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Little, David A.

Publications and source records attributed to Little, David A..

Arrangement for a gas turbine combustion engine

An arrangement (10) for delivering gases from combustors (15) to a first row of blades. The arrangement (10) includes at least an upstream flow path (60) including an aft first side wall (64) and a downstream flow path (62) including a forward second side wall (66). A convergence junction trailing edge (40) is defined at a downstream terminal edge (41) of the first side wall (64), and the second side wall (66) converges toward the first side wall (64) in the direction of the convergence junction trailing edge (40). An impingement sheet structure (78) is located between and provides impingement cooling air to the first and second side walls (64, 66). Openings (88) provide a cooling air passage between the first and second side walls (64, 66) and provide a flow of post impingement air into the gas path at the convergence junction trailing edge (40).

33 ADVANCED PROPULSION SYSTEMS↗

Impingement cooling arrangement having a snap-in plate

A cooling arrangement (100), including: a substrate having a pocket (24) defined by a rib side surface (28) and a bottom surface (26); a feature (112) formed in the rib side surface; and an impingement plate (102). In an installed configuration (116) a resilience of the impingement plate enables an interference between the impingement plate and the feature that locks the impingement plate in an installed position (118). An elastic compression of the impingement plate from the installed configuration eliminates the interference.

42 ENGINEERING↗

Mid-section of a can-annular gas turbine engine with a radial air flow discharged from the compressor section

A midframe portion (213) of a gas turbine engine (210) is presented, and includes a compressor section (212) configured to discharge an air flow (211) directed in a radial direction from an outlet of the compressor section (212). Additionally, the midframe portion (213) includes a manifold (214) to directly couple the air flow (211) from the compressor section (212) outlet to an inlet of a respective combustor head (218) of the midframe portion (213).

33 ADVANCED PROPULSION SYSTEMS↗

Casing for a gas turbine engine

A casing for a can annular gas turbine engine, including: a compressed air section (40) spanning between a last row of compressor blades (26) and a first row of turbine blades (28), the compressed air section (40) having a plurality of openings (50) there through, wherein a single combustor/advanced duct assembly (64) extends through each opening (50); and one top hat (68) associated with each opening (50) configured to enclose the associated combustor/advanced duct assembly (64) and seal the opening (50). A volume enclosed by the compressed air section (40) is not greater than a volume of a frustum (54) defined at an upstream end (56) by an inner diameter of the casing at the last row of compressor blades (26) and at a downstream end (60) by an inner diameter of the casing at the first row of turbine blades (28).

33 ADVANCED PROPULSION SYSTEMS↗

Assembly for directing combustion gas

An arrangement is provided for delivering gases from a plurality of combustors of a can-annular gas turbine combustion engine to a first row of turbine blades including a first row of turbine blades. The arrangement includes a gas path cylinder, a cone and an integrated exit piece (IEP) for each combustor. Each IEP comprises an inlet chamber for receiving a gas flow from a respective combustor, and includes a connection segment. The IEPs are connected together to define an annular chamber extending circumferentially and concentric to an engine longitudinal axis, for delivering the gas flow to the first row of blades. A radiused joint extends radially inward from a radially outer side of the inlet chamber to an outer boundary of the annular chamber, and a flared fillet extends radially inward from a radially inner side of the inlet chamber to an inner boundary of the annular chamber.

33 ADVANCED PROPULSION SYSTEMS↗

Mid-section of a can-annular gas turbine engine with an improved rotation of air flow from the compressor to the turbine

A midframe portion (313) of a gas turbine engine (310) is presented and includes a compressor section with a last stage blade to orient an air flow (311) at a first angle (372). The midframe portion (313) further includes a turbine section with a first stage blade to receive the air flow (311) oriented at a second angle (374). The midframe portion (313) further includes a manifold (314) to directly couple the air flow (311) from the compressor section to a combustor head (318) upstream of the turbine section. The combustor head (318) introduces an offset angle in the air flow (311) from the first angle (372) to the second angle (374) to discharge the air flow (311) from the combustor head (318) at the second angle (374). While introducing the offset angle, the combustor head (318) at least maintains or augments the first angle (372).

33 ADVANCED PROPULSION SYSTEMS↗

Compressor airfoil tip clearance optimization system

A compressor airfoil tip clearance optimization system for reducing a gap between a tip of a compressor airfoil and a radially adjacent component of a turbine engine is disclosed. The turbine engine may include ID and OD flowpath boundaries configured to minimize compressor airfoil tip clearances during turbine engine operation in cooperation with one or more clearance reduction systems that are configured to move the rotor assembly axially to reduce tip clearance. The configurations of the ID and OD flowpath boundaries enhance the effectiveness of the axial movement of the rotor assembly, which includes movement of the ID flowpath boundary. During operation of the turbine engine, the rotor assembly may be moved axially to increase the efficiency of the turbine engine.

33 ADVANCED PROPULSION SYSTEMS↗