Computational Study of Film Cooling Effectiveness for a Comparison of Cylindrical, Square and Triangular Holes of Equal Cross-Sectional Area
Film cooling effectiveness is studied computationally for a comparison of circular, square and two types of equilateral triangular holes with an inclination of 30o with streamwise direction. Reynolds number based on the freestream velocity and hole diameter is 10364. Length to diameter ratio of c...
Main Authors: | , |
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Format: | Article |
Language: | English |
Published: |
Mehran University of Engineering and Technology
2010-10-01
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Series: | Mehran University Research Journal of Engineering and Technology |
Subjects: | |
Online Access: | http://publications.muet.edu.pk/research_papers/pdf/pdf37.pdf |
Summary: | Film cooling effectiveness is studied computationally for a comparison of circular,
square and two types of equilateral triangular holes with an inclination of 30o with
streamwise direction. Reynolds number based on the freestream velocity and hole
diameter is 10364. Length to diameter ratio of circular hole is 4, which is representative
of gas turbine engines. The coolant to mainstream density ratio is 0.92. Main flow is
supplied at the temperature of 293.15K and coolant is supplied at 318.15K. Centerline
and laterally averaged effectiveness are presented for film cooling measurements.
Current computational results for circular hole are compared with experimental
results. Computational results are well in agreement with the experimental results
even for high blowing ratios. Blowing ratios ranging from 0.33-2.0 have been
investigated. It is observed that triangular hole having lateral straight edge on leeward
side shows much higher effectiveness values than circular film cooling hole case in
the near hole region and almost similar coolant jet height as that in case of circular
film cooling. Also it is observed that triangular hole having lateral straight edge on
windward side and converging corner on leeward side shows lesser coolant jet height
and higher film cooling effectiveness in the region x/D>10, especially at blowing
ratios greater than 1.0. |
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ISSN: | 0254-7821 2413-7219 |