Abstract: A stator assembly 20 for a gas turbine engine is disclosed. The stator assembly includes an outer case 22 and an array of stator vanes 32 extending inwardly across an annular flow path 18 for working medium gases. The stator assembly includes a duct 34 which engages the stator vanes and which is trapped between a stator vane and a stator element 38 extending inwardly from the outer case. The duct includes a transition piece 78 which extends axially to shield a portion of the stator vane. In one embodiment the duct includes an extension 80 which extends into proximity with an outer air seal assembly 31 to form a cooling air chamber 36 adjacent to the stator element.

Abstract: A seal means 66 for a blade attachment slot of a rotor assembly 12 is disclosed. Various construction details which adapt the rotor assembly to block the leakage of cooling air from the blade attachment slot 40 as the cooling air is flowed to a rotor blade 22 are developed. In one embodiment, the seal means has a seal plate 68 and baffles 70,72 integral with the seal plate which define a cooling air chamber for receiving cooling air from a passage way 38 in a rotor disk 20. The seal plate extends axially and laterally to block the leakage of cooling air in the radial direction. Baffles extend radially from the plate for blocking the leakage of cooling air in the axial direction.

Abstract: A control valve assembly 10 having a pair of axially opposed seats 54, 56 is disclosed. A poppet 66 is disposed in a control chamber 58 between the seats. The poppet is movable between the seats to establish an average pressure in the control chamber. The poppet is an integral portion of an armature 28. In one embodiment, the armature is urged in a first direction by a solenoid and in the opposite direction by a conical spring 76 which extends between the armature and a housing of the valve. In another embodiment, the armature has a spherical zone 94 on a convex surface 92 and a spring guide 84 engages the spring and has a concave surface which engages the spherical zone. In still another embodiment, means 310, such as diaphragms 312 or 314 or the slidable engagement 318, 320 between the housing 224 and the first end 251 of the armature are provided for radially positioning the armature as the armature is moved between the seats.

Abstract: A rotor assembly 22 for a gas turbine engine is disclosed. The engine has a compression section 12 and a turbine section 16. Various construction details which enable the modular disassembly of the turbine section are developed. The rotor assembly includes a rotor shaft 42 extending between the compression section and the turbine section. An annular shaft 66 engages a bearing 64, is joined to a rotor blade assembly 74, and rotatably supports the rotor shaft 42.

Abstract: An annular beam 46 which is hollow and which extends circumferentially about an annular flow path 22, 24 for working medium gases is disclosed. The annular beam supports and positions both a shroud 42 and a fabric 44 for containing particles having axial and radial velocity. The annular beam has a first wall 48 and a second wall 50. The second wall is spaced radially from the first wall. A plurality of annular plates 52 extending circumferentially about the interior of the beam. The plates are attached to the first wall and to the second wall. In one detailed embodiment the annular plates have a C-shaped cross section formed of a circumferentially extending rib 58 and two axially oriented legs 60, 62. The radial height of the rib is many times greater than the radial height of the legs. A method of fabricating the annular beam is disclosed.

Abstract: A binary electrolyte for a molten carbonate fuel cell is disclosed. The electrolyte is approximately 72 m % Li.sub.2 CO.sub.3 and 28 m % K.sub.2 CO.sub.3 and displays a uniform lithium to potassium in molar ratio during operation along the length of the fuel cell stack.

Abstract: A fixture 34 for positioning a shroud 22 of a worn rotor blade 14 with respect to an apparatus for removing material is disclosed. The fixture is formed of a base 42, an axial locator 44 which is adapted to engage the root 18 of the rotor blade, and a tangential locator 46 which engages the root of the rotor blade at a hinge joint 58 and which engages the airfoil 20 of the rotor blade. A method of restoring a shroud of the rotor blade axially with respect to the root and tangentially with respect to the airfoil is also disclosed. In an alternate embodiment, a second locator 160 for indexing the locator from an airfoil edge is included.

Abstract: An airfoil structure for use in an axial flow turbomachine is disclosed. Various construction details which improve the durability, integrity and the cooling effectiveness of the structure are shown and a method for fabricating the structure is developed. The tip of the structure is closed by a tip cap, and in one embodiment, a ductile material is deposited between the tip of the structure and the tip cap to prevent the leakage of cooling medium.

Abstract: A rotor assembly 10 having a coolable rotor blade 14 for a gas turbine engine is disclosed. Various construction details are discussed which enable the rotor blade to satisfy the aerodynamic requirements of the engine and the requirements of fatigue life for the rotor assembly. The rotor blade includes a spar 38 and a shell 34 which extends chordwisely beyond the root 42 of the spar. In one embodiment, an axis of symmetry A.sub.r of the root of the spar is parallel to the axis of rotation A of the rotor assembly.

Abstract: A cooling system 46 for a turbofan gas turbine engine 10 is disclosed. Various construction details which increase the effectiveness of a heat exchanger 70, 76, 112 are disclosed. In one embodiment, a rotor shaft 98 is used to pressurize buffer air for a bearing compartment 40.

Abstract: A cooling system 24 for an electrochemical cell stack 12 is disclosed. Various construction details which avoid plugging of the cooling system during long term operation with a cooling fluid having dissolved species and suspended particles, such as water, are discussed. The cooling system includes spaced apart cooler assemblies 30. Conduits 32 for supplying cooling fluid to the cooler assemblies include sets of cooling tubes 74 in serial flow communication.

Abstract: An airfoil shaped cross section 36 for the rotor blade 14 is disclosed. Various construction details which improve the aerodynamic and drag performance of the airfoil section are developed. The upper surface 38 and the lower surface 42 are contoured by a thickness distribution and a camber distribution such that the bend of the surfaces is constant or changes at a constant rate over certain regions of the airfoil to avoid the formation of strong, normal shock waves at local Mach numbers less than 1.2 during normal, level flight conditions at standard temperature and pressure.

Abstract: A rotor stage assembly 20 of the type adapted for use in an axial flow gas turbine engine is disclosed. The assembly includes a rotor disk 36, at least two rotor blades 42 and a scalloped lock pin 52. The scalloped lock pin has lugs 54. The disk is adapted by a groove 40 and each blade is adapted by a groove 48 to receive the scalloped lock pin. During assembly the scalloped lock pin is alignable with blade attachment slots 44 in the disk to enable insertion of the blades and is slidable in the grooves 40, 48 to bring each lug 54 on the scalloped pin into engagement with a corresponding groove in a rotor blade.

Abstract: A cooling system 46 for a turbofan gas turbine engine 10 is disclosed. Various construction details which increase the effectiveness of a heat exchanger 70, 76, 112 are disclosed. In one embodiment, a rotor shaft 98 is used to pressurize buffer air for a bearing compartment 40.

Abstract: A stator structure 88 for supporting a pair of outer air seals 62, 72 and an array of stator vanes 82 from two axial locations A.sub.1, A.sub.2 on a coolable outer case is disclosed. Various construction details which enable the structure to respond to the movement of coolable rails are disclosed. In one embodiment, a pair of support rings 96, 100 and a pair of support rings 122, 124 extend between the outer case and the outer air seal and array of stator vanes 82.

Abstract: A latch system 34 for the nacelle cowling 24 of a gas turbine engine 10 is disclosed. The latch system includes a coupling 36 which may be remotely operated by means of a cable 44. In one embodiment, a support structure 14, the coupling, the cable and a linkage system 48 for applying tension to the cable extends circumferentially about the interior of the cowling to provide constricting force on the cowling to increase the structural rigidity of the cowling. In another embodiment, the coupling has jaws 58 and 60 which are movable from a locked to an unlocked position as a result of the relative movement between the jaws and a housing 50. A linkage system is provided for tensioning the cable which in the locked position uses the tension in the cable to resist operative forces which might seek to open the latching system.

Abstract: A cooling system 46 for a turbofan gas turbine 10 is disclosed. Various construction details which increase the effectiveness of a heat exchanger 48 located in the secondary flow path 24 are developed. In one embodiment, the cooled air is used for protecting a bearing compartment.

Abstract: A control valve assembly 10 having a pair of axially opposed seats 54, 56 is disclosed. A poppet 66 is disposed in a control chamber 58 between the seats. The poppet is movable between the seats to establish an average pressure in the control chamber. The poppet is an integral portion of an armature 28. In one embodiment, the armature is urged in a first direction by a solenoid and in the opposite direction by a conical spring 76 which extends between the armature and a housing of the valve. In another embodiment, the armature has a spherical zone 94 on a convex surface 92 and a spring guide 84 engages the spring and has a concave surface which engages the spherical zone.

Abstract: A rotor assembly 20 for a gas turbine engine 10 is disclosed. The rotor assembly includes a pair of axially spaced apart rotor disks such as the rotor disks 32 and 34. An inner air seal 50 extends axially between the adjacent rotor disks. A member 56 extends axially between the disks to join the disks together and is attached to the inner air seal at a mid span location to restrain the seal against outward movement.

Abstract: A stator assembly 20 for a gas turbine engine is disclosed. The stator assembly includes an outer case 22 and an array of stator vanes 32 extending inwardly across an annular flow path 18 for working medium gases. The stator assembly includes a duct 34 which engages the stator vanes and which is trapped between a stator vane and a stator element 38 extending inwardly from the outer case. The duct includes a transition piece 78 which extends axially to shield a portion of the stator vane. In one embodiment the duct includes an extension 80 which extends into proximity with an outer air seal assembly 31 to form a cooling air chamber 36 adjacent to the stator element.