Spray guided stratification for fueling a passive pre-chamber

Patent metadata

Field	Value
Publication number	US-12565849-B2
Application number	US-202218050342-A
Country	US
Kind code	B2
Filing date	Oct 27, 2022
Priority date	Oct 27, 2022
Publication date	Mar 3, 2026
Grant date	Mar 3, 2026

Abstract

An engine includes an engine block having a cylinder, a piston movably disposed in a main chamber of the cylinder, a prechamber adjacent to and in fluid communication with the main chamber via a prechamber nozzle, and a fuel injector in fluid communication with the main chamber, wherein the fuel injector has spray nozzles interfacing with the main chamber. The fuel injector and the prechamber are aligned such that a first nozzle of the spray nozzles is directed towards the prechamber nozzle.

First claim

What is claimed:

1 . An engine, comprising:
an engine block having a cylinder; a piston movably disposed in a main chamber of the cylinder; a prechamber adjacent to and in fluid communication with the main chamber via a prechamber nozzle; and a fuel injector having a plurality of spray nozzles in fluid communication with the main chamber, the plurality of spray nozzles comprising:
a first spray nozzle with a first spray angle; and
at least one second spray nozzle with a second spray angle,
wherein the first spray angle is larger than the second spray angle, such that the first spray angle is directed towards and aligned with the prechamber nozzle, while the second spray angle is directed towards the main chamber.

2 . The engine of claim 1 , wherein the cylinder has a cylinder head with a pent-roof angle between 5 and 25 degrees.

3 . The engine of claim 1 , further comprising a spark plug connected to and interfacing with the prechamber.

4 . The engine of claim 1 , wherein the prechamber further comprises at least one additional prechamber nozzle providing fluid communication between the prechamber and the main chamber.

5 . The engine of claim 1 , wherein the prechamber has a volume equal to between 1% and 10% of an engine clearance volume.

6 . The engine of claim 1 , wherein an external surface geometry of the prechamber may be selected from a group consisting of a flat surface, a concave surface, and a convex surface.

7 . The engine of claim 1 , wherein the prechamber is spaced a distance apart from the fuel injector.

8 . A prechamber injection method, comprising:
providing an engine comprising:
an engine block having a cylinder;
a piston movably disposed in a main chamber of the cylinder;
a prechamber adjacent to and in fluid communication with the main chamber via a prechamber nozzle; and
a fuel injector having a plurality of spray nozzles interfacing with the main chamber of the cylinder, the plurality of spray nozzles comprising:
a first spray nozzle with a first spray angle; and
at least one second spray nozzle with a second spray angle,
wherein the first spray angle is larger than the second spray angle, such that the first spray angle is directed towards and aligned with the prechamber nozzle, while the second spray angle is directed towards the main chamber;

spraying fuel from the first spray nozzle at the first spray angle in a first direction towards the prechamber nozzle such that a first amount of fuel flows through the main chamber and enters the prechamber nozzle; and while spraying fuel from the first spray nozzle, spraying fuel from the at least one second spray nozzle at the second spray angle in a second direction, different than the first direction, into the main chamber.

9 . The prechamber injection method of claim 8 , further comprising:
controlling an equivalence ratio of a fuel air mixture within the main chamber with an injection timing and an injection duration, wherein the injection timing and the injection duration are determined based, at least in part, on a charge pressure in the main chamber.

10 . The prechamber injection method of claim 9 , further comprising:
optimizing the injection timing and the injection duration for a plurality of engine speeds and a plurality of load conditions; and providing different fueling levels in the prechamber based on the optimized injection timing and injection duration.

11 . The prechamber injection method of claim 8 , further comprising creating a consistent flow direction from the main chamber to the prechamber during a compression stroke of the piston.

12 . The prechamber injection method of claim 11 , further comprising retaining fluid within the prechamber and preventing fuel leakage out of the prechamber using pressure in the main chamber from the compression stroke of the piston.

13 . The prechamber injection method of claim 8 , further comprising:
increasing a velocity and a turbulence of the fuel in the prechamber to improve mixing and a burn rate of the fuel within the prechamber; igniting the fuel with a spark plug in the prechamber; and jetting the fuel from the prechamber into the main chamber.

14 . The prechamber injection method of claim 8 , further comprising sizing the spray nozzles to achieve a desired hydraulic flow rate.

15 . The prechamber injection method of claim 8 , further comprising:
utilizing a single direct injection strategy during a late compression stroke of the piston;
wherein the single direct injection strategy comprises directing the fuel from the fuel injector into the prechamber and the main chamber a single time during a four-stroke cylinder cycle; and
igniting the fuel with a spark plug in the prechamber.

16 . The prechamber injection method of claim 8 , further comprising:
injecting fuel into the main chamber and the prechamber during an intake stroke of the piston; injecting fuel into the main chamber and the prechamber during a late compression stroke of the piston; and igniting the fuel with a spark plug in the prechamber.

17 . The prechamber injection method of claim 8 , further comprising:
performing a port fuel injection during an intake stroke of the piston; performing a direct injection of fuel into the main chamber and the prechamber during a late compression stroke of the piston; and igniting the fuel with a spark plug in the prechamber.

18 . The engine of claim 1 , wherein the first spray angle ranges from about 100 to 130 degrees and the second spray angle ranges from about 30 to 90 degrees.

19 . The prechamber injection method of claim 8 , wherein the first spray angle ranges from about 100 to 130 degrees and the second spray angle ranges from about 30 to 90 degrees.

Assignees

• Aramco Services Co
• Saudi Arabian Oil Co

Inventors

• Yu Xin
• Zhang Anqi
• Baur Andrew
• Engineer Nayan

Classifications

• F02B19/1014

  design parameters, e.g. volume, torch passage cross sectional area, length, orientation, or the like · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02D41/402

  Multiple injections · CPC title

• F02D41/3094

  the fuel injection being effected by at least two different injectors, e.g. one in the intake manifold and one in the cylinder · CPC title

• F02B23/101

  the injector being placed on or close to the cylinder centre axis, e.g. with mixture formation using spray guided concepts · CPC title