Experimental and Numerical Investigation of Film Cooling Effectiveness on Squealer Tip of a Turbine Blade

Document Type : Research Article

Authors

1 School of Mechanical Engineering/ Iran University of Science and Technology/ Tehran / Iran

2 School of Mechanical engineering / Iran University of Science and Technology / Tehran / Iran

3 School of Mechanical Engineering / Iran University of Science and Technology / Tehran / Iran

Abstract

In this article, the effects of squealer on aerodynamic performance and thermal load distribution on the blade tip region are investigated. Experimental results are presented at blowing ratios of 0.5, 0.75, 1.0, and 1.5. The film-cooling effectiveness is measured via the steady-state heat transfer measurement technique. A numerical approach has been applied to compare the film cooling performance and aerodynamic losses in the plane and recessed blade tips. The experimental results indicate that, as the blowing ratio increases, the coolant jets provide better cooling coverage on the cavity surface. The numerical results show that the plane tip film-cooling effectiveness is lower than that for the squealer tip. It can be observed that, for the plane and squealer tip configurations, as the blowing ratio increased, the heat transfer coefficient decreased by about 43% and 44%, respectively. Moreover, the film-cooling effectiveness on squealer tip surface and rim walls increased by 15% and 23%, respectively. Furthermore, the lower heat transfer coefficient was observed at a higher blowing ratio on the surfaces mentioned above. The squealer tip geometry showed better aerodynamic performance, which results in weaker tip leakage vortex and lower tip leakage flow rate with respect to the plane tip geometry.

Keywords

Main Subjects

References

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Amirkabir Journal of Mechanical Engineering
Volume 53, Issue 3
June 2021
Pages 1521-1536

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