Large tip clearances in the region of six percent span exist in the high pressure stages of compressors of industrial gas turbines. The over tip clearance flow causes significant blockage and accounts for the largest proportion of loss in the high pressure compressor. This paper examines large tip clearances in two different compressor cascades. The first was a cascade of controlled-diffusion blades and the second cascade had geometry more representative of modern engine practise. The second cascade also featured realistic inlet boundary layer conditions delivered by an upstream injection system. Increasing the understanding of such flows will allow for improvements in the design of such compressors. The key conclusions of this paper are: a) At large tip clearances the tip clearance is the primary variable influencing the flow pattern, blade geometry is a secondary consideration; b) The blade geometry has a significant influence on loss generation through the cascade; c) With increasing tip clearance the loss generation through the cascade can diminish but the flow turning is much reduced; and d) The blade loading at the tip can increase at large tip clearances.
Large Tip Clearance Flows in Two Compressor Cascades
- Views Icon Views
- Share Icon Share
- Search Site
Williams, R, Ingram, G, & Gregory-Smith, D. "Large Tip Clearance Flows in Two Compressor Cascades." Proceedings of the ASME Turbo Expo 2010: Power for Land, Sea, and Air. Volume 7: Turbomachinery, Parts A, B, and C. Glasgow, UK. June 14–18, 2010. pp. 391-402. ASME. https://doi.org/10.1115/GT2010-22952
Download citation file: