Methods and system for injecting water at different groups of cylinders of an engine

Patent metadata

Field	Value
Publication number	US-9976502-B2
Application number	US-201615226615-A
Country	US
Kind code	B2
Filing date	Aug 2, 2016
Priority date	Aug 2, 2016
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

Methods and systems are provided for adjusting an amount of water injected upstream of a group of cylinders based on a determined maldistribution of water among cylinders during a water injection event. In one example, a method may include injecting a first amount of water upstream of a first group of cylinders and a different, second amount of water upstream of a second group of cylinders based on operating conditions of the respective cylinder groups. Further, the method may include adjusting water injection and engine operating parameters in response the evaporated and/or condensed portion of water.

First claim

The invention claimed is:

1. A method, comprising:
injecting a first amount of water upstream of a first group of cylinders and a different, second amount of water upstream of a second group of cylinders, the first amount determined based on operating conditions of the first group and the second amount determined based on operating conditions of the second group.

2. The method of claim 1 , further comprising determining a first portion of the first amount of water that vaporized based on a change in temperature upstream of the first group of cylinders following the injecting the first amount of water and determining a second portion of the first amount of water that remained liquid based on the injected first amount of water and the determined first portion of the first amount of water.

3. The method of claim 2 , further comprising determining a first portion of the second amount of water that vaporized based on a change in temperature upstream of the second group of cylinders following the injecting the second amount of water and determining a second portion of the second amount of water that remained liquid based on the injected second amount of water and the determined first portion of the second amount of water.

4. The method of claim 3 , further comprising adjusting the determined first portion and second portion of the first amount of water based on the determined first portion and second portion of the second amount of water and adjusting the determined first portion and second portion of the second amount of water based on the determined first portion and second portion of the first amount of water.

5. The method of claim 4 , further comprising adjusting the first amount of water based on the adjusted first portion and second portion of the first amount of water and adjusting the second amount of water based on the adjusted first portion and second portion of the second amount and during a subsequent water injection event, injecting the adjusted first amount of water upstream of the first group of cylinders and injecting the adjusted second amount of water upstream of the second group of cylinders.

6. The method of claim 1 , wherein injecting the first amount of water upstream of the first group of cylinders includes pulsing a first water injector disposed upstream of the first group of cylinders to deliver the first amount of water, where the pulsing is synchronized to an intake valve opening timing of each cylinder of the first group of cylinders.

7. The method of claim 6 , wherein an initial amount of water delivered by and a timing of each pulse is based on an engine mapping of cylinders within the first cylinder group and further comprising adjusting the initial amount of water delivered by and timing of each pulse based on outputs of knock sensors coupled to each cylinder of the first cylinder group following the injecting.

8. The method of claim 1 , wherein the operating conditions of the first group includes one or more of mass air flow to the first group of cylinders, a pressure at the first group of cylinders, a fuel injection amount injected into the first group of cylinders, a temperature of the first group of cylinders, and a knock level indicated by a knock sensor coupled to each cylinder of the first group of cylinders.

9. The method of claim 1 , wherein the operating conditions of the second group includes one or more of mass air flow to the second group of cylinders, a pressure at the second group of cylinders, a fuel injection amount injected into the second group of cylinders, a temperature of the second group of cylinders, and a knock level indicated by a knock sensor coupled to each cylinder of the second group of cylinders.

10. A method, comprising:
injecting a first amount of water upstream of a first group of cylinders and injecting a second amount of water upstream of a second group of cylinders, where the first amount is based on a first operating condition of the first group of cylinders and the second amount is based on a first operating condition of the second group of cylinders;
adjusting the first amount based on a different, second operating condition of the second group of cylinders; and
adjusting the second amount based on a different, second operating condition of the first group of cylinders.

11. The method of claim 10 , wherein the first operating condition of the first group of cylinders includes one or more of mass air flow to the first group of cylinders, a pressure at the first group of cylinders, a fuel injection amount injected into the first group of cylinders, a temperature of the first group of cylinders, and a knock level indicated by a knock sensor coupled to each cylinder of the first group of cylinders and wherein the first operating condition of the second group of cylinders includes one or more of mass air flow to the second group of cylinders, a pressure at the second group of cylinders, a fuel injection amount injected into the second group of cylinders, a temperature of the second group of cylinders, and a knock level indicated by a knock sensor coupled to each cylinder of the second group of cylinders.

12. The method of claim 10 , wherein the second operating condition of the first group of cylinders includes a determined first portion of the first amount of water that vaporized and a determined second portion of the first amount of water that remained liquid and wherein the second operating condition of the second group of cylinders includes a determined first portion of the second amount of water that vaporized and a determined second portion of the second amount of water that remained liquid.

13. The method of claim 12 , further comprising adjusting the first amount based on both the second operating condition of the first group and the second group of cylinders and adjusting the second amount based on both the second operating condition of the first group and the second group of cylinders.

14. The method of claim 12 , further comprising adjusting an operating parameter of the first group of cylinders based on the determined first portion and second portion of the first amount of water and the determined first portion and second portion of the second amount of water, where the operating parameter is one or more of spark timing, a fuel injection amount, and an airflow level to the engine.

15. The method of claim 14 , wherein adjusting the operating parameter further includes individually adjusting the operating parameter for each cylinder of the first group of cylinders based on a difference in output of knock sensors coupled to each cylinder of the first group of cylinders.

16. The method of claim 10 , further comprising adjusting a pulse width and timing of injection of the first amount based on outputs of knock sensors coupled to each cylinder of the first group of cylinders and adjusting a pulse width and timing of injection of the second amount based on outputs of knock sensors coupled to each cylinder of the second group of cylinders.

17. The method of claim 10 , wherein the first amount of water is different than the second amount of water.

18. A system, comprising:
a first water injector coupled to a common intake manifold of a first group of cylinders;
a second water injector coupled to a common intake manifold of a second group of cylinders; and
a controller including non-transitory memory with computer readable instructions for: determining a first amount of water to inject via the first water injector based on a first operating condition of the first group of cylinders and a second amount of wat

Assignees

• Ford Global Tech Llc

Inventors

• Hakeem Mohannad
• Surnilla Gopichandra
• House Christopher
• Shelby Michael Howard
• Ulrey Joseph Norman

Classifications

• F02D2200/0411

  Volumetric efficiency · CPC title

• F02D35/023

  by determining the cylinder pressure · CPC title

• F02D2041/1472

  the characteristics being a humidity or water content of the exhaust gases · CPC title

• F02D2200/0614

  Actual fuel mass or fuel injection amount · CPC title

• F02M25/0227

  Control aspects; Arrangement of sensors; Diagnostics; Actuators · CPC title