摘要:
A method of fabricating an annular liner for a combustion chamber of a gas turbine engine. The combustion chamber has a dome including a fuel nozzle for delivering fuel to the combustion chamber. A metal piece is formed into an annular section constituting at least a portion of the liner and having at least one seam extending generally axially with respect to an axial centerline of the liner. An upstream end of the liner is machined to have a registration feature for connecting the liner to the combustion chamber dome in at least one predetermined orientation with respect to the dome. Further, the method includes ensuring the registration feature and the seam are located relative to each other on the liner so the seam is at a preselected position with respect to the combustion chamber dome when the liner is connected to the combustion chamber dome in the predetermined orientation.
摘要:
A gas turbine engine includes a combustor system including a lean premix combustor and a water delivery system. The combustor is operable with a fuel/air mixture equivalence ratio less than one and the water delivery system is configured to supply at least one of water or steam to the gas turbine engine such that either the water or the steam is injected into the combustor to control emissions generated by the combustor. As a result, nitrous oxide emissions for specified turbine operating power levels are lowered.
摘要:
Multi-hole film cooling of combustor liners is enhanced by providing clustered groups of cooling holes in areas of the liners that would otherwise experience a loss of cooling film effectiveness. The combustor liner is made up of a shell having first and second groups of cooling holes formed therein. The cooling holes of the second group are more closely spaced than the cooling holes of the first group. The second group of cooling holes is located on an area of the shell where the cooling film effectiveness is degraded. Preferred locations include a region of the shell that is subjected to swirl impingement and a spot immediately downstream of a large opening in the shell such as a dilution hole, a borescope hole or an igniter port hole.
摘要:
An acousto-optic device which is incorporated into a fiber optic system to define, based upon device configuration, an element such as a phase modulator, optical tap, frequency shifter or mode coupler. The device comprises an acoustic transmission member having a groove therein which is secured in the Hertzian contact along a continuous portion of its surface with an optical waveguide so as to communicate acoustic signals from a transducer affixed on the member through the Hertzian contact area and into the optical waveguide. In one preferred embodiment the member comprises a capillary tube having a bore that is substantially the same diameter as the optical waveguide to which the device is to be affixed. A portion of the capillary tube is removed to expose the base, thereby defining a groove along the capillary substrate. In one preferred embodiment an acoustic transducer is deposited on the curved surface opposite the groove to focus acoustic signals from the transducer toward the groove. In another preferred embodiment, a portion of the capillary substrate opposite the groove is lapped to form a substantially flat surface which is parallel to the plane of the groove. An acoustic transducer is then deposited on the flat surface. The capillary substrate may also be lapped to form a wedge configuration for launching acoustic waves at an angle with respect to the groove. The optical waveguide is pressed into the groove to form the Hertzian contact with the groove.
摘要:
A system and method for quantum key delivery in a single-photon, free-space cryptography scheme including a transmitter and a receiver. The transmitter includes two pairs of photon sources, each of which represents a specific photon polarization direction. The first pair of photon sources represents a first polarization basis while the remaining pair of photon sources represents a second polarization basis. The first and second polarization basis are rotated with respect to each other so as to produce non-orthogonal polarization eigenstates. A transmitter polarizing beamsplitter corresponding to each of the pairs of the photon sources is provided whereby the polarizations of each of the photon sources of each pair of photon sources are recombined. A transmitter non-polarizing beamsplitter is provided whereby the recombined polarizations are combined for output to the receiver. The receiver includes a set of optics inversely disposed with respect to the optics of the transmitter and two pairs of photon detectors.