The development of digital technologies stimulates widespread automation of processes in enterprises. This article discusses the problem of determining the values of the oil indicator of a transformer from the resulting image using computer vision. During the study, the device of the MS-1 and MS-2 oil indicators was studied and the features that must be taken into account when recognizing the device in the image and determining its value were considered. Based on the processed material, a method for recognizing device elements in an image has been developed using the OpenCV library and the Python programming language. The developed method determines instrument readings at different angles of rotation and in different weather conditions, which confirms the effectiveness of the proposed method.
Keywords: technical vision, oil indicator, contour recognition, OpenCV library
This study examines the combination of several non-destructive partial discharge (PD) detection methods to improve the accuracy of their detection. An analysis of methods for detecting PD in high-voltage insulation, a consideration of their features, and an analysis of the possibility of combining them to achieve the most accurate measurements were carried out. Analysis of the practical effectiveness of combining methods based on the developed variations of installations operating on the principles of two or more detection methods. Options for installations for PD detection that combine two or more detection methods are considered. A conclusion is given about the possibility of combining various methods of detecting partial discharges, taking into account the peculiarities of this type of combination. The simplest and most effective at the moment is the use of measuring cells that combine electromagnetic and acoustic detection methods.
Keywords: partial discharges; non-destructive testing of insulation; high voltage insulator; diagnostic methods for insulators
A numerical study of heat transfer and hydrodynamics in plate heat exchangers with corrugated fins was carried out. The effect of corrugation pitch on heat flow and pressure drop was studied. The study was carried out using computational fluid dynamics in the ANSYS software package (v. 19.2). The results of the study showed that increasing the corrugation pitch from n = 5 to n = 9 leads to an increase in heat flow of 10.83% and a pressure drop of 28.30%.
Keywords: plate-fin heat exchanger, corrugated fins, heat transfer, hydrodynamics, numerical study, calculation, heat flow, pressure drop, energy efficiency, cooling system
Using numerical modeling, a study of heat transfer and hydrodynamics in plate heat exchangers with corrugated fins was carried out, while the height of the corrugation profile varied from 2 to 4 mm. The influence of profile height on heat flow and pressure drop was studied. It was revealed that an increase in the profile height leads to an increase in heat flow up to 34.05% and pressure drop up to 54.54%.
Keywords: corrugated heat exchanger, cooling system, microelectronics, profile height, heat flow, pressure drop, heat transfer, hydrodynamics, calculation, numerical modeling
A numerical simulation was used to investigate heat transfer in plate-fin radiators with round fillet profiles of various depths, including 0.55 mm, 1.1 mm, and 1.5 mm. The issue of flowing air around a radiator with a mass flow rate of 10-3 to 4·10-3 кг/с and a temperature of 293 K was solved. The radiator was heated using a heater, whose temperature was set from 323 to 353 K. Changes in heat flow, pressure drop, and energy efficiency indicator were shown depending on the air mass flow, according to the calculation results. The research findings indicate that the radiator featuring round fillet profiles and a depth of 1.65 mm exhibits the highest heat flow and energy efficiency indicators, as well as the lowest pressure drop.
Keywords: radiator, cooling system, numerical modeling, computational fluid dynamics, heat transfer, heat flow, pressure drop, energy efficiency, calculation, electronics
Using numerical simulation, particle deposition in a porous heat exchanger was studied; the mechanism of sediment formation was sinvestigated, and the influence of sediment on the heat flow was assessed. The influence of porous heat exchanger length, dust particle size, and air flow velocity on particle deposition efficiency, particle breakthrough, and heat flux value was studied. Research results have shown that with increasing length of the heat exchanger, the efficiency of dust particle deposition increases, which leads to the formation of sediment. In turn, the sediment reduces the value of the heat flow from the porous heat exchanger. Depending on the length of the heat exchanger and air velocity, the reduction in heat flow is 3.43-7.27%.
Keywords: porous media, heat exchanger, particle deposition, deposition efficiency, particle breakthrough, sediment, heat flow, numerical modeling, computational fluid dynamics, calculation
Using numerical modeling, we performed studies of the influence of the angle of inclination of the plates of the regenerative heat exchanger element on the heating time and pressure drop. The studies were conducted for models of heat exchange elements with lengths of 6 and 20 mm. Depending on the length of the element, the angle of inclination of the plates was: 10°, 20°, 30°, 40° (at L=6 mm) and 3°, 6°, 9°, 12° (at L=20 mm). At the boundary of the calculation area, the air flow velocity and temperature were established, namely 1 and 3 m/s, and 303 and 973 K. The research results demonstrated that increasing the angle of inclination of the plates helped reduce the heating time of the regenerator by 38.56-49.1%, depending on the length of the heat exchange element, the speed and temperature of the air flow.
Keywords: heat recovery, honeycomb heat exchanger, numerical modeling, calculation, heating time, pressure drop, heat exchanger geometry, angle of plate, air flow velocity, air flow temperature
Using numerical simulation, we carried out studies on the effect of the length of a porous heat exchanger on the deposition of dust particles. The heat exchanger models with lengths of 5, 10, 20 and 30 mm were the subject of the studies. At the boundaries of the computational domain, we set the air velocity at 0.1, 1, and 5 m/s and the diameter of dust particles from 10-7 to 10-4 m. Research results have shown that with increasing length of the porous heat exchanger, the efficiency of dust particle deposition increases. This can lead to a decrease in the thermal and hydraulic characteristics of the heat exchanger.
Keywords: porous media, heat exchanger, numerical simulation, calculation, deposition of dust particles, heat exchanger length, air flow velocity, particle diameter, air cooling, microelectronics
This article discusses the relationship of all stages of the life cycle of buildings on the basis of information-analytical system IAS HCS. The full life-cycle cost of a 1,000-seat school was calculated. Using the IAS HCS program, we made calculations of the costs of repair work on three models: without taking into account any repair work, taking into account the repair of the main structural elements and taking into account the repair of all elements, based on the standard operating time. Real estate life cycle cost analysis can be performed for both new and existing buildings of any type (residential and public). Evaluation of the total costs of the full life cycle of the object can be applied by both the developer and the owner of the building to further improve the management system of the property.
Keywords: lifecycle of construction object, information modeling, social facilities, cost of repair work, replacement cost