ISSN Online: 2377-424X
ISBN Print: 0-89116-299-2
International Heat Transfer Conference 7
FILM COOLING EFFECTIVENESS OF DISCRETE HOLES MEASURED BY MASS TRANSFER AND LASER INTERFEROMETER
摘要
Film cooling of discrete holes at different
injection angles and compound-angles was studied
experimentally along the flat plate. After a certain
amount of carbon dioxide had been mixed with
the air injection stream, the carbon dioxide concentration
measurements were carried out downstream
of the film-cooling holes by the chromatograph.
The He-Ne interferometer and Schlieren optical
equipment were used to study the flow fields
near the injection holes. The results measured by
heat-mass transfer analogy and the results observed
by optical instruments near the film injection
holes agree with each other very well over the wide
range of blowing rates. The recirculation zone
near the film injection holes was carefully studied
at different injection angles, blowing rates and
momentum ratios. It was observed that at a given
value of blowing rate M, the rectangular holes and
compound-angle round holes gave higher effectiveness
than the round holes.