| An experimental investigation of the influence of upstream turbulence on discrete-hole film cooling of a model blade in confined cross flow is presented and discussed. A model blade and test section were designed and constructed. A system for constant-temperature hot-wire anemometry was implemented. A microcomputer-based data acquisition, control, and processing system was designed and implemented. The model blade was a blunt body with a semicircular leading edge, a flat after body, and a tapered trailing edge. Local heat transfer coefficients without injection of a secondary fluid were determined using a thin-film technique. In the film cooling studies, two rows of discrete injection holes at $pm$30$spcirc$ from the stagnation line were used. The injection tubes were oriented normal to the surface of the model blade and were coplanar with the primary flow velocity vector.;Nominal turbulence intensities of 0.7%, 9.8%, and 14.4% at a location 1.3 diameters upstream of the stagnation line on the semicircular leading edge of the model blade were investigated. The range of Reynolds number, based on the diameter of the semicircular leading edge and upstream velocity, was 23,000 to 75,000. In the discrete-hole film cooling studies, mass flux ratios in the range 0.6 $<$ M $<$ 2.0 were considered. The heat transfer results are presented in terms of the distributions of local Nusselt number and a nondimensional temperature on the surface of the blade. The results of the film cooling studies are presented in terms of the distributions of the effectiveness. |
