Systems and methods for equalizing backpressure in engine cylinders

Patent metadata

Field	Value
Publication number	US-10704449-B2
Application number	US-201716073117-A
Country	US
Kind code	B2
Filing date	Feb 1, 2017
Priority date	Feb 5, 2016
Publication date	Jul 7, 2020
Grant date	Jul 7, 2020

Abstract

An exhaust manifold comprises a plurality of exhaust intake conduits structured to be fluidly coupled to an engine and receive exhaust gas from a corresponding cylinder of the engine. At least one exhaust intake conduit provides a reduction in an exhaust intake conduit cross-sectional area from an inlet to an outlet. A plurality of bends are each defined by a respective one of the exhaust intake conduit outlets. An exhaust intake manifold is fluidly coupled to the exhaust intake manifold and defines an exhaust intake manifold flow axis. Each of the plurality of bends is shaped so as to define an angle of approach of exhaust gas flowing therethrough. A first angle of approach of the first bend relative to the exhaust intake manifold flow axis is smaller than a second angle of approach of an inner second bend.

First claim

What is claimed is:

1. An exhaust manifold, comprising:
a plurality of exhaust intake conduits, each of the plurality of exhaust intake conduits structured to be fluidly coupled to an engine and structured to receive exhaust gas from a corresponding cylinder of the engine, at least one of the plurality of exhaust intake conduits providing a reduction in an exhaust intake conduit cross-sectional area of the respective exhaust intake conduit from an exhaust intake conduit inlet to an exhaust intake conduit outlet of the respective exhaust intake conduit;
a plurality of bends, each of the plurality of bends defined by a respective one of the exhaust intake conduit outlets;
an exhaust intake manifold fluidly coupled to the exhaust intake conduit outlet of at least one of the plurality of exhaust intake conduits, the exhaust intake manifold defining an exhaust intake manifold flow axis; and
at least one pull-off conduit fluidly coupled to the exhaust intake manifold, at least a portion of the at least one pull-off conduit defining a pull-off conduit flow axis positioned orthogonal to each of the exhaust intake manifold flow axis and an outlet port flow axis of an outlet port fluidly coupled to the exhaust intake manifold,
wherein each of the plurality of bends is shaped so as to define an angle of approach of exhaust gas flowing through the respective exhaust intake conduit outlet, a first angle of approach of a first bend relative to the exhaust intake manifold flow axis being smaller than a second angle of approach of a second bend of the plurality of bends, wherein the first bend is structured to receive exhaust gas from a first cylinder of the engine and the second bend is structured to receive exhaust gas from a second cylinder of the engine, the first cylinder being positioned in an outer position on the engine relative to the second cylinder.

2. The exhaust manifold of claim 1 , wherein the outlet port provides a reduction in an outlet port cross-sectional area of the outlet port from an outlet port inlet to an outlet port outlet of the outlet port.

3. The exhaust manifold of claim 2 , wherein the at least one outlet port is structured to be coupled to a turbine.

4. The exhaust manifold of claim 1 , wherein the first bend of the plurality of bends defines an oval-shaped cross-section.

5. The exhaust manifold of claim 4 , wherein each of the reduction in the exhaust intake conduit cross-sectional area of each of the exhaust intake conduits, the oval-shaped cross-section of the first bend, and the angles of approach of each of the plurality of bends are defined so as to equalize a pressure pulse amplitude proximate the outlet port caused by combustion in each of the plurality of cylinders of the engine fluidly coupled to the exhaust intake manifold.

6. The exhaust manifold of claim 5 , wherein each of the reduction in the exhaust intake conduit cross-sectional area of each of the exhaust intake conduits, the oval-shaped cross-section of the first bend, and the angles of approach of each of the plurality of bends are further defined so as to maximize the pressure pulse amplitude proximate the outlet port caused by combustion in each of the plurality of cylinders of the engine fluidly coupled to the exhaust intake manifold.

7. An exhaust manifold, comprising:
a plurality of exhaust intake conduits, each of the plurality of exhaust intake conduits structured to be fluidly coupled to an engine and structured to receive exhaust gas from a corresponding cylinder of the engine, at least one of the plurality of exhaust intake conduits providing a reduction in an exhaust intake conduit cross-sectional area of the respective exhaust intake conduit from an exhaust intake conduit inlet to an exhaust intake conduit outlet of the respective exhaust intake conduit;
a plurality of bends, each of the plurality of bends defined by a respective one of the exhaust intake conduit outlets;
an exhaust intake manifold fluidly coupled to the exhaust intake conduit outlet of at least one of the plurality of exhaust intake conduits, the exhaust intake manifold defining an exhaust intake manifold flow axis,
wherein each of the plurality of bends is shaped so as to define an angle of approach of exhaust gas flowing through the respective exhaust intake conduit outlet, a first angle of approach of a first bend relative to the exhaust intake manifold flow axis being smaller than a second angle of approach of a second bend of the plurality of bends, wherein the first bend is structured to receive exhaust gas from a first cylinder of the engine and the second bend is structured to receive exhaust gas from a second cylinder of the engine, the first cylinder being positioned in an outer position on the engine relative to the second cylinder;
a first area schedule defined by a first cross-sectional area of a first of the plurality of exhaust intake conduits, the first exhaust intake conduit structured to receive exhaust gas from the first cylinder of the engine, the first area schedule defining a linear reduction in the first cross-sectional area along the first exhaust intake conduit; and
a second area schedule defined by a second cross-sectional area of a second of the plurality of exhaust intake conduits, the second exhaust intake conduit structured to receive exhaust gas from the second cylinder of the engine, the second area schedule defining a non-linear reduction in the second cross-sectional area along the second exhaust intake conduit.

8. An exhaust manifold, comprising:
a plurality of exhaust intake conduits, each of the plurality of exhaust intake conduits structured to be fluidly coupled to an engine and structured to receive exhaust gas from a corresponding cylinder of the engine, at least one of the plurality of exhaust intake conduits providing a reduction in an exhaust intake conduit cross-sectional area of the respective exhaust intake conduit from an exhaust intake conduit inlet to an exhaust intake conduit outlet of the respective exhaust intake conduit;
a plurality of bends, each of the plurality of bends defined by a respective one of the exhaust intake conduit outlets;
an exhaust intake manifold fluidly coupled to the exhaust intake conduit outlet of at least one of the plurality of exhaust intake conduits, the exhaust intake manifold defining an exhaust intake manifold flow axis,
wherein each of the plurality of bends is shaped so as to define an angle of approach of exhaust gas flowing through the respective exhaust intake conduit outlet, a first angle of approach of a first bend relative to the exhaust intake manifold flow axis being smaller than a second angle of approach of a second bend of the plurality of bends, wherein the first bend is structured to receive exhaust gas from a first cylinder of the engine and the second bend is structured to receive exhaust gas from a second cylinder of the engine, the first cylinder being positioned in an outer position on the engine relative to the second cylinder;
an outlet port fluidly coupled to the exhaust intake manifold, wherein the outlet port provides a reduction in an outlet port cross-sectional area of the outlet port from an outlet port inlet to an outlet port outlet of the outlet port; and
at least one pull-off conduit fluidly coupled to the at least one exhaust intake manifold, wherein a pull-off conduit first portion of the at least one pull-off conduit defines a reducing pull-off conduit cross-sectional area from a pull-off conduit first portion inlet to a pull-off conduit first portion outlet of the pull-off conduit first portion.

9. The exhaust manifold of claim 8 , further comprising:
a diffuser,
wherein a pull-off conduit second portion of the at least one pull off-conduit is fluidly

Assignees

• Cummins Inc

Inventors

• Mohr Daniel J
• Pavlov Bogdan V
• Ajotikar Nikhil J
• Chen Yi-Cheng
• Eckroth David

Classifications

• F02M35/104

  Intake manifolds · CPC title

• F02M35/10222

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

• F02M35/10216

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

• F02M35/10157

  Supercharged engines · CPC title

• F02M35/10052

  special shapes or arrangements of plenum chambers; Constructional details · CPC title