Patent US3876330A successfully refreshed from Google Patents.
US3876330A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotor blades for fluid flow machines
Assignee: Rolls Royce PLC
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Filing: 1973-04-19
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Granted: 1975-04-08
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Expires: 1993-04-19
Abstract
Abstract This invention has the object of improving the efficiency of fluid flow machines generally, and particularly the specific fuel consumption of gas turbine engines. The invention comprises a fluid-flow deflector member for a rotor blade, which projects outwardly from the radially outer end of the blade into the region of leakage fluid flow in the clearance between the machine casing and the blade. The fluid-deflector member has a fluiddeflecting surface which is oriented generally transversely of the direction of blade rotation and which faces the upstream direction. An exchange of momentum occurs between the flow of leakage fluid and the deflector surface, and the deflector member thus transmits a force to the blade acting in the direction of blade rotation. If desired, the deflector member can also be positioned to extract momentum from blade cooling fluid ejected from the radially outer end of the blade, thus further augmenting rotor torque and increasing machine efficiency.
Inventors
- 👤 Harry Pearson
- 👤 Lawrence John Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:05
CPC Classifications
F; F01; F01D; F01D5/00; F01D5/12; F01D5/14; F01D5/18; F01D5/20; F01D5/22; F01D5/225; F05; F05D; F05D2240/00; F05D2240/80; F05D2240/81
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
136 words
An axial flow turbine rotor blade having a shroud at its radially outer end and a fluid deflecting member projecting outwardly of the radially outer suface of said shroud into the region of leakage fluid flow between the high and low pressure sides of the shroud, said fluid deflecting member possessing a substantially fin-shaped fluid-deflecting surface which over at least the greater part of its area is oriented transversely of the direction of rotation of said blade, but not normal thereto, and faces towards both the high pressure side of the shroud and the trailing edge of the shroud, thereby to deflect at least a portion of said leakage flow and exchange momentum therewith, a force acting in the direction of blade rotation thereby being produced on said member to assist the rotation of said blade.
Claim 2
Dependent Claim
136 words
An axial flow turbine rotor blade having a shroud at its radially outer end and a fluid deflecting member projecting outwardly of the radially outer suface of said shroud into the region of leakage fluid flow between the high and low pressure sides of the shroud, said fluid deflecting member possessing a substantially fin-shaped fluid-deflecting surface which over at least the greater part of its area is oriented transversely of the direction of rotation of said blade, but not normal thereto, and faces towards both the high pressure side of the shroud and the trailing edge of the shroud, thereby to deflect at least a portion of said leakage flow and exchange momentum therewith, a force acting in the direction of blade rotation thereby being produced on said member to assist the rotation of said blade.
Claim 3
Dependent Claim
181 words
An axial flow turbine rotor blade having a shroud at its radially outer end and a fluid deflecting member projecting outwardly of the radially outer surface of said shroud into the region of leakage fluid flow between the high and low pressure sides of the shroud, said fluid deflecting member possessing a substantially fin-shaped fluid-deflecting surface which over at least the greater part of its area is oriented transversely of the direction of rotation of said blade, but not normal thereto, and faces towards both the high pressure side of the shroud and the trailing edge of the shroud, thereby to deflect at least a portion of said leakage flow and exchange momentum therewith, said rotor blade being adapted to be fluid-cooled, the cooling fluid being discharged from one or more apertures in the radially outer side of said shroud, at least a portion of said cooling fluid being deflected by the fin-shaped member to exchange momentum therewith, a force acting in the direction of blade rotation being thereby produced on said fin-shaped member to assist the rotation of said blade.
Claim 4
Dependent Claim
181 words
An axial flow turbine rotor blade having a shroud at its radially outer end and a fluid deflecting member projecting outwardly of the radially outer surface of said shroud into the region of leakage fluid flow between the high and low pressure sides of the shroud, said fluid deflecting member possessing a substantially fin-shaped fluid-deflecting surface which over at least the greater part of its area is oriented transversely of the direction of rotation of said blade, but not normal thereto, and faces towards both the high pressure side of the shroud and the trailing edge of the shroud, thereby to deflect at least a portion of said leakage flow and exchange momentum therewith, said rotor blade being adapted to be fluid-cooled, the cooling fluid being discharged from one or more apertures in the radially outer side of said shroud, at least a portion of said cooling fluid being deflected by the fin-shaped member to exchange momentum therewith, a force acting in the direction of blade rotation being thereby produced on said fin-shaped member to assist the rotation of said blade.
Claim 5
Dependent Claim
220 words
An axial flow turbine rotor blade having a shroud at its radially outer end and a fluid deflecting member projecting outwardly of the radially outer surface of said shroud into the region of leakage fluid flow between the high and low pressure sides of the shroud, said fluid deflecting member possessing a substantially fin-shaped fluid-deflecting surface which over at least the greater part of its area is oriented transversely of the direction of rotation of said blade, but not normal thereto, and faces towards both the high pressure side of the shroud and the trailing edge of the shroud, to thereby deflect at least a portion of said leakage flow and exchange momentum therewith, said rotor blade being fluid-cooled, the cooling fluid being discharged from apertures in the radially outer side of said shroud, at least one of said apertures being covered by a hollow cap member which is adapted to deflect said cooling fluid through one or more further apertures in said cap in a direction substantially opposite to the direction of rotation of said blade to assist therewith, the fin-shaped member being on the radially outer surface of said cap and projecting outwardly therefrom, said leakage fluid and said cooling fluid generating a force acting in the direction of blade rotation to assist the rotation of said blade.
Claim 6
Dependent Claim
220 words
An axial flow turbine rotor blade having a shroud at its radially outer end and a fluid deflecting member projecting outwardly of the radially outer surface of said shroud into the region of leakage fluid flow between the high and low pressure sides of the shroud, said fluid deflecting member possessing a substantially fin-shaped fluid-deflecting surface which over at least the greater part of its area is oriented transversely of the direction of rotation of said blade, but not normal thereto, and faces towards both the high pressure side of the shroud and the trailing edge of the shroud, to thereby deflect at least a portion of said leakage flow and exchange momentum therewith, said rotor blade being fluid-cooled, the cooling fluid being discharged from apertures in the radially outer side of said shroud, at least one of said apertures being covered by a hollow cap member which is adapted to deflect said cooling fluid through one or more further apertures in said cap in a direction substantially opposite to the direction of rotation of said blade to assist therewith, the fin-shaped member being on the radially outer surface of said cap and projecting outwardly therefrom, said leakage fluid and said cooling fluid generating a force acting in the direction of blade rotation to assist the rotation of said blade.
Claim 7
Dependent Claim
221 words
An axial flow turbine rotor blade having a shroud about its radially outer end and a fluid deflecting member projecting outwardly of the radially outer surface of said shroud into the region of leakage fluid flow between the high and low pressure sides of the shroud, said fluid deflecting member possessing a substantially fin-shaped fluid-deflecting surface which over at least the greater part of its area is oriented transversely of the direction of rotation of said blade, but not normal thereto, and faces towards both the high pressure side of the shroud and the trailing edge of the shroud, to thereby deflect at least a portion of said leakage flow and exchange momentum therewith, said turbine rotor blade being adapted to be fluid-cooled, the cooling fluid being discharged from apertures in the radially outer side of said shroud, at least one of said apertures being covered by a hollow cap member which is adapted to deflect said cooling fluid through at least one further aperture in said cap onto the fluid-flow deflecting surface of the fin-shaped member which projects outwardly from the radially outer surface of the shroud into the region of fluid-flow over said radially outer surface, a force being thereby produced which acts in the direction of blade rotation on said member to assist the rotation of said blade.
Claim 8
Dependent Claim
221 words
An axial flow turbine rotor blade having a shroud about its radially outer end and a fluid deflecting member projecting outwardly of the radially outer surface of said shroud into the region of leakage fluid flow between the high and low pressure sides of the shroud, said fluid deflecting member possessing a substantially fin-shaped fluid-deflecting surface which over at least the greater part of its area is oriented transversely of the direction of rotation of said blade, but not normal thereto, and faces towards both the high pressure side of the shroud and the trailing edge of the shroud, to thereby deflect at least a portion of said leakage flow and exchange momentum therewith, said turbine rotor blade being adapted to be fluid-cooled, the cooling fluid being discharged from apertures in the radially outer side of said shroud, at least one of said apertures being covered by a hollow cap member which is adapted to deflect said cooling fluid through at least one further aperture in said cap onto the fluid-flow deflecting surface of the fin-shaped member which projects outwardly from the radially outer surface of the shroud into the region of fluid-flow over said radially outer surface, a force being thereby produced which acts in the direction of blade rotation on said member to assist the rotation of said blade.
Claim 9
Dependent Claim
46 words
An axial flow turbine rotor blade according to claim 1 in which the fin-shaped member is of substantially triangular configuration and has its greatest height relative to the radially outer shroud surface at the position of greatest momentum of the flow of fluid over said surface.
Claim 10
Dependent Claim
32 words
An axial flow turbine rotor blade according to claim 1 in which the radially outer edge of said fin-shaped member is of substantially uniform height relative to the radially outer shroud surface.
Claim 11
Dependent Claim
29 words
An axial flow turbine rotor blade according to claim 1 in which the fluid-deflecting face of the fin-shaped member makes an acute angle with the radially outer shroud surface.
Claim 12
Dependent Claim
34 words
An axial flow turbine rotor blade according to claim 1 in which the radially outer free end of said fin-shaped member is of arcuate shape and overhangs the fluid-deflecting face of the fin-shaped member.
Claim 13
Dependent Claim
31 words
An axial flow turbine rotor blade according to claim 2 in which the fluid deflecting surface of the fin-shaped member is concave in the same sense as the blade aerofoil portion.
Claim 14
Dependent Claim
20 words
An axial flow turbine rotor blade according to claim 1, said blade being a gas turbine engine turbine rotor blade.
Claim 15
Dependent Claim
17 words
An axial flow turbine rotor blade according to claim 2 in which the cooling fluid is air.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |