Abstract: A geopolymer material made from principal minerals, which comprises SiO2, Al2O3, Fe2O3, TiO2, and optionally trace amounts of calcium. Also disclosed are cementitious material comprised of the geopolymer and concrete made from mixing the geopolymer cementitious material with an alkaline solution. Methods of making the geopolymer composite as well as methods of making the geopolymer concrete are also disclosed.

Abstract: An impingement box for a turbine shroud. The impingement box may include a first side with an air access aperture positioned therein and a second side with a number of impingement holes positioned therein. The second side may be positioned a predetermined distance above a floor of the shroud such that the impingement holes provide a cooling flow to the floor of the shroud.

Abstract: The dovetails of turbine buckets are received in dovetail grooves between circumferentially adjacent wheelposts on a turbine wheel of a gas turbine rotor. The wheel and a spacer are rabbeted one to the other and an axially forwardly extending projection on each bucket dovetail is undercut to space the bucket projection from the outer rim of the spacer eliminating stress on the bucket from the spacer. A cavity is formed between radially outwardly converging wall portions of the spacer and end faces of the wheelposts and bucket dovetails. An annular seal wire conforms and seals between the spacer wall portions and end faces of the wheelposts and bucket dovetails in response to centrifugal forces during turbine operation.

Abstract: Arcuate seal layers conforming with one another are disposed between inner retainer segments and inner rails of nozzle segments of a gas turbine. The layers are secured to the aft axial face of the segments and project radially outwardly to seal against the forward axial faces of the rails. The rear axial faces of the rails have chordal seals for sealing against the forward axial faces of the support rings. The seal layers have radial cuts misaligned with one another in an axial direction to preclude leakage flows through gaps formed by the cuts. Arcuate spacers are staggered circumferentially with the arcuate retainer segments whereby an intermediate pressure plenum is formed between the finger seals and chordal seals.

Abstract: The dovetails of turbine buckets are received in dovetail grooves between circumferentially adjacent wheelposts on a turbine wheel of a gas turbine rotor. The wheel and a spacer are rabbeted one to the other and an axially forwardly extending projection on each bucket dovetail is undercut to space the bucket projection from. the outer rim of the spacer eliminating stress on the bucket from the spacer. A cavity is formed between radially outwardly converging wall portions of the spacer and end faces of the wheelposts and bucket dovetails. An annular seal wire conforms and seals between the spacer wall portions and end faces of the wheelposts and bucket dovetails in response to centrifugal forces during turbine operation.