A methodology for online rotor stress monitoring using equivalent Green’s function and steam temperature model

• Autorzy: Banaszkiewicz M. , Dominiczak K.
• Języki publikacji: EN

Abstrakty

EN

The requirement of high operational flexibility of utility power plants creates a need of using online systems for monitoring and control of damage of critical components, e.g., steam turbine rotors. Such systems make use of different measurements and mathematical models enabling calculation of thermal stresses and their continuous control. The paper presents key elements of the proposed system and discusses their use from the point of view of thermodynamics and heat transfer. Thermodynamic relationships, well proven in design calculations, were applied to calculate online the steam temperature at critical locations using standard turbine measurements as input signals. The model predictions were compared with operational data from a real power plant during a warm start-up and show reasonably good accuracy. The effect of variable heat transfer coefficient and material properties on thermal stresses was investigated numerically by finite element method (FEM) on a cylinder model, and a concept of equivalent Green’s function was introduced to account for this variability in thermal stress model based on Duhamel’s integral. This approach was shown to produce accurate results for more complicated geometries by comparing thermal stresses at rotor blade groove computed using FEM and Duhamel’s integral.

Słowa kluczowe

EN

Steam turbine; thermal stress; Green's functions; Duhamel’s integral

• Wydawca: Wydawnictwo Instytutu Maszyn Przepływowych PAN
• Czasopismo: Transactions of the Institute of Fluid-Flow Machinery
• Rocznik: 2016
• Tom: nr 133
• Strony: 13--37
• Opis fizyczny: Bibliogr. 33 poz., rys.

Twórcy

autor

Banaszkiewicz M.

• GE Power sp. z o.o., Stoczniowa 2, 82-300 Elbląg, Poland
• Institute of Fluid Flow Machinery, Polish Academy of Sciences, 80-231 Gdańsk, Fiszera 14, Poland

autor

Dominiczak K.

• GE Power sp. z o.o., Stoczniowa 2, 82-300 Elbląg, Poland
• Institute of Fluid Flow Machinery, Polish Academy of Sciences, 80-231 Gdańsk, Fiszera 14, Poland

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