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

In the presented paper are performed energy and exergy analyses as well as a comparison of two similar steam turbines from conventional power plants. The first turbine is from an older, while the second turbine is from newer steam power plant. The dominant mechanical power producer in an older steam turbine is LPC (which produces mechanical power of almost 66 MW), while in a newer steam turbine the dominant mechanical power producer is IPC which produces power equal to 102.4 MW. Whole older steam turbine has higher energy and exergy loss in comparison to the whole newer steam turbine. Whole turbine from the newer power plant has much higher energy and exergy efficiencies in comparison to whole turbine from an older power plant. In an older steam turbine, LPC did not show the expected performance because its exergy efficiency is very low (equal to 75.49%), what is much lower than in any other cylinder from both observed turbines. The ambient temperature change sensitivity of the two observed steam turbines and their cylinders is reverse proportional to efficiencies (both energy and exergy). Steam turbine from an older power plant is much more sensitive to the ambient temperature change.

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.