An axial flow turbine provided with a stage composed of a turbine nozzle and a turbine rotor blade arranged in an axial flow direction. Both end portions of a nozzle blade of the turbine nozzle are supported by a diaphragm inner ring and a diaphragm outer ring, and a flow passage is formed to have its diameter expanded from an upstream stage to a downstream stage. In such axial flow turbine, trailing edges at ends of the nozzle blade supported by the diaphragm inner ring and the diaphragm outer ring are curved as a curvature to an outlet side, and an intermediate portion between the trailing edges is formed to be straight.

Axial flow turbine

According to one aspect of the invention, an exhaust gas diffuser (200) includes an outer casing (202) disposed about a center line (205) of the exhaust gas diffuser (200), a hub (204) disposed about the center line (205), and an end portion (214) of the hub (204) comprises a recess (216) configured to cause a flow of exhaust gas toward the center line (205) as the exhaust gas flows in a downstream direction (207).

Exhaust gas diffuser

A gas turbine including an exhaust diffuser with a flow splitter located between the inner wall and outer wall defining the exhaust gas flow path. In one aspect the flow splitter being moveable independent of the walls defining the exhaust gas flow path to allow for differing thermal movement between the components. In one form a structural member extends from a wall and is coupled to the flow splitter. The wall can have an opening for the through which the structural member is allowed to pass. In some forms a plurality of structural members can be coupled to the flow splitter. In other forms the flow splitter can be independently movable relative to the wall.

Gas turbine exhaust diffuser

A vorticity reducing cowling for a diffuser augmented wind turbine assembly is provided. The diffuser augmented wind turbine assembly includes a shroud, a wind turbine disposed within the shroud, and a diffuser coupled to an outlet of the shroud. The wind turbine includes a wind turbine housing and a plurality of blades rotatably disposed within the wind turbine housing, wherein the plurality of blades providing a swept area. The cowling comprises a body disposed upstream of the plurality of blades. The body includes an inlet end defining a first opening, the first opening having a first area. The body includes an outlet end defining a second opening, the second opening having a second area that is less that the first area. The second area is less than the swept area of the plurality of the blades.

Vorticity reducing cowling for a diffuser augmented wind turbine assembly

In one aspect, an exhaust diffuser for a gas turbine is disclosed. The exhaust diffuser may generally include an inner casing and an outer casing spaced radially apart from the inner casing so as to define a passage for receiving exhaust gases of the gas turbine. Additionally, the exhaust diffuser may include a fluid outlet configured to inject a fluid into the exhaust gases flowing through the passage.

System and method for a gas turbine exhaust diffuser

An axial-flow turbine has an exhaust diffuser including a hub-side tube and a tip-side tube. In the exhaust diffuser, front struts and rear struts are placed to cross a flow of working fluid. A wake generated behind the front strut diverts from the rear strut and passes through a gap between a pair of the rear struts. Otherwise, a wake generated behind the front strut hits against the front face of the rear strut. The front struts are equal to or multiple of the rear struts in number.

Exhaust diffuser for axial-flow turbine

To reduce secondary flow loss and to improved turbine efficiency, a section located radially outward of a border section 28 of a stationary blade 21 is bent in the rotational direction of a rotor. Thus, even if combustion gas leaks from a tip clearance between an end wall of a casing and a tip portion of a rotor blade, and a stagnation line 35 near a tip portion 22 is situated in the side of a back surface 24, because a section located radially outward of the border section 28 is bent in the rotational direction of the rotor, the stagnation line 35 is also situated toward the rotational direction of the rotor. Therefore, the stagnation lines 35 formed at various heights in the heightwise direction of the stationary blade 21 are generally aligned in the rotational direction of the rotor. Thus, fluctuation of pressure distribution in the heightwise direction of the stationary blade 21, of the combustion gas flowing into the stationary blade 21 can be reduced. As a result, secondary flow loss can be reduced and turbine efficiency can be improved.

Blade structure of gas turbine

CFD analysis of industrial gas turbine exhaust diffuser was carried out. Purposes of this study are improvement of the performance of exhaust diffuser in consideration of the distortion of the flow of the turbine exit, improvement of the diffuser performance in the big flow rate, and verification of CFD accuracy. To simulate the diffuser inlet distortion, CFD and experiment was carried out including last stator and rotor. Predicted turbine exit flow and diffuser pressure recovery is in reasonable good agreement with the measured data.

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CFD Studies of Industrial Gas Turbine Exhaust Diffusers

PROBLEM TO BE SOLVED: To enhance exhaust performance by improving a structure and shape of a strut in an exhaust diffuser for an axial turbine. SOLUTION: An axial turbine 1 has an exhaust diffuser 16 made up of a hub side tube 17 and a chip side tube 18. The upstream strut 20 and downstream strut 21 are arranged in the exhaust diffuser 16 so as to cross a flow of the operation fluid. A rear flow generated behind the upstream strut 20 departs from the downstream strut 21 and passes through the space between the downstream struts 21. COPYRIGHT: (C)2006,JPO&NCIPI

Exhaust diffuser for axial turbine

The blade body of the present invention is provided with a main body which has a dorsal face and a ventral face and also provided with a trailing edge portion which connects the dorsal face to the ventral face with a continuous curved face. The curved face of the trailing edge portion is gradually decreased in curvature radius from one of the dorsal face and the ventral face toward the rear end portion which is positioned most downstream in a direction at which a fluid flows, decreased to the greatest extent in curvature radius at the rear end portion, thereafter, gradually increased in curvature radius from the rear end portion toward the other of the dorsal face and the ventral face and arrives at the other of the dorsal face and the ventral face.

Susumu Wakazono

Papers

Exhaust diffuser for axial-flow turbine

Blade structure of gas turbine

CFD Studies of Industrial Gas Turbine Exhaust Diffusers

Exhaust diffuser for axial turbine

Blade body and rotary machine