KR20130057840A

KR20130057840A - Exhaust gas processing device

Info

Publication number: KR20130057840A
Application number: KR20110123793A
Authority: KR
Inventors: 권충일
Original assignee: 현대자동차주식회사; 기아자동차주식회사
Priority date: 2011-11-24
Filing date: 2011-11-24
Publication date: 2013-06-03

Abstract

PURPOSE: An exhaust gas processing device is provided to form the thickness of a partition wall between channels differently according to a temperature gradient, thereby improving the resistance with respect to thermal stress and durability. CONSTITUTION: An exhaust gas processing device comprises a catalyst unit(100). The catalyst unit includes channels functioning as a passage for exhaust gas, and a partition wall(410) is formed between the channels. The thickness of the partition wall formed in a portion where a temperature change is rapid from the central unit(600) of a channel to an outer surface(610) thereof is formed thicker. The catalyst unit is a diesel smoke filter and formed of a cordierite material.

Description

Exhaust Gas Treatment System {EXHAUST GAS PROCESSING DEVICE}

The present invention relates to an exhaust gas treatment apparatus for collecting particulate matter contained in exhaust gas using a diesel particulate filter made of cordierite material, and removing the particulate matter contained in the exhaust gas under a set condition.

Currently, in order to cope with the exhaust gas regulation in passenger diesel engines, diesel oxidation catalyst (DOC), diesel particulate filter (DPF), nitrogen oxide purification unit (LNT, lean NOx trap), and selective reduction catalyst unit (SCR) reduction units) and the like.

The diesel particulate filter is mandatory to satisfy the regulation of particulate matter discharged from the diesel engine, the vehicle price will increase when made of SiC or AT material.

Therefore, a diesel soot filter made of relatively inexpensive cordierite material is applied, and the strength of the cordierite material is low in thermal conductivity due to its characteristics.

It is an object of the present invention to provide an exhaust gas treating apparatus which can improve the durability and protect against thermal stress of a diesel particulate filter made of cordierite material having a relatively low strength and low thermal conductivity.

As described above, in the exhaust gas treating apparatus according to the present invention, channels are formed as a passage through which exhaust gas flows from the front to the rear, and partition walls are formed between the channels, and the thickness of the partition walls in the direction of the outer surface from the center thereof. It includes a catalyst unit having a thickened portion.

The thickness of the partition wall becomes thinner from the outer surface of the catalyst unit to the depth set in the direction of the center, and the thickness thereof is constant thereafter.

A high temperature exhaust gas passes through the channels of the catalyst unit, and the thickness of the partition wall formed at a portion where the temperature change is sharp from the center portion to the outer surface direction is made thicker than the thickness of the center portion.

The catalyst unit is formed of cordierite material.

The channels include a first channel whose inlet is closed with a plug, the outlet is open, and a second channel whose inlet is open and the outlet is closed with a plug, wherein the first channel and the second channel are closed. The channels are alternately arranged adjacent to each other, and exhaust gas passes through the partition wall, and the catalyst unit is a diesel particulate filter.

According to the present invention for achieving the above object, in the diesel particulate filter made of cordierite material, by forming the partition wall thickness between the channels according to the temperature gradient, the durability and resistance to thermal stress can be improved. have.

1 is a schematic cross-sectional view of a catalyst unit having a symmetrical structure according to an embodiment of the present invention.
2 is a schematic cross-sectional view of a catalyst unit having an asymmetric structure according to an embodiment of the present invention.
3 is a graph showing a change in temperature with a distance from the center of the catalyst unit according to an embodiment of the present invention.
4 is an enlarged view of a part of the front surface of the catalyst unit according to the embodiment of the present invention.
5 is a graph showing the thickness of the partition wall according to the distance from the outer surface in the catalyst unit according to an embodiment of the present invention.
Figure 6 is a side view showing the front of the catalyst unit according to an embodiment of the present invention.
7 is a graph showing the thermal stress analysis results of the catalyst unit according to the embodiment of the present invention.
8 is a graph showing the internal temperature of the catalyst unit according to the embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic cross-sectional view of a catalyst unit having a symmetrical structure according to an embodiment of the present invention.

Referring to FIG. 1, the catalyst unit 100 includes a first channel 140a and a second channel 140b adjacent thereto, and the inlet 110 of the first channel 140a is opened and the outlet thereof. 120 is a structure closed by the plug 130. In addition, the inlet 110 of the second channel 140b is closed by the plug 130, and the outlet 120 is open.

Exhaust gas flowing into the inlet of the first channel 140a passes through the partition wall 410 between the first channel 140a and the second channel 140b and exits the outlet of the second channel 140b. 120, the shape of the inlet 110 of the first channel 140a and the shape of the outlet 120 of the second channel 140b have the same symmetrical structure.

In an embodiment of the present invention, the catalyst unit is formed of a cordierite material, it can be applied to a diesel particulate filter for collecting particulate matter contained in the exhaust gas of the diesel engine.

2 is a schematic cross-sectional view of a catalyst unit having an asymmetric structure according to an embodiment of the present invention.

Referring to FIG. 2, the catalyst unit 100 includes a first channel 140a and a second channel 140b adjacent thereto, and the inlet 110 of the first channel 140a is opened and the outlet thereof. 120 is a structure closed by the plug 130. In addition, the inlet 110 of the second channel 140b is closed by the plug 130, and the outlet 120 is open.

Exhaust gas flowing into the inlet of the first channel 140a passes through the partition wall 410 between the first channel 140a and the second channel 140b and exits the outlet of the second channel 140b. 120, the shape of the inlet 110 of the first channel 140a and the shape of the outlet 120 of the second channel 140b are not the same. That is, the diameter of the inlet 110 of the first channel 140a is large and the diameter of the outlet 120 of the second channel 140b is small.

In FIGS. 1 and 2, four channels are formed, but the number of channels is not limited thereto.

3 is a graph showing a temperature change according to the distance from the central portion 600 of the catalyst unit 100 according to the embodiment of the present invention.

Referring to FIG. 3, when exhaust gas flows through the catalyst unit 100, the temperature of the center 600 of the catalyst unit 100 is about 1050 degrees Celsius, and the point at which the distance is 100 from the center 600 is It is about 1000 degrees Celsius, and the distance of 300 from the center 600 is about 900 degrees Celsius.

As shown, the temperature is sharply lowered in the range of 400 to 500 in the central portion 600, the thermal stress is generated in the partition wall 410 of the catalytic unit 100 by a sudden temperature change.

4 is an enlarged view of a part of the front surface of the catalyst unit according to the embodiment of the present invention.

Referring to FIG. 4, a first channel 140a having an inlet opening is formed at an upper right side, and a second channel 140b having an inlet closing with a plug 130 is formed at a lower right side.

A partition wall 410 is formed between the first channel 140a and the second channel 140b, and a crack 400 is generated in the partition wall 410 by thermal stress. Therefore, due to the crack 400, the function of the catalyst unit 100 as a whole may be reduced, and durability may be shortened.

5 is a graph showing the thickness of the partition wall according to the distance from the outer surface in the catalyst unit according to an embodiment of the present invention.

Referring to FIG. 5, the horizontal axis represents the distance from the outer surface, and the vertical axis represents the thickness of the partition wall 410.

As shown, the thickness of the barrier rib 410 is constantly reduced when the distance from the outer surface 610 is 0 to 3, and from 3 the barrier rib 410 has a constant thickness.

In an embodiment of the present invention, a portion of which the thickness of the partition wall 410 is constant may be differently applied in the application step, but a portion of which the temperature change is sharp is preferably formed to be thick.

Figure 6 is a side view showing the front of the catalyst unit according to an embodiment of the present invention.

Referring to FIG. 6, the thickness of the partition wall 410 is shown from the central portion 600 of the catalyst unit 100 toward the outer surface 610.

As shown, assuming that the thickness of the partition wall 410 around the central portion 600 of the catalyst unit 100 is 100%, the thickness of the partition wall 410 of the portion 620 adjacent to the outer surface is 150%, and the inner side thereof. The thickness of the partition wall 410 of 630 may be set to 120%.

As described above, by forming the thickness of the partition 410 differently according to the temperature gradient, cracks are prevented from occurring due to thermal stress.

7 is a graph showing the thermal stress analysis results of the catalyst unit according to the embodiment of the present invention.

Referring to Figure 7, the horizontal axis represents the existing catalyst unit and the catalyst unit 100 of the present invention, the vertical axis represents the thermal stress.

As shown, assuming that the thermal stress of the existing catalyst unit is 100%, the thermal stress generated in the catalyst unit 100 of the present invention is reduced to about 80%. That is, the thickness of the partition 410 is thick, there is an effect that the thermal stress is injected.

8 is a graph showing the internal temperature of the catalyst unit according to the embodiment of the present invention.

Referring to FIG. 8, the horizontal axis represents the amount of particulate matter collected in the catalyst unit 100, and the vertical axis represents the internal temperature of the catalyst unit 100.

As shown, when the particulate matter is the same, the internal temperature of the catalyst unit 100 of the present invention is relatively lower than that of the conventional catalyst unit, and the cracks are not generated in the partition wall 410 as experimental data. Can be.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, And all changes to the scope that are deemed to be valid.

100: catalytic unit
110: entrance
120: exit
130: plug
140a: first channel
140b: second channel
400: crack
410: bulkhead
600: center
610: outer side

Claims

Channels are formed as a passage through which exhaust gas flows from the front to the rear, and partition walls are formed between the channels.
A catalyst unit having a portion in which the thickness of the partition becomes thicker from the center to the outer surface direction; Exhaust gas treatment apparatus comprising a.

In claim 1,
And the thickness of the partition wall becomes thinner from the outer surface of the catalyst unit to the depth set in the direction of the center portion, after which the thickness is constant.

In claim 1,
A high temperature exhaust gas passes through the channels of the catalyst unit, and the thickness of the partition wall formed at a portion where the temperature change is sharp from the center to the outer surface is formed thicker than the thickness of the center portion. Gas processing unit.

In claim 1,
The catalyst unit is an exhaust gas treatment device, characterized in that formed of cordierite material.

5. The method of claim 4,
The channels,
A first channel whose inlet is closed with a plug and whose outlet is open; And
The inlet is open and the outlet comprises a second channel closed by a plug,
And the first channel and the second channel are alternately disposed adjacent to each other, and exhaust gas passes through the partition wall, and the catalyst unit is a diesel particulate filter.