Embedded sensor for in-situ monitoring of blade tip incursion

Patent metadata

Field	Value
Publication number	US-9939247-B1
Application number	US-201615368963-A
Country	US
Kind code	B1
Filing date	Dec 5, 2016
Priority date	Dec 5, 2016
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

A wear monitoring system for measuring incursion depth into an abradable coating includes a layer of abradable coating including a depth. At least one measurement circuit includes a plurality of conductive leads disposed within the abradable coating. The conductive leads are spaced radially apart within a common radial plane corresponding to the depth of the abradable coating. A plurality of resistor elements corresponds with the plurality of conductive leads. Each of the plurality of resistor elements are in electrical communication with one of the plurality of conductive leads disposed within the common radial plane of the corresponding one of the plurality of conductive leads. An electrical characteristic of the circuit varies responsive to cutting of one or more of the plurality of conductive leads by a passing airfoil. A gas turbine engine and method are also disclosed.

First claim

What is claimed is:

1. A wear monitoring system for measuring incursion depth into an abradable coating comprising:
a layer of abradable coating including a depth;
at least one measurement circuit including a plurality of conductive leads disposed within the abradable coating, the conductive leads spaced radially apart within a common radial plane corresponding to the depth of the abradable coating; and
a plurality of resistor elements corresponding with the plurality of conductive leads, each of the plurality of resistor elements in electrical communication with one of the plurality of conductive leads disposed within the common radial plane of the corresponding one of the plurality of conductive leads; wherein an electrical characteristic of the circuit varies responsive to cutting of one or more of the plurality of conductive leads by a passing airfoil.

2. The wear monitoring system as recited in claim 1 , wherein each of the plurality of resistor elements are arranged in parallel.

3. The wear monitoring system as recited in claim 2 , wherein at least two of the plurality of resistor elements provide a different resistance.

4. The wear monitoring system as recited in claim 2 , including at least two probes in electrical communication with the plurality of conductive leads and the corresponding plurality of resistor elements.

5. The wear monitoring system as recited in claim 1 , wherein each of the resistor elements comprises a resistor element material dispersed between end leads corresponding with the corresponding one of the plurality of conductive leads.

6. The wear monitoring system as recited in claim 5 , wherein a volume of the resistor element material between the end leads is varied to define a resistance value for each of the plurality of resistor elements.

7. The wear monitoring system as recited in claim 6 , wherein the resistor element material between the end leads defines a uniform cross-section and a portion of resistor element materials with a non-uniform cross-section extends past each of the end leads.

8. The wear monitoring system as recited in claim 1 , wherein the measurement circuit is formed on an insulating layer and an encapsulating layer is applied over the measurement circuit, wherein each of the insulating layer, measurement circuit and encapsulating layers are disposed within separate and parallel radially extending planes.

9. The wear monitoring system as recited in claim 1 , including a controller in communication with the measurement circuit that receives information indicative of an incursion of an airfoil into the radial depth of the abradable material.

10. A gas turbine engine comprising:
a fan including a plurality of fan blades rotatable about an axis;
a compressor section;
a combustor in fluid communication with the compressor section;
a turbine section in fluid communication with the combustor, wherein at least one of the compressor section and the turbine section includes an airfoil having a tip;
an abradable coating that wears away responsive to incursion of the tip to define a desired clearance; and
a wear sensor system comprising at least one measurement circuit including a plurality of conductive leads disposed within the abradable coating, the conductive leads spaced radially apart within a common radial plane corresponding to the depth of the abradable coating, and a plurality of resistor elements corresponding with the plurality of conductive leads, each of the plurality of resistor elements in electrical communication with one of the plurality of conductive leads and disposed within the common radial plane of the corresponding one of the plurality of conductive leads, wherein an electrical characteristic of the at least one measurement circuit varies responsive to cutting of one or more of the plurality of conductive leads by the tip.

11. The gas turbine engine as recited in claim 10 , wherein each of the plurality of resistor elements are arranged in parallel.

12. The gas turbine engine as recited in claim 10 , wherein at least two of the plurality of resistor elements provide a different resistance.

13. The gas turbine engine as recited in claim 10 , including at least two probes in electrical communication with the plurality of conductive leads and the corresponding plurality of resistor elements.

14. The gas turbine engine as recited in claim 10 , wherein each of the resistor elements comprises a resistor element material dispersed between end leads corresponding with the corresponding one of the plurality of conductive leads.

15. The gas turbine engine as recited in claim 14 , wherein a volume of the resistor element material between the end leads is varied to define a resistance value for each of the plurality of resistor elements.

16. The gas turbine engine as recited in claim 15 , wherein the resistor element material between the end leads defines a uniform cross-section and a portion of resistor element materials with a non-uniform cross-section extends past each of the end leads.

17. The gas turbine engine as recited in claim 10 , wherein the measurement circuit is formed on an insulating layer applied over the abradable material and an encapsulating layer is applied over the measurement circuit, wherein each of the insulating layer, measurement circuit and encapsulating layers are disposed within separate and parallel radially extending planes.

18. The gas turbine engine as recited in claim 10 , including a controller in communication with the measurement circuit that receives information indicative of an incursion of an airfoil into the radial depth of the abradable material.

19. A method of assembling a wear sensor system for monitoring wear of an abradable coating comprising:
applying a layer of abradable coating to a desired radial depth proximate an airfoil;
forming a plurality of conductive leads disposed within the abradable coating, the conductive leads spaced radially apart within a common radial plane corresponding to the radial depth of the abradable coating;
assembling a plurality of resistor elements corresponding with the plurality of conductive leads, each of the plurality of resistor elements in electrical communication with one of the plurality of conductive leads and disposed radially outward within the common radial plane of the corresponding one of the plurality of conductive leads; and
providing probes in electrical communication with the plurality of conductive leads and the plurality of resistor elements such that an electrical characteristic varies responsive to cutting of one or more of the plurality of conductive leads by an airfoil and that the electrical characteristic is indicative of a depth at which the airfoil has penetrated the radial depth of the abradable coating.

20. The method as recited in claim 19 , comprising applying of an insulating coating onto the abradable coating along a radial plane and forming the plurality of conductive leads and the plurality of resistor elements onto the insulating coating.

21. The method as recited in claim 20 , including applying an encapsulating coating over the plurality of conductive leads and the plurality of resistor elements.

22. The method as recited in claim 21 including defining each of the resistor elements with a resistor element material dispersed between end leads corresponding with the corresponding one of the plurality of conductive leads.

23. The method as recited in claim 22 , wherein a volume of the resisto

Assignees

• United Technologies Corp

Inventors

• Dardona Sameh
• Sheedy Paul
• Piech Marcin
• Grande Daniel Anthony
• Schmidt Wayde R
• Tokgoz Cagatay
• Kasprow Thomas D
• Protsailo Lesia V

Classifications

• G01B7/26 Primary

  for measuring depth · CPC title

• G01M15/14

  Testing gas-turbine engines or jet-propulsion engines · CPC title

• G01B7/06

  for measuring thickness {(measuring during the manufacture of coatings C23C14/54)} · CPC title