Patent attributes
A large tapered air cooled turbine blade having a serpentine flow cooling circuit with a first leg located adjacent to a leading edge of the blade and a third leg at the trailing edge, where the third leg includes an impingement cooling channel formed along the upper span of the blade on the trailing edge. The impingement cooling cavity includes impingement holes connected to the third leg of the serpentine flow circuit to provide cooling air into the impingement cavity, which is then discharged through exit cooling holes spaced along the upper span of the trailing edge of the blade. A separate cooling channel is formed along the lower span of the trailing edge and includes exit cooling holes to discharge cooling air through the lower span trailing edge. The upper span impingement cavity is supplied with separate cooling air from the lower span cooling cavity. The blade is formed from cores in which the trailing edge portion of the blade is formed from a first core member that forms the last leg of the serpentine flow circuit and the impingement cavity of the upper span, and a second core member that forms the lower span cooling circuit. The first core member includes a core tie with a print out hole in which a print out on the second core is inserted to form a core assembly used to form the trailing edge cooling circuit.
