Low pressure end diffuser for axial flow elastic fluid turbines

Claim 2

In the low pressure end of an axial flow elastic fluid turbine including a diffuser spaced with respect to the last stage turbine blades to provide an annular shaped exhaust outlet, with the diffuser being formed by a fairing structure, the improvement in the diffuser comprising: a housing fixed to the outer surface of the fairing structure to define a chamber having at least a portion thereof disposed downstream of the trailing edges of the last stage turbine blades, means defining at least one opening between said chamber and a location upstream of the last stage turbine blades, said fairing structure having injection slots communcating between said chamber and said exhaust outlet downstream of the trailing edges of the last stage turbine blades and positioned such that fluid will flow from said chamber downstream along at least a major portion of the inner surface of said outer fairing structure, and said housing having additional means for venting heavily ladened moisture fluid from said chamber.

Claim 3

The improvement as set forth in claim 1, wherein said housing is a continuous annular member fixed to the outer surface of said fairing structure to define a single chamber.

Claim 4

The improvement as set forth in claim 1, wherein each of said injection slots is shaped to have a discharge opening generally tangential to the inner surface of said fairing structure.

Claim 5

The improvement as set forth in claim 1, wherein said fairing structure has arcuately spaced openings communicating between said chamber and an annular space, adjacent the leading edges of the last stage turbine blades.

Claim 6

An axial flow elastic fluid turbine having a tubular shell structure defining an axially extending elastic fluid passage, a rotor centrally disposed in said passage and having at least one annular row of turbine blades, means for directing fluid flow onto said turbine blades, said tubular shell structure including outer and inner shells, said outer shell including an annular exhaust hood structure having a centrally disposed fairing member, said inner shell including a centrally disposed fairing member spaced from and cooperating with the fairing member of said outer shell to define an annular shaped exhaust outlet for passage of fluid flow from the last stAge turbine blades, a housing fixed to the outer surface of the inner shell fairing member to define a chamber having at least a portion thereof disposed downstream of the trailing edges of the last stage turbine blades, means defining at least one opening between said chamber and a location upstream of the last stage turbine blades, said inner shell fairing member having injection slots communicating between said chamber and said exhaust outlet downstream of the trailing edges of the last stage turbine blades and positioned such that fluid will flow from said chamber in a downstream direction along at least a major portion of the inner surface of said inner shell fairing member, and said housing having vent opening means formed therethrough for discharging heavily ladened moisture fluid from said chamber.

Claim 7

An axial flow elastic fluid turbine having a tubular shell structure defining an axially extending elastic fluid passage, a rotor centrally disposed in said passage and having at least one annular row of turbine blades, means for directing fluid flow onto said turbine blades, said tubular shell structure including outer and inner shells, said outer shell including an annular exhaust hood structure having a centrally disposed fairing member, said inner shell including a centrally disposed fairing member spaced from and cooperating with the fairing member of said outer shell to define an annular shaped exhaust outlet for passage of fluid flow from the last stAge turbine blades, a housing fixed to the outer surface of the inner shell fairing member to define a chamber having at least a portion thereof disposed downstream of the trailing edges of the last stage turbine blades, means defining at least one opening between said chamber and a location upstream of the last stage turbine blades, said inner shell fairing member having injection slots communicating between said chamber and said exhaust outlet downstream of the trailing edges of the last stage turbine blades and positioned such that fluid will flow from said chamber in a downstream direction along at least a major portion of the inner surface of said inner shell fairing member, and said housing having vent opening means formed therethrough for discharging heavily ladened moisture fluid from said chamber.

Claim 8

The turbine as set forth in claim 5 wherein each of said injection slots is shaped to have a discharge opening generally tangential to the inner surface of said inner shell fairing member.

Claim 9

The turbine as set forth in claim 5 wherein said housing means is a continuous annular member fixed to the outer surface of said inner shell fairing member to define a single chamber.

Claim 10

The turbine as set forth in claim 5 wherein said inner shell is arranged to define an annular passageway disposed in a plane generally transverse to the axis of said rotor and adjacent the leading edges of the last stage turbine blades; and wherein said opening communicates between said passageway and said chamber.