U.S. patent application number 11/094526 was filed with the patent office on 2006-10-05 for burner assembly for particulate trap regeneration.
This patent application is currently assigned to Solar Turbines Incorporated. Invention is credited to Leonel Arellano, Anthony Fahme, Alan Kubasco, Vu Phi, Kenneth Smith.
Application Number | 20060218902 11/094526 |
Document ID | / |
Family ID | 36283967 |
Filed Date | 2006-10-05 |
United States Patent
Application |
20060218902 |
Kind Code |
A1 |
Arellano; Leonel ; et
al. |
October 5, 2006 |
Burner assembly for particulate trap regeneration
Abstract
An exhaust treatment system is provided. The system may include
a particulate trap configured to remove one or more types of
particulate matter from an exhaust flow, the exhaust flow including
at least a portion of a totality of exhaust gases produced by an
engine. The system may further include a burner assembly configured
to increase a temperature of gases in the exhaust flow at a
location upstream from the particulate trap. The burner assembly
may include an exhaust inlet oriented in a direction along a first
axis and configured to direct the exhaust flow into the burner
assembly and an exhaust outlet oriented in a direction along a
second axis at an angle relative to the first axis, the exhaust
outlet being configured to direct the exhaust flow out of the
burner assembly toward the particulate trap. The burner assembly
may also include a fuel injector having a longitudinal axis in
substantial alignment with the second axis. In addition, the burner
assembly may include a cylindrical combustion chamber member
defining a combustion chamber, having a longitudinal axis in
substantial alignment with the longitudinal axis of the fuel
injector, and configured to house a flame that is fueled by the
fuel injector within the combustion chamber. The burner assembly
may further include an exhaust flow distribution member configured
to substantially evenly distribute exhaust about the combustion
chamber member and in a heat exchange relation to the combustion
chamber member.
Inventors: |
Arellano; Leonel; (Poway,
CA) ; Phi; Vu; (San Diego, CA) ; Fahme;
Anthony; (Chula Vista, CA) ; Kubasco; Alan;
(San Diego, CA) ; Smith; Kenneth; (San Diego,
CA) |
Correspondence
Address: |
CATERPILLAR/FINNEGAN, HENDERSON, L.L.P.
901 New York Avenue, NW
WASHINGTON
DC
20001-4413
US
|
Assignee: |
Solar Turbines Incorporated
|
Family ID: |
36283967 |
Appl. No.: |
11/094526 |
Filed: |
March 31, 2005 |
Current U.S.
Class: |
60/295 ;
60/297 |
Current CPC
Class: |
F01N 2240/14 20130101;
F23D 11/103 20130101; F23D 2900/21003 20130101; F01N 2260/04
20130101; F01N 2240/02 20130101; F01N 2470/18 20130101; F01N 13/08
20130101; F23D 91/02 20150701; F01N 2470/04 20130101; F01N 3/025
20130101 |
Class at
Publication: |
060/295 ;
060/297 |
International
Class: |
F01N 3/00 20060101
F01N003/00 |
Claims
1. An exhaust treatment system, comprising: a particulate trap
configured to remove one or more types of particulate matter from
an exhaust flow, the exhaust flow including at least a portion of a
totality of exhaust gases produced by an engine; and a burner
assembly configured to increase a temperature of the exhaust flow
at a location upstream from the particulate trap, the burner
assembly including: an exhaust inlet oriented in a direction along
a first axis and configured to direct the exhaust flow into the
burner assembly; an exhaust outlet oriented in a direction along a
second axis at an angle relative to the first axis, the exhaust
outlet being configured to direct the exhaust flow out of the
burner assembly toward the particulate trap; a fuel injector having
a longitudinal axis in substantial alignment with the second axis;
a cylindrical combustion chamber member defining a combustion
chamber, having a longitudinal axis in substantial alignment with
the longitudinal axis of the fuel injector, and configured to house
a flame that is fueled by the fuel injector within the combustion
chamber; and an exhaust flow distribution member configured to
substantially evenly distribute exhaust about the combustion
chamber member and in a heat exchange relation to the combustion
chamber member.
2. The system of claim 1, wherein the first axis is substantially
perpendicular to the second axis.
3. The system of claim 1, wherein the exhaust flow distribution
member is positioned about the combustion chamber member.
4. The system of claim 1, wherein the combustion chamber member
includes an upstream end and a downstream end and the exhaust
outlet includes a conical portion having holes in it, the conical
portion having an upstream end attached to the downstream end of
the combustion chamber member and a downstream end, wider than the
upstream end of the conical portion and through which all exhaust
flow directed through the burner assembly passes.
5. The system of claim 4, further including a baffle located within
the conical portion of the exhaust outlet and configured to
stabilize the flame that is fueled by the fuel injector.
6. The system of claim 5, wherein the baffle includes holes about
its periphery.
7. The system of claim 1, wherein the fuel injector includes a fuel
conduit configured to deliver fuel to the combustion chamber, the
burner assembly being configured to introduce fresh air to the fuel
injector upstream of the exhaust flow and downstream of a location
at which the fuel leaves the fuel conduit.
8. The system of claim 7, wherein the fuel injector further
includes an outer annular wall about the fuel conduit and defining
an annular cavity, the outer annular wall including longitudinal
slots through which the fresh air is introduced to the annular
cavity, the slots being angled so as to impart a rotational motion
of the fresh air within the annular cavity.
9. A work machine having an exhaust treatment system, comprising:
an exhaust gas producing engine; an exhaust conduit for directing
an exhaust flow to a particulate trap configured to remove one or
more types of particulate matter from the exhaust flow, the exhaust
flow including at least a portion of a totality of exhaust gases
produced by the engine; and a burner assembly configured to
increase a temperature of the exhaust flow at a location upstream
from the particulate trap, the burner assembly including: an
exhaust inlet configured to direct the exhaust flow into the burner
assembly; an exhaust outlet configured to direct the exhaust flow
out of the burner assembly toward the particulate trap, the exhaust
outlet being oriented in a direction substantially perpendicular to
the exhaust inlet; a fuel injector having a longitudinal axis in
substantial alignment with the direction in which the exhaust
outlet is oriented; a cylindrical combustion chamber member
defining a combustion chamber, having a longitudinal axis in
substantial alignment with the longitudinal axis of the fuel
injector, and configured to house a flame that is fueled by the
fuel injector within the combustion chamber; and an exhaust flow
distribution member positioned about the combustion chamber member
and configured to substantially evenly distribute the exhaust flow
about the combustion chamber member and in a heat exchange relation
to the combustion chamber member.
10. The work machine of claim 9, wherein the combustion chamber
member includes an upstream end and a downstream end and the
exhaust outlet includes a conical portion having holes in it, the
conical portion having an upstream end attached to the downstream
end of the combustion chamber member and a downstream end, wider
than the upstream end of the conical portion, and through which all
exhaust flow directed through the burner assembly passes.
11. The work machine of claim 10, further including a baffle
located within the conical portion of the exhaust outlet and
configured to stabilize the flame that is fueled by the fuel
injector.
12. The work machine of claim 11, wherein the baffle includes holes
about its periphery.
13. The work machine of claim 9, wherein the fuel injector includes
a fuel conduit configured to deliver fuel to the combustion
chamber, the burner assembly being configured to introduce fresh
air to the fuel injector upstream of the exhaust flow and
downstream of a location at which the fuel leaves the fuel
conduit.
14. The system of claim 13, wherein the fuel injector further
includes an outer annular wall, about the fuel conduit, and
defining an annular cavity, the annular wall including longitudinal
slots through which the fresh air is introduced to the annular
cavity, the slots being angled so as to impart a rotational motion
on the fresh air within the annular cavity.
15. A method of regenerating an exhaust particulate trap,
comprising: directing an exhaust flow, produced by an engine, into
a burner assembly, the exhaust flow including at least a portion of
a totality of exhaust gases produced by an engine, the burner
assembly being located upstream from a particulate trap configured
to remove one or more types of particulate matter from the exhaust
flow; directing the exhaust flow through an exhaust flow
distribution member and thereby substantially evenly distributing
the exhaust flow about a combustion chamber member to remove heat
from the combustion chamber member, the heat being created by a
flame within the combustion chamber member; heating the exhaust
flow in stages as the exhaust flow passes through the burner
assembly by exposing a portion of the exhaust flow to the flame at
a first stage and exposing additional portions of the exhaust flow
to the flame at each subsequent stage to create a heated exhaust
flow; directing the heated exhaust flow out of the burner assembly
and to the particulate trap to thereby increase a temperature of
the particulate trap.
16. The method of claim 15, wherein the directing of the exhaust
flow into the burner assembly includes directing the exhaust flow
in a first direction, which is substantially perpendicular to a
second direction in which the heated exhaust flow is directed out
of the burner.
17. The method of claim 15, wherein the exposing of portions of the
exhaust flow to the flame in the first stage includes directing the
portions of the exhaust flow through holes in the combustion
chamber member and, in the subsequent stages, includes directing
the additional portions of the exhaust flow through holes in a
conical portion at locations progressively further downstream, the
conical portion having an upstream end attached to a downstream end
of the combustion chamber member and a downstream end, wider than
the upstream end of the conical portion, the totality of exhaust
flow directed through the burner assembly passing through the
conical portion.
18. The method of claim 17, further including directing at least a
portion of the exhaust flow through a baffle located within the
conical portion.
19. The method of claim 18, wherein the portion of the exhaust flow
that is directed through the baffle is directed through holes about
the periphery of the baffle.
20. The method of claim 15, further including introducing fresh air
to a fuel injector having a fuel conduit and configured to deliver
fuel to the combustion chamber, the fresh air being introduced to
the fuel injector upstream of the exhaust flow and downstream of a
location at which the fuel leaves the fuel conduit.
21. The system of claim 20, further including directing fresh air
through longitudinal, angled slots in an outer annular wall of the
fuel injector, situated about the fuel conduit thereby imparting a
rotational motion on the fresh air.
Description
TECHNICAL FIELD
[0001] The present disclosure is directed to a particulate trap
regeneration system and, more particularly, to a particulate trap
regeneration system having a burner assembly configured to increase
the temperature of exhaust gases directed to the particulate
trap.
BACKGROUND
[0002] Engines, including diesel engines, gasoline engines, natural
gas engines, and other engines known in the art, may exhaust a
complex mixture of air pollutants. The air pollutants may be
composed of both gaseous and solid material, such as, for example,
particulate matter. Particulate matter may include ash and unburned
carbon particles called soot.
[0003] Due to increased environmental concerns, exhaust emission
standards have become more stringent. The amount of particulates
and gaseous pollutants emitted from an engine may be regulated
depending on the type, size, and/or class of engine. In order to
meet these emissions standards, engine manufacturers have pursued
improvements in several different engine technologies, such as fuel
injection, engine management, and air induction, to name a few. In
addition, engine manufacturers have developed devices for treatment
of engine exhaust after it leaves the engine.
[0004] Engine manufacturers have employed exhaust treatment devices
called particulate traps to remove the particulate matter from the
exhaust flow of an engine. A particulate trap may include a filter
designed to trap particulate matter. The use of the particulate
trap for extended periods of time, however, may enable particulate
matter to accumulate on the filter, thereby causing the
functionality of the filter and/or engine performance to
decline.
[0005] One method of restoring the performance of a particulate
trap may include regeneration. Regeneration of a particulate trap
filter system may be accomplished by increasing the temperature of
the filter and the trapped particulate matter above the combustion
temperature of the particulate matter, thereby burning away the
collected particulate matter and regenerating the filter system.
This increase in temperature may be effectuated by various means.
For example, some systems employ a heating element (e.g., an
electric heating element) to directly heat one or more portions of
the particulate trap (e.g., the filter material or the external
housing). Other systems have been configured to heat the exhaust
gases upstream from the particulate trap allowing the flow of the
heated gases through the particulate trap to transfer heat to the
particulate trap. For example, some systems alter one or more
engine operating parameters, such as air/fuel mixture, to produce
exhaust gases with an elevated temperature. Running an engine with
a "rich" air/fuel mixture can have such an effect on exhaust gas
temperature.
[0006] Other systems heat the exhaust gases upstream from the
particulate trap, with the use of a burner that creates a flame
within the exhaust conduit leading to the particulate trap. For
example, one such burner system is disclosed by U.S. Pat. No.
4,641,524, issued to Brighton on Mar. 24, 1987 ("the '524 patent").
The '524 patent discloses a burner system configured to increase
the temperature of exhaust gases directed to the particulate
trap.
[0007] While the system of the '524 patent may increase the overall
temperature of the particulate trap, the system of the '524 patent
does not include an exhaust outlet configured to direct the exhaust
flow out of the burner toward the particulate trap, wherein the
exhaust outlet is oriented in a different direction than an exhaust
inlet. Further, the system of the '524 patent is not configured to
impart rotational motion on fresh air introduced to a fuel injector
of the burner to promote an even distribution of the burner
flame.
[0008] The disclosed burner assembly is directed toward overcoming
one or more of the problems set forth above.
SUMMARY OF THE INVENTION
[0009] In one aspect, the present disclosure is directed toward an
exhaust treatment system. The system may include a particulate trap
configured to remove one or more types of particulate matter from
an exhaust flow, the exhaust flow including at least a portion of a
totality of exhaust gases produced by an engine. The system may
further include a burner assembly configured to increase a
temperature of gases in the exhaust flow at a location upstream
from the particulate trap. The burner assembly may include an
exhaust inlet oriented in a direction along a first axis and
configured to direct the exhaust flow into the burner assembly and
an exhaust outlet oriented in a direction along a second axis at an
angle relative to the first axis, the exhaust outlet being
configured to direct the exhaust flow out of the burner assembly
toward the particulate trap. The burner assembly may also include a
fuel injector having a longitudinal axis in substantial alignment
with the second axis. In addition, the burner assembly may include
a cylindrical combustion chamber member defining a combustion
chamber, having a longitudinal axis in substantial alignment with
the longitudinal axis of the fuel injector, and configured to house
a flame that is fueled by the fuel injector within the combustion
chamber. The burner assembly may further include an exhaust flow
distribution member configured to substantially evenly distribute
exhaust about the combustion chamber member and in a heat exchange
relation to the combustion chamber member.
[0010] In another aspect, the present disclosure is directed toward
work machine having an exhaust treatment system. The work machine
may include an exhaust gas producing engine and an exhaust conduit
for directing an exhaust flow to a particulate trap configured to
remove one or more types of particulate matter from the exhaust
flow, the exhaust flow including at least a portion of a totality
of exhaust gases produced by the engine. The system may further
include a burner assembly configured to increase a temperature of
the exhaust flow at a location upstream from the particulate trap.
The burner assembly may include an exhaust inlet configured to
direct the exhaust flow into the burner assembly and an exhaust
outlet configured to direct the exhaust flow out of the burner
assembly toward the particulate trap, the exhaust outlet being
oriented in a direction substantially perpendicular to the exhaust
inlet. The burner assembly may also include a fuel injector having
a longitudinal axis in substantial alignment with the direction in
which the exhaust outlet is oriented. In addition, the burner
assembly may include a cylindrical combustion chamber member
defining a combustion chamber, having a longitudinal axis in
substantial alignment with the longitudinal axis of the fuel
injector, and configured to house a flame that is fueled by the
fuel injector within the combustion chamber. The burner assembly
may further include an exhaust flow distribution member positioned
about the combustion chamber member and configured to substantially
evenly distribute the exhaust flow about the combustion chamber
member and in a heat exchange relation to the combustion chamber
member.
[0011] In another aspect, the present disclosure is directed toward
a method of regenerating an exhaust particulate trap. The method
may include directing an exhaust flow, produced by an engine, into
a burner assembly, the exhaust flow including at least a portion of
a totality of exhaust gases produced by an engine, the burner
assembly being located upstream from a particulate trap configured
to remove one or more types of particulate matter from the exhaust
flow. The method may further include directing the exhaust flow
through an exhaust flow distribution member and thereby
substantially evenly distributing the exhaust flow about a
combustion chamber member to remove heat from the combustion
chamber member, the heat being created by a flame within the
combustion chamber member. The method may also include heating the
exhaust flow in stages as the exhaust flow passes through the
burner assembly by exposing a portion of the exhaust flow to the
flame at a first stage and exposing additional portions of the
exhaust flow to the flame at each subsequent stage to create a
heated exhaust flow. In addition, the method may include directing
the heated exhaust flow out of the burner assembly and to the
particulate trap to thereby increase a temperature of the
particulate trap.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a diagrammatic illustration of a work machine
according to an exemplary disclosed embodiment.
[0013] FIG. 2 is a diagrammatic, cross-sectional illustration of a
burner assembly according to an exemplary disclosed embodiment.
[0014] FIG. 3 is a diagrammatic, cross-sectional illustration of a
fuel injector according to an exemplary disclosed embodiment.
[0015] FIG. 4 is a diagrammatic, cross-sectional illustration of
the fuel injector of FIG. 3 taken at a section line 4-4 in FIG.
3.
DETAILED DESCRIPTION
[0016] Reference will now be made in detail to the drawings.
Wherever possible, the same reference numbers will be used
throughout the drawings to refer to the same or like parts.
[0017] FIG. 1 illustrates a work machine 10. Work machine 10 may
include one or more traction devices 12, an engine 14, and an
exhaust treatment system 16.
[0018] Although work machine 10 is shown as a truck, work machine
10 could be any type of machine having an exhaust producing engine.
Accordingly, traction devices 12 may be any type of traction
devices, such as, for example, wheels, as shown in FIG. 1, tracks,
belts, or any combinations thereof.
[0019] Engine 14 may be any kind of engine that produces an exhaust
flow of exhaust gases. For example, engine 14 may be an internal
combustion engine, such as a gasoline engine, a diesel engine, a
natural gas engine or any other exhaust gas producing engine.
[0020] System 16 may include a particulate trap 18 and an exhaust
conduit 20 for directing all or a portion of the exhaust gases
produced by engine 14 to particulate trap 18. Particulate trap 18
may be configured to remove one or more types of particulate matter
from the exhaust gases flowing through exhaust conduit 20.
Particulate trap 18 may include an outer housing 22, which may
encase a filter material 24 (e.g., a metal mesh) for trapping
particulate matter.
[0021] System 16 may also include a burner assembly 26 configured
to increase the temperature of the exhaust gases flowing through
exhaust conduit 20 upstream from particulate trap 18. Burner
assembly 26 may be configured to maintain or restore the
performance of particulate trap 18 through thermal regeneration.
Accumulation of exhaust flow constituents in particulate trap 18
may result in a decline in engine performance and/or possible
damage to particulate trap 18 and/or other components of system 16.
Burner assembly 26 may be configured to prevent or restore any
decline in engine performance and avoid possible damage to
particulate trap 18 and/or other components of system 16. For
example, burner assembly 26 may be configured to cause at least
some of the particulates that may have accumulated in particulate
trap 18 to be burned off.
[0022] Referring now to FIG. 2, burner assembly 26 may include an
exhaust inlet 28 configured to direct the exhaust flow from engine
14 into burner assembly 26. Burner assembly 26 may also include an
exhaust outlet 30 configured to direct the exhaust flow out of
burner assembly 26 toward particulate trap 18. Exhaust outlet 30
may be oriented in a direction along an axis at an angle relative
to an axis in which exhaust inlet 28 may be oriented. For example,
exhaust outlet 30 may be oriented in a direction substantially
perpendicular to exhaust inlet 28, as shown in FIG. 2, or at any
other angle relative to exhaust inlet 28.
[0023] Burner assembly 26 may include a fuel injector 32 having a
longitudinal axis 34 in substantial alignment with the direction in
which exhaust outlet 30 is oriented. Fuel injector 32 may be
configured to deliver fuel and fresh air to burner assembly 26 to
fuel a flame. Fuel injector 32 may be housed within an air plenum
36. A fresh air supply for fuel injector 32 may be directed through
an air inlet 38 into an air chamber 40 within air plenum 36. This
air may then be directed through openings (see FIG. 3) in an outer
annular wall 42 about a fuel conduit 44, through which fuel may be
directed. Fuel injector 32 is described in greater detail below
with regard to FIG. 3.
[0024] Fuel injector 32 may be configured to deliver the fuel and
fresh air to a combustion chamber 46, defined by a cylindrical
combustion chamber member 48. Combustion chamber member 48 may
include an upstream end 50 and a downstream end 52 and may be in
substantial alignment with longitudinal axis 34 of fuel injector
32. Combustion chamber member 48 may be configured to house a flame
within combustion chamber 46 that may be fueled by fuel injector
32. Burner assembly 26 may be configured to burn such a flame on a
constant or intermittent basis. Further, burner assembly 26 may be
configured to vary the intensity, strength, duration, and/or size
of the flame. In one embodiment, burner assembly 26 may be
configured to burn a flame intermittently based on an amount of
particulates accumulated by particulate trap 18. For example,
burner assembly 26 may be configured to burn a flame based on one
or more indicators that particulate trap 18 has or may have
accumulated a predetermined amount of particulates. Such indicators
may include time of engine operation (e.g., since the last
regeneration of particulate trap 18) or other engine operating
parameters, an increase in back pressure upstream from particulate
trap 18, a pressure differential across particulate trap 18,
etc.
[0025] Burner assembly 26 may also include an ignition device, such
as a spark plug 54. Spark plug 54 may be configured to create a
spark within combustion chamber 46 to thereby ignite the mixture of
fuel and fresh air. Spark plug 54 may be fired periodically to
ignite the fuel being delivered by fuel injector 32. For example,
spark plug 54 may be fired when fuel delivery is initiated in order
to ignite the flame. Further, spark plug 54 may be fired
continually to help further stabilize the flame (e.g., keep it
burning consistently and with consistent intensity). For example,
spark plug 54 may be fired continually whenever fuel is being
delivered by fuel injector 32.
[0026] Burner assembly 26 may include an exhaust flow distribution
member 56, which may be positioned about combustion chamber member
48. For example, exhaust flow distribution member 56 may be
positioned concentrically about combustion chamber member 48.
Exhaust flow distribution member 56 may be configured to
substantially evenly distribute exhaust gases about combustion
chamber member 48 in a heat exchange relation to combustion chamber
member 48. Exhaust flow distribution member 56 may include holes 58
to facilitate this substantially even distribution of exhaust gases
about combustion chamber member 48. In addition, exhaust flow
distribution member 56 may be configured to cause the exhaust gases
to impinge on the outer surface of combustion chamber member 48,
thus, providing cooling of combustion chamber member 48. This
cooling may result from the temperature of the exhaust gases being
relatively lower than that of combustion chamber member 48, which
may be heated by the flame within combustion chamber 46. Thus, the
heat exchange relation means that the exhaust gases may draw heat
away from (i.e., cool) combustion chamber member 48.
[0027] Exhaust outlet 30 may include a conical portion 60. Conical
portion 60 may have holes 62 in it, a narrow upstream end 64
attached to downstream end 52 of combustion chamber member 48, and
a wide downstream end 66, wider than upstream end 64, and through
which all exhaust flow directed through burner assembly 26 may
pass. Exhaust outlet 30 may further include a baffle 68 located
within conical portion 60 of exhaust outlet 30 and which may be
configured to stabilize the flame that is fueled by fuel injector
32. That is, baffle 68 may stabilize the flame by creating a
partial barrier to restrain the flame from propagating too far
downstream, which could cause damage to particulate trap 18. Baffle
68 may include an unperforated central portion 70 for restraining
the central portion of the flame. Baffle 68 may also include holes
72 about its periphery for allowing limited flame propagation
beyond baffle 68. The peripheral location of holes 72 and the
resulting peripheral flame propagation may contribute to a
discharge of the exhaust gases from exhaust outlet 30 having a
substantially uniform temperature and velocity.
[0028] FIG. 3 illustrates a cross sectional view of fuel injector
32. Fuel conduit 44 may include one or more holes 74 through which
fuel may be delivered to an annular cavity 76 defined between fuel
conduit 44 and outer annular wall 42. Outer annular wall 42 may be
concentric with fuel conduit 44. Holes 74 may be configured to
atomize the fuel in preparation for combustion. Fresh air may be
drawn into annular cavity 76 through openings in outer annular wall
42, such as holes 78 and/or longitudinal slots 80. Thus, burner
assembly 26 may be configured to introduce fresh air to fuel
injector 32 upstream of the exhaust flow and downstream of a
location at which fuel leaves fuel conduit 44.
[0029] FIG. 4 is a cross-sectional illustration of fuel injector 32
taken at section line 4-4 in FIG. 3. As shown in FIG. 4,
longitudinal slots 80 may be angled so as to impart a rotational
("swirling") motion on the fresh air within the annular cavity.
Such rotational motion of the fresh air may also create swirling
motion of the atomized fuel being dispensed into annular cavity 76
from fuel conduit 44. The swirling motion of the air/fuel mixture
may contribute to a uniform distribution of fuel, as well as
uniformity in the size of fuel droplets.
INDUSTRIAL APPLICABILITY
[0030] The disclosed burner assembly 26 may be suitable to enhance
exhaust emissions control for engines. Burner assembly 26 may be
used for any application of an engine. Such applications may
include, for example, stationary equipment such as power generation
sets, or mobile equipment, such as vehicles. The disclosed system
may be used for any kind of vehicle, such as, for example,
automobiles, work machines (including those for on-road, as well as
off-road use), and other heavy equipment.
[0031] Burner assembly 26 may be configured to raise the
temperature of exhaust gases flowing through it without undesirably
restricting the flow of such gases. With minimal flow restriction,
burner assembly 26 may avoid creating backpressure within exhaust
conduit 20 that could inhibit engine performance. Further, burner
assembly 26 may be configured to generate an output flow of exhaust
gases at exhaust outlet 30 with a substantially uniform temperature
and velocity.
[0032] Burner assembly 26 may be configured to raise the
temperature of exhaust gases flowing through it by exposing them to
a fueled flame. The exhaust gases may be mixed with the flame in
stages, as the exhaust gases and flame proceed downstream to
prevent the rapidly flowing exhaust gases from extinguishing the
flame. The flame may burn within combustion chamber 46 defined by
combustion chamber member 48 and may propagate downstream into
conical portion 60 of exhaust outlet 30. A small portion of the
exhaust gases may be allowed to enter combustion chamber 46 to
supply additional oxygen to the flame to burn off any remaining
fuel not burned off using the fresh air supplied. This additional
oxygen may enable the flame to propagate further downstream.
[0033] More of the exhaust gases may be allowed to enter conical
portion 60 upstream of baffle 68 and may also supply additional
oxygen to the flame, while being heated by it. The flame within
conical portion 60 upstream of baffle 68 may propagate through
holes 72 of baffle 68 creating a wake on the downstream side of
unperforated central portion 70. Gases within this wake may have a
low flow rate, which may provide for a flame that does little
propagating downstream from that point. The remainder of the
exhaust gases may be allowed to enter conical portion 60 downstream
of baffle 68. This remainder of gases may include most of the
exhaust gases directed through exhaust inlet 28. This remainder of
gases may be heated by the flame within conical portion 60
downstream of baffle 68. Hole patterns in conical portion 60 may
contribute to the exhaust gases exiting from exhaust outlet 30 with
a substantially uniform temperature and velocity.
[0034] By introducing fresh air to fuel injector 32 and swirling
the fresh air, a stronger, more consistent, more stable, and more
evenly distributed flame may be generated than if the exhaust gases
were provided as the only source of oxygen to the flame and/or if
no swirling were generated. Additionally, because exhaust inlet 28
may be oriented in a direction perpendicular to combustion chamber
member 48, exhaust inlet 28 may direct the exhaust gases toward
combustion chamber member 48 to provide significant cooling of
combustion chamber member 48. Holes 58 in combustion chamber member
48 may facilitate even distribution of the exhaust gases about
combustion chamber member 48, which may promote cooling
efficiency.
[0035] It will be apparent to those having ordinary skill in the
art that various modifications and variations can be made to the
disclosed burner assembly for particulate trap regeneration without
departing from the scope of the invention. Other embodiments of the
invention will be apparent to those having ordinary skill in the
art from consideration of the specification and practice of the
invention disclosed herein. It is intended that the specification
and examples be considered as exemplary only, with a true scope of
the invention being indicated by the following claims and their
equivalents.
* * * * *