Abstract
The current state and ways for improving the effectiveness of steam turbine units at nuclear power stations (NPS) are examined. The specifics of NPS turbines is described. The comparison of NPS steam turbine performance with the performance of steam turbines at thermal power stations (TPS) demonstrates that power units of NPSs are much poorer in effectiveness due to relatively low steam conditions at the inlet and the presence of wet steam already in the first stages of turbines. A decrease in the relative internal efficiency of NPS turbines results from the enhanced negative effect of wetness in the expansion process: in modern NPS turbines, more than two-thirds of the heat drop is spent in the two-phase region, while less than one fourth in TPS turbines. It is demonstrated that the effectiveness of NPS steam turbine units can be increased drastically in the future only through a considerable rise in the turbine inlet steam conditions. This can be achieved by using a heat carrier at supercritical conditions in the NPS reactor. The dependence of the effectiveness of NPS modern turbines on the turbine inlet steam conditions in the applicable pressure ranges of the saturated steam and vacuum in the condenser, as well as on the turbine exhaust area, is examined. For a 1000 MW turbine, increasing the inlet pressure from 6.0 to 8.0 MPa raises the turbine power and efficiency by 3.5%. At a condensing turbine outlet pressure ranging from 2.5 to 7.5 kPa and a constant velocity downstream of the last stage, the turbine power and efficiency can be increased by 7%. The importance of the exhaust area for the turbine effectiveness is revealed. Alternative designs of the flowpath in a low-pressure cylinder are analyzed. A unique configuration of a steam turbine unit with two-stage moisture separation is proposed. The comparison of high-speed turbines with low-speed ones was performed. It is demonstrated that the efficiency of the examined turbines is nearly the same within the accuracy of design calculations and the test results, and it is slightly higher for low-speed turbines due to lower losses with outlet velocity.
Similar content being viewed by others
References
A. R. Avetisyan, A. F. Pashchenko, F. F. Pashchenko, G. A. Pikina, and G. A. Filippov, Thermal-Hudraulic Models of Power Plant Equipment, Ed. by G. A. Filippova and F. F. Pashchenko (Fizmatlit, Moscow, 2014) [in Russian].
G. A. Filippov, V. G. Gribin, A. A. Tishchenko, and A. S. Lisyanskii, “The effect of humidity on the efficiency of steam turbines,” Izv. Ross. Akad. Nauk Energ., No. 6, 96–107 (2012).
G. A. Filippov, O. I. Nazarov, and L. A. Belyaev, “Ways of improvement of steam turbine units,” Izv. Tomsk. Politekh. Univ. 320 (4), 5–9 (2012).
Yu. K. Petrenya, L. A. Khomenyuk, I. A. Kovalev, and Yu. A. Kachuriner, “Prospects for the development of high-speed steam-turbine installations for nuclear power-generating units with a capacity of 1500 MW and higher,” Therm. Eng. 50, 112–119 (2003).
G. A. Filippov, V. G. Gribin, A. A. Tishchenko, V. A. Tishchenko, and I. Yu. Gavrilov, “Experimental study of the effect of the initial humidity on parameter distribution of erosion-hazardous liquid phase behind the nozzle grating,” Vestn. MEI, No. 1, 55–61 (2013).
G. A. Filippov, V. G. Gribin, and A. A. Tichenko, “Experimental studies of wet-steam polydisperse flows in turbine blade cascade,” in Proc. Conf. the Science and Engineering of Non-Equlibrium Wet Steam Flows in Steam Turbines, Cambridge, Sept. 10–11, 2012.
G. A. Filippov, A. S. Lisyanskii, O. I. Nazarov, and Yu. P. Tomkov, “Direction of improvement of highspeed steam turbines of NPPs,” Energ. Mash. Ustanovki, No. 3, 3–12 (2008).
V. V. Nedavnii and A. S. Laskin, “Possibilities for creating high-power steam turbines with reduced overall dimensions,” Energetik, No. 8, 48–51 (2014).
G. A. Filippov, A. S. Lisyanskii, O. I. Nazarov, and Yu. P. Tomkov, “Direction of improvement of highspeed steam turbines of NPPs,” Energ. Mash. Ustanovki, No. 3, 3–12 (2008).
A. G. Kostyuk, V. V. Frolov, A. E. Bulkin, and A. D. Trukhnii, Steam and Gas Turbines for Power Plants Mosk. Energ. Inst., Moscow, 2008).
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © G.A. Filippov, E.B. Yurchevskii, 2018, published in Teploenergetika.
The company’s name is according to its statutory documents.
Rights and permissions
About this article
Cite this article
Filippov, G.A., Yurchevskii, E.B. Ways for Improving Efficiency and Reliability of Steam Turbines at Nuclear Power Stations. Therm. Eng. 65, 581–588 (2018). https://doi.org/10.1134/S0040601518090033
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S0040601518090033