A circular row of non-uniformally spaced vanes includes only one first group and only one second group of adjacent vanes, unequal first and second spacing between adjacent vanes in the first and second groups, and first spacing greater than second spacing. An embodiment with second group including only three adjacent vanes. Second spacing may be about 25%-35% smaller than a nominal uniform spacing used as a design parameter for designing spacing of the non-uniformly spaced stator vanes. Circular row may be sectored. A gas turbine engine section may include one or more rings or circular rows of fixed and/or variable non-uniformally spaced vanes. Method for designing non-uniform vane spacing for circular row includes determining nominal uniform spacing and forming first spacing and second spacing from nominal uniform spacing of vanes.

A heat exchanger for a ducted fan gas turbine engine has a low temperature side and plural high temperature sides. The heat exchanger is configured such that heat is extracted from respective engine fluids flowing through the high temperature sides and is received by a portion of a bypass airflow of the engine which, on passing through the fan duct, is diverted through the low temperature side of the heat exchanger thereby cooling the engine fluids.

A turbine engine includes a first compressor and a second compressor fluidly parallel to the first compressor. A reverse flow combustor is fluidly connected to the first compressor and the second compressor. A first turbine and a second turbine are fluidly connected in series, and fluidly connected to an output of the reverse flow combustor.

An unducted thrust producing system, includes a rotating element, a stationary element. An inlet may be located forward or aft of the rotating element and the stationary element. An exhaust may be located forward, aft, or between the rotating element and the stationary element.

A method of manufacturing a gas turbine engine including designing a row of vanes provided upstream of an asymmetric gas flow volume. The method includes two dimensionally optimizing camberline and stagger angle of each vane, including using orthogonal polynomials to modify the camberline and stagger angle of each vane.

The gas turbine engine includes a core engine, a low pressure turbine, a fan assembly, a gearbox, and a lubrication scavenge pump. The core engine includes a high pressure compressor, a combustor, and a high pressure turbine configured in a serial flow arrangement. The low pressure turbine is positioned axially aft of the core engine. The fan assembly is positioned axially forward of the core engine. The gearbox is positioned axially forward of the fan assembly. The lubrication scavenge pump is positioned forward of the gearbox.

The present invention relates to a method for designing a flow channel for a turbomachine, in particular a gas turbine that comprises a guide vane cascade having a plurality of guide vanes, which are distributed in the peripheral direction, and flow passages, each of which is bounded by two successive guide vanes, and a support rib arrangement having at least one support rib, wherein a design of one of the flow passages is adapted to this support rib, that it is situated downstream of, in order to reduce a pressure loss and/or a vibrational stimulation.

A pre-exit thrust reverser includes an upper reverser door pivotally mounted to a frame and having an upper trailing edge, a lower reverser door pivotally mounted to the frame and having a lower trailing edge and an exhaust duct fixedly mounted to the frame. The upper trailing edge is configured to extend aft of the lower trailing edge when the thrust reverser assumes a deployed state.

A propulsion system is provided including an unducted rotating fan defining a fan axis; and a turbomachine disposed downstream from the unducted rotating fan, wherein the turbomachine defines a working gas flowpath flowing therethrough; wherein the propulsion system defines a third stream flowpath and an inlet passage having an inlet that is offset from the fan axis, wherein the inlet passage is configured to provide an inlet airflow to the working gas flowpath, and wherein the third stream flowpath bypasses at least a portion of the turbomachine.

A gas turbine engine includes a very high speed low pressure turbine such that a quantity defined by the exit area of the low pressure turbine multiplied by the square of the low pressure turbine rotational speed compared to the same parameters for the high pressure turbine is at a ratio between about 0.5 and about 1.5.