US20140360161A1

US20140360161A1 - Forced air circulation for an aftertreatment module

Info

Publication number: US20140360161A1
Application number: US14/284,069
Authority: US
Inventors: Rajesh Arani; Mohamed Ibrahim Sabibullah; Venkatraman Podiyanagaswamy; Guillaume Bourgoin; Jeffery Mohamed Othman
Original assignee: Caterpillar Global Mining Expanded Products Pty Ltd
Current assignee: Caterpillar Global Mining Expanded Products Pty Ltd
Priority date: 2013-06-05
Filing date: 2014-05-21
Publication date: 2014-12-11
Also published as: IN2013DE01690A; AU2014202619A1

Abstract

A cooling system for an aftertreatment module mounted within an enclosure is provided. The cooling system includes a source of forced air in fluid communication with the enclosure. At least one duct is provided in conjunction with the source of forced air. The at least one duct is configured to direct at least a portion of the forced air from the source of forced air towards a first component of the aftertreatment module. A remaining portion of the forced air that was not directed towards to the first component is directed towards a second component of the aftertreatment module.

Description

TECHNICAL FIELD

The present disclosure relates to a cooling system, and more particularly to a system and method for cooling of an aftertreatment module located within an enclosure of a machine.

BACKGROUND

An aftertreatment module is installed on a variety of machines for meeting emission standard requirements. During operation, the aftertreatment module has a tendency to generate large amounts of heat energy. Moreover, the heat generated by the aftertreatment module may lead to an overall increase in temperature within an enclosure of the machine in which the aftertreatment module is housed. Further, some components of the aftertreatment module, such as, for example, a diesel exhaust fluid (DEF) injector and electronic circuitry associated with the aftertreatment module which are present within the enclosure may undergo further heating due to their continuous and prolonged operation. These components may need to be maintained below a specific temperature for proper functioning. Accordingly, a cooling system may be provided in association with the aftertreatment module.
Various cooling systems designs are known. For example, U.S. Published Application 2008/0142285 relates to a system for providing an airflow to an enclosure associated with a power source. The system includes a power source enclosure configured to substantially enclose a power source and a cooling package located external to the power source enclosure, including an airflow provider configured to produce an airflow through the cooling package. The system further includes an airflow redirector, configured to receive a portion of the airflow produced by the airflow provider and redirect the portion of the airflow to the power source enclosure.
In association with certain machine designs such as underground mining machines, the overall machine footprint must be kept within a certain envelope to fit the machine in narrow mine shafts. This in turn affects the relative size of the aftertreatment enclosure which is severely compact and often slightly larger than the aftertreatment module provided therein. The close proximity and high heat generated in such a confined space with little or no means to expel the heat can easily cause component failure, loss of engine performance and limited life of the engine, aftertreatment module and components in proximity thereof.

SUMMARY OF THE DISCLOSURE

In one aspect of the present disclosure, a cooling system for an aftertreatment module mounted within an enclosure is provided. The cooling system includes a source of forced air in fluid communication with the enclosure. At least one duct is provided in conjunction with the source of forced air. The at least one duct is configured to direct at least a portion of the forced air from the source of forced air towards a first component of the aftertreatment module. A remaining portion of the forced air that was not directed towards to the first component is directed towards a second component of the aftertreatment module.
In another aspect, a method for cooling an aftertreatment module mounted within an enclosure is provided. The method provides a source of forced air in fluid communication with the enclosure. The method provides at least one duct in conjunction with the source of forced air. The method directs at least a portion of the forced air from the source of forced air towards a first component of the aftertreatment module. The method directs a remaining portion of the forced air that was not directed towards to the first component, towards a second component of the aftertreatment module.
In yet another aspect, a machine is provided. The machine includes a power source and a frame. An aftertreatment module is mounted within an enclosure located on the frame. A cooling system for the aftertreatment module is provided. The cooling system includes a source of forced air in fluid communication with the enclosure. At least one duct is provided in conjunction with the source of forced air. The at least one duct is configured to direct at least a portion of the forced air from the source of forced air towards a first component of the aftertreatment module. A remaining portion of the forced air that was not directed towards to the first component is directed towards a second component of the aftertreatment module.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary machine including an aftertreatment module, according to one aspect of the present disclosure;

FIG. 2 is a perspective view of a cooling system for the aftertreatment module having a fan housing and a fan;

FIG. 3 is a cross sectional view through the center of the fan housing to illustrate a first duct and a second duct with an impeller unit partially removed;

FIG. 4 is a perspective view of a second component of the aftertreatment module; and

FIG. 5 is a flowchart of a method for cooling of the aftertreatment module.

DETAILED DESCRIPTION

Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or the like parts. FIG. 1 represents an exemplary machine 100, according to one embodiment of the present disclosure. More specifically, as shown in the illustrated embodiment, the machine 100 may embody an underground wheel loader. It should be understood that the machine 100 may alternatively include other mining, transportation, forestry or any other industrial, agricultural or construction machinery or electric power generation equipment.
Referring to FIG. 1, the machine 100 may include a chassis and/or a frame 102. A powertrain or a drivetrain (not shown) may be provided on the machine 100 for the production and transmission of motive power. The powertrain may include a power source (not shown) and may be located within an enclosure 104 of the machine 100. The power source may include one or more engines, power plants or other power delivery systems like batteries, hybrid engines, and the like. It should be noted that the power source could also be external to the machine 100. A set of ground engaging members 106, such as wheels, may also be provided on the machine 100 for the purpose of mobility. The powertrain may further include a torque converter, transmission inclusive of gearing, drive shaft and other known drive links provided between the power source and the set of ground engaging members 106 for the transmission of motive power. Further, the machine 100 may include an operator cabin 108 which may house various controls for operating the machine 100.
As shown in FIG. 1, the machine 100 may have a linkage assembly 110 attached to the frame 102. The linkage assembly 110 may include a lift arm 112. An implement, such as a bucket 114, may be pivotally coupled to the lift arm 112. It may be noted that the linkage assembly 110 and the implement of the machine 100 may vary based on the type of machine 100, the type of operation or task required to be carried out by the machine 100. Further, the machine 100 may include an air induction system (not shown) and an exhaust system (not shown). The air induction system may be configured to direct air or an air/fuel mixture into the power source for subsequent combustion.
The exhaust system may treat and discharge byproducts of the combustion process to the atmosphere as is customary. As best shown in FIG. 2, the exhaust system (not shown) may include an aftertreatment module 118 connected to receive and treat exhaust from the power source. The aftertreatment module 118 may treat, condition, and/or otherwise reduce constituents of the exhaust before the exhaust is discharged to the atmosphere.
Referring to FIG. 1, the aftertreatment module 118 (see FIG. 2) may be located within the enclosure 104 and may be provided on a side surface of the frame 102 of the machine 100. In one embodiment, a hooded structure 120 may be mounted atop the enclosure 104 or may even be integrated into a top wall of the enclosure 104. The hooded structure 120 has a raised and generally horizontally oriented top surface 121 which deflects falling dirt, debris and water away from components of the aftertreatment module 118 present beneath the hooded structure 120.
Referring now to FIG. 2, the aftertreatment module 118 may include one or more components such as, for example, a diesel oxidation catalyst (DOC) chamber, a diesel exhaust fluid (DEF) injector, a selective catalyst reduction (SCR) device and other electronic circuitry associated with aftertreatment module. During operation, there is a significant rise in temperature of the aftertreatment module 118 which may be attributed to the combustion processes taking place inside the DOC chamber. In turn the temperature increase of the aftertreatment module 118 causes an overall increase in the temperature of the environment surrounding the aftertreatment module 118, which includes sensors, electronics, and so on. These individual components of the aftertreatment module 118 may accordingly be subject to over temperature if not cooled.
The present disclosure relates to a cooling system for the aftertreatment module 118. Referring to FIG. 2 and FIG. 3, the cooling system includes a source of forced air mounted proximate to the aftertreatment module 118. The source of forced air may include a fan 202. More specifically, the fan 202 may be mounted on a fan housing 204 positioned on at least one side of the aftertreatment module 118.
The fan housing 204 may include a manifold 205 that closely overlays an impeller unit 207 of the fan 202 in order to generate significant cooling flow in the manifold 205 and direct the same towards the relatively high sources of heat within the aftertreatment module 118. The fan 202 may be mounted in proximity to a source of cool ambient air. In one embodiment, a plurality of vents or openings (not shown) may be provided on the frame 102 of the machine 100 and in close proximity to the wheels and the hooded structure 120 in order to source the cool ambient air to the fan 202 present within the hooded structure 120.
As shown, the impeller unit 207 may be mounted in a substantially vertical plane in order to force air across the aftertreatment module 118 in a generally horizontal plane. In one embodiment, a support structure in the form of a frame 206 may be provided in order to securely hold the fan 202 in position. Moreover, the impeller unit 207 of the fan 202 may be positioned in such a manner that the frame 206 is mounted onto a side wall of the enclosure 104 such that the impeller unit 207 of the fan 202 may lie outside of the enclosure 104, while the fan housing 204 may extend inwardly of the enclosure 104. The frame 206 may include a number of support arms or other structural members. The fan 202 may be configured to draw in air from the atmosphere into the fan housing 204. The fan 202 may be mechanically, hydraulically or electrically driven.
The cooling system may further include a first duct 208 and a second duct 210 provided in association with the fan 202 and within the fan housing 204. The first duct 208 may be configured to direct at least a portion of the forced air from the fan 202 towards a first component 212 of the aftertreatment module 118. The first component 212 includes electronic circuitry 214 mounted atop a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) system 216. The electronic circuitry 214 is enclosed within the hooded structure 120 and is subjected to large amounts of heat energy due to the functioning of the aftertreatment module 118 as well due to overall high temperature within the enclosure 104.
Referring to FIG. 3, the first duct 208 may be provided in the form of slots 218 within the manifold 205 of the fan housing 204. In an exemplary embodiment, the first duct 208 comprises a pair of the slots 218 formed in the manifold 205 of the fan housing 204 such that the slots 218 are in a spaced apart arrangement from each other. The slots 218 may have a substantially horizontal orientation and may be placed substantially parallel relative to each other. It should be noted that the slots 218 may be positioned and oriented relative to the location of the fan 202 and the placement of the electronic circuitry 214.
Some of the cool ambient air may be drawn in by the fan 202 and may be parasitically directed through the slots 218 towards the electronic circuitry 214 as forced by the impeller unit 207. In an exemplary embodiment, the pair of slots 218 may be configured to direct the forced air towards the electronic circuitry 214 positioned within the hooded structure 120. Arrows shown in FIG. 2 are indicative of a direction of the forced air in the system. It should be noted that the construction and design of the first duct 208 described herein is exemplary and does not limit the scope of the present disclosure. For example, the first duct 208 may additionally include a hollow tube or pipe (not shown in figures) extending from the slots 218, the tube containing perforations in order to allow forced air into and out of the tube.
The second duct 210 is generally spaced apart from the first duct 208 and may be configured to provide the remaining portion of the forced air from the fan 202 to a second component 220 of the aftertreatment module 118. The term “remaining portion of the forced air” used herein is that portion of the forced air which is not directed into the first duct 208. The second duct 210 is also housed in the manifold 205 of the fan 202, however is substantially downstream of the impeller unit 207 and the first duct 208. As a result, a relatively greater volume of the forced air from the fan 202 may be directed towards the second component 220 via the second duct 210.
The second component 220 of the aftertreatment module 118 may include a reductant injector or more specifically, a DEF injector 402 which is shown in FIG. 4. The DEF injector 402 may be subjected to large amounts of heat energy due to its own operation, heat radiating from the aftertreatment module 118 and/or overall rise in temperature within the enclosure 104. A person of ordinary skill in the art will appreciate that the DEF injector 402 may be subjected to relatively larger amounts of the heat energy as compared to the electronic circuitry 214, requiring a larger volume of the forced air for cooling purposes.
Accordingly, in one embodiment, the shape and flow passage area of the second duct 210 is sized larger than that of the slotted passage area provided by the first duct 208. Moreover, since the first duct 208 is formed within the manifold 205, the first duct 208 may receive a parasitic diversion of the forced air in the manifold 205. The first duct 208 may accommodate a relatively lesser volume of the forced air as compared to that of the second duct 210 which is located downstream of the impeller unit 207 within the fan housing 204. The volume of the forced air being directed towards the first and the second components 212, 220 may be based on the respective flow passage areas of the first and second ducts 208, 210. In one exemplary case, the flow passage area of the first and second ducts 208, 210 may be so chosen in order to direct ⅓^rdof the forced air generated by the fan 202 towards the electronic circuitry 214 and the remaining ⅔^rdof the forced air to be directed towards the DEF injector 402.
The DEF injector 402 is located at a lower section of the aftertreatment module 118. Accordingly, in the given embodiment, a tube 224 may be provided in fluid communication with the second duct 210. As shown in FIG. 2, the tube 224 has a first end 226 connected to the second duct 210 extending from the manifold 205 and a second end 404 (see FIG. 4) aimed directly at the DEF injector 402. The tube 224 extends diagonally across the DOC and DPF system 216, towards a rear portion of the aftertreatment module 118. As shown in FIG. 4, the second end 404 of the tube 224 may be positioned proximate to the DEF injector 402.
The tube 224 may be configured to direct the remaining forced air towards the DEF injector 402. Arrows shown in FIG. 2 are indicative of the direction of the forced air. In one embodiment, an insulation layer 406 may be provided on the tube 224 in order to prevent transfer of heat between the air flowing within the tube 224 and the surroundings. The insulation layer 406 may be made of any suitable heat resistant insulation material known in the art.
A method for the cooling of the aftertreatment module 118 will now be discussed in connection with FIG. 5.

INDUSTRIAL APPLICABILITY

The present disclosure relates to the cooling system for the aftertreatment module 118. FIG. 5 illustrates the method 500 for the cooling of the aftertreatment module 118. At step 502, the source of forced air may be provided in fluid communication with the enclosure 104. More specifically, the fan 202 is provided within the hooded structure 120 and in close proximity with the enclosure 104 housing the aftertreatment module 118. At step 504, at least one duct may be provided in fluid communication with the source of forced air. In one embodiment, the first duct 208 may be provided in association with the fan 202. Further, the second duct 210 may be provided in association with the fan 202.
During operation, the fan 202 may draw the forced air into the enclosure 104 to cool the aftertreatment module 118 provided therein. At step 506, at least the portion of the forced air may be directed towards the first component 212 of the aftertreatment module 118 via the first duct 208. In one embodiment, the forced air may be directed into the pair of the slots 218 provided on the fan housing 204. The forced air may be directed towards the electronic circuitry 214 positioned above the DOC and DPF system 216. The forced air may be utilized to cool the electronic circuitry 214. The forced air may then be released from the enclosure 104 through a plurality of openings 122 provided on the hooded structure 120.
At step 508, the forced air which was not directed towards the first component 212 may be directed towards the second component 220 of the aftertreatment module 118 through the second duct 210. In one embodiment, the forced air may be channelized into the tube 224 extending from the fan housing 204. The forced air may be released from the second end 404 of the tube 224 and may flow over the relatively heated DEF injector 402 positioned in close proximity to the second end 404 of the tube 224, thereby cooling the DEF injector 402.
A person of ordinary skill in the art will appreciate that although the first and second components 212, 220 of the aftertreatment module 118 described herein include the electronic circuitry 214 and the DEF injector 402 respectively, the disclosure may be utilized in the cooling of any other components of an aftertreatment system without deviating from the scope of the present disclosure. Further, the construction and design of the first and second ducts 208, 210 may vary based on the system requirements.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof

Claims

We claim:

1. A cooling system for an aftertreatment module mounted within an enclosure, the cooling system comprising:

a source of forced air in fluid communication with the enclosure; and

at least one duct provided in conjunction with the source of forced air, the at least one duct being configured to direct at least a portion of the forced air from the source of forced air towards a first component of the aftertreatment module;

wherein a remaining portion of the forced air that was not directed towards to the first component is directed towards a second component of the aftertreatment module.

2. The cooling system of claim 1, wherein the at least one duct includes a first duct and a second duct being spaced apart from each other, the second duct being provided downstream of the first duct, wherein the first duct is in fluid communication with the first component and the second duct is in fluid communication with the second component.

3. The cooling system of claim 2, wherein the first duct includes a pair of slots spaced apart from each other and in fluid communication with the source of forced air.

4. The cooling system of claim 2 further comprising a tube extending from the second duct, the tube configured to direct the remaining portion of the forced air towards the second component of the aftertreatment module.

5. The cooling system of claim 3 further comprising an insulation layer provided on the tube.

6. The cooling system of claim 2, wherein a flow passage area of the second duct is substantially greater than a flow passage area of the first duct.

7. The cooling system of claim 1 further comprising a hooded structure extending above the enclosure, wherein the source of forced air is at least partially enclosed within the hooded structure.

8. The cooling system of claim 1, wherein the first component includes electronic circuitry mounted atop the aftertreatment module.

9. The cooling system of claim 1, wherein the second component includes a reductant injector.

10. The cooling system of claim 1, wherein the source of forced air includes a fan.

11. A method for cooling an aftertreatment module mounted within an enclosure, the method comprising:

providing a source of forced air in fluid communication with the enclosure;

providing at least one duct in conjunction with the source of forced air;

directing at least a portion of the forced air from the source of forced air towards a first component of the aftertreatment module; and

directing a remaining portion of the forced air that was not directed towards to the first component towards a second component of the aftertreatment module.

12. The method of claim 11 further comprising cooling the first component and the second component of the aftertreatment module using the forced air.

13. A machine comprising:

a power source;

a frame;

an aftertreatment module mounted within an enclosure located on the frame; and

a cooling system for the aftertreatment module, the cooling system comprising:

a source of forced air in fluid communication with the enclosure; and

14. The machine of claim 13, wherein the at least one duct includes a first duct and a second duct being spaced apart from each other, the second duct being provided downstream of the first duct, wherein the first duct is in fluid communication with the first component and the second duct is in fluid communication with the second component.

15. The machine of claim 14, wherein the first duct includes a pair of slots spaced apart from each other and in fluid communication with the source of forced air.

16. The machine of claim 14 further comprising a tube extending from the second duct, the tube configured to direct the remaining portion of the forced air towards the second component of the aftertreatment module.

17. The machine of claim 14, wherein a flow passage area of the second duct is substantially greater than a flow passage area of the first duct.

18. The machine of claim 13 further comprising a hooded structure extending above the enclosure, wherein the source of forced air is at least partially enclosed within the hooded structure.

19. The machine of claim 13, wherein the first component includes electronic circuitry mounted atop the aftertreatment module.

20. The machine of claim 13, wherein the second component includes a reductant injector.