International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

This paper presents an analysis and comparison of three steam turbines and its cylinders: from the conventional steam power plant, from nuclear power plant and from the marine propulsion plant. The best parameters for the comparison of whole turbines and its cylinders are: energy loss per unit of produced mechanical power, exergy destruction per unit of produced mechanical power, energy efficiency and exergy efficiency. Steam turbine from marine propulsion plant shows the worst performance, regardless if observing each cylinder or the whole turbine – it has the highest losses per unit of produced mechanical power and the lowest efficiencies (both energy and exergy). Such results can be explained by a fact that marine steam turbine must be much more dynamic in operation in comparison to other two turbines. Also, marine steam turbine analyzed in this paper did not possess steam reheating between the cylinders as the other two observed steam turbines, what has a dominant impact on the obtained results.

This paper presents numerical analysis of efficiencies and non-measured operating parameters for the marine two-stroke slow speed turbocharged diesel engine 6S50MC MAN B&W with direct fuel injection. Numerical analysis was based on a measurement set performed at different engine loads. Calculated efficiencies were mechanical, indicated and effective efficiency, while the calculated important operating parameters were power of engine mechanical losses, mean effective pressure, effective engine torque and specific effective fuel consumption. Engine load was presented in percentage of maximum continuous rating (MCR). The highest engine mechanical efficiency of 94.52 % was obtained at the highest engine load, while the highest engine effective efficiency of 49.34 % was obtained at the engine load 75 % of MCR. Available engine effective torque was from 267380 Nm on the lowest up to 643594 Nm on the highest engine load, while effective fuel consumption was between 171.18 g/kWh and 186.83 g/kWh.