ciência/science application of steam turbines...
TRANSCRIPT
APPLICATION OF STEAM TURBINES SIMULATION MODELS IN POWER GENERATION SYSTEMS
C.S.Bresolin,
P.S. Schneider,
H.A. Vielmo
and F.H.R.França
Universidade Federal do Rio Grande do Sul
Departamento de Engenharia Mecânica
Rua Sarmento Leite, 425.
90050-170 Porto Alegre RS.
ABSTRACT
The goal of this work is to simulate partial load operation of steam turbines in different controlling modes. An isentropic efficiency function is associated to a specific steam turbine. The Schegliáiev and the Stodola's Ellipse Law, relating levels of pressure with mass flow, are compared. The proposed operational modes are: a) sliding pressure; b) throttling valve; c) nozzle valve. As a conclusion, Schegliáiev and Stodola's models leads to very similar results and the operational modes by valves establishes theoretical limits of operation for steam turbines. The sliding pressure control is more efficient considering design operation.
Keywords: steam turbines, partial loads, isentropic efficiency, Stodola's Ellipse Law, nozzle analogy
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Engenharia Térmica (Thermal Engineering), Vol. 5 - Nº 01 - July 2006 73
Ciência/Science
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Engenharia Térmica (Thermal Engineering), Vol. 5 - Nº 01 - July 2006 74
Ciência/Science Bresolin et al. Application of Steam Turbines ...
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Engenharia Térmica (Thermal Engineering), Vol. 5 - Nº 01 - July 2006 75
Ciência/Science Bresolin et al. Application of Steam Turbines ...
Engenharia Térmica (Thermal Engineering), Vol. 5 - Nº 01 - July 2006 76
Ciência/Science Bresolin et al. Application of Steam Turbines ...
Engenharia Térmica (Thermal Engineering), Vol. 5 - Nº 01 - July 2006 77
Ciência/Science Bresolin et al. Application of Steam Turbines ...