Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies最新文献

{"title":"Optimization of operating modes of ship refrigeration plant with artificial cold accumulator","authors":"Alexander Evgenyevich Semenov, A. I. Andreev","doi":"10.24143/2073-1574-2023-3-65-73","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-65-73","url":null,"abstract":"The ways of optimizing the operation of a refrigeration unit for fishing and refrigerated vessels with the additional inclusion of artificial cold storage devices are investigated. For this purpose, a new technology of cold storage has been developed on the basis of a refrigerating machine with direct contact between media and ice production. The refrigerant RC318 was taken as freon which does not form crystalline hydrates. Based on this, the optimization of the operation of a single-stage refrigeration machine was carried out using the Lagrange multiplier method for the target function of energy consumption, calculated by reducing the exergy flow in the system. The data obtained show the relevance and prospects of using cold accumulation on ships to reduce energy costs for the operation of refrigeration equipment and increase the autonomy of fishing vessels. Optimization according to the given method leads to two modes of operation of the refrigerating machine, as the most optimally beneficial in terms of operating conditions during the generation of cold. Optimization was carried out for two schemes for including a cold accumulator in the cold supply system. The proposed optimization methods make it possible to reduce the energy consumption of refrigeration units to the level of design loads, and to compensate for peak loads with the help of cold from batteries. Further research in this matter is aimed at reducing the size of the battery, increasing its energy efficiency and developing recommendations for inclusion in the general schemes of ship refrigeration plants based on mathematical optimization models and field experiments. It also plans to further improve the methods of cold accumulation based on ice generation with direct contact of media inside refrigeration units.","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130133477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Professional orientation of engineering specialties within special course in physics","authors":"V. Bykova","doi":"10.24143/2073-1574-2023-3-114-124","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-114-124","url":null,"abstract":"The article highlights the peculiarities of teaching physics to the students of Astrakhan Technical University during a special course “Operation of marine electrical equipment and means of automatics” within the framework of technical creativity workshop “Applied physics” organized under the Department of Physics. The given special course can promote realization of a variative part of the direction, according to the curriculum. The content of the special course meets didactic principles: integration, continuity and succession of training, fundamentality and professional orientation of interdisciplinary links. It was theoretically proved that such content is most fully satisfied by the special course on physics “Bases of electromagnetism and electromagnetic compatibility elements” based on integration of physical theories with technical ones in the frame of the elective disciplines “Bases of electromagnetic compatibility” which helps to form professional orientation of knowledge and abilities on physics. There is examined a theoretical component of the special course and particular tasks and solutions are given: practical problem connected with professional activity of the future specialist; the research problem, allowing to predict the expected result and to learn how to conduct the research work; the creative problem satisfying the conditions of industrial teaching. Diagrams of a DC electric circuit, a graph of dynamic loops of remagnetization of a coil, illustrations of the block “Properties of gases”, the laboratory complex “Electricity and Magnetism”, a block of generators, a diagram and model of the Brovin Kacher device, as well as its components are given as part of the exemplary tasks for students. The experience of non-contact energy transfer is illustrated. Conclusions are drawn about the practical significance of the special course in the framework of the work of the workshop of technical creativity at the Department of Physics of Astrakhan State Technical University.","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115135964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of nozzle defects on fuel consumption and modern methods of fuel equipment control","authors":"Anatoly Nikolaevich Sobolenko, Sergey Vital'evich Pastukhov","doi":"10.24143/2073-1574-2023-3-56-64","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-56-64","url":null,"abstract":"The basis of improving the vessel energy efficiency is economical operation of its power units - the main and auxiliary diesel engines, steam boilers. There has been described the smart control system for ship operation. The main parameters listed below are under constant control: fuel consumption of the main and auxiliary steam diesel engines, auxiliary steam boiler, operating time of the main and auxiliary diesel engines, auxiliary steam boiler; fuel level in consumable, settling and bunker fuel tanks; vessel speed, vessel position, weather conditions. The system includes flow meters, temperature, speed, power, and pressure sensors, GPS-station, digital converters, controllers, marine computer industrial design, monitors for parameters in the engine control room and on the bridge, special software for ships and offices. There has been determined the main goal of developing and assembling the system: to develop a reliable working tool for the crew and the main ashore office, to evaluate and control the quality of the vessel operation, to supplement the existing control methods with an improved and more understandable scheme of monitoring various parameters of the ship's operation, including fuel consumption. The results of developing and introducing the system help increase the actual energy efficiency of the vessel operation. An example of real-time fuel consumption control using the smart control system - ShipSmartView - is presented. The functionality of the system is quite wide. Graphs of the current fuel consumption which indicated the defect in the fuel equipment are given. Based on the data, overhaul of the fuel equipment was carried out and a malfunction of the nozzle - a crack - was defined. It has been proved that due to untimely detection of a malfunction, a loss of fuel was allowed.","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122009455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Technology of manufacturing samples from polymer composite materials","authors":"Maksim Alekseevich Meleshin, A. Salamekh, V. Mamontov","doi":"10.24143/2073-1574-2023-3-19-26","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-19-26","url":null,"abstract":"The article considers the materials, composition and methods of manufacturing samples from polymer composite materials (PCM). There is presented the method of testing samples of PCM for mechanical properties. For testing, plates were made from which samples from PCM were cut, based on glass roving, glass wool and polyester resin with the addition of a hardener. Using mechanical tests, the influence of the quantitative ratio of layers of glass wool and roving fiberglass has been determined when testing samples for three-point bending, stretching and compression. A scheme of structural reinforcement of PCM plates is given, graphs of the average values of breaking loads and ultimate strengths when testing samples for three-point bending, dependences of average values of breaking loads and ultimate strengths when testing samples for tension and compression are illustrated. Comparative analysis of the average values of the tensile strength of the samples during the compression test has been carried out. As a result of processing the data obtained during the study, it was found that with an increased number of layers of roving glass in the PCM composition increases the destructive load and tensile strength, compression, but the values of the applied load of PCM samples decrease during three-point bending tests. The experimental data obtained from the test results of PCM samples are the main indicators of the mechanical properties of PCM with various reinforcement schemes for their use in ship hull structures, in particular as a material for ship tanks.","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"602 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123210865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determining pressure losses in flushing pipelines by two-phase flow","authors":"Elena Gennad'evna Lebedeva","doi":"10.24143/2073-1574-2023-3-33-38","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-33-38","url":null,"abstract":"A stream of water is used in flushing ship systems and their elements. To increase the efficiency of the process, a two-phase pulsating flow can be used. This method of flushing intensification brings tangible results, but currently has a number of unsolved problems. One of these problems is the question related to the determination of energy costs for the transportation of a two-phase mixture. The energy costs for transporting the flow depend on the magnitude of pressure losses due to friction and on the orientation of the pipeline sections in space. An attempt was made to estimate the pressure loss during transportation of a mixture of water and air through a flushed pipeline. The main theoretical dependencies are determined: mixture density, velocities of various phases of the flow, volumetric and mass flow rates, mixture flow rate on volumetric and mass water-air content. A theoretical substantiation is given for determining the pressure loss during the movement of a two-phase flushing medium depending on the concentration of the gas (air) phase in the mixture. When determining pressure losses, a homogeneous model of a two-phase mixture was used as the most suitable for the flushing mode with a two-phase pulsating flow. The main calculated dependences for calculating the pressure losses for the transport of a two-phase mixture in horizontal and vertical sections of pipelines of constant internal diameter are determined. The dependence of pressure losses on gas content in horizontal and vertical sections of pipelines has been established. An assessment of the pressure loss during flushing with a two-phase flow in differently oriented sections of ship pipelines was carried out in order to determine the further effectiveness of this flushing method.","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133233462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative analysis of mathematical descriptions and pulse-width modulation methods","authors":"Vladimir Olegovich Gus'kov, Andrey Viktorovich Lavin","doi":"10.24143/2073-1574-2023-3-74-81","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-74-81","url":null,"abstract":"The article considers the mathematical description and comparison of the most common methods of pulse-width modulation (PWM) for a three-phase voltage inverter, namely vector PWM, PWM with third harmonic premodulation and classical PWM. In contrast to the classical mathematical description of PWM, a description is presented that is close to the implementation of modulation using modern microcontroller technology. The classic representation of PWM is based on comparing two signals. In this representation, the modulation pulse occurs at the moment when the modulating function is greater in value than the reference signal. When implementing PWM by a microcontroller, the pulse is placed within the period symmetrically with respect to the middle of the interval, while the pulse width is determined by the average value of the voltage modulating function. With a different mathematical description of PWM, the pulse is located differently within the modulation interval. There are presented the results of modeling and compares the mathematical descriptions of PWM methods according to the criterion of minimum dispersion of the current flowing in the load. As a result of the comparison, it was revealed that the same, differently described PWM algorithm gives different results. A comparison of vector PWM with a modified vector PWM was made. The modification consists in applying a dynamic pulse shift algorithm in such a way as to obtain a minimum of current dispersion in the load. Comparison of PWM methods was carried out at different frequencies of the reference signal; a static RL circuit was used as a load when simulating a three-phase voltage inverter. The results obtained allow us to recommend a pulse shift algorithm for implementing PWM in voltage inverters operating at relatively low PWM frequencies. Minimization of the current dispersion makes it possible to obtain improved energy and vibration-noise characteristics of the electric drive.","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122175626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On mathematical model and equivalent circuit of transformer (critical analysis of generally accepted theory)","authors":"Yuri Nikolaevich Kagakov, Vyacheslav Valer'evich Zimin","doi":"10.24143/2073-1574-2023-3-82-87","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-82-87","url":null,"abstract":"The article considers the importance of studying the mathematical model and equivalent circuit of the transformer due to the fact that transformers are the most important link in any electric power system, including control and operation systems for marine fishing and transport vessels and stationary marine technological complexes. The generally accepted theory of transformers is analyzed, and erroneous conclusions and statements complicating, and in some cases distorting the essence and interconnection of electromagnetic interactions in the device, are pointed out. In particular, the introduction of voltage into the Kirchhoff equation for the secondary winding Ů2, along with the presence of EMF in it Ė2, creates the illusion that the secondary winding of the transformer has its own independent power source. This illusion is enhanced by the physical and logical scheme, clearly indicating that Ů2, being in the load zone, it generates a current İ2. In fact, the declarative statement that the magnetic fluxes of the primary and secondary windings are connected in coordination is also erroneous. This leads to a number of erroneous conclusions. The exclusion from the mathematical model of magnetic fluxes induced by winding currents isolated from each other does not allow one to analyze the influence of electromagnetic processes in the secondary winding on the processes in the primary. These and a number of other provisions and conclusions in the generally accepted theory necessitate its critical analysis and exclusion. There are proposed different from the generally accepted approaches to the formation of a mathematical model and equivalent circuit of transformers, which lead to their significant composition and content.","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123177423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wear resistance and compatibility of test materials for scoop chain hinge","authors":"Valeriy Aleksandrovich Petrovskiy, A. Ruban, T. Khomenko, A. V. Melnikov","doi":"10.24143/2073-1574-2023-3-7-18","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-7-18","url":null,"abstract":"The current unfavorable environmental and hydro-technical situation in some regions of the country has cre-ated a number of serious problems. The government of the Russian Federation has created projects and programs where dredging is an integral part. There are carried out dredging works, among other things, by multi-bucket dredgers, where a scoop chain is the main working body. The performance and reliability of the chain depends on the quality of materials that experience high dynamic loads, and the consequences of the abrasive environment, which leads to accelerated wear of the swivel. There are given the results of the study of wear characteristics, the range of compatibility of steels and alloys of the hinged connection of the dredger bucket chain and the technology for the restoration of these elements, with an increase in the resource of the chain connection unit. Experimental studies simulating the wear of the assembly on small-sized samples determined the wear re-sistance of the materials of the pair. The method of comparative analysis with reference pairs was used. The experimental material consisted of 13 pairs, including 2 pairs of standards made of steel 110Mn13, 38CrNi3M (sleeve-finger) and steel 110Mn13 (sleeve and finger), where the remaining pairs were made of materials: steels C35K, C45K, 110Mn13, 38CrNi3Mo, wear-resistant surfacing with E – 190Cr5Si7 – LEZ – T – 590 – NG electrodes, surfacing with wire SV08A, electrodes E50A – UONI 13/55 (E513B20H), E46 - ANO-4 (E433R24) after a complex of heat treatments, chemical-thermal treatments, surface plastic deformation, where the samples were subjected to a load of 6615 N (675 kgf) in water-abrasive medium, were tested on the friction machine. Fundamental dependences are revealed and graphs of the influence of the hardness of the samples and the carbon content of the friction surface on the wear-resistant characteristics of various structural classes are plotted. Promising pairs for full-scale tests were determined: 1. steel 110Mn13 (sleeve) - surfacing SV08A with chemical-thermal treatment (finger); 2. steel 38CrNi3Mo (sleeve) - steel C35K with chemical-thermal treatment (finger); 3. steel C35K with chemical-thermal treatment (sleeve) - cladding SV08A with chemical-thermal treatment (finger).","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126098811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Statistical data on crankshaft deflections of marine diesel engine","authors":"Vitaliy Valer'evich Vyazankin, V. Mamontov","doi":"10.24143/2073-1574-2023-3-27-32","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-27-32","url":null,"abstract":"The results of the study of crankshafts that have received a deflection during operation are presented. The reasons for the appearance of the curvature of the longitudinal axis and the consequences to which this defect may lead are considered. According to the analysis of statistical data obtained from enterprises engaged in engine repair, an increase in defects of residual deformation of deflections was noted. The necessity of collecting and systematizing cases of curvature of the longitudinal axis above the permissible value is determined. The conditions for preparing shafts for defecation have been clarified. Attention is drawn to the need to take into account the results of previous measurements and the total operating time of the engine when laying the shaft approved for further operation. The object of the study is the crankshaft of the diesel engine 6 CHN 31.8/33, used in water transport as the main marine engine. Measurements of the radial runout of twenty shafts that received deflection were made. The dependence of the measurement error on the radius of the shaft neck is established. A histogram of the frequency distribution of deflections of the crankshaft frame necks depending on the repair size number is constructed and the dependence of the deflection frequency on the repair size number is illustrated. The maximum deflection of the crankshaft of 4.10 mm with an allowable deflection of 0.03 mm is fixed. The values of deflections of diesel shafts are analyzed, their dependence on the number of the repair size and the number of the frame neck on which the deflection occurred. The frequency and significant increase in the magnitude of the deflection arrow on the fourth frame neck were noted. The necessity of using the obtained statistical data on deflections for the scientific substantiation of the technology of correction of diesel krancshafts is determined.","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124472021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studying wear-resistant coatings applied to samples of structural steel used for manufacturing shafts of hydrofoils","authors":"V. Petrov, Andrey Viktorovich Fedosov, Karina Nugzarovna Shoniia, A. Butsanets","doi":"10.24143/2073-1574-2023-3-39-48","DOIUrl":"https://doi.org/10.24143/2073-1574-2023-3-39-48","url":null,"abstract":"Effective interaction of structural elements and materials from which they are made is one of the most important tasks in the design of parts and mechanisms of ship power plants. The operating experience of Meteor-type vessels has shown that the main cause of propeller shaft breakage and failure may be non-compliance with the technical requirements for the chemical-thermal processing of the shaft necks to the bearings size or poor-quality superficial coating. There has been made a comparative analysis of coating technologies, its results will significantly increase the cyclic wear resistance of the surface layer of the shaft necks of the hydrofoil ship shafting. The technologies of gas-plasma and gas-dynamic spraying, as well as electrospark alloying of the surface are considered. An instrumental assessment of the parameters of the applied protective coating quality is performed. Alloying materials for each of the methods of the surface hardening and modification are also presented. The scheme and design of the stand for testing the applied coatings for cyclic fatigue strength up to the moment of critical failure are given. The coatings deposited on the samples surfaces are studied to assess the surface microgeometry and microhardness. The samples are tested on the stand with a cyclic load at an induction motor shaft speed of 1800 rpm (30 rps). A bearing ball made of steel is used as an indenter. After testing, the focus of the coating destruction is assessed visually using a measuring and computing complex based on an optical microscope. As a result of the tests, it is revealed that the samples processed by the electrospark alloying method have the highest resistance to alternating cyclic effects, the lowest surface roughness and the highest microhardness.","PeriodicalId":129911,"journal":{"name":"Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127777737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}