Gas turbine engine operating schedules for optimizing ceramic matrix composite component life

Patent metadata

Field	Value
Publication number	US-11536205-B2
Application number	US-202016835942-A
Country	US
Kind code	B2
Filing date	Mar 31, 2020
Priority date	Mar 31, 2020
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

A gas turbine engine system includes an engine component comprising ceramic matrix composite materials, at least one control system configured to control at least a temperature of the engine component, and a controller. The controller includes a degradation map stored therein. The degradation map includes degradation fields, each field defined by a unique range of temperatures and stresses of the component and correlated to different types of degradation of the component. The controller is configured to determine a first temperature and stress of the component and a first field based on the first temperature and stress, determine a second field different from the first and a second temperature and stress that would locate the component in the second field, and instruct the control system to change the temperature of the component from the first to the second temperature to locate the component in the second field.

First claim

What is claimed is:

1. A gas turbine engine system comprising
an engine core including a first engine component comprising ceramic matrix composite materials,
at least one control system configured to control a temperature of the first engine component to effect a stress applied to the first engine component, and
a controller including a degradation mechanism map stored therein, the degradation mechanism map comprising a plot of stress of the first engine component versus temperature of the first engine component, the degradation mechanism map including a plurality of degradation fields, each of the plurality of degradation fields defined by a unique range of temperatures of the first engine component and a unique range of stresses applied to the first engine component, each of the plurality of degradation fields correlating to different degradation types of the first engine component, and the controller configured to
determine the first engine component is operating at a first predetermined temperature,
determine a first degradation field of the plurality of degradation fields of the first engine component that is located on the degradation mechanism map based on the first predetermined temperature and a first stress of the first engine component caused by the first engine component operating at the first predetermined temperature,
determine a second degradation field of the plurality of degradation fields that is different than the first degradation field, the second degradation field being located based on a second predetermined temperature and a second stress of the first engine component caused by the first engine component operating at the second predetermined temperature that would locate the first engine component in the second degradation field, and
generate instructions to cause the at least one control system to change the temperature of the first engine component from the first predetermined temperature to the second predetermined temperature to cause the second stress to be applied to the first engine component such that the first engine component is located in the second degradation field such that the first engine component is not located in the first degradation field for longer than a predetermined duration.

2. The gas turbine engine system of claim 1 , wherein the first predetermined temperature includes a predicted temperature of the first engine component and the first stress is a predicted stress of the first engine component.

3. The gas turbine engine system of claim 1 , wherein the first and second predetermined temperatures are based on predetermined properties of the first engine component, and wherein the controller is further configured to generate the degradation mechanism map via directly measured properties of the first engine component for at least the first operating condition.

4. The gas turbine engine system of claim 1 , wherein
the controller is further configured to
determine whether the first engine component being located in first degradation field will cause a first degradation level of the first engine component that exceeds a threshold degradation level of the first engine component, and
in response to a determination that the first degradation level will exceed the threshold degradation level, determine the second degradation field, and

the first engine component being located in the second degradation field causes a second degradation level of the first engine component that does not exceed the threshold degradation level of the first engine component.

5. The gas turbine engine system of claim 4 , wherein
the first degradation level indicates at least some degradation of the first engine component, and
the second degradation level indicates no degradation of the first engine component.

6. The gas turbine engine system of claim 4 , wherein
the first degradation level indicates at least some degradation of the first engine component,
the second degradation level indicates at least some degradation of the first engine component, and
the first degradation level is greater than the second degradation level.

7. The gas turbine engine system of claim 1 , wherein
the gas turbine engine system is configured for use in at least one gas turbine engine of an aircraft, and
the at least one control system includes at least one of
a turbine cooling flow system of the at least one gas turbine engine,
at least one fuel metering valve of the at least one gas turbine engine,
at least one variable stator vane of the at least one gas turbine engine,
at least one environmental control system of the aircraft, and
an autopilot system of the aircraft.

8. The gas turbine engine system of claim 1 , further comprising
a second component,
wherein the controller is further configured to
determine a third temperature of the second engine component and a third stress applied to the second engine component for the first operating condition of the engine core,
determine a third degradation field of the plurality of degradation fields of the second engine component that is located based on the third temperature and the third stress,
determine a fourth degradation field of the plurality of degradation fields that is different than the third degradation field,
determine a fourth temperature of the second engine component to cause a fourth stress to be applied to the second engine component that would locate the second engine component in the fourth degradation field, and
generate instructions to cause the at least one control system to change the third temperature of the second engine component to the fourth temperature to cause the fourth stress to be applied to the second engine component such that the second engine component is located in the fourth degradation field such that the second engine component is not located in the third degradation field for longer than a second predetermined duration.

9. The gas turbine engine system of claim 8 , wherein
the third degradation field is the same as the first degradation field and the fourth degradation field is the same as the second degradation field, or
the third degradation field is the same as the first degradation field and the fourth degradation field is different than the second degradation field, or
the third degradation field is different than the first degradation field and the fourth degradation field is the same as the second degradation field, or
the third degradation field is different than the first degradation field and the fourth degradation field is different than the second degradation field.

10. The gas turbine engine system of claim 8 , wherein the third degradation field is different than the first degradation field and the fourth degradation field is different than the second degradation field.

11. The gas turbine engine system of claim 1 , wherein the second temperature is greater than the first temperature and the second stress is greater than the first stress.

12. The gas turbine engine system of claim 1 , wherein the control system is further configured generate instructions to change the first temperature of the first engine component to the second temperature to cause the second stress to be applied to the first engine component while keeping the first temperature and the second temperature outside of a range of 900° F. to 1700° F.

13. A gas turbine engine system comprising
a controller including a degradation mechanism map for a first engine component of an engine core of the gas turbine engine system stored therein, the degradation mechanism map comprising a plot of stress of the first engine component versus temperature of the

Assignees

• Rolls Royce Plc

Inventors

• Whittle Michael J
• Edmonds Ian M
• Harris Stephen

Classifications

• F05D2260/941

  particularly aimed at mechanical or thermal stress reduction · CPC title

• F05D2270/3032

  excessive temperatures, e.g. caused by overheating · CPC title

• F05D2270/114

  by limiting mechanical stresses · CPC title

• F01D21/12

  responsive to temperature · CPC title

• F05D2270/44

  active, predictive, or anticipative · CPC title