Ducted combustion systems utilizing duct structures

• US 9,803,538 B2
• Filed: 04/13/2015
• Issued: 10/31/2017
• Est. Priority Date: 04/13/2015
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Anders, Jonathan, Svensson, Kenth, John, Bobby, Koci, Chad, Gehrke, Christopher, Martin, Glen, Bazyn, Timothy
• Primary Examiner(s): Vo, Hieu T
• Assistant Examiner(s): Castro, Arnold
• Application Number:
  US14/685,295
• Publication Number:
  US 20160298529A1
• Time in Patent Office: 932 Days
• CPC Class Codes: F02B 23/02 with compression ignition
• CPC Class Codes: F02B 23/0627 having additional bores or grooves machined into the piston for guiding air or charge flow to the piston bowl
• CPC Class Codes: F02B 23/0648 Means or methods to improve the spray dispersion, evaporation or ignition
• CPC Class Codes: F02B 23/0651 the fuel spray impinging on reflecting surfaces or being specially guided throughout the combustion space
• CPC Class Codes: F02F 1/24 Cylinder heads
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A ducted combustion system is disclosed. The ducted combustion system includes a combustion chamber bound by a flame deck surface of a cylinder head of an internal combustion engine and by a piston top surface of a piston disposed within the internal combustion engine. The system includes a fuel injector including a plurality of orifices, the plurality of orifices injecting fuel into the combustion chamber as a plurality of fuel jets. The system includes a duct structure defining a plurality of ducts and disposed within the combustion chamber between the flame deck surface and the piston top surface, the plurality of ducts being disposed such that each of the plurality of fuel jets at least partially enters one of the plurality of ducts upon being injected into the combustion chamber.

Claims

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 a plurality of orifices in an injector tip of the fuel injector, the plurality of orifices injecting fuel into the combustion chamber as a plurality of fuel jets; and

a generally conical duct structure defining a plurality of ducts and disposed within the combustion chamber between the flame deck surface and the piston top surface, the plurality of ducts being disposed such that each of the plurality of fuel jets at least partially enters one of the plurality of ducts upon being injected into the combustion chamber.

2. The ducted combustion system of claim 1, wherein the duct structure has an outer surface, the outer surface defining a slit.

3. The ducted combustion system of claim 1, wherein at least one of the plurality of ducts has an opening width and at least one of the plurality of fuel jets has a jet width when each of the plurality of fuel jets at least partially enters one of the plurality of ducts upon being injected into the combustion chamber, and

wherein the opening width is greater than the jet width.

4. The ducted combustion system of claim 1, wherein the generally conical disc structure of the duct structure includes a first disc having a first radius at openings of the plurality of ducts and a second radius at an outlet of each of the plurality of ducts, the second radius being greater than the first radius.

5. The ducted combustion system of claim 1, wherein the duct structure is positioned in direct alignment with the plurality of orifices.

6. The ducted combustion system of claim 4, wherein each of the plurality of ducts has an opening and each of the openings is positioned in alignment with one of the plurality of orifices.

7. The ducted combustion system of claim 4, wherein the generally conical shaped disc structure includes a second disc, the second disc having a third radius proximate to the openings of the plurality of ducts and a fourth radius proximate to the outlets of the plurality of ducts, the fourth radius being greater than the third radius,

wherein the first radius is greater than the third radius;

wherein the second radius is greater than the fourth radius; and

wherein the ducts are defined as space between the first disc and the second disc.

8. The ducted combustion system of claim 7, wherein at least one of the generally conical disc structure and the second disc has a radius that varies with respect to a circumferential position of the generally conical disc structure and able to be rotated about an injector axis.

9. The ducted combustion system of claim 1, wherein the duct structure has an outer surface, the outer surface defining a plurality of perforations.

10. The ducted combustion system of claim 9, wherein the outer surface has a plurality of duct walls, each of the plurality of duct walls defining a wall of one of the plurality of ducts, and

wherein each of the plurality of perforations is defined on one of the plurality of duct walls.

11. An internal combustion engine, comprising:

an engine block having at least one cylinder bore;

a cylinder head having a flame deck surface disposed at one end of the 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 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 a plurality of orifices in an injector tip of a fuel injector, the plurality of orifices injecting fuel into the combustion chamber as a plurality of fuel jets; and

a duct structure defining a plurality of ducts and disposed within the combustion chamber between the flame deck surface and the piston top surface, the plurality of ducts being disposed such that each of the plurality of fuel jets at least partially enters one of the plurality of ducts upon being injected into the combustion chamber, wherein the duct structure is a generally conical disc structure.

12. The internal combustion engine of claim 11, wherein at least one of the plurality of ducts has an opening width and at least one of the plurality of fuel jets has a jet width when each of the plurality of fuel jets at least partially enters one of the plurality of ducts upon being injected into the combustion chamber, and

wherein the opening width is greater than the jet width.

13. The internal combustion engine of claim 11, wherein the generally conical disc structure of the duct structure includes a first disc having a first radius at openings of the plurality of ducts and a second radius at outlets of the plurality of ducts, the second radius being greater than the first radius.

14. The internal combustion engine of claim 13, wherein the generally conical shaped disc structure includes a second disc, the second disc having a third radius proximate to the openings of the plurality of ducts and a fourth radius proximate to the outlets of the plurality of ducts, the fourth radius being greater than the third radius,

wherein the first radius is greater than the third radius;

wherein the second radius is greater than the fourth radius; and

wherein the ducts are defined as space between the first disc and the second disc.

15. A method for operating a combustion system, comprising:

injecting a plurality of fuel jets into a combustion chamber of an internal combustion engine, the combustion chamber defined as an enclosure bound at a first end by a flame deck of a cylinder 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;

directing each of the plurality of fuel jets, at least partially, into respective members of a plurality of ducts, each of the plurality of ducts being defined within a generally conical shaped duct structure, to provide a substantially uniform mixture of fuel and air within each of the plurality of fuel jets.

16. The method of claim 15, further comprising mixing fuel from the plurality of fuel jets and air within the plurality of ducts, once the plurality of fuel jets has entered the plurality of ducts.