Systems and method for controlling auto-ignition

Patent metadata

Field	Value
Publication number	US-9920683-B2
Application number	US-201414190482-A
Country	US
Kind code	B2
Filing date	Feb 26, 2014
Priority date	Feb 26, 2014
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

Various methods and systems are provided for maintaining combustion stability in a multi-fuel engine. In one example, a system comprises a first fuel system to deliver liquid fuel to at least one cylinder of an engine, a second fuel system to deliver gaseous fuel to the at least one cylinder, and a controller. The controller is configured to supply the gaseous fuel to the at least one cylinder, inject the liquid fuel to the at least one cylinder thereby to ignite the liquid fuel and the gaseous fuel in the at least one cylinder via compression-ignition, and adjust an amount of the gaseous fuel relative to an amount of the liquid fuel based on a measured parameter associated with auto-ignition of end gases subsequent to the compression-ignition of the liquid fuel.

First claim

The invention claimed is:

1. A system, comprising:
a first fuel system to deliver liquid fuel to at least one cylinder of an engine;
a second fuel system to deliver gaseous fuel to the at least one cylinder; and
a controller storing non-transitory instructions executable to:
supply the gaseous fuel to the at least one cylinder;
inject the liquid fuel to the at least one cylinder thereby to ignite the liquid fuel and the gaseous fuel in the at least one cylinder via compression-ignition;
adjust an amount of the gaseous fuel relative to an amount of the liquid fuel based on a measured parameter associated with auto-ignition of end gases subsequent to the compression-ignition of the liquid fuel; and
retard an injection timing of the injection of the liquid fuel in response to the measured parameter.

2. The system of claim 1 , wherein the measured parameter comprises vibration of the engine.

3. The system of claim 1 , wherein the instructions are executable to decrease the amount of gaseous fuel relative to the amount of liquid fuel in response to the measured parameter.

4. The system of claim 3 , wherein the instructions are executable to, after decreasing the amount of gaseous fuel relative to the amount of liquid fuel and responsive to the measured parameter indicating that the auto-ignition of end gases has ceased, increase the amount of gaseous fuel relative to the amount of liquid fuel.

5. The system of claim 3 , wherein the instructions are executable to, after decreasing the amount of gaseous fuel relative to the amount of liquid fuel and responsive to the measured parameter indicating that the auto-ignition of end gases has not ceased, deactivate the supply of gaseous fuel to the at least one cylinder and increase the amount of liquid fuel to maintain engine power.

6. The system of claim 1 , wherein the injection of liquid fuel comprises a stratified injection of liquid fuel.

7. The system of claim 1 , wherein the at least one cylinder comprises a first cylinder including a first gas admission valve and a first liquid fuel injector, and a second cylinder including a second gas admission valve and a second liquid fuel injector, and wherein the instructions are executable to identify, based on the measured parameter, if the auto-ignition is occurring in the first cylinder, the second cylinder, or both the first and second cylinders.

8. The system of claim 7 , wherein if the auto-ignition is detected in both the first cylinder and the second cylinder, the instructions are executable to reduce the auto-ignition by one or more of:
retarding injection timing of liquid fuel injection from the first liquid fuel injector and the second liquid fuel injector; or
increasing an amount of liquid fuel injected by the first liquid fuel injector relative to an amount of gaseous fuel supplied by the first gas admission valve and increasing an amount of liquid fuel injected by the second liquid fuel injector relative to an amount of gaseous fuel supplied by the second gas admission valve.

9. The system of claim 7 , wherein if the auto-ignition is detected in the first cylinder and not in the second cylinder, the instructions are executable to reduce the auto-ignition in the first cylinder by one or more of:
retarding injection timing of liquid fuel injection from the first liquid fuel injector while maintaining injection timing of liquid fuel injection from the second liquid fuel injector; or
increasing an amount of liquid fuel injected by the first liquid fuel injector relative to an amount of gaseous fuel supplied by the first gas admission valve while maintaining an amount of liquid fuel injected by the second liquid fuel injector relative to an amount of gaseous fuel supplied by the second gas admission valve.

10. The system of claim 9 , wherein the instructions are executable to identify a level of auto-ignition in each of the first cylinder and second cylinder based on the measured parameter, and if the level of auto-ignition in the first cylinder is above a threshold level, the instructions are executable to deactivate the first gas admission valve and increase the amount of liquid fuel injected by the first liquid fuel injector to maintain engine power.

11. The system of claim 1 , wherein the liquid fuel is diesel fuel, and wherein the first fuel system comprises a fuel tank for holding the diesel fuel, a common fuel rail, and at least one fuel injector, the diesel fuel in the fuel tank supplied to the common fuel rail by at least one fuel pump, the common fuel rail configured to supply the diesel fuel to each fuel injector of the at least one fuel injector, and wherein each fuel injector of the at least one fuel injector is coupled to a respective cylinder of the at least one cylinder of the engine.

12. The system of claim 1 , wherein the gaseous fuel is natural gas, and wherein the second fuel system comprises a fuel tank and at least one gas admission valve, each gas admission valve of the at least one gas admission valve coupled to a respective cylinder of the at least one cylinder of the engine.

13. A system, comprising:
a first fuel system operable to deliver liquid fuel to a plurality of cylinders in an engine, the first fuel system comprising a first fuel tank, a common fuel rail, and a plurality of fuel injectors, each fuel injector configured to inject liquid fuel to a respective cylinder of the plurality of cylinders;
a second fuel system operable to deliver gaseous fuel to the plurality of cylinders, the second fuel system comprising a second fuel tank and a plurality of gas admission valves, each gas admission valve configured to supply gaseous fuel to a respective cylinder of the plurality of cylinders; and
a control system storing non-transitory instructions executable to:
for each cylinder, combust a mixture of the gaseous fuel and air by injecting liquid fuel to each cylinder, the gaseous fuel and liquid fuel provided at a first ratio;
if auto-ignition of end gases after primary ignition resulting from the injection of the liquid fuel is detected in at least one cylinder of the plurality of cylinders, retard an injection timing of injection of the liquid fuel to the at least one cylinder; and
if the auto-ignition is still detected after the retarding of the injection timing, adjust at least one of an amount of the gaseous fuel or an amount of the liquid fuel provided to the at least one cylinder to a second ratio, different than the first ratio.

14. The system of claim 13 , wherein the instructions are executable to, when adjusting said at least one of the amount of the gaseous fuel or the amount of the liquid fuel to the second ratio, increase the amount of liquid fuel relative to the amount of gaseous fuel.

15. The system of claim 13 , wherein the injection of liquid fuel comprises stratified injection, and wherein the combustion of the mixture of gaseous fuel and air by the injection of liquid fuel comprises compression ignition of the liquid fuel with the mixture of gaseous fuel and air, and wherein the instructions are executable to monitor cylinder output for a first cylinder of the plurality of cylinders resulting from combustion of the gaseous fuel at the first ratio, and if the cylinder output differs from an expected output by more than a threshold amount, indicate degradation of an associated gas admission valve configured to supply the gaseous fuel to the first cylinder.

16. A method comprising:
with a first fuel system, delivering liquid fuel to a first cylinder and a second cylinder of an engine;
with a second fuel system, delivering gaseous fuel to the first c

Assignees

• Gen Electric

Inventors

• Yerace Daniel
• Klingbeil Adam Edgar
• Mischler James Robert

Classifications

• Y02T10/36

  Cross-Sectional Technologies · mapped topic

• F02D29/02

  peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers · CPC title

• F02B3/08 Primary

  Methods of operating (F02B3/12 takes precedence) · CPC title

• F02M26/23

  Layout, e.g. schematics · CPC title

• F02D19/0692

  Arrangement of multiple injectors per combustion chamber · CPC title