초록 ▼

Turbine stator vane segments have radially inner and outer walls with vanes extending between them. The inner and outer walls are compartmentalized and have impingement plates. Steam flowing into the outer wall plenum passes through the impingement plate for impingement cooling of the outer wall upp

Turbine stator vane segments have radially inner and outer walls with vanes extending between them. The inner and outer walls are compartmentalized and have impingement plates. Steam flowing into the outer wall plenum passes through the impingement plate for impingement cooling of the outer wall upper surface. The spent impingement steam flows into cavities of the vane having inserts for impingement cooling the walls of the vane. The steam passes into the inner wall and through the impingement plate for impingement cooling of the inner wall surface and for return through return cavities having inserts for impingement cooling of the vane surfaces. To provide for air film cooing of select portions of the airfoil outer surface, at least one air pocket is defined on a wall of at least one of the cavities. Each air pocket is substantially closed with respect to the cooling medium in the cavity and cooling air pumped to the air pocket flows through outlet apertures in the wall of the airfoil to cool the same.

대표청구항 ▼

1. A stator vane segment for forming part of a stage of a turbine, comprising:inner and outer walls spaced from one another; a stator vane extending between said inner and outer walls and having leading and trailing edges, said vane including a plurality of discrete cavities between the leading and

1. A stator vane segment for forming part of a stage of a turbine, comprising:inner and outer walls spaced from one another; a stator vane extending between said inner and outer walls and having leading and trailing edges, said vane including a plurality of discrete cavities between the leading and trailing edges and extending lengthwise of said vane for flowing a cooling medium; at least one air pocket defined one of in and along a wall of at least one said cavity, each air pocket being substantially closed with respect to the respective cavity and being in flow communication with a source of cooling air; and at least one outlet aperture for flow communication between an interior of each pocket and an exterior surface of the vane, wherein said plurality of discrete cavities includes a leading cavity, at least one intermediate cavity, and an aft cavity together defining a substantially closed cooling medium flow passage through the vane, and wherein said at least one air pocket is defined along a wall of at least one of said leading and intermediate cavities.