Analytical and experimental investigations were conducted to determine the cooling effectiveness and mechanical durability of a forcedconvection air-cooled strut-supported blade. Two blades, each consisting of a finned internal load-carrying member, or strut, to which a two-piece base and a two-piece airfoil shell were attached by brazing, were investigated in a modified turbojet engine using an external cooling-air supply.nExperimental results obtained at rated engine speed (11,500 rpm and turbine tip speed of 1300 ft/sec), a turbine-inlet temperature of about 1640° F, and a cooling-air temperature of about 200° F at the blade base indicated that substantial differences between the effective gas temperature and strut temperature were obtained throughout the entire range of coolant-to-combustion-gas flow ratio investigated. For example, at a coolant-to-combustion-gas flow -ratio of 0.01, the average strut temperature was about 400° F below the effective gas temperature.
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