TURBULENCE INTENSITY EFFECTS ON FILM-COOLING AND HEAT-TRANSFER FROM COMPOUND ANGLE HOLES WITH PARTICULAR APPLICATION TO GAS-TURBINE BLADES

This paper reports an experimental investigation into the effects of f reestream turbulence intensity on the film cooling effectiveness and h eat transfer characteristics of two staggered rows of compound angle h oles with particular application to high temperature gas turbine blade s. Turbulence intensity effects on film cooling and heat transfer char acteristics are investigated for three blowing rates: 0.5, 1.0 and 1.7 . Increasing the freestream turbulence intensity has caused a. signifi cant reduction in the local film cooling effectiveness but increased t he Stanton number, especially at the blowing rate of 0.5. The effect o f freestream turbulence on the film cooling and heat transfer characte ristics from compound angle holes tends to have similar effects to tha t when simple angle holes are used. (C) 1998 Elsevier Science Ltd. All rights reserved.