The aerothermal performance of a winglet tip with cooling holes on the tip and on the blade surface near the tip is reported in this paper. The investigation was based on a high pressure turbine cascade. Experimental and numerical methods were used. The effects of the coolant mass flow rate are also studied. Because the coolant injection partially blocks the tip leakage flow, more passage flow is turned by the blade. As a result, the coolant injection on the winglet tip reduces the deviation of the flow downstream of the cascade due to the tip leakage flow. However, the tip leakage loss increases slightly with the coolant mass flow ratio. Both the computational fluid dynamics tools and experiments using the Amonia–Diazo technique were used to determine the cooling effectiveness. On the blade pressure side surface, low cooling effectiveness appears around the holes due to the lack of the coolant from the cooling hole or the lift-off of the coolant from the blade surface when the coolant mass flow is high. The cooling effectiveness on the winglet tip is a combined effect of the coolant ejected from all the holes. On the top of the winglet tip, the average cooling effectiveness increases and the heat load decreases with increasing coolant mass flow. Due to its large area, the cooled winglet tip has a higher heat load than an uncooled flat tip at engine representative coolant mass flow ratio. Nevertheless, the heat flux rate per unit area of the winglet is much lower than that of an uncooled flat tip. The cycle analysis is carried out and the effects of relative tip-to-casing endwall motion are address.
The Aerothermal Performance of a Cooled Winglet Tip in a High Pressure Turbine Cascade
Department of Engineering,
Contributed by the International Gas Turbine Institute (IGTI) of ASME for publication in the JOURNAL OF TURBOMACHINERY. Manuscript received November 12, 2011; final manuscript received November 29, 2011; published online March 25, 2013. Editor: David Wilser.
- Views Icon Views
- Share Icon Share
- Cite Icon Cite
- Search Site
Zhou, C., Hodson, H., Tibbott, I., and Stokes, M. (March 25, 2013). "The Aerothermal Performance of a Cooled Winglet Tip in a High Pressure Turbine Cascade." ASME. J. Turbomach. May 2013; 135(3): 031005. https://doi.org/10.1115/1.4006611
Download citation file:
- Ris (Zotero)
- Reference Manager