Transport development

DEVELOPMENT OF UKRAINIAN AUTOMOTIVE SMALL-DISPLACEMENT DIESEL ENGINE: 30 YEARS OF EVOLUTION FROM MOTORCYCLE TO BUS ENGINE

O.V. Grytsyuk, O.O. Sulyma — Thu, 30 Oct 2025 00:00:00 +0200

Introduction. Thirty years of experience represents a true treasure trove of knowledge for any subsector of mechanical engineering, including engine manufacturing. The modular series of small-displacement inline automotive diesel engines ranging from one to six cylinders, with the currently most popular displacement of 0.5 dm³ per cylinder, has been developed by the Kharkiv Design Bureau for Engine Manufacturing for 30 years, effectively laying the foundation for this design parameter. The past three decades have become a true forge of competencies for Ukraine’s diesel engine industry, which had never previously had experience in developing small-displacement automotive diesel engines for either commercial or specialized vehicles. Providing readers with answers to questions regarding the well-developed profile of domestic automotive diesel engines, the manufacturing of specific batches of various domestic engine brands, and conducting their testing as part of specific vehicles became the objective of the authors of this article. Objective. This article aims to systematize the experience gained over 30 years in designing a modular series of domestic automotive small-displacement diesel engines for knowledge transfer to the next generation of engineers. Results. It has been determined that the domestic automotive small-displacement diesel engines developed over 30 years and tested in four-wheeled motorcycles and automobiles have six different profiles: DT, DTN, DTA, DTNA, DTNA1, and DTNA2. However, DTNA1 profile diesels were identified as more promising for the future. Therefore, these engines were thoroughly and adequately developed, including during operation directly in their application objects. Particular attention was focused on the definitive testing of the 4DTNA1 automotive diesel engine as part of the RUTA-25d bus and official preliminary testing of the modernized MA33 vehicle, also equipped with the 4DTNA1 diesel engine. Conclusions. It has been determined that currently, the development of smalldisplacement domestic automotive diesel engines with the DTNA1 profile is most justified as a technological experience and competency development. The most promising niches for applying diesel engines of this profile brand are specialized equipment, military applications, and markets with less stringent environmental requirements, where simplicity and reliability are more important than maximum efficiency.

OPTIMIZATION OF ENERGY EFFICIENCY AND RISK ASSESSMENT FOR ITS IMPLEMENTATION IN MARINE MULTIMODAL ECO-ORIENTED TRANSPORTATION

A.M. Ibrahim, K.M. Klevtsov — Thu, 30 Oct 2025 00:00:00 +0200

Introduction. The article addresses the urgent issue of energy efficiency optimization in maritime multimodal transportation amidst current environmental and economic challenges. Facing stricter IMO emission requirements and rising fuel costs, shipowners need not only new technologies but also reliable tools to assess the risks of their implementation. The article focuses on a methodological approach to making well-founded managerial decisions. Aims. The article aims to substantiate the use of SWOT analysis as a methodological tool for the analytical assessment of risks and opportunities when implementing energy-saving technologies. The feasibility of using fuel additives is examined as a case study to test this method – a technologically accessible measure, the effectiveness of which, however, depends on many factors and requires a comprehensive pre-implementation analysis. Results. The article focuses on a practical decision-making tool – SWOT analysis. It is demonstrated that this method allows for a comprehensive assessment of the strengths and weaknesses of using fuel additives (e.g., fuel savings vs. additive costs), as well as external opportunities and threats (stricter environmental regulations vs. the emergence of low-quality products). To enhance objectivity, a quantitative interpretation of the analysis was performed, yielding an overall positive rating of 0.158, which indicates the viability of implementing the technology under the considered conditions. Conclusions. The proposed approach complements existing methods for assessing energy efficiency by providing shipowners with a structured tool for making informed decisions under conditions of multifactorial uncertainty. It has been proven that SWOT analysis is an effective means for evaluating operational, economic, and environmental risks, fully aligning with modern management requirements in maritime transport and applicable to the analysis of other innovative technologies.

RESULTS OF AN EXPERIMENT TO DETERMINE THE RANGE OF SOUND PROPAGATION IN THE SHELF ZONE OF THE BLACK SEA

M.B. Kapochkina, N.V. Kucherenko — Thu, 30 Oct 2025 00:00:00 +0200

The sound propagation range in the oceans and seas is the most important hydroacoustic characteristic, on which the efficiency of noise-scattering, sonar, density of network hydroacoustic systems of the information layer (positioning and communication) of the automated ship identification system depends. Two methodological (theoretical) aspects of determining the sound propagation range are considered. The first aspect is the determination of the sound propagation range as a function that depends on the frequency of the acoustic wave. The second is the determination of the propagation range of acoustic waves of different lengths as a constant of the number of cycles (wavelengths). For shallow water conditions, the propagation range of acoustic waves is additionally subject to significant dependence on such hydroacoustic characteristics of soils as quantitative indicators of sound reflection and absorption, as well as on the indicator of sound scattering by the sea surface. Obtaining an estimate of the sound propagation range in shallow water has an exclusively experimental solution. For depths of 10–20 m, such an estimate was obtained. At depths of more than 50 m, where an underwater sound channel may exist, the propagation range of acoustic waves can be determined by theoretical methods. The paper presents the results of experimental determination of the propagation range of sound at depths from 20 m to the depths of possible formation of a waveguide. The experiment was performed for the hertz frequency range, which, according to the theory of the propagation range of acoustic waves of different lengths, as a constant of the number of cycles (wavelengths), provides the maximum range of underwater sound communication, sonar and noise direction finding. Data processing of the hydroacoustic experiment to determine the propagation range of sound involves taking into account the refraction of acoustic waves, which forms acoustic shadow zones. To determine the propagation range of sound, it is proposed to determine the acoustic signature (amplitude spectrum), averaged over a certain time, with subsequent detection of the amplitudes of test frequencies as indicators of the intensity of the acoustic signal.

CONCEPTUALIZATION OF SITUATIONAL PL (PARTY LOGISTICS) IDENTIFICATION OF TRANSPORT SERVICE PROVIDERS

О.V. Kyryllova, V.Yu. Kyryllova — Thu, 30 Oct 2025 00:00:00 +0200

Introduction. The traditional practice of classifying transport service providers based on the Party Logistics (PL) model is rooted in a fixed typology of companies along a scale from 1PL to 5PL, which often fails to reflect the true functional roles they play in specific project or contractual interactions. This leads to methodological inconsistencies, analytical ambiguity, and the risk of pseudo-scientific interpretations of PL levels. The purpose of this study is to develop the theoretical and methodological foundations, as well as practical tools for situational identification of transport service providers within the PL model, taking into account the dynamics of their functional roles within specific client interactions. To achieve this goal, the article is logically and sequentially structured: from formulating an alternative scientific paradigm that views the PL level as a situational functional role of transport service providers, to the concept of situational PL identification as a tool for implementing this paradigm, and a conceptual model that defines its principles, criteria, and evaluation logic; concluding with the justification of an appropriate analytical tool for the practical implementation of the model in transport service management. Results. The study formulates a new paradigm that contrasts functional PL identification of transport service providers with the formal «labeling» of these companies within simplified classifications. The concept of situational PL identification is proposed, based on defining the service role of the provider depending on the level of integration, digital engagement, management participation, and the distribution of responsibility within a specific client interaction. An analytical evaluation methodology is developed, which includes: a Likert scale for collecting qualitatively qualified expert evaluations; the Analytic Hierarchy Process (AHP) for determining the weight coefficients of evaluation criteria; fuzzy logic tools for processing vagueness and uncertainty in expert judgments. Scientific novelty. The scientific novelty of the research lies in: formulating a conceptual approach to PL identification of transport service providers based on the context-dependent functional role of a company within the supply chain; justifying a new scientific paradigm of situational PL identification, which contrasts with the widespread practice of declarative marketing positioning (especially among transport and freight forwarding companies) within a fixed PL hierarchy; developing the concept of situational PL identification as a tool for implementing this paradigm, ensuring an objective determination of the company’s level of integration into the supply chain structure of a specific client; forming a comprehensive analytical toolkit for the situational PL identification task, which combines qualitative expert assessments (Likert scale), weighted criterion structuring (AHP method), and uncertainty processing using fuzzy logic. Practical value. The practical value lies in creating a universal tool for the systematic positioning of transport service providers in supply chains–taking into account actual functions performed, integration depth, and digital maturity. This allows for the avoidance of erroneous or marketing-driven assessments. Conclusions. The proposed approach provides more accurate identification of the level of service integration of transport service providers in the context of a dynamic market, minimizes the risks of incorrect positioning, and can be useful for both service clients and analysts, consultants, and strategists involved in the evaluation of supply chain participants.

MAINTAINING THE ENVIRONMENTAL FRIENDLINESS OF SEAGOING VESSELS WHEN USING CATALYTIC REDUCTION SYSTEMS FOR MARINE DIESEL ENGINES

O.A. Kuropyatnyk — Thu, 30 Oct 2025 00:00:00 +0200

Introduction. Operation of sea transport vessels is inextricably linked with the emission of harmful substances into the atmosphere, which are formed in the diesel engine cylinder during fuel combustion. One of the most dangerous of them is nitrogen oxides, the emission of which is regulated by MARPOL requirements. The most effective purification of exhaust gases from nitrogen oxides is provided by catalytic reduction systems. At the same time, due to the use of urea as a reagent in these systems, carbon dioxide emissions increase. This, due to the increase in the greenhouse effect, contributes to global warming. The purpose of the study is to determine the optimal operating modes of the ship’s catalytic reduction system for marine diesel engines. The optimal ones are understood to be those that ensure a minimal increase in carbon dioxide emissions while maintaining a high level of reduction in nitrogen oxide emissions. Results. The studies were carried out on a Gas Carrier class vessel with a displacement of 127,645 tons with two main engines 5X72DF Hyundai-WinGD and three auxiliary engines 6H35DF Hyundai-HiMSEN, the exhaust gases of which were subjected to catalytic reduction. Optimal modes have been experimentally established, in which the relative increase in carbon dioxide emissions does not exceed 2.3% for both types of diesel engines. Nitrogen oxide emissions for 5X72DF Hyundai-WinGD diesel engines do not exceed 3.3 g/(kW · h) and do not exceed 2.4 g/(kW · h) for 6H35DF Hyundai-HiMSEN diesel engines, which meets the requirements of Annex VI of MARPOL. The relative reduction in nitrogen oxide emissions in these modes is 66.7–83.4% for the 5X72DF Hyundai-WinGD diesel engine and 60.8–78.3% for the 6H35DF Hyundai-HiMSEN diesel engine. Conclusions. Catalytic reduction systems for marine diesel engines are characterized by the presence of optimal operating modes. It is in these modes that the minimum increase in carbon dioxide emissions is ensured while maintaining a high level of reduction in nitrogen oxide emissions. The coincidence of the values obtained for the low-speed diesel engine 5X72DF Hyundai-WinGD and the medium-speed diesel engine 6H35DF Hyundai- HiMSEN indicates the correctness of the research and the possibility of implementing their results on all types of diesel engines and catalytic reduction systems.

USING A LOW-PRESSURE EXHAUST GAS RECIRCULATION SYSTEM TO ENSURE THE ENVIRONMENTAL PERFORMANCE OF MARINE DIESEL ENGINES

S.V. Sagin, O.A. Kuropyatnyk — Thu, 30 Oct 2025 00:00:00 +0200

Introduction. The efficiency of operation of sea and inland waterway vessels is determined not only by obtaining economic profit from transporting goods or providing recreation for passengers, but also by the level of negative impact of vessels and their power plants on the environment. One of the most polluting components that enter the environment from thermal engines of ship power plants is exhaust gases. The exhaust gases of ship diesel engines, along with neutral and hazardous components, include toxic substances, including nitrogen oxides, the emission of which is regulated in accordance with the requirements of Annex VI of MARPOL. In order to reduce the emission of nitrogen oxides, various methods are used, the most common of which is exhaust gas recirculation. The purpose of the study was to determine the impact of exhaust gas recirculation on the environmental performance of ship diesel engines. Results. To consider the issue of ensuring the environmental performance of ship diesel engines by using low-pressure exhaust gas recirculation systems. The features of lowpressure exhaust gas recirculation systems installed on high-power low-speed marine diesel engines are highlighted. It is in these systems that some of the exhaust gases after the gas turbocharger are returned to the cylinder of the marine diesel engine, thereby contributing to a decrease in temperature during fuel combustion. The results of research carried out on a low-speed marine diesel engine 7UEC60LS from Mitsubishi, equipped with a low-pressure exhaust gas recirculation system with a recirculation degree of 5…20 %, are presented. The influence of the recirculation degree on the emission of nitrogen oxides and the temperature of diesel exhaust gases was determined. Conclusions. It was experimentally established that changing the degree of exhaust gas recirculation in the range of 5…20 % provides a decrease in the concentration of nitrogen oxides in exhaust gases by 3.8…30.7 %, respectively, depending on the load of the diesel engine. It was also found that the use of a low-pressure exhaust gas recirculation system leads to an increase in temperature loads on the cylinder group and exhaust system of a marine diesel engine.

FLEET OPTIMIZATION AND ITS DISTRIBUTION ON THE LINES UNDER CONTAINER FLOWS UNCERTAINTY

S.P. Onyshchenko, O.M. Melnyk, O.L. Drozhzhyn, Y.A. Bondarenko — Thu, 30 Oct 2025 00:00:00 +0200

Introduction. Planning the fleet composition, which corresponds to the goals and competitiveness of the carrier company, as well as modern trends in the container transportation market, is based on the study of container flows, taking into account their uncertainty. This forms the information basis for making decisions regarding the structure of the fleet and its operation. These decisions also involve considering the feasibility of operating liner services in general and assigning vessels to them, in particular. Results. A mathematical model for the strategic management level is proposed, where the period of time under consideration is a year or more. The fleet includes both own and timecharter vessels, so the model variables reflect the relevant conditions – which vessel or vessels operate on a certain line, both own and leased vessels. The target function of the model is the total profit from the operation of vessels, which takes into account, in addition to the profit from the operation of own and leased vessels on the lines, also the profit from own vessels that are proposed to be leased on time-charter, taking into account economic feasibility. The model limitations take into account: ensuring the volume of transportation in the range from pessimistic to optimistic levels between the ports of the lines; the permissible number of vessels leased on time-charter; ensuring a certain level of efficiency of each vessel on the lines. The optimization results provide the fleet composition and distribution of vessels on the lines. Conclusions. The proposed mathematical model for optimizing the fleet composition and its distribution on the lines is reliable, taking into account the compliance of the results with the input data and the adequate response of the results to changes in the input data. This model, as a development of existing models, does not contradict the results of previous studies that created an appropriate theoretical basis for the specified development, which also confirms its reliability. The optimization results form a basis for decision-making, allowing for “what-if” experiments with the level of freight rates, operational costs of vessels, work volumes, the cost of time charter, etc.

DIGITAL TECHNOLOGIES IN THE LIFECYCLE MANAGEMENT OF RAILWAY ROLLING STOCK: ANALYTICAL OVERVIEW AND DEVELOPMENT PATHS

D.I. Skurikhin, A.O. Lovska, V.H. Ravlyuk, A.V. Rybіn — Thu, 30 Oct 2025 00:00:00 +0200

Introduction. Numerous scientific publications emphasize the importance of integrating modern digital technologies into the management of technical systems, particularly in the railway sector. However, the specifics of the railway rolling stock lifecycle require a comprehensive approach that combines engineering solutions, information technologies, organizational processes, and safety requirements. Recent literature increasingly addresses the need to adapt such integrated models to discrete manufacturing industries with a high level of regulation, such as railcar production. Purpose. This article expands the analysis of integrated lifecycle management technologies for railway rolling stock, covering all stages from design to disposal. The objective is to systematize current digital tools, evaluate their impact on efficiency, safety, and process transparency, and identify directions for adaptation in countries with transition economies. Results. A wide range of technologies used at each lifecycle stage of railcars has been analyzed. The design stage relies on PLM systems, CAD/CAE platforms, and simulation tools for loads and lifecycle assessment. The manufacturing stage is supported by MES, ERP, RFID/Barcode systems, additive manufacturing, and AI-based quality control, with real-world examples from SNCF, Alstom, and CAF. The operation stage incorporates IoT sensors, digital twins, telematics, fleet management, and big data analytics. Predictive maintenance is enabled through AI, smart contracts, and blockchain-based service history records. Modernization involves PLM integration, 3D scanning, obsolescence management, and strategic replacement of components. The final stage – disposal and recycling – is supported by life cycle assessment, material tracking, and recyclability metrics. Special focus is given to cloud-based blockchain infrastructure and smart contracts that connect all lifecycle phases into a single trusted digital environment. Conclusions. This study demonstrates that integrated lifecycle management of railway rolling stock is essential for increasing efficiency, safety, and service life. Digital technologies enable cost reduction, faster production and maintenance cycles, and complete component traceability. Further research should focus on the localization of Smart MES systems, blockchain integration in maintenance workflows, and the creation of digital component archives for effective modernization. The paper also highlights the need to standardize data management practices and adapt global solutions to the specific context of railcar manufacturing in transition economies.