Numerical prediction of losses in the low pressure last stage blade

• Autorzy: Chmielniak T. , Łukowicz H. , Wróblewski W. , Dykas S.
• Języki publikacji: EN

Abstrakty

EN

The aim of presented research is to estimate the losses in the flow of steam through the rotor of last stage LP steam turbine. In this case two types of losses may take place, namely aerodynamic (profile, secondary flow, leakage) and thermodynamic (due to the heat addition caused by condensation). In the paper three different calculation models have been compared. The first one is the streamline curvature method (SCM), used on the meridional plane with correlation of losses, and the other are based on the Reynolds averaged Navier-Stokes governing equations. The N-S equations for the 3D steam flow are solved using two models for the liquid phase. The first one is an equilibrium dry/wet steam model and the second one is the nonequillibrium model. In this case, the governing equations are coupled with the system of partial differential equations describing the liquid phase. The real gas local equation of state is used in calculation of the water-steam properties and thermodynamic functions. The homogeneous nucleation processes in the water steam are modeled using the classical nucleation theory. Flow in the considered case has strong 3-D character and real gas effects are significant, which causes significant losses in the last stages. The results of calculations of the wet steam flow are discussed and compared.

Słowa kluczowe

EN

steam turbines; flow modeling; numerical methods; wet steam; losses

• Wydawca: Wydawnictwo Instytutu Maszyn Przepływowych PAN
• Czasopismo: Transactions of the Institute of Fluid-Flow Machinery
• Rocznik: 2003
• Tom: nr 113
• Strony: 119--128
• Opis fizyczny: Bibliogr. 19 poz., wykr.

Twórcy

autor

Chmielniak T.

• Institute of Power Engineering and Turbomachinery Silesian University of Technology, Konarskiego 18, 44-101 Gliwice, Poland

autor

Łukowicz H.

• Institute of Power Engineering and Turbomachinery Silesian University of Technology, Konarskiego 18, 44-101 Gliwice, Poland

autor

Wróblewski W.

• Institute of Power Engineering and Turbomachinery Silesian University of Technology, Konarskiego 18, 44-101 Gliwice, Poland

autor

Dykas S.

• Institute of Power Engineering and Turbomachinery Silesian University of Technology, Konarskiego 18, 44-101 Gliwice, Poland

Bibliografia

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