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ISSN Online: 2377-424X

ISBN Print: 0-89116-909-1

International Heat Transfer Conference 9
August, 19-24, 1990 , Jerusalem, Israel

EXPERIMENTAL STUDY ON THE EFFECT OF CONCAVE AND CONVEX CURVATURES ON FILM COOLING EFFECTIVENESS

Get access (open in a dialog) DOI: 10.1615/IHTC9.920
pages 341-346

Abstract

Experiment on film cooling effectiveness has been conducted on concave and convex surfaces with a row of injection holes by using a mass transfer technique. To investigate solely the effect of curvatures, the pressure gradient variations in the streamwise direction are minimized by modifying the geometric configuration of the test sections. Results are obtained for a 35° inclined injection for different blowing rates of 0.2, 0.5, 0.75 and 1.0, respectively. In addition, schlieren photographs are taken to visualize the trajectories of injection fluid by introducing CO2 gas through an injection pipe.
The results show that for small blowing rates, the trend of the film cooling effectiveness is similar both on concave and on convex surfaces, and it decreases rapidly in the streamwise direction. As the blowing rate increases, the film cooling effectiveness on the concave surface becomes larger than that on the convex surface. Especially, when the blowing rate is unity, the film cooling effectiveness decreases remarkably on the convex surface.