Systems and methods for diagnosing an engine

• US 9,151,695 B2
• Filed: 06/19/2012
• Issued: 10/06/2015
• Est. Priority Date: 06/19/2012
• Status: Active Grant

• Current Assignee: GE Global Sourcing LLC (Westinghouse Air Brake Technologies Corporation)
• Original Assignee: General Electric Company
• Inventors: Worden, Bret Dwayne, Strode, Jason M., Karunaratne, Milan
• Primary Examiner(s): Kirkland, III, Freddie
• Application Number:
  US13/526,787
• Publication Number:
  US 20130338899A1
• Time in Patent Office: 1,204 Days
• Field of Search: 73/40
• US Class Current: 1/1
• CPC Class Codes: F01P 11/18 concerning coolant pressure, coolant flow, or liquid-coolant level
• CPC Class Codes: F01P 2031/18 Detecting fluid leaks
• CPC Class Codes: F02D 28/00 Programme-control of engines
• CPC Class Codes: G01M 15/09 by monitoring pressure in fluid ducts, e.g. in lubrication or cooling parts
• CPC Class Codes: G01M 3/025 Details with respect to the testing of engines or engine parts
• CPC Class Codes: G01M 3/3227 for radiators

Abstract

Presently disclosed are methods and systems for detecting and diagnosing a coolant leak of an engine. A method may include diagnosing a coolant leak of the engine based on a low frequency pressure response of a measured engine coolant pressure. A vehicle system is also disclosed, including an engine, a coolant system operatively connected to the engine. The coolant system includes a coolant reserve and a coolant pump between the engine and the coolant reserve. The vehicle also includes a coolant pressure sensor to measure coolant pressure, and a controller configured to measure an engine coolant pressure and diagnose a coolant leak of the coolant system based on a low frequency pressure response of the measured engine coolant pressure.

Claims

1. A method for an engine comprising:

analyzing a measured engine coolant pressure in a frequency range of no more than 5 Hz to determine a low frequency pressure response, and

diagnosing a coolant leak of the engine based on the low frequency pressure response of the measured engine coolant pressure.

2. The method of claim 1, wherein the low frequency pressure response corresponds to a loss of prime stability of a coolant pump of the engine.

3. The method of claim 2, wherein the low frequency pressure response has a frequency no greater than 1% of a blade frequency of the coolant pump.

4. The method of claim 1, wherein the coolant leak is diagnosed based on the low frequency pressure response comprising at least a designated number of pressure deviations greater than a designated threshold within a designated time interval.

5. The method of claim 4 further comprising:

identifying each of the pressure deviations as comprising an increase in the measured engine coolant pressure and a decrease in the measured engine coolant pressure.

6. The method of claim 4, wherein the designated threshold is a rate of change of the monitored engine coolant pressure of at least 68900 Pascal per second.

7. The method of claim 6, wherein the designated number of pressure deviations is three and the designated time interval is one minute.

8. The method of claim 1 further comprising:

determining the low frequency pressure response of the measured engine coolant pressure by determining a rate of change of the measured engine coolant pressure over time.

9. The method of claim 8 further comprising:

comparing the determined rate of change of the measured engine coolant pressure with a designated threshold to identify a pressure deviation, wherein the coolant leak is diagnosed at least in part based on the pressure deviation that is identified.

10. The method of claim 8 further comprising:

identifying a pressure deviation as a change in the polarity of the determined rate of change of the measured engine coolant pressure, wherein the coolant leak is diagnosed at least in part based on the pressure deviation that is identified.

11. The method of claim 1 further comprising:

determining the low frequency pressure response of the measured engine coolant pressure from a frequency analysis of the measured engine coolant pressure over a selected time interval.

12. The method of claim 1 further comprising:

pumping coolant from a coolant source to a coolant draw in a closed-volume coolant circuit, detecting a pump operating speed, and measuring the engine coolant pressure at the pump operating speed.

13. The method of claim 1 further comprising:

measuring the engine coolant pressure at an outlet to a pump disposed in a coolant circuit of the engine.

14. The method of claim 1 further comprising:

sampling the measured engine coolant pressure at a specified operating speed of a coolant pump of the engine.

15. The method of claim 1 further comprising:

continuously monitoring the measured engine coolant pressure during transitions between at least two operating speeds of a coolant pump of the engine.

16. The method of claim 1 further comprising:

generating a signal in response to diagnosing the coolant leak based on the low frequency pressure response of the measured engine coolant pressure, wherein the signal corresponds to a severity level of the coolant leak.

17. The method of claim 1 further comprising:

notifying personnel via one or more of an audio alarm, a visual alarm, a text message, an e-mail, an instant message, a phone call, or an electronic signal in response to diagnosing the coolant leak based on the low frequency pressure response of the measured engine coolant pressure.

18. A method comprising:

receiving a signal from a coolant pressure sensor corresponding to a sensed engine coolant pressure of engine coolant of an engine system of a vehicle;

based at least in part on the signal, determining a low frequency pressure response of the sensed engine coolant pressure by analyzing the sensed engine coolant pressure in a frequency range of no more than 5 Hz;

determining whether the low frequency pressure response meets one or more criteria indicative of a coolant leak of the engine system;

and if the low frequency pressure response meets the one or more criteria, communicating a signal indicative of the coolant leak for at least one of controlling the vehicle or alerting an entity of the coolant leak.

19. A vehicle system comprising:

an engine;

a coolant system operatively connected to the engine, the coolant system having a coolant reserve and a coolant pump, wherein the coolant pump is disposed between the coolant reserve and the engine;

a coolant pressure sensor configured to measure engine coolant pressure; and

a controller configured to;

receive a signal from the coolant pressure sensor corresponding to the measured engine coolant pressure;

analyze the signal corresponding to the measured engine coolant pressure in a frequency range of no more than 5 Hz to determine a low frequency pressure response; and

diagnose a coolant leak of the vehicle system based on the low frequency pressure response of the measured engine coolant pressure.

20. The vehicle system of claim 19, wherein the low frequency pressure response is an indication of a loss of prime stability of a coolant pump.

21. The vehicle system of claim 19, wherein the low frequency pressure response comprises at least a designated number of pressure deviations greater than a designated threshold within a designated time interval.

22. The vehicle system of claim 21, wherein each of the pressure deviations comprises an increase in the measured engine coolant pressure and a decrease in the measured engine coolant pressure.

23. The vehicle system of claim 21, wherein the designated threshold is a rate of change of the monitored pressure of at least 68900 Pascal per second.

24. The vehicle system of claim 21, wherein the designated number of pressure deviations is three and the designated time interval is one minute.

25. A controller configured to:

receive a signal corresponding to a measured engine coolant pressure;

determine a low frequency pressure response of the measured engine coolant pressure by analyzing the sensed engine coolant pressure in a frequency range of no more than 5 Hz; and

diagnose a coolant leak based on the low frequency pressure response of the measured engine coolant pressure.