Unshrouded rotor tip clearance effects in expander cycle turbines
Författare
Summary, in English
A series of subsequent simulations is thus used to judge the impact of varied blade/stage design parameters.
Two turbine layouts are defined for identical operating conditions and shaft power. The flow in the unshrouded rotor blade row is analyzed for the influence of varying tip clearance size and the dependency on stage velocity triangles. – Known correlations for tip clearance losses (typically used in mean line predictions) are used, though the blade row geometry considered is beyond the limits the correlations are intended for. The absolute loss level found in CFD simulations differs significantly from what is expected when using loss correlations. Still the variation with tip gap size is predicted well by some of the investigated models. As dependency of tip clearance losses on stage velocity triangles is considered, none of the tested correlations gives results consistent with the numerical simulations. The use of standard correlations ‘beyond the limits’ is thus considered to introduce high uncertainty.
Due to the good consistency between LDA and numerical results, the conclusions are considered to be valid for stage designs similar to the ones analyzed.
Avdelning/ar
Publiceringsår
2002
Språk
Engelska
Publikation/Tidskrift/Serie
Proceedings of the ASME Turbo Expo
Dokumenttyp
Konferensbidrag
Förlag
American Society Of Mechanical Engineers (ASME)
Ämne
- Energy Engineering
Nyckelord
- loss correlation
- tip clearance
- CFD
- LDA
Conference name
2002 ASME Turbo Expo: Land, Sea and Air
Conference date
0001-01-02
Conference place
Netherlands
Status
Published
ISBN/ISSN/Övrigt
- GT2002-30338