Computational Study on Effect of Variation of Pitch-Chord on Secondary Losses in  Rectilinear Turbine Cascade

Pulijala Shravya

doi:10.4236/eng.2015.711064

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Engineering > Vol.7 No.11, November 2015

Computational Study on Effect of Variation of Pitch-Chord on Secondary Losses in Rectilinear Turbine Cascade ()

Pulijala Shravya

Department of Mechanical Engineering, Birla Institute of Technology and Science, Pilani, India.

DOI: 10.4236/eng.2015.711064 PDF HTML XML 4,077 Downloads 4,496 Views Citations

Abstract

Losses in turbine cascade are categorized as profile loss, secondary loss, tip clearance loss and annulus loss. Profile loss occurs due to development of boundary layer on surface of blade [1]. Increase in thickness of boundary layer and adverse pressure gradient increases profile loss. Secondary loss occurs due to turning of flow through flow passage which results in blowing of energy from pressure side to suction side. In turbine rotor blade suction surface leads and tip clearance loss occurs due to leakage of air from pressure side to suction side of the blade through tip clearance. Annulus loss occurs due to development of boundary layer on stationary row of blade. It also occurs in moving row of blade but in moving row of blades boundary layer is scraped by flow over the blades. This paper presents effects of variation of pitch-chord ratio on secondary loss.

Keywords

Turbine Cascade, Pitch-Chord Ratio, Secondary Losses

Share and Cite:

Shravya, P. (2015) Computational Study on Effect of Variation of Pitch-Chord on Secondary Losses in Rectilinear Turbine Cascade. Engineering, 7, 733-741. doi: 10.4236/eng.2015.711064.

Conflicts of Interest

The authors declare no conflicts of interest.

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