Thermal engine encapsulation diagnostic

Patent metadata

Field	Value
Publication number	US-10450981-B2
Application number	US-201715614761-A
Country	US
Kind code	B2
Filing date	Jun 6, 2017
Priority date	Jun 6, 2017
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

Methods and systems are provided for diagnosing an engine thermal encapsulation positioned around a powertrain of a vehicle. In one example, degradation of the thermal encapsulation may be determined by comparing a temperature sampled via a sensor during engine off condition with an expected temperature.

First claim

The invention claimed is:

1. A method comprising:
sampling a temperature, via a sensor positioned onboard a vehicle driven by a powertrain having an engine, during an engine off condition; and
indicating, via a controller, degradation of a thermal encapsulation positioned at least partially around the powertrain responsive to a temperature difference between the sampled temperature and an expected temperature.

2. The method of claim 1 , further comprising fitting, via the controller, the sampled temperature with a curve based on thermal conduction and thermal convection.

3. The method of claim 2 , further comprising calculating, via the controller, the temperature difference by comparing coefficients of the curve with coefficients of a profile of the expected temperature, wherein the expected temperature profile is determined by fitting the expected temperature.

4. The method of claim 1 , further comprising fitting, via the controller, the sampled temperature based on vehicle conditions including one or more of status of a hood, status of a grille shutter, vehicle speed, humidity of the thermal encapsulation material, status of a cooling fan, status of a block heater, operating conditions of the engine, and weather.

5. The method of claim 4 , wherein the humidity of the thermal encapsulation material is estimated based on weather.

6. The method of claim 1 , further comprising fitting, via the controller, the sampled temperature based on sensor location.

7. The method of claim 1 , wherein the temperature difference between the sampled temperature and the expected temperature is a first temperature difference, the method further comprising sampling a second temperature via a second sensor, and indicating, via the controller, degradation of the thermal encapsulation further in response to a second temperature difference between the second temperature and a second expected temperature.

8. The method of claim 7 , further comprising indicating, via the controller, degradation of the thermal encapsulation based on a weighted average of the first temperature difference and the second temperature difference, wherein the first and second temperature differences are weighted based on sensor location.

9. The method of claim 1 , further comprising generating, via the controller, the expected temperature from a second powertrain with a second thermal encapsulation position at least partially around the second powertrain, the second powertrain is a prototype powertrain or a model of the powertrain.

10. The method of claim 1 , further comprising generating, via the controller, the expected temperature from a second powertrain without thermal encapsulation, the second powertrain is a prototype powertrain or a model of the powertrain.

11. A method comprising:
during engine operation, diagnosing, via a controller, a vehicle for degradation based on a first temperature profile generated via a first sensor;
in response to shutdown of an engine which propels the vehicle, indicating, via the controller, degradation of a thermal encapsulation positioned at least partially around a powertrain, which includes the engine, responsive to a temperature difference between a second temperature profile generated via a second sensor and an expected temperature profile; and
operating the vehicle in response to the temperature difference.

12. The method of claim 11 , further comprising during engine operation, operating the vehicle in response to the vehicle diagnosis.

13. The method of claim 12 , further comprising diagnosing, via the controller, vehicle components other than the thermal encapsulation during engine warm up.

14. The method of claim 11 , wherein the first sensor and the second sensor are the same sensor.

15. The method of claim 11 , further comprising indicating, via the controller, degradation of the thermal encapsulation responsive to a temperature difference between the first temperature profile and a second expected temperature profile.

16. A vehicle system, comprising:
a thermal encapsulation at least partially enclosing a powertrain having an engine;
a sensor; and
a controller configured with computer readable instructions stored on a non-transitory memory for:
during engine start, generating a first temperature profile via the sensor at a first frequency, and calculating a first temperature difference between the first generated temperature profile and a first expected temperature profile;
during engine shutdown, generating a second temperature profile via the sensor at a second frequency, and calculating a second temperature difference between the second temperature profile and a second expected temperature profile; and
indicating degradation of the thermal encapsulation based on both the first temperature difference and the second temperature difference.

17. The system of claim 16 , wherein the controller is further configured for indicating the thermal encapsulation degradation based on a weighted average of the first temperature difference and the second temperature difference, and weighting factors for the first and second temperature differences are different.

18. The system of claim 16 , wherein the first frequency is higher than the second frequency.

19. The system of claim 16 , wherein the controller is further configured for diagnosing vehicle components other than the thermal encapsulation based on the first temperature profile, and indicating degradation of the thermal encapsulation responsive to no degradation in vehicle components other than the thermal encapsulation.

20. The system of claim 16 , wherein the controller is further configured for adjusting vehicle operating parameters in response to indicated thermal encapsulation degradation.

Assignees

• Ford Global Tech Llc

Inventors

• Tascillo Mark Anthony
• Leone Thomas G
• Miller Kenneth James
• Ruona William Charles

Classifications

• B60H1/00499

  Heat or cold storage without phase change including solid bodies, e.g. batteries · CPC title

• F02D2250/14

  Timing of measurement, e.g. synchronisation of measurements to the engine cycle · CPC title

• F02D2200/021

  Engine temperature · CPC title

• F02D41/22

  Safety or indicating devices for abnormal conditions {(in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809)} · CPC title

• F02B77/083

  relating to maintenance, e.g. diagnostic device (relating to lubrication F01M11/10) · CPC title