The Efficiency Increase of the Steam Turbine Low Pressure Cylinder Last Stage by the Blades Spatial Profiling

DOI https://doi.org/10.15407/pmach2020.01.006
Journal Journal of Mechanical Engineering – Problemy Mashynobuduvannia
Publisher A. Podgorny Institute for Mechanical Engineering Problems
National Academy of Science of Ukraine
ISSN 0131-2928 (Print), 2411-0779 (Online)
Issue Vol. 23, no. 1, 2020 (March)
Pages 6-14
Cited by J. of Mech. Eng., 2020, vol. 23, no. 1, pp. 6-14

 

Authors

Andrii V. Rusanov, A. Podgorny Institute of Mechanical Engineering Problems of NASU (2/10, Pozharskyi St., Kharkiv, 61046, Ukraine), e-mail: rusanov@ipmach.kharkov.ua, ORCID: 000-0003-1345-7010

Viktor L. Shvetsov, Joint-Stock Company Turboatom (199, Moskovskyi Ave., Kharkiv, 61037, Ukraine), e-mail: shvetsov@turboatom.com.ua ORCID: 0000-0002-2384-1780

Svitlana V. Alyokhina, A. Podgorny Institute of Mechanical Engineering Problems of NASU (2/10, Pozharskyi St., Kharkiv, 61046, Ukraine), V. N. Karazin Kharkiv National University, (4, Svobody Sq., Kharkiv, 61022, Ukraine), e-mail: alyokhina@ipmach.kharkov.ua, ORCID: 0000-0002-2967-0150

Natalia V. Pashchenko, A. Podgorny Institute of Mechanical Engineering Problems of NASU, (2/10, Pozharskyi St., Kharkiv, 61046, Ukraine), e-mail: nata_y@ukr.net, ORCID: 0000-0002-3936-7331

Roman A. Rusanov, A. Podgorny Institute of Mechanical Engineering Problems of NASU (2/10, Pozharskyi St., Kharkiv, 61046, Ukraine), e-mail: roman_rusanov@ipmach.kharkov.ua, ORCID: 0000-0003-2930-2574

Mykhailo H. Ishchenko, Joint-Stock Company Turboatom (199, Moskovskyi Ave., Kharkiv, 61037, Ukraine), e-mail: ischenko-mg@turboatom.com.ua, ORCID: 0000-0003-2251-5104

Liubov O. Slaston, Joint-Stock Company Turboatom (199, Moskovskyi Ave., Kharkiv, 61037, Ukraine), e-mail: kalembet@i.ua, ORCID: 0000-0002-9268-8134

Riza B. Sherfedinov, Joint-Stock Company Turboatom (199, Moskovskyi Ave., Kharkiv, 61037, Ukraine), e-mail: rizasherfedinov@gmail.com, ORCID: 0000-0002-5947-7802

 

Abstract

The paper presents an option of the steam condensing turbine K-325-23.5 (K-300 series) low pressure cylinder flow part improvement due to the last stage modernization. The K-325-23.5 turbine is designed to replace the outdated K-300 series turbines, which together with the K-200 series turbines form the basis of Ukraine’s thermal energy. In the modernized flow part, new last stage guide apparatus blades with a complex circular lean near the hub are used. The purpose of the modernization was to increase the low-pressure cylinder efficiency in the “bad” condenser vacuum to ensure that it did not “decrease” its efficiency at rated operating modes. The modernized low-pressure cylinder flow part is developed with the usage of modern methods of the viscous three-dimensional flow calculation based on the numerical integration of the Reynolds-averaged Navier-Stoks equations. For the turbulent effects, a two-parameter differential SST Menter turbulence model is applied, and for the hydraulic fluid real properties, the IAPWS-95 state equation is used. To construct the axial blades three-dimensional geometry, the original method, the initial data for which was the limited number of parameterized quantities, was used. The applied methods of gas-dynamic calculations and design of flow turbomachines are implemented in the IPMFlow software package, which is the development of the FlowER and FlowER-U software packages. The researched low-pressure cylinder flow part is limited by the last two stages (4th and 5th). A difference grid with a total element volume of more than 3 million is used to construct the calculation area. The research examined more than 20 options of the last stage stator blades. In the modernized flow part of the low-pressure cylinder last stage at rated operating mode, the gain of the efficiency coefficient (efficiency) is 0.9% and power – 0.61 MW. In the mode of “bad” condenser vacuum (with high pressure) a significant increase is achieved: efficiency – by 11.5%, power increased by almost 2 MW.

 

Keywords: spatial profiling, numerical modeling, spatial flow, gas-dynamic efficiency, steam turbine, last stage.

 

Full text: Download in PDF

 

References

  1. Petinrin, J. O. & Shaaban, M. (2012). Overcoming challenges of renewable energy on future smart grid. Telkomnika, vol. 10, no. 2, pp. 229–234. https://doi.org/10.12928/telkomnika.v10i2.781.
  2. (2017). Enerhetychna stratehiia Ukrainy na period do 2035 roku “Bezpeka, enerhoefektyvnist, konkurentospro-mozhnist” [Ukraine’s energy strategy for the period up to 2035 “Security, energy efficiency, competitiveness”]: Order of the Cabinet of Ministers of Ukraine dated August 18, 2017 No. 605-p., 66 p. (in Ukrainian).
  3. Shcheglyayev, A. V. (1993). Parovyye turbiny. Teoriya teplovogo protsessa i konstruktsii turbin [Steam turbines. Theory of the thermal process and turbine design]. Moscow: Energoatomizdat, 416 p. (in Russian).
  4. Denton, J. D. (1993). Learning flow physics from turbomachinery flow calculations by Dvorak, R. & Kvapilova, J. (Eds.). Proc. of the Int. Symp. on Experimental and Computational Aerothermodynamics of Internal Flows. Prague: SCMP Publication, pp. 23–51.
  5. ANSYS Fluent for CFD simulations. ANSYS: Official site, 2018. URL: http://www.ansys.com/Products/Fluids/ANSYS-Fluent.
  6. NUMECA Tubomachinery solution for CFD simulations and optimization. NUMECA international: Official site, 2020. URL: http://www.numeca.com/en_eu/turbomachinery.
  7. Rusanov, A., Rusanov, R., & Lampart, P. (2015). Designing and updating the flow part of axial and radial-axial turbines through mathematical modeling. Open Eng. (formerly Central European J. Eng.), vol. 5, iss. 1, pp. 399–410. https://doi.org/10.1515/eng2015-0047.
  8. Yangozov, A. & Lazarovski, N. (2009). Vliyaniye geometricheskoy formy soplovogo apparata na effektivnost preobrazovaniya energii v stupenyakh parovykh turbin [Influence of the geometric shape of the nozzle apparatus on the efficiency of energy conversion in the steps of steam turbines]. Ansys Advantage Rus, no. 11, pp. 29–34 (in Russian).
  9. D’Ippolito, G., Dossena, V., & Mora, A. (2011). The Influence of blade lean on straight and annular turbine cascade flow field. ASME J. Turbomachinery, vol. 133 (1), no. 011013, 9 p. https://doi.org/10.1115/1.4000536.
  10. Rusanov, A. V. & Yershov, S. V. (2008). Matematicheskoye modelirovaniye nestatsionarnykh gazodinamicheskikh protsessov v protochnykh chastyakh turbomashin [Mathematical modeling of unsteady gas-dynamic processes in flowing parts of turbomachines]. Kharkov: A. Podgorny Institute of Mechanical Engineering Problems NAS of Ukraine, 275 p. (in Russian).
  11. Rusanov, A., Shubenko, A., Senetskyi, O., Babenko, O., & Rusanov, R. (2019). Healting modes and design optimization of cogeneration steam turbines of powerful units of combined heat and power plant. Energetika, vol. 65, no. 1, pp. 39–50. https://doi.org/10.6001/energetika.v65i1.3974.
  12. Lampart, P. & Yershov, S. (2003). Direct constrained computational fluid dynamics based optimization of three-dimensional blading for the exit stage of a large power steam turbine. Transactions of ASME. J. Eng. for Gas Turbines and Power, vol. 125, no. 1, pp. 385–390. https://doi.org/10.1115/1.1520157.
  13. IAPWS-95. Revised Release on the IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use. IAPWS-95: Official site, 2019. URL: http://www.iapws.org.
  14. Rusanow, A. V., Lampart, P., Pashchenko, N. V., & Rusanov, R. A. (2016). Modelling 3D steam turbine flow using thermodynamic properties of steam IAPWS-95. Polish Maritime Research, vol. 23, no. 1, pp. 61–67. https://doi.org/10.1515/pomr-2016-0009.
  15. Yershov, S., Rusanov, A., Gardzilewicz, A., & Lampart, P. (1999). Calculations of 3D viscous compressible turbomachinery flows. Proc. 2nd Symp. on Comp. Technologies for Fluid/Thermal/Chemical Systems with Industrial Applications, ASME PVP Division Conf., 1–5 August 1999, Boston, USA, PVP, vol. 397 (2), pp. 143–154.
  16. Menter, F. R. (1994). Two-equation eddy viscosity turbulence models for engineering applications. AIAA J., vol. 32, no. 8, pp. 1598–1605. https://doi.org/10.2514/3.12149.
  17. Rusanov, A. V. & Pashchenko N. V. (2009). Aerodinamicheskoye sovershenstvovaniye tsilindra nizkogo davleniya parovoy turbiny moshchnostyu 200 MVt [Aerodynamic improvement of a low-pressure cylinder of a 200 MW steam turbine]. Problemy mashinostroyeniya – Journal of Mechanical Engineering, vol. 12, no. 2, pp. 7–15 (in Russian).

 

Received 24 February 2020

Published 30 March 2020