Blade tip

Patent metadata

Field	Value
Publication number	US-9850764-B2
Application number	US-201514613744-A
Country	US
Kind code	B2
Filing date	Feb 4, 2015
Priority date	Feb 28, 2014
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

There is provided a blade tip for a rotary blade. The blade tip is formed of a metal foam and comprises at least one vortex generator. The vortex generator may comprise at least one passageway and/or cavity in the blade tip. In use, a vortex is created between the blade tip and a fan casing adjacent the blade tip.

First claim

We claim:

1. A blade tip for a rotary blade, wherein the blade tip is formed of a metal foam and comprises at least one vortex generator comprising at least one passageway, such that, in use, a vortex is created between the blade tip and a casing adjacent the blade tip, wherein the vortex generator comprises a passageway extending from an inlet on a pressure face of the blade tip to at least one outlet on a radially outer surface of the blade tip, and the outlet(s) of the passageway are substantially mid-way between the pressure and suction surfaces on the camber line of the rotary blade.

2. A blade tip according to claim 1 wherein the vortex generator comprises at least one cavity in the blade tip.

3. A blade tip according to claim 1 wherein the passageway is a curved or spiral passageway.

4. A blade tip according to claim 1 wherein the passageway is funnelled with the inlet having a greater cross-sectional area than the/each outlet.

5. A blade tip according to claim 1 wherein the blade tip has a plurality of passageways.

6. A blade tip according to claim 1 wherein the vortex generator comprises a chisel tip section having a chisel or wedge-shaped protrusion extending from a pressure surface of the blade tip.

7. A blade tip according to claim 1 wherein the vortex generator comprises a squealer tip section comprising a wall extending radially outwards around the perimeter of a radially outer surface of the blade tip and defining a central tip cavity.

8. A blade tip according to claim 1 wherein the metal foam blade tip comprises reinforcing fibres.

9. A blade tip according to claim 1 wherein an insulating material is infused into the metal foam.

10. A rotary blade having a blade tip according to claim 1 , the rotary blade having a blade body comprising a composite material.

11. A fan comprising a plurality of rotary blades according to claim 10 .

12. A gas turbine engine comprising a fan according to claim 11 .

13. A method of making a blade tip according to claim 1 , said method comprising forming the metal foam around a shaping element, the shaping element being dimensioned and positioned to correspond to desired shape and position of the passageway in the blade tip, and, subsequently removing the shaping element from the blade tip.

14. A method according to claim 13 further comprising:
a) constructing a precursor comprising a plurality of beads secured to a fibre;
b) arranging a plurality of the precursors in a processing vessel around the shaping element, the shaping element being dimensioned and positioned to correspond to desired shape and position of the passageway in the blade tip; and
c) depositing metal on the surfaces of the beads to form the blade tip.

15. A method according to claim 13 wherein the shaping element is removed by physically extracting the shaping element in an intact form, or by leaching or melting the shaping element.

16. A method according to claim 14 wherein the method further comprises exposing the fibre of at least some of the precursors during deposition of the metal.

17. A method according to claim 13 wherein the method further comprises infusing an insulating material into the blade tip.

18. A method of making a rotary blade comprising forming a blade tip according to claim 1 and integrating the blade tip into a blade body of the rotary blade, the blade body being a composite material.

Assignees

• Rolls Royce Plc

Inventors

• Care Ian Colin Deuchar
• Baralon Stephane

Classifications

• F05D2300/603

  Composites; e.g. fibre-reinforced · CPC title

• F01D5/147

  Construction, i.e. structural features, e.g. of weight-saving hollow blades (F01D5/148, F01D5/16 and F01D5/20 take precedence; blade shape F01D5/141; blades with cooling or heating channels or cavities F01D5/18; heating, heat-insulating or cooling means on blades F01D5/18) · CPC title

• F04D29/023

  especially adapted for elastic fluid pumps · CPC title

• F05D2300/6032

  Metal matrix composites [MMC] · CPC title

• F05D2210/33

  Turbulent flow · CPC title