The paper presents experimental results for performance of full-coverage film cooled surfaces. Effectiveness and heat transfer are measured on plane surfaces with discrete injection through the surface at an array of points into a turbulent mainstream boundary layer. The injection is normal to the surface, through circular holes arranged in both in-line and staggered patterns with 4.8 hole diameters used for both the row-to-row spacing and the hole-to-hole spacing within a single row. Both the film and mainstream fluids are air, and property differences are kept small throughout the study. Uniform injection over the entire array at film-to-mainstream velocity ratios of 0.1 and 0.2 with a uniform wall temperature boundary condition are covered. Results are compared with predictions using superposition of available single hole local effectiveness values.

Results are presented from experimental measurements of heat-transfer rates on surfaces which are cooled by injection through one to four rows of evenly spaced, flush, normal injection holes arranged in staggered and in-line patterns with hole spacings of 4.8 dia. Film cooling performanc is evaluated in both the injection and downstream recovery regions from transient tests which provide a uniform wall temperature boundary condition. Both the film and mainstream fluids are air, and film-to-mainstream mass velocity ratios of 0.1, 0.2, 0.3, and 0.5 are covered.

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