Experimental Study on Overall Cooling Effectiveness of Turbine Nozzle Guide Vane with Impingement-Cutback Structure

The overall cooling performance of turbine nozzle guide vane, with the impingement-cutback structure, is experimentally studied in actual-scale cascade. gas high temperature used to achieve actual dynamic viscosity coefficient and density ratios. coolant-to-gas mass flow ratio (KG) varies between 0.034 0.050 gas-to-coolant (KT) 1.5 2.4. local Overall Cooling Effectiveness (OCE) on middle cross-section vane obtained. experimental results reveal that lowest value OCE achieves a 10% relative arc length suction side vane; however, highest appears at 40% pressure vane. averaged values are respectively enhanced by 19.45%, 24.22%, 35.57% ratios equal 1.7, 1.9, 2.3, an increase KG from 0.050. Added that, it was identified KT 1.7 2.3 leads decrease OCE. comparison show this characteristic becomes dramatical while 0.034. higher greater influence KG, which illustrated clearly compared