COOLING STRUCTURE TO COOL PLATFORM FOR DRIVE BLADES OF GAS TURBINE

摘要

A mechanism for cooling the platform for the drive blades of a gas turbine, which uses a simple configuration which will reliably cool the platform, the mechanism being constituted by cooling channels in the interior of the platform which open out from one of the cooling air channels for cooling the turbine blades and which exit the platform through the edge nearest the tail. In a preferred embodiment cooling channels 6a and 6b in platform 2 open out from the entrance to blade cooling channel 5a and travel from the head of the blade along the blade sides 3c and 3d and exit through the edge 3e near the tail of the blade. This structure diverts a portion of the cooling air 4a entering the blade 3 from the cooling channel in base 1 in order to cool platform 2. Alternatively or in addition, at least one of the following types of cooling passages may be provided: (a) cooling air channels 7, which extend from enclosed air space 11 below platform 2 to the upper surface of the platform; (b) convection cooling channels 8 which extend from the leading edge of the platform to the upper surface of the platform at the front or rear side of the blade, and/or (c) air channels 9 which extend on the rear of the turbine blade obliquely from the underside of the platform to the trailing edge of the platform. These various channels or combinations thereof constitute a cooling structure through which air can flow to cool a platform for the drive blades of a gas turbine in an efficient and effective manner.