Vol 21, No 3 (2020)

Aviation and rocket and space technology
Development of a design methodology for heat-loaded dimensionally stable elements of carbon plastic construction for a remote sensing of the Earth space equipment
Gorodetskii M.A., Mikhaylovskiy K.V.
Abstract

One of the most important tasks of the Federal Space Program of Russia for the period until 2025 is the creation of spacecraft for remote sensing of the Earth. An integral part of the design of this class spacecraft is the determination of the parameters of the orbits that are most effective from the standpoint of information content, energy supply and the duration of active existence. In orbital flight, the temperature state of spacecraft in a complex way varies in time and space. The inhomogeneous temperature field of the structural elements of spacecraft can cause shape distortion, which adversely affects the performance of targets. A technique for a comprehensive analysis and determination of the platform composite design parameters, which is part of the spacecraft for remote sensing of the Earth is proposed. The conditions of thermal loading for flight in a sun-synchronous orbit are considered and mathematical modeling of the operating conditions that ensure the effective operation of such spacecraft is performed. The results of modeling the thermal regime of options for composite platform designs are presented. The technique will be useful in determining the complex of orbital characteristics of the Earth remote sensing satellite at the stage of technical proposals.

RUDN Journal of Engineering Researches. 2020;21(3):159-165
views
Assessment of wing deformation influence on airload determination at the initial design stages
Baranovski S.V., Mikhaylovskiy K.V.
Abstract

At designing aircraft, much attention is given to the wing, as one of the most critical elements of the airframe. It is necessary to have a clear-eyed outlook at response sequence, efficiency of various factors and calculation features on the receipt timing and quality of the result. In addition, the design of a structural element is a complex multidisciplinary task affecting various fields of science, which is complicated by the use of polymer composite materials. In the furtherance of solving the urgent task of the methods of designing of a polymer composite wing, it is necessary to determine the influence of wing deformation on the airload used in the calculation and determination of product parameters. Methods of designing of a polymer composite wing used at the initial stages and taking into account the choice of the external appearance, justification of the structural arrangement and load-bearing elements. The paper considers the flow of air over the wing of a passenger airliner and analyzes the pressure values for various flight modes. A comparison is made of the initial theoretical wing surface and deformed during flight, and the difference in loading of the considered options is determined. A future methodology of polymer composite wing design based on parametric modelling will take these results into account and make use of them.

RUDN Journal of Engineering Researches. 2020;21(3):166-174
views
Mechanical engineering and power-plant
Less wear on the piston skirts of internal combustion engines
Asoyan A.R., Gorshkov A.S., Israelyan A.H.
Abstract

A significant proportion of mechanical losses in internal combustion engines accounted for mechanical losses in the cylinder-piston group. Depending on the operating modes of the internal combustion engine, contact interaction in the piston-cylinder pair is possible, which leads to wear of the working surfaces of the resource-determining elements and a decrease in the operational life of the power unit as a whole, in connection with which the reduction of friction losses in the internal combustion engine elements and the piston - cylinder liner coupling in particular is relevant. Both domestic and foreign researchers are engaged in the solution of the above described problems, various profiles of pistons, methods of calculating the parameters of the oil layer are proposed, but the practical state of the issue determines the relevance of research in this direction. The paper considers the possibility of reducing the wear of piston skirts by reducing the contact surface in conjugation and providing an oil film in the friction zone, regardless of engine operating conditions. This opportunity is realized by forming a certain macro profile on the working surface of the piston skirt. The formation of the macrorelief was carried out by means of surface plastic deformation, with the reciprocating movement of a spherical tool on the machined surface.

RUDN Journal of Engineering Researches. 2020;21(3):175-180
views
Mechanical engineering and machine science
Capacity of roller mill for cement grinding
Kalyagina N.V., Karpukhin I.I., Kornilova A.V., Silverstov I.N.
Abstract

Engineering for the cement industry is part of the heavy industry. The cement industry is the main supplier of raw materials for the production of concrete and reinforced concrete. For grinding cement, two types of mills are used - ball and roller. Recent decades have proven the great effectiveness of a vertical roller mill for grinding raw materials. Its effectiveness, combined with the implementation of drying, grinding and separation in one unit, gives it an undeniable advantage over a ball mill. This explains the significant increase in the share of roller mills in the cement mill market. The grinding process in such mills occurs due to abrasion, respectively, in the process of work wear of the rubbing parts of the mill occurs. The work evaluated the performance of a mill with smooth disk rolls. During the study, the cause of the destruction of the sectors of the mill produced by FLSmidth, operating in the Russian Federation, was identified. The study revealed the causes of the destruction of the details of the roller mill: with the simultaneous impact of the workload and the displacement of the sectors resulting from intensive wear, the total equivalent stresses exceed the value of the endurance limit under cyclic loading. Therefore, the accumulation of fatigue damage to the material, the formation and growth of cracks, which adversely affects the performance of the mill. A number of measures have been proposed to increase the operability of mills of this design.

RUDN Journal of Engineering Researches. 2020;21(3):181-188
views
Construction of routes in augmented reality using GIS technologies
Yudin A.V., Stratienko A.N., Madumarov M.M., Myrnenko M.A.
Abstract

At present, one of the promising directions of development in the field of information technologies is augmented reality, which offers access to real-world data through the device's camera using an interactive data display approach. Augmented reality is widely applied in various areas of life: beginning from game applications, finishing with professional applications for briefing, training for personnel in a manufacturing sector, heavy mechanical engineering and the high-tech sector, thereby providing an opportunity to use virtual instructions for implementation of the qualified operations. Also, the main way to apply augmented reality is location service - the possibility to track the position of objects on the geographic information map in real time. The article discusses ways of constructing routes in augmented reality on the field of location service data and explores the peculiarities of application. Problems identified when applying the above method are analyzed. An example of route construction is given on the map with reference to location service data and on the stage of augmented reality with calculated coordinates of route points. Methods of converting geographical coordinates into coordinates of augmented reality scene are presented.

RUDN Journal of Engineering Researches. 2020;21(3):189-196
views
Earth science
Actual situation and prospects for the development of the phosphate-raw material base of Russia
Georgievskiy A.F., Bugina V.M.
Abstract

The article analyzes the state of the phosphate raw material base in Russia and its role in the economic development of the country and in domestic agriculture especially. The problems that prevent the creation of a modern powerful phosphate production capable of satisfying the existing demands of agriculture in phosphoric mineral fertilizers are highlighted. The possible directions of the development of the phosphorus industry in the regions for the near and distant prospects are analyzed. The aim of the article is to analyze the current state of the domestic mineral resource base to produce phosphorus fertilizers, the acute shortage of which hinders the development of the country's agriculture. Actual base for research was mainly processed materials from specialized scientific articles and publicly available publications. In addition, data collected by the authors during thirty years of studying phosphorite deposits in Russia and foreign countries were involved. The analysis of published materials of leading Russian producers of phosphorus products, mining companies, databases of specialized federal and regional geological companies. It is concluded that before the country's geological services, the most important task remains to identify deposits of high-quality phosphate ores, and especially in Siberia and the Russian Far East. Significant prospects for the development of these regions are opened by the Northern Sea Route. The planned pace of its development offers unique opportunities for the economic development of the Taimyr-Anabar region, where huge resources of apatite-bearing carbonatites of the Tomptor alkaline massif and Meimech-Kotuy province are concentrated.

RUDN Journal of Engineering Researches. 2020;21(3):197-207
views
Civil Engineering (Construction)
Geometric nonlinear analysis of thin elastic paraboloid of revolution shaped shells with radial waves
Gil-oulbé M., Markovich A.S., Ngandu P., Anosova S.V.
Abstract

From the old ancient types of roof and dome construction, various forms of shells have been discovered which attract special attention. A shell is a structure composed of sheet material so that the curvature plays an important role in the structural behaviour, realizing its spatial form. There are different types of shells, namely thick and thin shells. G. Brankov, S.N. Krivoshapko, V.N. Ivanov, and V.A. Romanova made interesting researches of shells in the form of umbrella and umbrella-type surfaces. The term “nonlinear” refers to a given structure undergoing a change in stiffness in its loaded state. There are basically three different types of nonlinearities: geometric, physical and contact (boundary condition nonlinearity). For further analysis of the stress-strain state, a paraboloid with an inner radius of 4 m and an outer radius of 20 m and the number of waves equal to 6 was considered. The test shell is made of reinforced concrete. The minimum load parameter at which the shell loses stability indicates a more than three times the margin.

RUDN Journal of Engineering Researches. 2020;21(3):208-214
views

This website uses cookies

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

About Cookies