Vol 23, No 1 (2022)

Evaluation criterion of the neural network model of heterostructural nanoelectronic devices for predicting their electrical parameters

Vetrova N.A., Filyaev A.A.

Abstract

The paper is devoted to the neural network approach, which is proposed to be used to predict the operational parameters of heterostructural nanoscale devices. The advantage of this approach is a clear methodology for evaluating the weighting coefficients as part of a trained artificial neural network, which makes it possible to solve the problem for devices with an arbitrary structure. Learning is a complex iterative process, at the end of which it is important to evaluate the functioning of the neural network model. Therefore, it is necessary to determine the achieved accuracy and to identify negative effects that may occur during the learning process, when such a model is being developed. The project presents a criterion for evaluation the training quality of the neural network model of heterostructural nanoelectronic devices for predicting their electrical parameters. The main advantage of this criterion is its sensitivity to negative effects arising in the learning process, which was demonstrated by an example with two input training parameters and confirmed by visual control of 3D surfaces. The applicability of the developed criterion in the selection of neural networks with arbitrary architecture for solving design problems in the development of semi-conductor devices has been proved.

RUDN Journal of Engineering Research. 2022;23(1):7-14
pages 7-14 views

Inert anode technology in the concept of green aluminum metallurgy

Morozov Y.A., Yalunin V.S.

Abstract

An analysis is made of the traditional and advanced electrolytic technology for producing metallic aluminum from the point of view of environmental friendliness of production. A brief description is given of the use of Soderberg anode cells and pre-baked anodes combined by a common carbon anode material oxidized into gaseous oxide and carbon dioxide during aluminum reduction. In order to reduce (eliminate) the carbon footprint, the concept of an inert anode is proposed, the material of which does not enter into the aluminum reduction reaction, and therefore is not consumed (almost), while the release of oxygen in the status of the final gaseous “waste” is allowed. The basis for the development is an electrolytic cell with a self-baking Soderberg anode of the S-8BM type, which characterizes the oldest technology and has a large geography of representation in Russia. As a result of comparing the operating conditions and technological possibilities for obtaining anodes of similar sizes from composite and ceramic materials (cermets) when replacing the carbon anode array, it was decided to use the classic copper-nickel alloy CuNi44Mn1, which has a minimum iron content (reducing the grade of aluminum) and characterized by thermal stability at electrolysis temperature. Based on the electrical characteristics of the basic process and taking into account the recommendations of “RUSAL Laboratory” specialists, the dimensions of the metal inert anode are determined and recommendations are given for the reconstruction of the above-mentioned electrolyzer when switching to a new aluminum production technology.

RUDN Journal of Engineering Research. 2022;23(1):15-22
pages 15-22 views

Creation and application of mobile multifunctional energy technology complexes

Lachuga Y.F., Godzhaev Z.A., Redko I.Y.

Abstract

Currently, there are processes of transformation of energy systems in the world, as a result of which a new architecture is being created. The main factors driving the transformation of energy systems are a significant reduction in the cost of energy generation and an increase in electricity consumption, including distributed generation, electric transport, electrification of mobile energy facilities in the agro-industrial complex, energy storage management system, energy supply and intellectualization of production. Factors in the development of energy technology complexes are also the possibility of creating environmentally friendly farms using renewable energy sources in areas with difficult-to-access logistics of energy resources, such as gasoline and diesel fuel. Reducing emissions of CO2 into the atmosphere and improving the environment is by no means the only fundamental result of the development of energy technology complexes. This paper reviews the basic principles of creating mobile energy complexes, based on the analysis. Multi-criteria formulation of the task for evaluating the effectiveness, allows you to identify the most appropriate quality criteria and functional limitations.

RUDN Journal of Engineering Research. 2022;23(1):23-29
pages 23-29 views

Generating hydrodynamic surfaces by families of Lame curves for modelling submarine hulls

Karnevich V.V.

Abstract

This paper investigates the construction of hydrodynamic surfaces, which are defined by algebraic equations and describe the theoretical hull of a vessel. A technique for automation of generating hydrodynamic surfaces is proposed. This technique allows to create a vast variety of hull shapes, for which Lame curves with variable exponents are used as surface generator lines. The surface is constructed by a family of curves in one of the three mutually perpendicular planes, which permits to obtain three algebraically different, but geometrically identical surfaces. This paper introduces parametric equations for each of the three surfaces, generated by families of sections, buttocks and waterlines in the form of Lame curves. The algorithm of modelling a submarine hull with different fore and aft bodies and a parallel middle body by a closed surface is demonstrated and the modelling results are illustrated. The presented technique may be effectively applied at the early stages of ship design when choosing the optimal hull shape, for which a number of surfaces need to be considered.

RUDN Journal of Engineering Research. 2022;23(1):30-37
pages 30-37 views

Evaluation of the gasoline electromagnetic injectors performance by the average absolute deviation values of the test liquid volume

Khodyakov A.A., Khlopkov S.V., Basova V.V.

Abstract

An assessment of the technical condition of electromagnetic injectors (EMI) of gasoline engines with direct fuel injection has been carried out. The technical condition of the EMI was assessed using a stand for cleaning and testing injectors. A step-by-step cleaning of the nozzles from contamination was used, that is, in two stages. At the first stage, the “extra flushing” mode (without ultrasound) was applied. The detergent for this cleaning method was anhydrous BG-210 washing liquid, consisting of hydrotreated heavy and light oils, Stoddard’s solvent, 2-butoxyethanol, isopropyl alcohol, and xylene. At the second stage, the nozzles were cleaned for 10 minutes in an ultrasonic bath filled with LAVR Ln 2003 washing liquid. It is shown that the calculated average absolute deviations of the test liquid volume reflect not only the presence of contaminants in the nozzles, but also illustrates the cleaning process. The average absolute deviations of the volume of the test liquid after chemical treatment and exposure to ultrasound are 2-9 times lower than those obtained in nozzles that were not cleaned with chemical reagents and ultrasound.

RUDN Journal of Engineering Research. 2022;23(1):38-46
pages 38-46 views

Elimination of causes of crack formation in the slider of a powerful crank forming press

Kornilova A.V., Zaya K.

Abstract

It is known that during long-term operation of crank machines for cold sheet stamping, which consists in cyclic loading of the structure with mechanical stresses, fatigue degradation of the metal occurs, leading to the occurrence and growth of cracks. Nevertheless, the main trend of modern Russian approaches to modernizing the park of forging and pressing machines is the desire to preserve large metal-consuming parts of stamping presses when replacing the control system and hydraulic and/or pneumatic components of additional actuators. Practice has shown that such approach is economically and technologically justified. For countries that do not have the capacity to manufacture stamping machines of their own brands, there is a need to purchase equipment abroad (including Russia), usually for economic reasons in the secondary market after a long period of operation. In this case, competent pre-sale preparation is required in order to avoid emergencies and equipment failures after its installation at the purchasing enterprise. Ensuring the durability of crank stamping machines after a period of long-term operation is an urgent task, both for the industry of developing countries and for the Russian one. Using the example of a powerful crank stamping press, during the pre-sale preparation of which cracks in the slider were revealed, a way to eliminate the causes of cracking during its further operation is shown.

RUDN Journal of Engineering Research. 2022;23(1):47-56
pages 47-56 views

Modification of copper alloys with ultrafine powders

Malkova M.Y., Zadiranov A.N., Gerasimova I.N., Grusheva T.G.

Abstract

Modification of metal melts by mechanochemically activated ultrafine powders (UDP) makes it possible to obtain ferrous and non-ferrous metal alloys with fundamentally new performance properties due to changes in the structure of metal alloys. The purposes of this work were to analyse the efficiency of the process of modifying copper alloys with ultrafine powders and to develop a special device for introducing a modifier into the melt. Experimental studies of the process of modifying melts of aluminum, silicon and tin bronze with mechanochemically activated UDP of natural graphite, as well as silicon and aluminum oxides with a fraction of -100+0 microns in a concentration of 0.2-0.25 % were carried out. It is shown that the modification of bronze melts by the above-mentioned powders affects the microstructure of alloys, intensively grinding it in comparison with the initial structure. It was found that the reduction in the size of the dendritic cell in comparison with the initial alloy reaches 25%, and the micrograin - 230%. Grain grinding leads to an increase in the mechanical properties of copper alloys, such as Brinell hardness HB, tensile strength σb, elongation δ. For more efficient implementation of the process of modifying metal melts with ultrafine powders, an original design of a device for introducing modifiers into the melt has been developed, characterized by simplicity and cost-effectiveness of execution.

RUDN Journal of Engineering Research. 2022;23(1):57-64
pages 57-64 views

Experimental studies of the impact of waves’ loading on the underwater pipeline

Mordvintsev K.P., Korneeva E.M.

Abstract

This work is devoted to the results of experimental studies on the impact of wave loading on a buried pipeline. Currently, there is an active development of large deposits located on the shelf and the northern rivers (Ob Bay, Yenisei), from where delivery to the places of consumption should be made. The most convenient type of transportation is the pipeline. Its route often crosses water areas, the size of which can reach five kilometres or more. Such dimensions allow the occurrence of a wave load acting on the pipeline. The issue of pipeline stability is especially relevant for designers in order to avoid accidents during operation. Nowadays, the regulatory documentation does not address this issue. Only the force of Archimedes is considered, without taking into account the wave action. The causes and process of moving the pipe up in the ground are difficult to theoretically analyze, therefore, it is mainly studied by empirical methods. In this work, the dependence between the wave load and the buoyancy force is established experimentally. The series of experiments was conducted with changing wave parameters and pipeline depth. This article will be useful for submarine pipeline designers.

RUDN Journal of Engineering Research. 2022;23(1):65-74
pages 65-74 views

This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies