Low thermal stress ceramic turbine nozzle

A turbine nozzle vane assembly comprising:

• an outer shroud defining an inner surface;
• an inner shroud positioned radially within said outer shroud and defining a first end, a second end, an inner surface and an outer surface;
• a plurality of nozzle vanes being interposed the inner surface of the outer shroud and the outer surface of the inner shroud;
• a slot being positioned in each of the plurality of nozzle vanes, said slot having a length extending axially between the inner surface of the outer shroud and the outer surface of the inner shroud;
• a plurality of bosses being attached to the inner surface of the inner shroud intermediate said first end and said second end, each of said plurality of bosses having a generally rectangular cross-sectional configuration defining a plurality of sides;
• and
• a cylindrical member being positioned radially inwardly of the inner shroud, said cylindrical member including a first side, a second side, an outer surface defining a plurality of steps thereon and a plurality of grooves extending intermediate the first side and the second side corresponding in positional relationship to the plurality of bosses and having said plurality of bosses positioned in at least a portion of the plurality of grooves, said cylindrical member has a plurality of holes extending therethrough and a plurality of pins being positioned in corresponding ones of the plurality of through holes.

A turbine nozzle vane assembly comprising:

• an outer shroud defining an inner surface;
• an inner shroud positioned radially within said outer shroud and defining a first end, a second end, an inner surface and an outer surface;
• a plurality of nozzle vanes being interposed the inner surface of the outer shroud and the outer surface of the inner shroud, each of said plurality of vanes include a leading edge portion, a trailing edge portion, a concave side, a convex side and each of said plurality of vanes have a first gallery and a second gallery therein and said concave side has an opening positioned therein being in communication with the first gallery and said convex side has said slot positioned therein;
• and
• a slot being positioned in each of the plurality of nozzle vanes, said slot having a length extending axially between the inner surface of the outer shroud and the outer surface of the inner shroud.

A turbine nozzle vane assembly comprising:

• an outer shroud defining an inner surface;
• an inner shroud positioned radially within said outer shroud and defining an outer surface;
• a plurality of nozzle vanes defining a first end portion being attached to the inner surface of the outer shroud, a second end portion being attached to the outer surface of,the inner shroud and a center portion defined between the first end portion and the second end portion;
• means for heating said first end portion and said second end portion;
• and
• means for cooling said center portion.