A review of methods for calculating microclimate parameters is performed. The possibility of using existing mathematical models to describe the aerodynamic characteristics of ventilation valves and optimize their performance indicators: productivity, hydraulic resistance, density, response time and other parameters that form their efficiency is considered. In order to assess the correspondence of the obtained mathematical dependencies, a physical experiment was conducted. The adequacy of the mathematical model was verified by comparing the results of calculating the parameters of the internal environment in the SolidWorks software and computing complex with experimental data.
Keywords: microclimate parameters, heat and mass transfer, mathematical modeling, heat transfer resistance, experimental study of microclimate, air mobility, valve
In the past few years, such objects have begun to be taken outside the city limits and rebuilt in new, undeveloped territories. And on the vacated territory, a new development begins with the intensive development of underground space. The strategic innovative approach to the implementation of projects for the development of the modern city released by the industrial territory is an urgent answer to the question of a completely new understanding of the comfortable environment, in which everything is involved: zoning of the development territory, laying new roads (city streets), underground structures and communications, transport accessibility, environmental friendliness of construction. Without understanding that the problem of forming a living space is complex, in the end, comfortable conditions of human existence will not be obtained. Various modern green building standards are based on this.
Keywords: redevelopment, green standard, BREEAM, industrial territories, industrial facilities, reconstruction, renovation, complex development of the territory, certificate
The problem of studying the peculiarities of sound propagation in shallow seas is an urgent task of hydroacoustics, since it is associated with human production activities in coastal zones and waters of shallow seas. A shallow sea for a sound field is a waveguide in which certain modes propagate. Features such as "extinction" modes and dispersion distort the picture of the sound field. There is also a complex interference situation due to reverberation interference and multiple re-reflections. To avoid information loss, it is proposed to use narrowly directed parametric radiation without side lobes. The issues of equipment selection are considered, the law of temporary automatic gain control (TAGC) for the study of bottom layers is calculated. The results of the analysis of echograms for depths of 1-2 m are presented. The possibility of identifying layers and anomalies is shown.
Keywords: shallow sea, sound propagation, modality, waveguide, TAGC's law, structure data, layers, profilograph, anomalies
This publication is devoted to the method of applying coatings from various materials to carbide cutting tools by the method of electrospark alloying, as well as the experience of using this method in practice. The formation of the surface layer, its structure were studied, and cutting tests were carried out. It has been found that nickel and aluminum coatings are more resistant than copper and zinc coatings.
Keywords: coating, carbide, cutting tool, wear, electrospark alloying, roughness, hardness
The article is devoted to the development of models and algorithms for calculating control (advisory) actions when training operators of technological processes (on the example of reloading processes and, in particular, portal cranes) on computer training complexes (CTC). A complex of models and algorithms is proposed, based on which control actions are calculated regarding discrete crane controls and the possibility of moving the load to a target position with minimization of oscillations at the end point is provided. These models and algorithms use variable parameters of the technological process, described by linguistic variables, and customizable characteristics of crane models and engines, which allows calculating control actions depending on the type of crane, the specifics of the technological process, the training methodology used for operators and other significant factors. Application of the advisory system based on the developed models and algorithms promotes to improve the training process for operators of reloading cranes at CTC and, as a result, to reduce the probability of emergency situations, reduce time and energy costs.
Keywords: computer simulator, reloading processes, portal crane, advisory system, control actions, mathematical modeling, fuzzy logic controller
This article describes the process of inventorying equipment in a typical IT department. A new approach to inventory is proposed, which will eliminate the "double work" and solve a number of typical problems. The relationship with an already developed product for monitoring network infrastructure is described.
Keywords: monitoring, network infrastructure, inventory, QR code, Telegram, information technology, information technology department
This paper analyzes the state of the automation level of energy facilities. The most rational method of assessing the level of automation is given: consideration of each energy facility (generating enterprises, transport companies, consumers) separately for the most effective assessment. The analysis of the level of automation of generating companies on the example of thermal power plants is given. A solution aimed at increasing the level of automation is proposed. The analysis of the level of automation of transport companies and consumers on the example of thermal energy is also given. The ways of increasing the level of their automation aimed at improving the efficiency of transmission and use of energy are proposed. The article presents a number of advantages of the introduction of automated systems at energy facilities on the example of an automated dispatch control system at power plants and substations. A number of the most promising solutions for increasing the level of automation of energy facilities are also presented.
Keywords: automation, energy facilities, automated dispatch control, energy complex
It was necessary to develop a filter design option for implementing it on an FPGA in conditions of limited FPGA resources and processing time. Options for constructing filters and sequential optimization of the structure for implementation on an FPGA were considered. Two models were built using the Matlab environment, where the results of signal processing with filters were compared for the same parameters. Simulations have shown that the filters are unique.
Keywords: DSP, FIR filter, pipeline, FPGA
The object of the research is the utilization heat exchanger. The purpose of the work is to develop a design of a heat exchanger (HA) used to recover the heat of exhaust gases from a gas turbine unit (GTU) with an increased thermal power. In the process of work, the calculation and numerical modeling of the new design of the heat exchanger was carried out. The result of the research was the design of a gas-air heat exchanger, which requires 6.5% less flow rate of the coolant (exhaust gases) compared to the prototype.
Keywords: heat exchanger, heat utilization, energy efficiency of a gas turbine unit, numerical modeling, gas-air heat exchanger
The article discusses topical issues related to modeling the physical processes in the operation of solar photovoltaic batteries. In the course of the research, the simulation of photovoltaic batteries was carried out in the MATLAB / Simulink / Simscape simulation environment. The output current of the solar cell is chosen as the main electrical parameter. The model is tested using the characteristics of the ABi-Solar P60270-D polycrystalline photo module.
Keywords: photovoltaic batteries, MATLAB / Simulink, voltage, solar energy, capacity, defects, control
The control of the fabric in the technological chain determines the structure of this very chain. The article uses a probabilistic model to assess the feasibility of re-processing fabric in finishing production.
Keywords: fabric, marriage, quality, batch, product, technological defect, reprocessing, profit, loss
The paper studies the issue of the influence of the quality of the computational triangular grid on the accuracy of calculations in various computational problems. There is a well-known example of Schwartz, which shows that the approximation of a smooth surface by a polyhedral surface can give very large errors for calculating the surface area. This is due to the quality of the constructed triangulation of the surface. Therefore, it is natural to expect that there is some connection between a certain triangulation characteristic and the accuracy of solving some computational problem. In the presented article, as such a characteristic, a value is chosen - the average value of the minimum sine of the angle of all triangles of the computational grid. In the course of numerical experiments, the Dirichlet problem for the Laplace equation in a circular ring was solved, in which the error of the approximate solution was calculated (the gradient descent method was used to find a solution to the corresponding variational problem.). For the ring, a series of triangulations was constructed with a uniform division along the angle and a non-uniform division along the radius in polar coordinates. In this example, a linear dependence of the error on was shown. The article presents both the results of the calculation with different values and the calculation of the correlation coefficient of the studied quantities.
Keywords: boundary value problem, Delaunay triangulation, calculation accuracy, Dirichlet problem, mathematical modeling, triangular mesh, minimum triangle angle, piecewise linear approximation, variational method, Laplace equation
This article considers one of the parts of the development of a device for determining the magnetic characteristics of ferromagnetic materials with a shape memory effect. A functional diagram of the device has been developed. The operation of the device was simulated and the behavior of the shape memory alloy was studied. The error in determining the magnetic characteristics of the FMSF using the magnetizing setup of the developed device did not exceed 0.25%.
Keywords: magnetostrictive materials, basic magnetization curve, magnetic shunt, magnetic flux
The aim of the study is to develop an "evolutionary model" of a transport interchange complex (TIC) - as a kind of ”growth point" of an aeropolis. Methods of “prognostic” and “structural-morphological” modeling of TIC are used for reasonable planning of the growth and development of the aeropolis. Five intermediate architectural and typological models of the transport and transfer complex have been identified: 1) bus station; 2) bus station with logistics center; 3) intermodal complex station; 4) transport and business center; 5) transport and public complex. Its "structural and morphological units", which include: a) functional components; b) structural and tectonic "units"; c) communication "framework"; d) elements of the growth of the aeropolis. A similar diachronic (developing) model of a transport interchange complex ensures its phased planning, optimal functional zoning of the facility for each intermediate phase, which will allow it to be self-sufficient at the early stages of operation. architecture.
Keywords: architecture, shaping, functioning, spatial development, transport interchange complex, transport interchange hub, transport infrastructure, aeropolis, model, structural and morphological approach, social and business center
This article addresses a number of issues related to the environmental friendliness of motor vehicles. Modern trends in the transition of the market to electric vehicles, and the problem of recycling and recycling of electric vehicle elements are considered. It was revealed that the transition from cars from ICE to electric vehicles is not yet fully justified from the point of view of ecology.
Keywords: electric car, environmental safety, waste, battery, disposal, recycling
Research in the field of design of buildings and structures has shown that the level of implementation of BIM technologies in different countries is at different levels. The availability of a regulatory framework in this area, financial assistance to construction organizations during the transition to BIM modeling contribute to raising the level. The article also provides a justification for the use of BIM technologies in ventilation systems, taking into account the requirements for these systems.
Keywords: BIM modeling, ventilation systems, 3D design, Autodesk Revit, implementation levels, information modeling, BIM technology, regulatory and technical base
This article is devoted to the study of indoor air quality in a higher education institution: assessment of the distribution patterns of suspended solids by equivalent diameters (RM0.5, RM1, RM2.5, RM5 and RM10).
Keywords: indoor air, indoor air quality, air pollution, dust, solid suspended particles, PM2.5, PM10
Modern trends of the concretes studies have been considered. Properties of the materials and additives used have been cited. There has been undertaken designing an experiment on a complex modifying additive application for a fine fibre-reinforced fine-sand cocrete. The results of the studies undertaken have been analyzed with regard to their statistical significance. On the bases of the reseach results there have been acquired regression equations for objective functions responses, namely ultimate strength on both compression and bending, and average density of fine fibre-reinforced concrete. There have been produced contour plots and those of response function surface - ultimate strength under compression for all combinations of the both factors. There have been determined the composition of the modifying additive, which ensures maximal strength properties for fine fibre-reinforced fine-sand concrete.
Keywords: fine concrete, complex additive, designing an experiment, strength, regression equation, plots of response function surface
The article is devoted to the issue of improving devices for cleaning gas station emissions from hydrocarbon vapors to improve the environmental safety of zones and territories of residential development. The largest part of the release of gasoline vapors entering the local aspiration systems is associated with the filling and emptying of fuel storage tanks at gas stations. It is known that emissions of benzene vapors belonging to the second hazard class have a significant problem in terms of exceeding the maximum permissible concentrations at the boundaries of the sanitary protection zones of gas stations and nearby residential buildings. Creation of new highly efficient technologies and devices for reducing the volume of pollutant emissions from gas filling complexes, while reducing operating costs by the amount of emissions and waste generated, developing reliable gas trapping devices of acceptable low material and energy consumption for gas station aspiration schemes is an urgent task. Another reason of elaborations’ needs of those gas trapping devices are reducing operating costs and environmental payments for emissions and waste. It was carried out environmental – economic research to verify justification to use absorption-type apparatuses within an absorbent mixture of sodium-magnesium salt’s solution (bischofite solution) and waste water of from a local purification device. It was allowed reducing emissions from sources of gas station aspiration schemes using capturing gasoline hydrocarbon vapors by mention above apparatus. It is essential reducing negative emissions’ impact of harmful substances and an additional amount of generated waste of gas stations. There are presented the results of calculating volume of the fees’ environmental damage, and economic efficiency of the use the proposed type of sorbent’ apparatus in this article also. The use of the proposed device in gas station aspiration schemes allows deceasing environmental payments for emissions including carbon taxes and fees and additional operating costs in terms of the use of consumables. The successful tests carried out have shown the reliable and efficient operation of the pilot plant with the proposed device at the gas station. The successful tests carried out have shown the reliable and efficient operation of the pilot plant set up with the proposed device that decreased environmental payments for emissions, waste and operating costs.
Keywords: To improve emission treatment devices and reduce the generation of gas station's waste
Atmospheric air is the most important life-supporting natural environment that has developed during the evolution of the Earth. The results of environmental studies, both in Russia and abroad, indicate that pollution of the surface atmosphere is the most powerful, constantly acting factor of impact on humans, the food chain and the environment. In this regard, the urgency of the deterioration of the ecology of the surface environment in modern cities has increased disproportionately. The development of modern cities, caused by the need to improve the living environment, contributes to the creation of new buildings and structures, the development of transport and engineering infrastructure. As a result, the density of urban development and the congestion of transport networks increase, which leads to environmental pollution and complicates the ecological situation in cities. The article analyzes the ecology of the largest cities in Russia using the example of the city of St. Petersburg and assesses the aerodynamics of urban space. Convective flows occurring in the urban space are identified as one of the important factors in improving the ecology of the urban environment. The analysis of such factors as harmful emissions from vehicles and disturbed due to dense development of air exchange in urban areas, affecting the ecology of urban space.
Keywords: ecology, aerodynamics, air exchange, air pollution, transport infrastructure, high-rise building, urban development, aeration, energy consumption
The condition of a metal cylindrical mesh shell with external horizontal trusses is investigated. The basic principles of forming the structure are considered, taking into account the use of a support rib to align the faces of a mesh surface. The analysis of important force factors and deformation parameters of the reinforced shell is carried out taking into account all possible combinations of loads. The regularities of the system operation are determined and the influence of the location of the support trusses on the behavior of the structure is estimated. Vulnerable areas with maximum longitudinal forces in the elements and the greatest displacements of nodes were identified. An increase in stiffness outside the shell plane in the transverse direction was obtained and a positive redistribution of forces over the surface was recorded. An acceptable result was established from the point of view of ensuring the stability of the structure and the increased resistance of the shell to deformation was noted.
Keywords: cylindrical mesh shell, side elements, horizontal trusses, design parameters, forces, displacements