Affiliation:
1. Turbine Heat Transfer Laboratory, Department of Mechanical Engineering, Texas A&M University, College Station, TX 77843-3123
Abstract
The detailed distributions of heat transfer coefficient and film cooling effectiveness on a gas turbine blade tip were measured using a hue detection based transient liquid crystals technique. Tests were performed on a five-bladed linear cascade with blow-down facility. The Reynolds number based on cascade exit velocity and axial chord length was 1.1×106 and the total turning angle of the blade was 97.7°. The overall pressure ratio was 1.2 and the inlet and exit Mach numbers were 0.25 and 0.59, respectively. The turbulence intensity level at the cascade inlet was 9.7%. The blade model was equipped with a single row of film cooling holes at both the tip portion along the camber line and near the tip region of the pressure side. All measurements were made at the three different tip gap clearances of 1.0%, 1.5%, and 2.5% of blade span and the three blowing ratios of 0.5, 1, and 2. Results showed that, in general, heat transfer coefficient and film effectiveness increased with increasing tip gap clearance. As blowing ratio increased, heat transfer coefficient decreased, while film effectiveness increased. Results also showed that adding pressure side coolant injection would further decrease the blade tip heat transfer coefficient but increase film-cooling effectiveness.
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics,General Materials Science
Reference20 articles.
1. Han, J. C., Dutta, S., and Ekkad, S. V., 2000, Gas Turbine Heat Transfer and Cooling Technology, Taylor & Francis, New York.
2. Mayle, R. E., and Metzger, D. E., 1982, “Heat Transfer at the Tip of an Unshrouded Turbine Blade,” Proc. Seventh Int. Heat Transfer Conf., Hemisphere Pub., pp 87–92.
3. Metzger, D. E., Bunker, R. S., and Chyu, M. K., 1989, “Cavity Heat Transfer on a Transverse Grooved Wall in a Narrow Flow Channel,” ASME J. Heat Transfer, 111, pp. 73–79.
4. Chyu, M. K., Moon, H. K., and Metzger, D. E., 1989, “Heat Transfer in the Tip Region of Grooved Turbine Blades,” ASME J. Turbomach., 111, pp. 131–138.
5. Metzger, D. E., Dunn, M. G., and Hah, C., 1991, “Turbine Tip and Shroud Heat Transfer,” ASME J. Turbomach., 113, pp. 502–507.
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