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US4940388A Expired / Lapsed US ⏱️ 0.0 years remaining

Cooling of turbine blades

Assignee: Rolls Royce PLC
•
Filing: 1989-11-17
•
Granted: 1990-07-10
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Expires: 2009-11-17
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Abstract

Abstract In order to facilitate efficient use of high pressure cooling air in a turbine rotor blade its aerofoil has a triple-pass convoluted cooling air duct in its leading edge region, and a triple-pass convoluted cooling air duct in its mid-chord region, both of them being fed from a common high pressure inlet in the root of the blade. The trailing edge region has a single-pass duct fed by low pressure cooling air from an inlet located just under the blade platform. The shroud of the blade also has cooling air passages and these are fed from the ends of respective ones of the ducts. Air from the ducts also exits through rows of film cooling holes to film cool the concave flank of the aerofoil and through a row of holes in its trailing edge to remove heat from the thinner metal section in that area.

Inventors

  • 👤 Jonathan R. Lilleker
  • 👤 Harry Henshaw
  • 👤 John L. Winter

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 22:17
CPC Classifications
F; F01; F01D; F01D5/00; F01D5/12; F01D5/14; F01D5/18; F01D5/187; F01D5/22; F01D5/225; F05; F05D; F05D2240/00; F05D2240/80; F05D2240/81; F05D2260/00; F05D2260/20; F05D2260/221; F05D2260/2214

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 148 words
An air cooled turbine blade for an axial flow gas turbine aeroengine has a root portion, an inner platform and an aerofoil, the aerofoil having a chordwise succession of substantially mutually parallel cooling air passages extending spanwise of the aerofoil, first and second pluralities of the passages being connected in flow series at their extremities to form respective separate first and second convoluted pathways in the leading edge and mid-chord regions of the aerofoil respectively, both said convoluted pathways being connected to a first cooling air entry port located below the inner platform, the trailing edge portion of the aerofoil having at least one spanwise extending cooling air passage therein connected to a second cooling air entry port located below the inner platform, in use the first entry port receiving cooling air at a high pressure and the second entry port receiving cooling air at a lower pressure.
Claim 2
Dependent Claim 148 words
An air cooled turbine blade for an axial flow gas turbine aeroengine has a root portion, an inner platform and an aerofoil, the aerofoil having a chordwise succession of substantially mutually parallel cooling air passages extending spanwise of the aerofoil, first and second pluralities of the passages being connected in flow series at their extremities to form respective separate first and second convoluted pathways in the leading edge and mid-chord regions of the aerofoil respectively, both said convoluted pathways being connected to a first cooling air entry port located below the inner platform, the trailing edge portion of the aerofoil having at least one spanwise extending cooling air passage therein connected to a second cooling air entry port located below the inner platform, in use the first entry port receiving cooling air at a high pressure and the second entry port receiving cooling air at a lower pressure.
Claim 3
Dependent Claim 40 words
An air cooled turbine blade according to claim 1 in which the first cooling air entry port is preferably connected to that cooling air passage which is nearest the leading edge of the aerofoil in each of the convoluted paths.
Claim 4
Dependent Claim 56 words
An air cooled turbine blade according to claim 1 additionally having an integral shroud portion with at least one shroud cooling air passage disposed therein to convey cooling air laterally across the shroud, the shroud cooling air passage being connected to one of the convoluted pathways in the aerofoil to receive high pressure cooling air therefrom.
Claim 5
Dependent Claim 25 words
An air cooled turbine blade according to claim 3 in which the shroud cooling air passage is connected to the end of the convoluted pathway.
Claim 6
Dependent Claim 20 words
An air cooled turbine blade according to claim 1 in which the first convoluted pathway comprises three cooling air passages.
Claim 7
Dependent Claim 20 words
An air cooled turbine blade according to claim 1 in which the second convoluted pathway comprises three cooling air passages.
Claim 8
Dependent Claim 51 words
An air cooled turbine blade according to claim 1 in which the first entry port is at the base of the root portion of the blade and the second entry port is at the top of the root portion of the blade, in or near the underside of the inner platform.

References Cited (Backward Citations)

US3533711A Cited
US4073599A Cited
US4136516A Cited
GB1600109A Cited
JPS5713201A Cited
US4462754A Cited
JPS58202304A Cited
JPS60135605A Cited
EP0241180A2 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-07-09 1994-01-08 1994-07-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-07-09 1998-01-08 1998-07-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-07-09 2002-01-08 2002-07-10 $7700.00 Window Closed / Lapsed

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