Transport development

THE ROLE OF CHARTERING IN THE MANAGEMENT SYSTEM OF INTERNATIONAL FREIGHT TRANSPORTATION

2024-02-15T14:24:19+02:00

Introduction. The investigation is focused on the role of chartering in the system of managing international cargo transportation. Since the full-scale invasion of the Russian Federation on the territory of Ukraine, the international freight transportation market began to give preference to non-resident companies to continue providing services as a charterer company, therefore attention is focused on the issues of freight payment in tramp shipping through a Ukrainian resident. This situation led to problems with the payment of freight/dead freight/demurrage from Ukrainian companies to shipowners, since such currency payments were not included in the list of critical payments, which made their payment impossible, according to Cabinet of Ministers Resolution № 153 of February 24, 2022. Purpose. The purpose of this article is to investigate the role of chartering in the system of managing international cargo transportation and to highlight the problems of paying for freight on the international market in the minds of the war in Ukraine. Results. The results of the study indicate that the issue of freight payment in tramp shipping through a Ukrainian resident turned out to be important when providing the services of a freight broker in the international cargo transportation management system. Since the emergence of potential risks for the charterer’s company, it has become easier to avoid them by paying the freight through non-resident companies, in order not to face the refusals of banking institutions to pay and all the associated problems, in particular, the lay-up of the vessel due to non-receipt of freight and reputational losses. Ukraine did not deduct nearly six hundred thousand tax payments for freight. To solve the problem, steps are proposed to improve the payment of freight in the conditions of war in Ukraine and take into account in the management system of international cargo transportation: 1) development of new and improvement of existing state regulations of the Cabinet of Ministers on payment of freight and all derivatives from adding to the list of these payments as such are critical in the implementation of import and export operations; 2) improvement of communication and exchange of information between banking institutions, Ukrainian authorities and other interested parties, which will contribute to solving any problems and misunderstandings related to international transportation in Ukraine during the war. Conclusions. The war in Ukraine led to new challenges and obstacles not only for Ukrainian but also international participants of the freight market. In addition, it is worth noting that the government shows interest and takes all necessary steps to improve the situation according to the latest resolutions of the Cabinet of Ministers 05.05.2023 № 445. It was emphasized that in shipping it is necessary to take into account constant risks and unforeseen circumstances, thereby demonstrating the flexibility of decision-making in conditions of uncertainty. In addition, all of the above indicates that it is necessary to take into account the compliance of national and international regulatory acts when organizing international cargo transportation, which is the basis of the formation of the cargo transportation management system in international traffic.

CLARIFICATION OF COORDINATES WHEN SEARCHING FOR SEA MINES BY MEANS OF KINEMATIC DESIGN

2024-02-15T14:24:24+02:00

The issue of demining sea raids and ports, which is relevant for Europe during the period of active deployment of military confrontations on its territory, is considered. It is proposed to expand the search capabilities of trawler boats by adding auxiliary search vessels to them. This increases the effective search area by one and a half to two times, reducing by 25–30% fuel consumption for search passages of floating vehicles. The optimal trajectory of search movements of floating vehicles along the Archimedean spiral and the method of determining the coordinates of mines by means of kinematic design are proposed. The movement of search vessels along an Archimedean spiral is recommended due to the absence of sharp turns and reciprocating movements in such a trajectory, which are undesirable for the search movements of trawler boats. At the same time, the danger of having unlimited areas of the surface of the reservoir or the sea is also eliminated. As one of the most effective options for the disposal of mines, their detonation with warheads dropped from an aerial liquidator drone has been proposed. To clarify the coordinates of the location of anchor and bottom mines, it is proposed to use the kinematic design method. This technique provides for the formation of a base plane and the designation of a “picture” projection plane in the depth of the sea, on which the projecting rays will be projected. In this case, the wanted mine serves as a design object. The use of kinematic design techniques and an auxiliary floating search vessel to search for mines allows not only to carry out search operations without direct participation in the search of people, but also to increase the productivity and speed of search operations. In order to manage the movements of the search floats, to process the data provided by them about the detected mine, to specify the coordinates of the detected mine, a corresponding block diagram of the computer program is proposed. It was established that at speeds of 5÷5,5 knots of search movements of floating vessels, using the proposed search scheme, it is possible to survey up to 6 square kilometers of sea water area every hour. At the same time, it is possible to save up to 20 liters of valuable fuel during the survey of such an area due to the reduction of movements of the trawler boat.

EFFICIENCY OF THE “WATER – WATER” HEAT PUMP FOR HEAT SUPPLY OF MACHINE-BUILDING ENTERPRISES IN THE PRODUCTION OF CONSTRUCTION MATERIALS

2024-02-15T14:24:30+02:00

Introduction. The article examines the problem of using a water-to-water heat pump (water-to-water heat pump), which works on alternative energy sources for heat and hot water supply to buildings of engineering enterprises in the production of structural materials. TN “water – water” in its work can use the low-potential heat of water of rivers, lakes, and underground waters. Purpose. The purpose of the work is the thermodynamic substantiation and study of the expediency of using TN at machine-building enterprises in the production of structural materials. Results. An analysis of the thermodynamic characteristics of “water – water” TNs operating with a water source of low-potential heat was performed. The factors that affect the energy efficiency of “water – water” TN are determined, the peculiarities of water TN work for engineering enterprises in the production of structural materials are evaluated. In order to increase the thermodynamic efficiency of the heat supply system of machine-building enterprises in the production of structural materials, a scheme for extracting low-potential heat using the “water – water” TN is proposed. On the basis of the conducted research, it was established that the advantage of water as a heat carrier is that “water – water” TNs can work almost everywhere. Currently, a promising method of increasing the efficiency of the heat supply system of machine-building enterprises in the production of construction materials is the use of “water – water” TN during the annual cycle of its operation. Therefore, the water-to-water heat pump system provides high heat productivity throughout the year and has a higher energy efficiency index compared to traditional installations. TN “water – water” have a significant advantage over other thermal power plants. “Water – water” TNs consume energy from renewable sources, reduce electricity supply costs by more than half. Conclusions. The use of “water – water” TN for the utilization of low-potential heat energy of groundwater is economically beneficial, because the cost of heat supply by a heat pump is UAH 7 980 for a residential building with an area of 100 m2 per year. The analysis of the thermodynamic efficiency of heat supply systems shows that the use of a low-potential source of ground water heat has advantages over ground and air heat sources. In modern economic conditions, the trend of heat supply systems of machine-building enterprises in the production of structural materials can develop in the following directions: the use of vapor-compression TN “water – water”, which has a heat transformation coefficient of 3,15 and an exergy efficiency of TN of 32%, and the use of secondary energy resources of machine-building enterprises in the production of structural materials, as well as possible improvement of the thermal characteristics of machine-building buildings.

REVIEW AND ANALYSIS OF METHODS FOR ASSESSING DAMAGE TO STEEL STRUCTURES OF LIFTING MACHINES

2024-02-15T14:24:35+02:00

Introduction. In the ports of Ukraine, about 95 000 forklifts are operated, which are registered with the bodies of Derzhhirpromnadzor. In this, the majority of them (72%) developed their normative resource. The average term of their operation exceeds 30 years, and the degree of physical wear and tear approaches 90%. Replenishment of the VPM fleet is carried out mostly at the expense of equipment that was in operation, and the percentage of new equipment does not exceed 20%. It should also be noted that this situation is not the same in different ports of the country. Thus, in the Black Sea Sea Trade Port, the average service life of port transshipment equipment (PPT) is 40 years. At the same time, in the port of Pivdenny, it fluctuates and is no more than 20–30 years. Purpose. Taking into account the current situation, the problem of assessing the residual resource of PPT becomes urgent. It is also necessary to take into account that over-standard operation of VPM increases the amount of repair work and may pose an increased risk in the case of untimely or poor-quality repairs. Results. The problem related to the assessment of the residual resource by port transshipment equipment is considered. There are methods for determining damage to metal structures of cargolifting machines. Due to the predominance of disadvantages when using destructive control methods, non-destructive methods are increasingly being used today. They are more promising. The work considers the most used of them. Conclusions. There is no generally accepted approach to determining the damage of metal structures of LM today. At the same time, the existing methods have a number of significant drawbacks, which include the following: most methods are based on the application of destructive control, which entails the violation of the integrity of the examined metalwork, the need for subsequent repair of the element from which metal is extracted, resulting in additional costs of time and money; practically absent studies of the main steel grade (09Г2С), of which most of the load-bearing elements of steel structures of lifting machines are made. The most promising methods of damage assessment of LM metal structures are methods of nondestructive testing, in particular, the methods based on the assessment of the hardness parameters of the metal surface layer and coercive force.

MODERN SHIPS AND THE INTEGRATION OF DRONES – A NEW ERA FOR MARINE COMMUNICATION

2024-02-15T14:24:40+02:00

This article explores the changes that have occurred as a result of the integration of unmanned aerial vehicles (UAVs) into everyday maritime activities, with a particular focus on the potential of UAVs, or so-called drones, to solve existing problems and improve the productivity of maritime transport. This study initiates an in-depth study of the subject matter in order to provide valuable insight into the challenges associated with modern maritime communication. A proposal has been put forward to integrate drones into communications networks, arguing that such inclusion will increase their reliability and efficiency, especially in geographically isolated areas and adverse weather conditions. The idea has been rigorously tested and evaluated through a series of tests, including computer simulations, as well as field trials using a variety of ships and unmanned aerial vehicles. The results substantiate the proposed hypotheses, indicating a greater prevalence of open communication, increased implementation of preventive measures, and increased data collection. The use of unmanned aerial vehicles, for example, helps improve situational awareness among people, which is a critical factor in preventing maritime accidents. The use of unmanned aerial vehicles has made it easier to explore previously inaccessible areas, which has made it possible to carry out scientific activities in these places. The importance of this issue cannot be overstated, as it has significant implications for both human well-being and the preservation of the planet. The results of the study show that the integration of drones into maritime operations will provide a significant increase in operational efficiency, while contributing to the modernization of maritime communications and the creation of security protocols. In this article, we review the potential advantages and disadvantages of this new technological paradigm and suggest areas where further research is needed.

STUDY OF THERMAL CHARACTERISTICS OF THE GAS-POWDER FLOW USING THE GAS-FLAME METHOD OF RESTORATION OF WORKING SURFACES OF PARTS OF SHIP MACHINES AND MECHANISMS

2024-02-15T14:24:47+02:00

Introduction. In gas-flame spraying, the source of thermal energy is the flame formed as a result of burning a mixture of oxygen and combustible gas. Acetylene, propanebutane, hydrogen, natural gas and other gaseous hydrocarbons are used as fuel gas. One of the most important characteristics of a flame is its temperature, which depends on the ratio of oxidizer to combustible gas. The pulsating nature of the flame causes an uneven distribution of the density of the flow of powder particles and, therefore, their uneven heating. Therefore, the calculations of the thermal characteristics of the jet of heated gases and the temperature of the particles do not guarantee sufficient accuracy. To study heat exchange processes in a gas-powder jet, it is necessary to have data on heat flow density, enthalpy, viscosity, coefficients of thermal and thermal conductivity, which determine the conditions and intensity of the process. In connection with the above, the main attention in the work is given to the experimental determination of the thermal characteristics of the flame of the powder atomizer. Purpose. The purpose of the article is an experimental study of the processes of heat exchange of a gas-powder jet, which affects the conditions, quality and intensity of the process of restoration and strengthening of the working surfaces of parts of ship’s technical equipment in the process of restorative repair. Results. Based on the results of theoretical and experimental studies of the thermal parameters of the flame, it was established that the fields of temperature distribution and density of heat flows for acetylene-oxygen and propane-butane-oxygen flames were constructed. Conclusions. The study of the thermal characteristics of the flame in the process of restoration and strengthening of the surfaces of parts of ship’s technical equipment allows us to state that the degree of thermal activation of the sprayed material has the main effect on the density of the coatings and the strength of adhesion to the base. The distance from the nozzle section and the radius of the flame cross-section at which the value of the heat flux density and the temperature reach the maximum value are established. It is proved that the maximum values of the flux density and temperature shift to the flame axis, and the minimum values to the periphery.

IMPACT ASSESSMENT OF THE POWER AND SIZE PARAMETERS OF ULTRAVIOLET REACTORS ON THE PERFORMANCE OF BALLAST WATER TREATMENT SYSTEMS

2024-02-15T14:26:41+02:00

Introduction. The transfer of alien organisms and pathogenic microorganisms through ballast water during ballast intake and discharge operations on ships has a negative impact on the marine environment and human health. International standards established by the International Convention for the Control and Management of Ship’s Ballast Water and Sediments regulate the maximum amount of live organisms in ballast water, creating a need for the analysis and comparison of ballast water treatment system designs. Purpose. This article describes a study on the influence of the power and size parameters of ultraviolet reactors on the performance of ballast water treatment systems. Results. In the article analyzes the energy characteristics of existing ballast water treatment systems with ultraviolet disinfection stages from companies such as Alfa Laval, Desmi Ocean Guard, Hyundai Heavy Industries, Wartsila, Trojan Marinex, Optimarin, Norwegian Greentech are presented. Based on the obtained data, an evaluation of the impact of the power and size parameters of the ultraviolet reactor on the nominal performance of ballast water treatment systems was performed, and dependencies of power, weight, and capacity of the ultraviolet reactor on the maximum ballast flow rate were obtained. Conclusions. The results of this study will simplify the process of selecting ultraviolet reactors during the design of ballast water treatment systems, enable a comparison of the efficiency of the existing ultraviolet treatment stage relative to others, and the obtained dependencies can be useful in the design and modernization of ballast water treatment systems. They will allow for a more accurate calculation of the required power and size characteristics of the ultraviolet reactor depending on the expected system performance.

ANALYSIS OF THE ACCURACY OF DETERMINATION OF THE ENDURANCE LIMIT BY THE METHOD OF GRADUAL LOAD CHANGE

2024-02-15T14:27:22+02:00

Introduction. The problem associated with the accuracy of the experimental determination of the average probable value of the endurance limit and its root-meansquare deviation using the up-down method is considered. To solve the problem, an example was considered and calculations were carried out, which made it possible to plot the dependences of the errors of these fatigue resistance characteristics on the test modes. It was shown that the average probable values of endurance limits and their root-mean-square deviations significantly depend on both the initial load level and the voltage drop between levels. In this case, it was found by calculation that the minimum error values occur when the initial stress is close to the expected endurance limit, and the voltage drop d is minimal. Purpose of the article is to study the accuracy of the method for determining the endurance limit and its dispersion under different test planning options. Results. The dependences of the endurance limit and its root-mean-square deviation from the interval between stress levels and the initial load level are obtained by calculation, and the values of their errors are determined, presented in tabular and graphical forms. Conclusions. The average probable values of endurance limits and their root-mean-square deviations, determined by formulas (3) and (4), depend both on the initial load level and on the voltage drop between the levels. The minimum error values occur when the initial stress is close to the expected endurance limit, and the voltage drop is minimal. The errors of the root-mean-square deviation of the endurance limit vary within the limits, and their dependence on the voltage drop and the initial level is stochastic.

IMPROVEMENT OF THE FUEL COMBUSTION MODEL IN A DIGITAL TWIN APPLICATION FOR DIESEL ENGINES

2024-02-15T14:27:26+02:00

Introduction. The application of digital twins represents a promising solution for enhancing the efficiency of marine power installations, particularly their vital components – marine internal combustion engines (ICE). A digital twin, implemented on a dedicated server or as part of an engine monitoring system, is employed for automated data processing from sensors installed on the engine. It accumulates statistics, determines the current technical condition of the engine, assesses its operational efficiency, identifies potential malfunctions, and produces decision-making regarding modifications to operational programs. The key element of the digital twin is the mathematical model of the operating cycle of a marine diesel engine. This work focuses on a specific aspect of the performance type digital twin application developed for monitoring the technical condition and diagnosing faults in marine ICMEs, specifically addressing the synthesis of heat release characteristics within the engine cylinder. Purpose. The purpose of this study is to increase capabilities of the fuel combustion model applied for synthesizing heat release characteristics by considering the variable mean droplet diameter of the fuel spray during the injection process. This is crucial as the spray atomization conditions deteriorate at the beginning and end of the injection process. Results. As a result of the research, the mechanism of how the mean droplet diameter influences the interrelated processes of fuel evaporation and combustion is revealed. It is demonstrated that accounting for the variable nature of spray atomization significantly affects both the heat release processes and the formation of harmful substances. Conclusions. As the conclusion, incorporating the variable mean droplet diameter throughout the injection process allows for a more accurate representation of real operating processes, enhancing the adjustability and adaptability of the digital twin. However, complete utilizing the additional capabilities of the model requires the evaluation or measurement of fuel injection characteristics during engine operation, marking a prospect for future research.

ANALYSIS OF THE INFLUENCE OF THE LIMIT LEVELS OF VIBRATION ON THE RESIDUAL LIFE OF SHIP MACHINES AND MECHANISMS

2024-02-15T14:27:29+02:00

Introduction. The high efficiency of the transition to the system of maintenance of ship technological equipment based on the actual condition is based not only on reducing the terms and costs of maintenance, but also on the exclusion of unjustified repairs. This leads to an increase in the machine units’ reliability. The transfer of the ships of the Navy of Ukraine for maintenance and repair in their current condition requires the availability of diagnostic equipment for various machines and mechanisms of the ship on board. Purpose. To theoretically substantiate and experimentally verify the limit levels of vibration of ship machines and mechanisms with rotating rotors. The implementation of this goal involves solving the problem of finding the function between the limit levels of vibration and the "fatigue" of bearings for ship machines and mechanisms with rotating rotors and rolling bearings with a resource of 10–12 thousand hours. Results. A method of vibration diagnostics of the pumping unit is proposed, which does not require information about the vibration norms, their tactical and technical data, the state of the unit at the time of diagnosis, and is applicable, as the conducted studies have shown, to all types of pumps with an electric drive. Vibration surveys of ship machines and mechanisms carried out by the authors for 10 years, as well as the results of data analysis by other authors, allow us to state that during the operation of ship machines and mechanisms, it is advisable to conduct vibration surveys and, if necessary, rebalancing the rotors, at least once in 2–3 months. The operation of ship pumping units is accompanied by vibration, which negatively affects the resource of their work. The most loaded (from a mechanical point of view) are bearing units, which, as a rule, determine the ship machines and mechanisms service life. Conclusions. This approach makes it possible to develop simple diagnostic devices consisting of two or three channel spectrum analyzers, an arithmetic unit for calculation and a signaling unit, as well as an analysis unit in which automatic identification of vibration frequencies and diagnosis will be carried out. A special dependence was developed for the practical substantiation of the limit levels of vibrations of various ship machines and mechanisms. The method of determining the residual resource of ship machines and mechanisms in operational conditions is proposed. A promising further continuation in this direction is the detailing of the calculation of vibration norms for various types of ship machines and mechanisms, the development of methods for calculating and forecasting the residual resource, the instrument implementation of this approach.

STUDY OF TOWING RESISTANCE OF CRUISE SHIPS DURING THEIR DIMENSIONAL MODERNIZATION

2024-02-15T14:27:33+02:00

The growing demand for sea cruises forces shipping companies to start production of new ships. In addition, the growing requirements of the International Maritime Organization to ensure the safety of navigation and environmental protection force shipyards and manufacturers of ship equipment to involve the most modern developments in marine engineering and conduct relevant research and design companies. At the same time, there are several dozen ships in operation in the world passenger fleet, which must be brought up to modern requirements, that is, reduce the level of wear and tear and meet the requirements of the cruise market. The world cruise fleet has a significant number of such ships - candidates for dimensional modernization. The increase in the size of the ship due to the addition of a cylindrical insert will affect not only the ship’s hull, but also the operation of the propeller-steering system and the main engine, since it is an integral part of the entire ship’s power system. The interaction of the structural elements of the propulsive complex has a systemic nature and should be studied using a systemic approach. Such structural elements are the propeller-rudder complex, the hull, the main electric motor (ship electrical power system). An analysis of the effect of increasing the length of the ship on the characteristics of the system that forms the propulsive complex – “propellerhull – main engine – gun” was carried out. The assessment of the maneuverability and propulsive qualities of the vessel is based on the determination of its buckling resistance. The towing resistance as a function of the speed and length of the vessel (the length of the cylindrical insert) was studied using the Holtrop method. A qualitative and quantitative assessment of the towing-propulsion resistance and its components during dimensional modernization was carried out.

EMERGING TECHNOLOGIES AND APPLICATIONS OF WIRELESS POWER TRANSFER

2024-02-15T14:27:36+02:00

Wireless power transfer (WPT) has made significant progress in becoming a feasible option for several applications since its first development. The primary objective of this article has been on magnetic resonant coupling (MRC), which is a kind of wireless power transmission (WPT). MRC is particularly noteworthy because of its high transfer efficiency, ranging from 40 to 80%, and its ability to charge many devices from 1 to 50 cm. Magnetic Resonant Coupling (MRC) is an acronym that refers to a phenomenon in which magnetic fields are used to establish a coupling between two or more entities. The usefulness of wireless chargers is the topic of discussion in this article. Although wireless chargers are seen to have slower charging rates than cable chargers, it has been observed that wireless chargers play a part in the preservation of batteries by keeping the charge level within the range of 50 to 80% during the charging process. Notably, Qi 1.2 is a standardized specification that facilitates expedited charging at a maximum power output of 15 watts, specifically operating at 9 volts and 1.67 amps. In the realm of long-range wireless power transfer (WPT), using electromagnetic beams to transmit electricity over considerable distances, spanning hundreds of meters or even kilometers, presents a discernible prospect. The problem of misalignment in wireless power transfer (WPT) and a proposed solution, including using Force Sensitive Resistors (FSRs), are examined. This paper presents empirical evidence showcasing the enhanced efficiency of implementing these solutions. Consequently, it establishes a foundation for wireless power transfer (WPT) in electric vehicles (EVs), drones, and green cells. The use of this instrument greatly facilitates the development of Wireless Power Transfer (WPT) technology and its subsequent advancement.

PROSPECTS FOR RESTORING THE TRANSPORT AND LOGISTICS INFRASTRUCTURE OF AIRPORT COMPLEXES IN UKRAINE AND ENSURING THE EFFICIENCY OF ITS OPERATION

2024-02-15T14:27:40+02:00

Introduction. The full-scale russian military aggression had an extremely negative impact on the state of air transport and the transport and logistics infrastructure of airports in Ukraine, which makes the issue of restoring the operation of airport complexes and ensuring their efficiency in the post-war period relevant. Purpose. The purpose of the article is to identify possible prospects and reserves for the restoration of air transportation and the development of an organizational mechanism for ensuring the effective functioning of the transport and logistics infrastructure of airport complexes in Ukraine in the post-war period, using the example of the Kyiv International Airport. Methods. The following set of scientific methods was used in the study: analysis of scientific and technical literature, SWOT-analysis, structural analysis, systemic and synergetic approaches. Results. The article examines the nature and process of organizing the activities of the airport complex, the current state of the transport and logistics infrastructure of airports in Ukraine. On the example of the Kyiv International Airport, promising directions for ensuring the effective operation of the airport complex are determined, taking into account the peculiarities of the interaction of transport modes at airports as points for providing transport services on cargo flows processing. Schemes of interaction of transport modes during multimodal transportation of goods through the airport have been developed. Based on the results of technical and economic calculations, the expediency of increasing the throughput capacity of the cargo terminal of the Kyiv International Airport was substantiated. The application of SWOT-analysis made it possible to determine the factors of the internal and external environment and to develop priority directions for the restoration of the transport and logistics infrastructure of airport complexes during the war period to ensure their effective functioning after the war. Scientific novelty. Prospective directions for ensuring the effective operation of the airport complex have been determined, taking into account the peculiarities of the interaction of transport modes at airports, schemes for interaction of transport modes during multimodal transportation of goods through the airport have been developed. Conclusions. Practical significance. On the basis of technical and economic calculations, it is proposed to increase the throughput capacity of the cargo terminal of the Kyiv International Airport and priority directions for the restoration of the transport and logistics infrastructure of airport complexes are determined.