Aerofoil body

Patent metadata

Field	Value
Publication number	US-10662803-B2
Application number	US-201715458154-A
Country	US
Kind code	B2
Filing date	Mar 14, 2017
Priority date	Apr 13, 2016
Publication date	May 26, 2020
Grant date	May 26, 2020

Abstract

An aerofoil body for a gas turbine engine is provided. The aerofoil body has leading and trailing edge portions, wherein one of the leading and trailing edge portions is a morphable edge portion having a composite layer structure. The aerofoil body further has a non-morphing central portion which forms pressure and suction surfaces of the aerofoil body between the leading and trailing edge portions. The composite layer structure includes a return spring, one or more shape memory alloy layers, and a flexible cover for the return spring and the one or more shape memory alloy layers. The flexible cover defines pressure and suction surfaces of the aerofoil body at the morphable edge portion. The one or more shape memory alloy layers are electrically heatable to deform the layers against the resistance of the return spring, and thereby alter the pitch of the aerofoil body at the morphable edge portion.

First claim

The invention claimed is:

1. An aerofoil body for a gas turbine engine, the aerofoil body having:
leading and trailing edge portions, wherein the leading edge portion is a morphable edge portion having a composite layer structure, and
a non-morphing central portion which forms pressure and suction surfaces of the aerofoil body between the leading and trailing edge portions;
wherein the composite layer structure includes a return spring, one or more shape memory alloy layers, and a flexible cover for the return spring and the one or more shape memory alloy layers, the flexible cover defining pressure and suction surfaces of the aerofoil body at the morphable edge portion, and the one or more shape memory alloy layers being electrically heatable to deform the layers against the resistance of the return spring and thereby alter the pitch of the aerofoil body at the morphable edge portion, and
wherein the return spring extends to a tip of the leading edge portion and the one or more shape memory alloy layers covers only a part of the return spring and stops before reaching the tip of the leading edge portion.

2. The aerofoil body according to claim 1 , wherein the composite layer structure is removably attached to the non-morphing central portion.

3. The aerofoil body according to claim 1 , wherein the return spring is a laminate return spring over which the one or more shape memory alloy layers extend.

4. The aerofoil body according to claim 3 , wherein the composite layer structure includes a first shape memory alloy layer on a pressure side of the spring and a second shape memory alloy layer on a suction side of the spring.

5. The aerofoil body according to claim 1 , wherein the composite layer structure further includes one or more electrical heating elements which respectively extend over the one or more shape memory alloy layers.

6. The aerofoil body according to claim 5 , having plural of the electrical heating elements radially distributed along the morphable edge portion, the radially distributed electrical heating elements being independently controllable to variably deform the one or more shape memory alloy layers against the resistance of the return spring and thereby alter the twist of the aerofoil body at the morphable edge portion.

7. The aerofoil body according to claim 1 , wherein the trailing edge portion is another morphable edge portion having a second composite layer structure.

8. The aerofoil body according to claim 1 , wherein the trailing edge portion is a non-morphable edge portion.

9. The aerofoil body according to claim 1 which is a guide vane of a gas turbine engine.

Assignees

• Rolls Royce Plc

Inventors

• Mears Matthew

Classifications

• F05D2300/603

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

• F05D2270/62

  Electrical actuators · CPC title

• F01D17/162 Primary

  for axial flow, i.e. the vanes turning around axes which are essentially perpendicular to the rotor centre line (F01D17/167 takes precedence) · CPC title

• F01D9/041

  using blades (F01D5/148 takes precedence) · CPC title

• F05D2240/121

  related to the leading edge of a stator vane · CPC title