The present invention relates to a compressor stage for a gas turbine, in particular, an aircraft engine, having a row of rotating blades (3) and a row of guide vanes (4), which is adjacent downstream, wherein the choke point and the aspect ratio AR.sub.ax, which is defined by the quotient between average channel height (h) and average chord length (l.sub.ax), satisfy the condition
>1.33.Math.AR.sub.ax+5.16.

Methods and apparatus are provided for an axi-centrifugal compressor in a gas turbine engine for a business aviation or rotorcraft propulsion unit. The compressor includes an axial compressor section operable to affect a first pressure ratio along the flow path between a compressor inlet and a first section exit, and a centrifugal compressor section operable to affect a second pressure ratio along the flow path between a second section inlet and the compressor exit. The pressure rise across the axial and centrifugal compressor section is configured to have a tuning factor is in a range between 2.8 and 4.5 and a loading factor in a range between 0.6 and 0.8.

Blowers, e.g., for use in outdoor applications, are provided. A blower includes an air inlet; an air outlet; and a fan assembly disposed between the air inlet and the air outlet. The fan assembly has a three-stage fan. The three-stage fan includes three axial fans mounted on a drive shaft and three stator fans arranged in series with the axial fans, wherein each axial fan comprises a plurality of blades each having a blade tip. The three-stage fan has a dimensionless flow coefficient ? in a range from about 0.3 to 0.5 as calculated by the equation ?=(q/(A))/?R where q represents flow (m.sup.3/s), A represents cross sectional area at the fan (m.sup.2), ? represents speed (rad/s) and R represents fan tip radius (m) measured at a blade tip.

A fan system includes a rotor having plurality of blades and a ring airfoil, the plurality of blades being rotatably joined to a hub and the ring airfoil. The fan system may include a second contra-rotationally disposed rotor having a plurality of blades and a ring airfoil. The first and second ring airfoils having a cambered shape and an angle of attack between about ?5 degrees and about 45 degrees, more preferably between about 5 degrees and about 30 degrees. Optionally, an outlet guide vane may be mounted rearward of the one or more rotors having a ring airfoil.

The LNG plant comprises a compression train and a further compression. The compression train (100) comprises comprising an engine and a compressor driven by the engine; the compressor is an axial compressor and comprises a first set of axial compression stages and a second set of axial compression stages arranged downstream the first set of axial compression stages; at least the first set and the second set of axial compression stages are housed inside one case. The further compression train comprises a further engine and a further compressor driven by the further engine; the further compressor is a centrifugal compressor and comprises a first set of impellers and a second set of impellers arranged downstream or upstream the first set of impellers.

The invention relates to a compressor for an engine, wherein the compressor has compressor stages arranged in succession in a flow direction of the compressor and each compressor stage has a rotating blade cascade and a guide vane cascade arranged downstream of the rotating blade cascade and the rotating blade cascade and the guide vane cascade each have an aspect ratio.

A fluid flow machine, includes a main flow path formed by a hub and a housing, an arrangement of rotating blades in the main flow path to supply energy to the fluid, forming a rotor assembly group, an arrangement of resting blades arranged adjacent to the rotor in the main flow path, forming a stator assembly group, wherein respectively one rotor assembly group and one stator assembly group adjacent thereto form a stage of the fluid flow machine. In at least one stage, the averaged blade profile angles .sub.RI, .sub.RE of the rotor assembly group, the averaged blade profile angles .sub.SI, .sub.SE of the stator assembly group, as well as the course of the cross-sectional areas of the main flow path in a downstream direction are selected such that they fulfill a certain relationship to increase the realizable level of efficient work to be supplied.

An axial compressor of a fluid-flow machine includes a flow path disposed between a rotor shaft and a relatively stationary housing wall. The flow path extends in an axial direction of the rotor shaft concentrically with the rotor shaft and the housing wall. A plurality of compressor stages are axially arranged in sequence along the flow path in the axial direction. Each of the compressor stages includes a rotor blades row and a guide vane row disposed after the rotor blades row in the axial direction. The flow path and the compressor stages operating therein are penetrable by a mass flow of a fluid to be compressed in a flow direction during operation of the compressor. A return is configured to return a part of the mass flow from a compressor discharge.

A gas turbine engine comprises a high pressure turbine rotor, an intermediate pressure turbine rotor and a fan drive turbine rotor. The fan drive turbine rotor drives a fan rotor through a gear reduction. The intermediate pressure rotor drives a low pressure compressor rotor and the high pressure turbine rotor drives a high pressure compressor rotor. A first flow cross-sectional area is between an outer periphery of a hub in the low pressure compressor rotor, and an outer tip of an upstream most blade row of the low pressure compressor rotor. A second flow cross-sectional area is between an outer periphery of a hub in the high pressure compressor rotor, and an outer tip of an upstream most blade row of the high pressure compressor rotor. A ratio of the first and second flow cross-sectional areas is greater than or equal to about 0.12 and less than or equal to about 0.33.

Blowers, e.g., for use in outdoor applications, are provided. A blower includes an air inlet; an air outlet; and a fan assembly disposed between the air inlet and the air outlet. The fan assembly has a three-stage fan. The three-stage fan includes three axial fans mounted on a drive shaft and three stator fans arranged in series with the axial fans, wherein each axial fan comprises a plurality of blades each having a blade tip. The three-stage fan has a dimensionless flow coefficient in a range from about 0.3 to 0.5 as calculated by the equation =(q/(A))/R where q represents flow (m.sup.3/s), A represents cross sectional area at the fan (m.sup.2), represents speed (rad/s) and R represents fan tip radius (m) measured at a blade tip.