Abstract
The tip gap flow and aerodynamic loss generation over a plane tip equipped with a “constant-width suction-side” (CWSS) winglet and a “varying-width suction-side” (VWSS) winglet have been investigated in a turbine cascade. For a fixed tip gap of h/c = 2.0%, three different winglet widths of w/p = 5.28, 10.55, and 15.83% are tested for the CWSS winglet. The VWSS winglet is designed based on flow visualization and has almost the same winglet area as the CWSS winglet of w/p = 15.83%. In general, the suction-side winglets have a role to increase aerodynamic loss in the tip leakage vortex region but reduce aerodynamic loss in the passage vortex region. For the CWSS winglet, the total-pressure loss coefficient mass-averaged all over the measurement plane has no appreciable changes with increasing w/p from 0.0 to 10.55%, but tends to decrease with further increment of w/p. The VWSS winglet performs better in reducing aerodynamic loss in the passage vortex region than the CWSS winglet of w/p = 15.83% but leads to a little bit higher aerodynamic loss in the tip leakage vortex region. The aerodynamic loss reduction by the VWSS winglet is 7.4% in comparison with the plane tip without winglet, and is about 60% lower than that by the widest CWSS winglet.
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Recommended by Associate Editor Byeong Rog Shin
Yong Cheol Seo received his B.S. and M.S. degrees in Mechanical Engineering from Kumoh National Institute of Technology in 2010 and 2012, respectively. He is currently a researcher of New Transportation Infrastructures Research Division at the Korea Railroad Research Institute.
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Seo, Y.C., Lee, S.W. Tip gap flow and aerodynamic loss generation in a turbine cascade equipped with suction-side winglets. J Mech Sci Technol 27, 703–712 (2013). https://doi.org/10.1007/s12206-012-1258-x
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DOI: https://doi.org/10.1007/s12206-012-1258-x