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

Patent metadata

Field	Value
Publication number	US-10767587-B2
Application number	US-201815962255-A
Country	US
Kind code	B2
Filing date	Apr 25, 2018
Priority date	Aug 2, 2016
Publication date	Sep 8, 2020
Grant date	Sep 8, 2020

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:
in response to a request for water injection, selecting, based on engine operating conditions of an engine including an engine load threshold, a location for water injection from among an intake port of each cylinder of the engine, directly into each cylinder of the engine, and multiple manifolds of the engine, each upstream of a different group of cylinders; and
injecting an amount of water into the selected location,
where injecting the amount of water at the multiple manifolds, when the multiple manifolds is the selected location, includes injecting a first amount of water into a first manifold upstream of a first group of cylinders and a different, second amount of water into a second manifold 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 selecting the multiple manifolds for water injection in response to engine load above the threshold load and, following injecting the first amount of water into the first manifold and the second amount of water into the second manifold, 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 2 , further comprising selecting to additionally inject water directly into each cylinder of the engine in response to engine load above the threshold load and water injection at the multiple manifolds reaching or being above an upper threshold amount.

7. The method of claim 1 , further comprising selecting the multiple manifolds for water injection, wherein injecting the first amount of water into the first manifold 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, 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 include 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 operating conditions of the second group include 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.

9. The method of claim 1 , further comprising selecting the intake port of each cylinder of the engine for injecting the amount of water in response to engine load below the threshold load.

10. A method, comprising:
in response to a water injection request:
during a first operation, injecting water into an intake port of an engine cylinder; and
during a second operation,
injecting a first amount of water upstream of a first group of engine cylinders and injecting a second amount of water upstream of a second group of engine cylinders, where the first amount is based on a first operating condition of the first group of engine cylinders and the second amount is based on a first operating condition of the second group of engine 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 different, 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 different, 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 different, second operating condition of the first group and the second group of cylinders and adjusting the second amount based on both the different, 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 a

Assignees

• Ford Global Tech Llc

Inventors

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

Classifications

• F02M25/0227

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

• F02D41/1444 Primary

  characterised by the characteristics of the combustion gases · CPC title

• F02D41/0085 Primary

  Balancing of cylinder outputs, e.g. speed, torque or air-fuel ratio · CPC title

• F02D41/0082

  per groups or banks (F02D41/0087 takes precedence) · CPC title

• F02D41/0025

  Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures · CPC title