of aluminum powder. The study investigates the effects of varying aluminum powder contents on detonation velocity, brisance, underwater explosions, and aerial explosions. The experimental outcomes show that the detonation speed decreases with increasing aluminum powder content. The brisance of the emulsion explosive initially ascends and subsequently descends, reaching its pinnacle value of 22.71 mm at an aluminum powder content of 20%, reflecting a surge of 19.97%. As the aluminum powder content increases, all underwater explosion parameters of the emulsion explosive increase linearly, with the total energy reaching its maximum at 40%, showing increases of 120% compared to the aluminum-free emulsion explosive. The highest pressure increase in aerial explosions is achieved at an aluminum powder content of 30%, reaching 113.28 kPa and signifying a 78% rise. The experimental findings demonstrate that in the context of underwater munitions employing high-energy emulsified explosives, including 40% aluminum powder results in the optimal level of destructive capability. Conversely, when considering applications for aerial weaponry, the maximum explosive potential is attained with an aluminum powder content of 30%.

A wide-range semiempirical equation of state of liquid and gaseous neon is constructed with account for evaporation and thermal ionization based on a modified van der Waals model for mixed substances. The model and the simplifications used in this study are described. The values of the key parameters are given. The results of model calculations are compared with experimental data up to a pressure of ≈1 000 GPa and with the results of calculations based on other models, including those at a pressure of >1 000 GPa. In the low-density limit, the model transforms into an equation of state of a mixture of ideal gases of atoms, ions of all multiplicities, and electrons with a concentration determined by the Saha equations.

Experiments on measuring the electrical resistance of copper foil under shock compression are analyzed for determining the basic parameters responsible for the concentration of shock-induced defects in the metal. Based on the excessive electrical conductivity of the metal, the concentration of point defects of the crystal structure in copper samples placed in various cartridges (Plexiglas, micarta, and fluoroplastic) is estimated. The cartridge material is found to affect the number of defects arising due to shock compression of the metal. The cartridge with a higher shock impedance corresponds to a smaller concentration of defects in the sample (at identical pressures of the shock wave in the cartridge). A physical model of generation of crystal structure defects due to shock compression is formulated to explain the experimental results obtained. According to this model, defects are formed during matter compression in the shock wave front and remain “frozen” after unloading. A new portion of defects is formed after secondary compression of matter, resulting in accumulation of defects. It is assumed that the parameter determining the number of defects arising under dynamic loading is the algebraic sum of metal deformations at each stage of shock compression. The data presented in the variables concentration of defects - deformation yield a dependence that mitigates the difference in the cartridge material. The analysis performed shows that the sum of deformations can be considered as a parameter determining the concentration of defects generated by shock compression of copper.

The expansion and rupture of metal casing under internal explosion loads may form a large number of fragments. An understanding of how the relevant parameters of metal casing influence the fragment mass distribution, is essential for the prediction of the power of metal casing explosive devices and the effective design of protection systems. In this paper, the important influence factors of metal casing (mechanical properties of casing material, geometric structure of casing, performance of explosive) were determined by a dimensional analysis. Several complete recycle tests of fragment were carried out to analyze the influence of these relevant parameters on the natural fragment mass distribution. Based on the test results, it is found that these relevant parameters have a linear relationship with the distribution modulus of the fractal model of natural fragment mass distribution in double-logarithmic coordinates. A formula was developed to predict the distribution modulus, whose influence parameters were considered in a dimensionless way. The applicability of the estimating method was verified with the test data of a casing with irregular axial geometry. The error between the calculation result and test result was only 6.9%. In addition, the test data compared with the prediction results of two theories, and the fractal model of natural fragment mass distribution showed better accuracy. This work can provide a reference for the hazard assessment and protection system design of metal casing explosive devices.