FUNDAMENTALS OF THE THEORY OF VENTILLATION PROCESSES IN THE STEAM TURBINES TPP

 The article proposes the theoretical framework of ventilation processes emerging and going on in the stages of TPP steam turbines during the operating regimes with small-quantity volumetric flow rates in the low-pressure cylinder. The basic theory includes new physicomathematical models for estimating the ventilating capacity losses and ventilation heatings-up of the steam and the air-gas channel of the turbine; search and investigation of the factors causing the increased momental loads on the blade wheels of the finale stages which are likely to lead to destruction of the rotating blades. The paper renders the practical results of utilizing the theoretical framework of ventilation processes.

The author obtains a new mathematical relation for high-accuracy assessment of the ventilating capacity losses accounting for all the diversification of parameters defining the level of these losses (it is established that the Coriolis force contributes twice as much to the ventilating capacity losses as the centrifugal force). Seven ordinary formulae obtained on its basis provide a separate stage ventilation-losses immediate evaluation (with rotation blades of the finale stage not unwinding from the turning, with rotation blades of the finale and intermediate stages unwinding from the turning), in the turbine altogether-vapor-evacuated including by readings of the regular instruments located at the connecters of the exhaust part of the lowpressure cylinder.

As the cornerstone of the new ventilation heating-up evaluation system the author lays two experimentally established facts: the ventilating capacity losses are practically constant at working steam negligible volumetric flow rates; symmetrical ventilating flows in the blade channel mingle entirely to the moment of their split up at the periphery. This renders possible estimating the complete enthalpy increment of the steam being discharged from a stage in relation to the enthalpy of the steam being drawn into the blade channel of the blade wheel out of the vapor space of the condenser. The research establishes and acknowledges the influence of a wide spectrum of parameters on the ventilating capacity losses level and ventilation heatings-up in a turbine stage, indicates the measures for them. The estimation results of ventilating losses and ventilation heatings-up are close to the experimental findings of different researchers.

1. Neuimin, V. M. (2011) Universal Mathematical Relation for High-Precision Evaluation of Convection Power Losses in the Turbine Stage of TPP. Nadezhnost' i Bezopasnost' Energetiki [Reliability and Safety of Power Industry], 1 (12), 2 (13), 56–65, 66–76 (in Russian).

2. Neuimin, V. M. (2009) (2010) On Physico-Mathematical Modeling for Evaluation of the Ventilation Heating-up Level of the Flowing Part of the TPP-Turbine. Part. 1. Nadezhnost' i Bezopasnost' Energetiki [Reliability and Safety of Power Industry], 4 (7), 1 (8), 40–43, 37–42 (in Russian).

3. Usachev, I. P., Efimenko, E. N., Il'inykh, V. V., Koliasnikov, V. V., Neuimin, V. M. (1981) Excitation of Axial Vacillation of the Steam Turbines Wheels in the Running Regime. Energeticheskoe Mashinostroenie [Power Engineering Industry], 3, 5–9 (in Russian).

4. Usachev, I. P., Neuimin, V. M. (2009) On Axial-Vacillation Excitation in the Moving Blades Grids of LPC-Stages of the Modern Steam Turbines of District Heat Supply in the Starting and Stopping Regimes. The Problems of Vibration, Vacillation Balancing, Vibro- Monitoring and Diagnostics of Power Plants Equipment. Proceedings of the International Scien- tific and Technical Meeting. Moscow: All-Russian Heat Engineering Research Institute, 154 (in Russian).

5. Neuimin, V. M. (2014) Estimating Method of Convection Power Losses in Stages of the TPP Steam Turbines. Teploenergetika [Heat-Power Engineering], 10, 73–80 (in Russian).

6. Stodola, A. (1945) Steam and Gas Turbines. New York, Peter Smith. 1356 p.

7. Matveenko, V. ?., Agafonov, V. N. (1984) Peculiarities of the Steam Turbines LPC Operating in Low Flow Rate Regimes. Energeticheskoe Mashinostroenie: Obzornaia Informatsiia [Power Engineering: an Overview], 12, 54 (in Russian).

8. Kotlyar, I. V., Konchakov, ?. I. (1983) Universal Computing Method for Convec- tion Losses in the Partial Turbine Stage. Energeticheskoe Mashinostroenie. Respublikan- skii Mezhvedomstvennyi Nauchno-Tekhnicheskii Sbornik [Power Engineering Industry. Repub- lican Interdepartmental Scientific and Technical Collection]. Kharkiv, Vishcha Shkola, 35, 51–60 (in Russian).

9. Kotlyar, I. V., Kuznetsov, Yu. P., Chuvakov, ?. B. (1993). The Method of De- tailed Convection-Losses Computation in the Partial Turbine Stage. Izvestyia Vysshikh Ucheb- nykh Zavedenii i Energeticheskikh Ob’edinenii SNG – Energetika [Proceedings of CIS Higher Education Institutions and Power Engineering Associations – Energetika], 11–12, 101–104 (in Russian).

10. Arakelian, E. K., Starshinov, V. ?. (1993). Thermal Power Plant Equipment Operational Economy and Maneuverability Increase. Moscow, MPEI-Press. 326 p. (in Russian).

11. Il’in, ?. ?., Tarakanov, S. V. (1984) Power Losses on Friction and Convection at K-200-130 Operating in Low Flow-Rate and Motor Regimes. Development of High-Efficiency Power-Generating Equipment. Proceedings of the Moscow Power Engineering Institute. Moscow, Issue 623, 121–127 (in Russian).

12. Novoselov, V. B. (1988) On Protection of the District-Heating Turbine Against Recycling Steam Flows from the District Heaters at the Falloff of the Electric Loading. Energomashinostroenie [Power Plant Engineering], 9, 46–49 (in Russian).

13. Karnitskiy, N. B. (1999) Synthesis of Reliability and Economical Efficiency of the TPP Heat and Power Equipment. Minsk, VUZ-UNITY Publ. 224 p. (in Russian).

14. Balabanovich, V. K. (2000) Upgrading Schemes and Regimes of Duty of the Heat-Supply Steam-Turbine Plants. Minsk, PolyBig Publ. 189 p. (in Russian).

15. Kostyuk, ?. G., Trukhniy, ?. D., Lomakin, ?. D. (2004) On Conditions of Turbi- nes ?-250/300-23,5 TMZ Transition to the Regime of Duty without Rotating Blades of the Last Stages. Teploenergetika [Heat-Power Engineering], 5, 23–30 (in Russian).

16. Zaryankin, ?. ?., Zroichikov, N. A., Ermolaev, G. V., Fichoriak, O. M. (2005) Expedience Evaluation of the Heat-Supply Turbine ?-250/300-240 Operation without the Last Stage in the LPC. Teploenergetika [Heat-Power Engineering], 6, 14–18 (in Russian).

17. N e u i m i n, V. M. (2015) The Computation Results of the Convection Power Losses in the Stages of the TPP-Steam Turbines. Energetik [Energetic], 1, 50–55 (in Russian).

18. N e u i m i n, V. M., Usachev, I. P., Skorobogatykh, V. I. (2004) Practical Operating Experience of Turbine P?-140 without the Last Stage. Teploenergetika [Heat-Power Engi- neering], 5, 31–35 (in Russian).

19. Usachev, I. P., Neuimin, V. M., Zhuchenko, L. ?. (1979) On the Root Separation in the Axle Turbine Stage. Energeticheskoe Mashinostroenie [Power Engineering Industry], 3, 9–12 (in Russian).

20. Khaaze, R. (1967) Thermodynamics of Irreversible Processes. Moscow, Mir. 544 p. (in Russian).

21. Ponomarev, V. N. (1976) Operation Study of the Turbine Stage on Partial Loading. Energeticheskoe Mashinostroenie [Power Engineering Industry], 2, 11–13 (in Russian).

22. Neuimin, V. M. (2011) On Erosive-Wear Reduction Measures of the Rotating Blades of the Modern TPP-Steam Turbines. Energetik[Energetik],3,10–18(inRussian).

23. Neuimin, V. M., Usachev, I. P. (1978) On the Issue of the LPC-Cooling of the High-Capacity Turbines. Development and Research of the Elements of Power Equipment. Proceedings CKTI [Research and Development Association on Research and Design of Power Equipment Named. Polzunov]. Leningrad, Issue 157, 23–25 (in Russian).

24. Grachev, ?. E., Neuimin, V. M. (2014) A New Technique for the Rotating Blades Hardening of the Last Stage of the High-Capacity TPP-Steam Turbine. TPA. Truboprovodnaia Armatura i Oborudovanie [TPA. Piping Accessories and Equipment], 5 (74), 66–68 (in Russian).

25. Neuimin, V. M., Usachev, I. P., Tikhomirov, A. N., Golovin, V. V. (1990) Functional and Cost Analysis of the District-Heating Turbines: Unified Air-Gas Channel of Low Pressure. Tiazheloe Mashinostroenie [Heavy Engineering], 8, 11–13 (in Russian).

26. Neuimin , V. M. (2014) On the Choice of the Rotating Blade Length of the Last Stage of the High-Capacity TPP-Steam Turbine. Energetik [Energetik], 1, 15–20 (in Russian).