Engine health monitoring

• US 9,830,747 B2
• Filed: 05/14/2008
• Issued: 11/28/2017
• Est. Priority Date: 06/12/2007
• Status: Active Grant

• Current Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Inventors: Apps, David, Smith, Timothy M.
• Primary Examiner(s): Tran, Khoi
• Assistant Examiner(s): ALSOMIRI, MAJDI A
• Application Number:
  US12/451,290
• Publication Number:
  US 20100138132A1
• Time in Patent Office: 3,485 Days
• Field of Search: 701 99-102, 701110, 701114, 60204, 60274, 60276, 60285, 60602, 60773, 60796
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: F02C 9/28 Regulating systems responsive to plant or ambient parameters, e.g. temperature, pressure, rotor speed F02C9/30 - F02C9/38, F02C9/44 take precedence
• CPC Class Codes: G07C 3/08 Registering or indicating the production of the machine either with or without registering working or idle time

Abstract

A method of monitoring the health of a gas turbine engine of at least a pair of engines of an aircraft for example. The method comprising the steps of: a) obtaining steady state readings from predetermined sensors on the engines; b) calculate a percentage difference of the steady state readings from a unique engine linear synthesis model for each engine; c) compare the difference between the percentage differences for each engine and d) where this difference exceeds a predetermined value issue a warning as to an engine health problem. Maintenance of the engine can therefore be advantageously scheduled.

Claims

1. A method of monitoring the health of a gas turbine engine of at least a pair of associated engines, the method comprising the steps of

obtaining in-flight steady state readings from predetermined sensors on the engines, comprising any one or more of a temperature, a pressure, and a spool speed,

calculating a percentage difference of the steady state readings from a unique engine linear synthesis model for each engine,

comparing the difference between the percentage differences for each engine and

where this difference exceeds a predetermined value issuing a warning as to an engine health problem, and

where the percentage differences of the steady state readings are calculated on a moving average basis normalized to zero.

2. A method as claimed in claim 1 wherein the predetermined value is +/−

0.5 or less than 0.5%.

3. A method as claimed in claim 2 wherein the predetermined value is between and includes 0.1% and 0.2%.

4. A method as claimed in claim 1 wherein the efficiency of a compressor

5. A method as claimed in claim 4 where T_in=Compressor Entry Temperature, T_out=Compressor Exit Temperature, P_in=Compressor Entry Pressure, P_out=Compressor Exit Pressure, and γ

=Ratio of Specific Heat (C_P/C_v).

6. A method as claimed in claim 1, wherein the moving average basis is conducted by redatuming each engine'"'"'s steady state readings.

7. A method as claimed in claim 6 wherein the redatuming is carried out between 3 and 6 months prior to engine deterioration.

8. A method as claimed in claim 1 wherein the unique engine linear synthesis model for each engine is an ideal steady state point for a perfect engine.

9. A method as claimed in claim 1 wherein the method comprises the step of analyzing other percentage differences and correlating to a known signature database.

10. A method as claimed in claim 1 wherein the method comprises the step of comparing the directions of change, increase or decrease, to a database of known engine problems or a matrix of component changes to provide a solution to the engine health problem.