Abstract: Void structures, systems and devices with void structures, and methods of fabricating void structures are disclosed. A void structure is disclosed with a repeating elongated-aperture pattern designed to provide negative Poisson's Ratio behavior under macroscopic stress and strain loading. The pattern can include horizontal and vertical elliptically shaped apertures that are arranged on horizontal and vertical lines in a way that the lines are equally spaced in both dimensions. The centers of each aperture is on a crossing point of two of the lines. The vertical and horizontal elliptically shaped apertures alternate on the vertical and horizontal lines such that any vertical aperture is surrounded by horizontal apertures along the lines (and vice versa), and the next vertical apertures are found on both diagonals. The voids can also act as cooling and/or damping holes and, due to their arrangement, also as stress reduction features.

Abstract: An auxetic locking structure can be used as a mechanism for securing two or more members in an assembly or other system. The locking structure has void patterns on its exterior surface which permit the locking structure to reduce its outer diameter upon loading in an axial direction. Once the structure has been sufficiently loaded and the diameter has been sufficiently reduced, the locking structure may be positioned within a bore of an article, the axial load is then reduced, thus causing the locking structure to expand and engage the bore of the article. The locking structure and article are now secured to one another creating an improved assembly.

Abstract: A gas turbine engine combustion system including a mixing duct that separates into at least two branch passages for the delivery of a fuel and working fluid to distinct locations within a combustion chamber. The residence time for the fuel and working fluid within each of the two branch passages is distinct.

Abstract: A combustion chamber may include a first surface and a second surface interconnected by a wall forming a chamber having a central axis. The first surface may define an exhaust opening and the second surface defining a pilot opening, wherein the exhaust opening and the pilot opening align along the central axis. A plurality of inlet ports may be configured to deliver air to the chamber. A plurality of fuel ports may be arranged on an inside of the second surface to deliver fuel to the chamber. The air flow from the inlet ports and fuel from the fuel ports may oppose each other to create a vortex of product proximal to the second surface.

Abstract: An auxetic locking structure can be used as a mechanism for securing two or more members in an assembly or other system. The locking structure has void patterns on its exterior surface which permit the locking structure to reduce its outer diameter upon loading in an axial direction. Once the structure has been sufficiently loaded and the diameter has been sufficiently reduced, the locking structure may be positioned within a bore of an article, the axial load is then reduced, thus causing the locking structure to expand and engage the bore of the article. The locking structure and article are now secured to one another creating an improved assembly.

Abstract: A material which exhibits auxetic characteristics and control of thermal expansion characteristics while experiencing significant stress reduction is disclosed. The material has a repeating pattern of void structures along both lateral symmetry lines and longitudinal symmetry lines.

Abstract: A method of modulating the cooling of a gas turbine component is disclosed. The method includes determining a target component temperature at which the gas turbine component can be maintained without the gas turbine component experiencing a failure over the course of an indicated life of the gas turbine component; scheduling a cooling air value to the target component temperature; and determining one or more of a demanded cooling air temperature and a demanded cooling air mass flow rate based on the scheduled cooling air value.

Abstract: A method of assembling a gas turbine engine comprising the steps of providing a casing having an insertion aperture in its outer surface. A guide vane is inserted through the insertion aperture. The guide vane is secured to the outer surface of the casing such that the guide vane can be serviced from an outer part of the casing.

Abstract: One example of a gas turbine engine may include a gas generator, a reheat combustor that is disposed downstream of the gas generator, and a power turbine that is disposed downstream of the reheat combustor and includes a plurality of nozzle guide vanes. The reheat combustor is configured to increase a fuel flow so as to increase a temperature of the reheat combustor and match a required exhaust temperature. The nozzle guide vanes are configured to increase a real capacity at a power turbine inlet in proportion with the required exhaust temperature. A constant apparent capacity at a gas generator exit upstream of the reheat combustor remains constant, in response to proportionately increasing the temperature and the real capacity with respect to one another.

Abstract: One example of a gas turbine engine can include a first compressor and a first turbine connected to the first compressor by a first shaft. The engine can include a reheat combustor, which is disposed downstream of the first turbine, and a second turbine, which is disposed downstream of the reheat combustor. The engine can further include a second compressor, which is connected to the second turbine by a second shaft and is disposed upstream of the first compressor. The first and second turbines can be disconnected from one another, and the first and second compressors can be disconnected from one another. The second compressor may have an outlet including a flow to the first compressor, such that the first and second turbines provide a shaft worksplit. The reheat combustor can be configured to receive fuel and generate a reheat exit temperature, so as to control an apparent capacity of the second turbine based on a plurality of parameters of the second compressor.

Abstract: A combustion chamber device having a field static pressure gradient adapted to expel a flame kernel or hot spot from a fuel-air mixing duct. The swirling flow passing through an annular mixing duct is turned from a radial direction to an axial direction before entering the combustion chamber. An ignition source located within the fuel-air mixing duct can then be used to start the combustion process in the gas turbine.

Abstract: A combustion chamber device having a field static pressure gradient adapted to expel a flame kernel or hot spot from a fuel-air mixing duct. The swirling flow passing through an annular mixing duct is turned from a radial direction to an axial direction before entering the combustion chamber. An ignition source located within the fuel-air mixing duct can then be used to start the combustion process in the gas turbine.

Abstract: A system for actively controlling the working line location within a low pressure compressor. The system includes a plurality of variable inlet guide vanes that are adjusted to maintain the working line at a constant level as the low pressure compressor rotates at a constant speed.