Main directions and prospects for the development of marine twostroke cross-head low-speed engines

Low Low-speed two-stroke cross-head engines remain dominant among the power units that provide propulsion for large-capacity merchant vessels. This article examines the main directions and prospects for improving marine two-stroke low-speed engines. Based on the consideration of general design principles, the primary areas of focus are fuel efficiency, environmental safety, and operational reliability. Despite the high thermodynamic efficiency of the engine cycle, there remain reserves for further reducing specific fuel consumption by minimizing internal losses and maximizing the utilization of exhaust gas energy. The study addresses environmental aspects of marine diesel power plants based on low-speed engines and outlines the prospects for various technologies to comply with current regulations on limiting harmful emissions from exhaust gases. Key areas of development for reducing nitrogen oxide emissions include direct control of in-cylinder combustion processes, exhaust gas recirculation, and selective catalytic reduction. The potential of specific methods for decreasing sulfur and particulate matter emissions is also discussed. Particular attention is given to reducing greenhouse gas emissions, with the use of alternative fuels such as natural gas, methanol, and ammonia highlighted as promising solutions in the foreseeable future. The article further emphasizes the importance of operational reliability, identifying the monitoring of the technical condition of the power plant as the most effective approach. Overall, the paper provides an integrated perspective on improving the performance, safety, and sustainability of marine two-stroke low-speed engines, highlighting technological trends and practical solutions for decarbonization, emission control, and enhanced reliability of large- scale marine propulsion systems.

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