Ducted combustion systems utilizing flow field preparation

Patent metadata

Field	Value
Publication number	US-10119456-B2
Application number	US-201715402811-A
Country	US
Kind code	B2
Filing date	Jan 10, 2017
Priority date	Jan 10, 2017
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

A ducted combustion system includes a combustion chamber and a fuel injector in fluid connection with the combustion chamber, which includes an orifice opening from an injector tip of the fuel injector, the orifice injecting fuel into the combustion chamber as a fuel jet, the fuel jet flowing, within the combustion chamber, in a fuel flow direction. The system includes at least one duct disposed within the combustion chamber, the at least one duct being disposed such that the fuel jet, at least partially, enters one of the at least one ducts upon being injected into the combustion chamber. The at least one duct may be configured for having a flow field air stream within the duct, prior to entrance of the fuel jet, the flow field air stream having a flow direction that is substantially similar to the fuel flow direction.

First claim

What is claimed is:

1. A ducted combustion system, comprising:
a combustion chamber defined as an enclosure bound at a first end by a flame deck surface of a cylinder head of an internal combustion engine, and bound at a second end by a piston top surface of a piston disposed within the internal combustion engine;
a fuel injector in fluid connection with the combustion chamber and including at least one orifice opening from an injector tip of the fuel injector, the at least one orifice injecting fuel into the combustion chamber as at least one fuel jet, the at least one fuel jet flowing, within the combustion chamber, in a fuel flow direction;
at least one duct disposed within the combustion chamber between the flame deck surface and the piston top surface, the at least one duct being disposed such that the at least one fuel jet, at least partially, enters the at least one duct upon being injected into the combustion chamber, the at least one duct configured for having a flow field air stream within the duct, prior to entrance of the at least one fuel jet, the flow field air stream having a flow direction, the flow direction being substantially similar to the fuel flow direction; and
at least one duct support structure supporting the at least one duct within the combustion chamber, the at least one duct support structure being configured to provide the flow field air stream within the duct and to direct the flow field air stream in the flow direction.

2. The ducted combustion system of claim 1 , wherein the at least one duct support structure is an airflow channel.

3. The ducted combustion system of claim 2 , wherein the airflow channel is in fluid communication with a second cylinder of the internal combustion engine and air for the flow field air stream is communicated from the second cylinder to the airflow channel.

4. The ducted combustion system of claim 3 , wherein the air for the airflow channel is communicated from the second cylinder to the airflow channel on a downward stroke of a second piston of the second cylinder.

5. The ducted combustion system of claim 2 , further comprising an air compressor in fluid communication with the airflow channel and air for the flow field air stream is generated by the air compressor and communicated to the airflow channel.

6. The ducted combustion system of claim 5 , further comprising a controller, the controller associated with the air compressor and providing control signals to the air compressor to control air generation for generating the flow field air stream.

7. The ducted combustion system of claim 6 , further comprising a flow sensor associated with the fuel injector, the controller using flow signals provided by the flow sensor to determine the control signals provided to the air compressor to control air generation for generating the flow field air stream.

8. The ducted combustion system of claim 1 , further comprising a plurality of valves located in the cylinder head, the plurality of valves including at least one air intake valve and at least one exhaust valve, and
wherein each of the at least one ducts is circumferentially disposed between two members of the plurality of valves.

9. An internal combustion engine, comprising:
an engine block including a first cylinder bore;
a cylinder head having a flame deck surface disposed at one end of the first cylinder bore;
a piston connected to a crankshaft and configured to reciprocate within the cylinder bore, the piston having a piston top surface facing the flame deck surface such that a combustion chamber is defined within the first cylinder bore bound at a first end by the flame deck surface and at a second end by the piston top surface;
a fuel injector in fluid connection with the combustion chamber and including at least one orifice opening from an injector tip of the fuel injector, the at least one orifice injecting fuel into the combustion chamber as at least one fuel jet, the at least one fuel jet flowing, within the combustion chamber, in a fuel flow direction;
at least one duct disposed within the combustion chamber between the flame deck surface and the piston top surface, the at least one duct being disposed such that the at least one fuel jet, at least partially, enters the at least one duct upon being injected into the combustion chamber, the at least one duct configured for having a flow field air stream within the duct, prior to entrance of the at least one fuel jet, the flow field air stream having a flow direction, the flow direction being substantially similar to the fuel flow direction; and
at least one duct support structure supporting the at least one duct within the combustion chamber, the at least one duct support structure being configured to provide the flow field air stream within the duct and direct the flow field air stream in the flow direction.

10. The internal combustion engine of claim 9 , wherein the at least one duct support structure is an airflow channel.

11. The internal combustion engine of claim 10 , wherein the airflow channel is in fluid communication with a second cylinder of the internal combustion engine and air for the flow field air stream is communicated from the second cylinder to the airflow channel.

12. The internal combustion engine of claim 11 , wherein the air for the airflow channel is communicated from the second cylinder to the airflow channel on a downward stroke of a second piston of the second cylinder.

13. The internal combustion engine of claim 10 , further comprising an air compressor in fluid communication with the airflow channel and air for the flow field air stream is generated by the air compressor and communicated to the airflow channel.

14. The internal combustion engine of claim 13 , further comprising a controller, the controller associated with the air compressor and providing control signals to the air compressor to control air generation for generating the flow field air stream.

15. The internal combustion engine of claim 14 , further comprising a flow sensor associated with the fuel injector, the controller using flow signals provided by the flow sensor to determine the control signals provided to the air compressor to control air generation for generating the flow field air stream.

16. A method for operating a combustion system, comprising:
generating a flow field air stream in a duct using a duct support structure, the duct disposed within a combustion chamber of an internal combustion engine and being supported within the combustion chamber by the duct support structure, the combustion chamber defined as an enclosure bound at a first end by a flame deck of a cylinder of the internal combustion engine and bound at a second end by a piston top surface of a piston disposed within the internal combustion engine, the flow field air stream having a flow direction;
injecting a fuel jet into the combustion chamber;
directing the fuel jet, at least partially, into the duct, the fuel jet flowing, within the combustion chamber, in a fuel flow direction that is substantially similar to the flow direction.

17. The method of claim 16 , wherein the duct support structure is an airflow channel and wherein the method further comprises directing air for the flow field air stream to the duct, in the flow direction, via the airflow channel.

18. The method of claim 17 , further comprising:
generating air for the flow field air stream by a source outside of the combustion chamber; and
communicating the air for the flow field air stream to the airflow channel.

Assignees

• Caterpillar Inc

Inventors

• Fitzgerald Russell P

Classifications

• F02B23/00 Primary

  Other engines characterised by special shape or construction of combustion chambers to improve operation (engines with incandescent chambers F02B9/08) · CPC title

• F02F1/242

  Arrangement of spark plugs or injectors · CPC title

• F02D41/3005

  Details not otherwise provided for · CPC title

• F02M57/04

  the devices being combustion-air intake or exhaust valves · CPC title

• F02M61/1806

  characterised by the arrangement of discharge orifices, e.g. orientation or size · CPC title