The results of the research work on biofuel’s impact on the environmental and economic performance of marine diesel engines are presented. During the research, a fuel mixture was used that consisted of the diesel fuel RMA10 and FAME biofuel. The objective of the research was to determine the optimal concentration of biofuel mixed with diesel fuel. The research work was carried out on three of the same type of marine medium-speed diesel engine, 6N165LW Yanmar. One of the diesel engines only operated on diesel fuel, and the other two operated on a mixture of diesel fuel and 5–20% biofuel. During the experiment, the diesel engines operated at a load of 50–80% of the rated value. Experimentally, it was found that using biofuel improved the environmental friendliness of diesel engines: the emission of nitrogen oxides in exhaust gases was reduced by 8.7–23.4%, and the emission of carbon oxides in exhaust gases was reduced by 3.1–24%. However, when using biofuel, the economic efficiency of diesel operation decreased as the specific effective fuel consumption increased by 0.5–9.3%. The highest environmental efficiency was achieved when using a fuel mixture that included 10–15% biofuel in an 80% diesel load. In this case, the emission of nitrogen oxides was reduced by 21–23.5%, the emission of carbon oxides was reduced by 16.5–19.2%, and the magnification of the specific useful consumption of the diesel engine was 1–1.55%.

This paper aims to consider the issue of increasing the environmental friendliness of shipping by using alternative fuels in marine diesel engines. It has been determined that marine diesel engines are not only the main heat engines used on ships of sea and inland waterway transport, but are also sources of emissions of toxic components with exhaust gases. The main compounds whose emissions are controlled and regulated by international organizations are sulfur oxides (SO_X) and nitrogen oxides (NO_X), as well as carbon dioxide (CO₂). Reducing NO_X and CO₂ emissions while simultaneously increasing the environmental friendliness of shipping is possible by using fuel mixtures in marine diesel engines that include biodiesel fuel. During the research carried out on Wartsila 6L32 marine diesel engines (Shanghai Wartsila Qiyao Diesel Co. Ltd., Shanghai, China), RMG500 and DMA10 petroleum fuels were used, as well as their mixtures with biodiesel fuel FAME. It was found that when using mixtures containing 10–30% of FAME biodiesel, NO_X emissions are reduced by 11.20–27.10%; under the same conditions, CO₂ emissions are reduced by 5.31–19.47%. The use of alternative fuels in marine diesel engines (one of which is biodiesel and fuel mixtures containing it) is one of the ways to increase the level of environmental sustainability of seagoing vessels and promote ecological shipping. This is of particular relevance when operating vessels in special ecological areas of the World Ocean. The relatively low energy intensity of the method of creating and using such fuel mixtures contributes to the spread of its use on many means of maritime transport.

Operability and efficiency of transport diesel engines significantly depend on periodical diagnosis of its technical condition. The article considers the features of monitoring and diagnostic of transport diesel engines with the help of vibroacoustic analysis of high pressure fuel equipment and gas distribution mechanism. Functional scheme of diagnostic system and analytical method of TDC determination is described. Article gives an example of four-stroke and two-stroke diesel engines diagnosis. Also the article shows turbocharger speed determination and diagnosis with the help of vibroacoustic spectrum analysis. The main feature of the given methods is their high efficiency for diagnosis of transport diesel engines during operation.

This paper discusses the use of additional ultrasonic fuel treatment technology to reduce sulfur oxide emissions from marine diesel exhaust gases. The research was conducted on a Bulk Carrier vessel with a deadweight of 64,710 tons with the main engine YMD MAN BW 6S50ME-C9.7 and three auxiliary diesel generators CMP-MAN 5L23/30H. The exhaust gases from all engines were treated for sulfur impurities using a scrubber system. It was stated that the combined use of the exhaust gas scrubber system and ultrasonic fuel treatment technology (compared to scrubber-only exhaust gas cleaning) results in a reduction in carbon dioxide CO₂ and sulfur dioxide SO₂ emissions, along with their ratio SO₂/CO₂. The additional ultrasonic fuel treatment technology has had the most significant effect on sulfur-containing components, leading to a substantial decrease in SO₂ emissions from exhaust gases. For various operating conditions of ship diesel engines, a reduction in CO₂ emissions of 2.9–7.5% and a reduction in SO₂ emissions of 9.3–33.1% were established. This achieved a reduction of 6.3 to 23.7% in the SO₂/CO₂ ratio, a critical parameter for evaluating the performance of the scrubber system in exhaust gas cleaning, as mandated by the provisions of Annex VI of MARPOL. The requirements of the international conventions MARPOL and SOLAS were adhered to during the experiments.

Introduction. The significant dynamic nature of modern geopolitical and military threats sets new requirements for evaluating the criteria effectiveness of solving maritime industry management problems, requires new methodological approaches and mathematical models for evaluating criteria, and determines a new architecture of information systems in the structure of which these approaches and models are implemented. This makes the issue of the analysis of the application of criteria and the development, research, and implementation of such models and systems extremely relevant. Aim and tasks. The purpose of the study is to create a methodological approach to evaluating the criteria that characterize the effectiveness of the management of the maritime industry, with the dynamic change of criteria due to the influence of threats and challenges. Results. A methodological approach has been developed to evaluate the criteria that characterize the effectiveness of the management of the maritime industry based on the model for assessing the convergence of the absolute values of the first derivatives of the criteria over time, which, at short time intervals, can be considered as criteria change trends. It has been established that instead of reducing transportation costs, management switches to the principle of ensuring optimal costs, which leads to an increase in the cost of freight and shock reactions in the sea transportation market. It was established that it is advisable to use the LSCI criterion as an indicator of the negative effect of “local optimization”. After determining the development trends of the criteria, their evaluation as well as the assessment of their convergence were carried out, which became the basis for proposing directions for improving the efficiency of maritime industry management. Conclusions. The developed methodological approach and the mathematical model of its implementation make it possible to conduct both quantitative and qualitative analyses of the effectiveness of management of the maritime industry. To increase the efficiency of management, it is proposed: to integrate port community systems; to increase the stability of the port infrastructure so that it can function in crisis conditions; to achieve coordination of management actions at all levels; to avoid “local optimization” and introduce integral optimization; to respond not only to direct threats but also to detect the cascading effects of threats.