Fuel admission tube for enhanced mixing in gaseous fuel engine and engine operating method

Patent metadata

Field	Value
Publication number	US-12448939-B1
Application number	US-202418639186-A
Country	US
Kind code	B1
Filing date	Apr 18, 2024
Priority date	Apr 18, 2024
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

An engine system includes an engine housing forming a plurality of intake ports, and a plurality of fuel admission tubes each forming a fuel passage and at least one mixing air opening fluidly connected to the fuel passage between a first tube end and a terminal end surface of a second tube end. The mixing air opening may be formed in an end cap of the fuel admission tube. A plurality of mixing air openings in a fuel admission tube may have at least one of a circumferential distribution or an axial distribution that is biased in a direction of an incoming flow of intake air. Related apparatus and methodology is also disclosed.

First claim

What is claimed is:

1. An engine system comprising:
an engine housing forming a plurality of intake ports each fluidly connecting between an upstream intake air feed opening and a plurality of intake valve openings, such that a feed of air through each respective one of the plurality of intake ports enters a respective cylinder of the engine system through the respective plurality of intake valve openings, the engine housing further forming a common air cavity fluidly connecting the upstream intake air feed opening to the plurality of intake ports, and each of the plurality of fuel admission tubes extends through the common air cavity;
a plurality of fuel admission tubes each forming a fuel passage extending from a first tube end forming a fuel inlet, to a second tube end having a terminal end surface extending circumferentially around a fuel outlet; and
each of the plurality of fuel admission tubes further including at least one mixing air opening formed therein and fluidly connected to the fuel passage at a location that is between the first tube end and the terminal end surface, the at least one mixing air opening being configured to admit some of the intake air therethrough, and the at least one mixing air opening includes a plurality of mixing air openings having both an axial distribution and a circumferential distribution in the fuel admission tube.

2. The engine system of claim 1 wherein each of the plurality of fuel admission tubes defines an outgoing fuel axis extending into one of the plurality of intake ports.

3. The engine system of claim 1 wherein the plurality of mixing air openings are biased in at least one of the axial distribution or the circumferential distribution toward a direction of incoming intake air flow from the upstream intake air opening.

4. A method of operating an engine system comprising:
feeding intake air from an upstream intake air feed opening through a common air cavity to a plurality of intake ports in an engine housing;
feeding a gaseous fuel through a plurality of fuel passages in a plurality of fuel admission tubes each extending through the common air cavity to one of the plurality of intake ports;
admitting some of the intake air through at least one mixing air opening in each of the plurality of fuel admission tubes into the respective fuel passage at a location that is fluidly between a fuel inlet and a fuel outlet of the respective fuel admission tube; and
conveying the intake air and gaseous fuel from each of the plurality of intake ports into a plurality of engine cylinders for combustion through a first intake valve opening located downstream from the intake air feed opening and through a second intake valve opening located downstream from the first intake valve opening.

5. The method of claim 4 wherein the gaseous fuel includes gaseous molecular hydrogen.

6. The method of claim 4 wherein the at least one mixing air opening includes a plurality of mixing air openings having an axial distribution in the respective fuel admission tube.

7. The method of claim 6 wherein the plurality of mixing air openings have a circumferential distribution in the respective fuel admission tube.

8. The method of claim 7 wherein the plurality of mixing air openings are biased in at least one of the axial distribution or the circumferential distribution in the respective fuel admission tube toward a direction of incoming intake air flow from the upstream intake air feed opening.

9. The method of claim 4 wherein the admitting some of the intake air includes admitting the intake air through a plurality of mixing air openings formed in a plurality of end caps of the plurality of fuel admission tubes.

10. A fuel admission tube for a gaseous fuel engine comprising:
a tube body including an outer tube surface, and an inner tube surface forming a fuel passage defining a curvilinear tube axis line and extending between a first axial end including a connector forming a fuel inlet, and a second axial end forming a fuel outlet; and
the tube body including a plurality of mixing air openings formed therein and fluidly connected to the fuel passage;
wherein the plurality of mixing air openings have an axial distribution.

11. The fuel admission tube of claim 10 wherein the plurality of mixing air openings includes a plurality of mixing air openings formed in the tube body between the first axial end and the second axial end and having a circumferential distribution around the curvilinear tube axis line.

12. The fuel admission tube of claim 11 wherein at least one of the circumferential distribution or the axial distribution includes a biased distribution.

13. A fuel admission tube for a gaseous fuel engine comprising:
a tube body including an outer tube surface, and an inner tube surface forming a fuel passage defining a curvilinear tube axis line and extending between a first axial end including a connector forming a fuel inlet, and a second axial end forming a fuel outlet; and
the tube body including at least one mixing air opening formed therein and fluidly connected to the fuel passage;
wherein the tube body includes a conduit piece and an attached end cap forming the fuel outlet, and the at least one mixing air opening includes a plurality of mixing air openings formed in the end cap.

14. The fuel admission tube of claim 13 wherein the at least one mixing air opening is angularly oriented relative to the curvilinear tube axis line.

Assignees

• Caterpillar Inc

Inventors

• John Bobby
• Anders Jonathan W
• Kavuri Naga Krishna Chaitanya
• Barnes William

Classifications

• F02M35/1045

  characterised by the charge distribution between the cylinders/combustion chambers or its homogenisation · CPC title

• F02M21/0278

  Port fuel injectors for single or multipoint injection into the air intake system · CPC title

• F02M21/0281

  Adapters, sockets or the like to mount injection valves onto engines; Fuel guiding passages between injectors and the air intake system or the combustion chamber · CPC title

• F02M35/10216 Primary

  Fuel injectors; Fuel pipes or rails; Fuel pumps or pressure regulators · CPC title

• F02M61/1813 Primary

  Discharge orifices having different orientations with respect to valve member direction of movement, e.g. orientations being such that fuel jets emerging from discharge orifices collide with each other · CPC title