Gaseous fuel, EGR and air mixing device and insert

Patent metadata

Field	Value
Publication number	US-9863371-B2
Application number	US-201514840858-A
Country	US
Kind code	B2
Filing date	Aug 31, 2015
Priority date	Aug 31, 2015
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

An insert for engine intake gaseous fuel mixing device. A body defines a longitudinal axis, leading end, trailing end, and exterior surface profile from the leading to the trailing end. Supports extend radially from the body, each support extending parallel to the axis to define separate longitudinal intake passages. The exterior surface profile of the body includes a nose section in which diameter increases from a minimum value at the leading end to a maximum value at a downstream end of the nose section. The nose section is followed by a flat section and a curved tapering section in which the profile converges toward the axis at an increasing rate from the flat section in a direction of the axis toward the trailing end. The diameter at the trailing end is at least 15 percent less than a maximum diameter of the body.

First claim

What is claimed is:

1. A gaseous fuel mixing device of an air intake of an engine, the gaseous fuel mixing device comprising:
a mixer body, wherein an intake passage is defined by an interior surface within the mixer body, the mixer body including a gaseous fuel inlet for receiving gaseous fuel;
a plurality of gaseous fuel diffusion apertures in fluid communication with the gaseous fuel inlet for diffusing gaseous fuel into the intake passage; and
an insert positioned within the intake passage, the insert including
a body defining a longitudinal axis between a leading end and a trailing end, and an exterior surface extending from the leading end to the trailing end, a body length extending from the leading end to the trailing end, and
a plurality of supports extending radially from the exterior surface of the body to the interior surface defining the intake passage, each of the plurality of supports extending parallel to the longitudinal axis to divide an area between the exterior surface of the insert body and the interior surface within the mixer body into a plurality of separate longitudinally-extending intake passages,

wherein each of the plurality of longitudinal intake passages has a radial height measured from the exterior surface of the insert body to the interior surface defining the intake passage, the radial height varying along the longitudinal axis,
wherein the exterior surface of the insert body is shaped to include a nose section in which the radial height varies from a maximum value at the leading end to a minimum value at a downstream end of the nose section, and a mixing section in which the exterior surface of the insert body is flat in longitudinal cross-section, and
wherein the exterior surface of the insert body tapers down toward the longitudinal axis in a direction toward the trailing end such that the diameter of the insert body at the trailing end is at least 15 percent less than a maximum diameter of the insert body, which is at the position where the radial height is at the minimum value.

2. The gaseous fuel mixing device of claim 1 , further comprising a plurality of exhaust gas recirculation diffusion apertures in fluid communication with an exhaust of the engine for diffusing a portion of the exhaust from the engine into the intake passage downstream of the plurality of gaseous fuel diffusion apertures, but not more than 80 percent of the body length away from the leading end of the insert body.

3. The gaseous fuel mixing device of claim 1 , wherein the mixing section is a front mixing section and the exterior surface of the body further defines a rear mixing section extending from a downstream end of the front mixing section to the trailing end, the radial height continually increasing throughout the rear mixing section to the trailing end.

4. The gaseous fuel mixing device of claim 3 , wherein the rear mixing section is longer than the front mixing section as measured along the longitudinal axis.

5. The gaseous fuel mixing device of claim 3 , further comprising a plurality of exhaust gas recirculation diffusion apertures in fluid communication with an exhaust of the engine for diffusing a portion of the exhaust from the engine into the intake passage downstream of the plurality of gaseous fuel diffusion apertures, wherein the plurality of gaseous fuel diffusion apertures open into the front mixing section, and the plurality of exhaust gas recirculation diffusion apertures open into the rear mixing section.

6. The gaseous fuel mixing device of claim 1 , wherein the plurality of supports extend to the trailing end of the insert body.

7. The gaseous fuel mixing device of claim 1 , wherein the diameter of the insert body at the trailing end is at least 30 percent smaller than the maximum diameter of the insert body.

8. The gaseous fuel mixing device of claim 7 , wherein the diameter of insert body at the trailing end is at least 45 percent smaller than the maximum diameter of the insert body.

9. The gaseous fuel mixing device of claim 3 , wherein the exterior surface of the insert body has an angle of 3 degrees or less with the longitudinal axis within the front mixing section, and the exterior surface of the insert body within the rear mixing section converges toward the longitudinal axis at an increasing rate toward the trailing end.

10. The gaseous fuel mixing device of claim 1 , wherein at least one of the plurality of supports has a radially outer end secured with the interior surface defining the intake passage such that the longitudinal axis of the insert body is coaxial with a central axis of the intake passage.

11. The gaseous fuel mixing device of claim 1 , wherein a diameter of the intake passage is at least 5 percent greater than the maximum diameter of the insert body and not more than 65 percent greater than the maximum diameter of the insert body.

12. The gaseous fuel mixing device of claim 1 , wherein the plurality of gaseous fuel diffusion apertures is positioned at least 24 percent of the body length away from the leading end, but not more than 34 percent of the body length away from the leading end, and wherein the plurality of exhaust gas recirculation diffusion apertures is positioned at least 40 percent of the body length away from the leading end, but not more than 80 percent of the body length away from the leading end.

13. An insert for a gaseous fuel mixing device of an air intake of an engine, the insert comprising:
a body defining a longitudinal axis, a leading end, a trailing end, and an exterior surface profile extending from the leading end to the trailing end; and
a plurality of supports extending radially from the body, each of the plurality of supports extending parallel to the longitudinal axis to divide an intake airflow along the body into a plurality of separate longitudinal intake passages;
wherein the exterior surface profile of the body includes a nose section in which a diameter of the exterior surface profile increases from a minimum value at the leading end to a maximum value at a downstream end of the nose section, the nose section being followed sequentially in a direction toward the trailing end by a flat section and a curved tapering section in which the exterior surface profile converges toward the longitudinal axis at an increasing rate from the flat section in a direction of the longitudinal axis toward the trailing end, and
wherein the diameter of the body at the trailing end is at least 15 percent less than a maximum diameter of the body, but not more than 75 percent less than the maximum diameter of the body such that the trailing end forms a blunt trailing end that does not taper to a point.

14. The insert of claim 13 , wherein the trailing end diameter is at least 30 percent smaller than the maximum diameter defined by the body.

15. The insert of claim 13 , wherein the trailing end diameter is 40 percent smaller than the maximum diameter defined by the body.

16. The insert of claim 13 , wherein the plurality of supports extend to the trailing end of the body.

17. The insert of claim 13 , wherein each of the plurality of supports has a radially outer edge, the radially outer edges defining a diameter at least 5 percent greater than the maximum diameter of the body and not more than 65 percent greater than the maximum diameter of the body.

18. The insert of claim 13 , wherein the flat section has an angle of 3 degrees or less with the longitudinal axis.

19. The insert of claim 13 , wherein the curved tapering section is longer than the flat section as measu

Assignees

• Bosch Gmbh Robert

Inventors

• El Gammal Mohamed Moustafa
• Casarella Mark Vincent

Classifications

• Y02T10/32

  Cross-Sectional Technologies · mapped topic

• F02M35/10222

  Exhaust gas recirculation [EGR]; Positive crankcase ventilation [PCV]; Additional air admission, lubricant or fuel vapour admission · CPC title

• F02M21/04 Primary

  Gas-air mixing apparatus · CPC title

• F02D19/02

  peculiar to engines working with gaseous fuels · CPC title

• F02M21/042

  Mixer comprising a plurality of bores or flow passages · CPC title