CN111237032A - Non-uniform thermal expansion coefficient distribution of particle traps - Google Patents
Non-uniform thermal expansion coefficient distribution of particle traps Download PDFInfo
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- CN111237032A CN111237032A CN202010046030.1A CN202010046030A CN111237032A CN 111237032 A CN111237032 A CN 111237032A CN 202010046030 A CN202010046030 A CN 202010046030A CN 111237032 A CN111237032 A CN 111237032A
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- thermal expansion
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
- F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
- F01N3/022—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters characterised by specially adapted filtering structure, e.g. honeycomb, mesh or fibrous
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
- F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
- F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Filtering Materials (AREA)
Abstract
The invention discloses a non-uniform thermal expansion coefficient distribution of a particle catcher, which comprises the following steps: s1, dividing the product into a center area and a peripheral edge area; s2, the radius of the central area is R1Product radius of R0，R1/R0The ratio is between 0 and 0.5, preferably in the range of 0.1-0.4, and the peripheral edge regions are all outside the central region; s3, the radius of the peripheral edge region is R2,R2/R0A ratio of 0.5 to 1, preferably 0.6-1, and S4, a central region having a coefficient of thermal expansion of α1At regeneration temperature T1The thermal expansion coefficient of the edge area is α2At regeneration temperature T2S5, thermal expansion coefficient of central region α1Coefficient of thermal expansion α less than edge region2At the time of regeneration, T1>>T2Central expansion value Δ L1＝α1*(T1‑TRT) Edge swell value Δ L2＝α2*(T2‑TRT) According to the calculation formula, the difference between the thermal expansion values of the center and the edge becomes smaller, thereby reducing the thermal stress.
Description
Technical Field
The invention relates to the technical field of particle traps, in particular to non-uniform thermal expansion coefficient distribution of the particle traps.
Background
The honeycomb ceramic particle trap technology has been widely used in the treatment of automobile and truck exhaust, and generally, the honeycomb ceramic particle trap employs wall-flow filtration to remove particles in the exhaust. The principle is that at the inlet every other hole is blocked, the other hole remains open, while at the outlet the corresponding hole remains blocked or open in the opposite direction. Therefore, the honeycomb ceramic is in a chessboard type of the chess, and ensures that tail gas must pass through the wall, thereby achieving the purpose of retaining particles in the tail gas on the wall.
In application, particles (such as carbon black) in the tail gas are gathered in a channel which is not blocked at the inlet, and after a certain amount of particles is obtained, a computer system starts a regeneration process to burn off the collected carbon black, so that the back pressure of the system is reduced. Since most of such carbon blacks are small particles of micron or nanometer size, they burn at a very fast rate and release a large amount of heat in a very short time (over ten minutes), which causes the temperature inside the particle trap to rise sharply, which if not well controlled, can cause the particle trap to burn and melt. By computer control of the regeneration step, the risk of melting can be reduced. However, thermal stress resulting from too high and too fast a temperature rise is always present and is a major cause of particle trap cracking.
In the temperature rising process of regeneration, the honeycomb ceramic is a large heat accumulator, so that the central temperature of the object is sharply increased, and the temperature of the edge zone is relatively low, so that a temperature gradient is formed, and thermal stress is generated. In the central zone, the body is expanded due to the relatively high temperature, while the low-temperature zones of the edges are contracted with respect to the center, resulting in the thermal stress experienced in the center being compressive stress, while the edge zones are tensile stress. In the case of ceramic bodies, the cracking is generally under tensile stress, so that the cracking caused by recycling is generally in the edge zones.
In addition, the particle trap material is typically a microcrack-type material, such as cordierite and the like. The material is characterized in that: as the temperature increases, the microcracks begin to close, causing an increase in the coefficient of thermal expansion, while the center-to-edge temperature difference increases (e.g., 1100 degrees at the center and 500 degrees at the edge) due to the temperature increase during regeneration, which is a large increase in thermal stress due to several factors.
Although there are many structural design ideas, (e.g., patent application 201910526177.8) to improve the thermal shock performance of the particle trap, all from the perspective of increasing strength, involving complex mold tooling, the present invention proposes a non-uniform thermal expansion coefficient distribution of the material inside the particle trap from the perspective of reducing thermal stress, thereby reducing thermal stress at the source, reducing the likelihood of thermal shock failure, and effectively improving the thermal shock resistance of the particle trap.
Disclosure of Invention
It is an object of the present invention to provide a non-uniform thermal expansion coefficient distribution of a particle trap to solve the problems set forth in the background art described above.
In order to achieve the purpose, the invention provides the following technical scheme: a non-uniform coefficient of thermal expansion distribution for a particle trap, comprising the steps of:
s1, dividing the product into a center area and a peripheral edge area;
s2, the radius of the central area is R1Product radius of R0，R1/R0The ratio is between 0 and 0.5, preferably in the range of 0.1-0.4, and the peripheral edge regions are all outside the central region;
s3, the radius of the peripheral edge region is R2,R2/R0The ratio is between 0.5 and 1, and the optimal range is 0.6-1;
s4, coefficient of thermal expansion of central region α1At regeneration temperature T1The thermal expansion coefficient of the edge area is α2At regeneration temperature T2；
S5, coefficient of thermal expansion α of center region1Coefficient of thermal expansion α less than edge region2At the time of regeneration, T1>>T2Central expansion value Δ L1＝α1*(T1-TRT) Edge swell value Δ L2＝α2*(T2-TRT) According to the calculation formula, the difference between the thermal expansion values of the center and the edge becomes smaller, thereby reducing the thermal stress.
Preferably, the product in S1 is a particle catcher.
Preferably, the particle trap is made of a microcracked material.
Preferably, the microcracked material has a coefficient of thermal expansion that increases with increasing temperature.
Preferably, α of the S51Is the central coefficient of thermal expansion, α2Is the coefficient of thermal expansion of the edge, T1Is the temperature of the central zone, T2Is the edge zone temperature, TRTIs at room temperature.
Compared with the prior art, the invention has the beneficial effects that:
1. the thermal expansion coefficients of the materials of the central area and the edge area are designed, so that the thermal expansion coefficient of the edge area is larger than the corresponding value of the central area.
2. Since the thermal expansion coefficient of the microcrack material increases with the temperature, the above non-uniform distribution of the thermal expansion coefficient causes a reduction in the difference between the expansion values of the center and the edge, and thus a reduction in the thermal stress, because the center temperature is significantly higher than the edge temperature during the regeneration process.
3. By such a material design, a non-uniform distribution of the thermal expansion coefficient is combined with a non-uniform distribution of the temperature, which in principle reduces the thermal stress.
4. Such material designs may also be applied with other structural designs.
Drawings
FIG. 1 is a schematic representation of the thermal expansion coefficient versus temperature for a microcracked material of the invention;
FIG. 2 is a front view of the particle trap of the present invention;
FIG. 3 is a schematic diagram of a symmetrical particle trap according to the present invention;
FIG. 4 is a schematic diagram of a particle trap with an asymmetric structure according to the present invention;
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-3, the present invention provides a technical solution: a non-uniform coefficient of thermal expansion distribution for a particle trap, comprising the steps of:
and S1, dividing the product into a central area and a peripheral edge area.
S2, the radius of the central area is R1Product radius of R0，R1/R0The ratio is between 0 and 0.5, preferably in the range of 0.1-0.4, and the peripheral edge regions are outside the central region.
S3, the radius of the peripheral edge region is R2,R2/R0The ratio is between 0.5 and 1, and the most preferred range is 0.6-1.
S4, coefficient of thermal expansion of central region α1At regeneration temperature T1The thermal expansion coefficient of the edge area is α2At regeneration temperature T2。
S5, coefficient of thermal expansion α of center region1Coefficient of thermal expansion α less than edge region2At the time of regeneration, T1>>T2Central expansion value Δ L1＝α1*(T1-TRT) Edge swell value Δ L2＝α2*(T2-TRT) According to the calculation formula, the difference between the thermal expansion values of the center and the edge becomes smaller, thereby reducing the thermal stress.
Specifically, the product in S1 is a particle trap.
In particular, the particle trap is made of a microcracked material.
In particular, the coefficient of thermal expansion of the microcracked material increases with increasing temperature.
Specifically, α in S51Is the central coefficient of thermal expansion, α2Is the coefficient of thermal expansion of the edge, T1Is the temperature of the central zone, T2Is the edge zone temperature, TRTIs at room temperature.
Example 1, referring to fig. 1-3, the particle trap is divided into two regions, a central region and an edge region, by material design, the thermal expansion coefficient of the material in the central region is lower than that in the edge region, during regeneration, the central temperature is high, the edge temperature is low, and the difference between the corresponding thermal expansion coefficients is reduced, so that the difference between the expansion amounts (from the center to the edge) is reduced, and the thermal stress is reduced, and the corresponding calculation formula is as follows:
central expansion value DeltaL1＝α1*(T1-TRT)
Edge expansion value Δ L2＝α2*(T2-TRT)
α1Is the central coefficient of thermal expansion, α2Is the coefficient of thermal expansion of the edge, T1Is the temperature of the central zone, T2Is the edge zone temperature, TRTIs at room temperature.
For the same microcracked material, the coefficient of thermal expansion increases with increasing temperature, thus leading to α1And α2Having different values, the particle trap is a cordierite particle trap, typically at the highest temperature, T, of the regeneration process1>>T2，T1Applicable temperature of 1000-1Large; and T2500-600 deg.C (near skin), α2Small, resulting in a much different amount of expansion (center expansion much greater than edge), creating tensile stress at the intersection of the center and edge, causing cracking.
Whereas in the case of the invention, the material design is such that the thermal expansion coefficient of the material in the central region is lower than that of the material in the edge region (at the same temperature), since in the regeneration case the center α is the center1(T11000-2(T2The difference becomes smaller at 500-.
The uneven distribution of the thermal expansion coefficient of the material can be achieved through special changes of materials, design and process, and the invention is not related to the material, and only provides the material design.
Example 2, referring to FIG. 4, FIG. 4 is a schematic view of the asymmetric particle trap of the present invention, the thermal expansion coefficient of the central region (α)1) Less than the coefficient of thermal expansion of the edge region (α)2) The design of the present invention is also applicable to asymmetric particle traps, where the temperature in the central region is higher than in the edge region during regeneration, resulting in reduced differential thermal expansion values and reduced thermal stresses.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (5)
1. A non-uniform thermal expansion coefficient distribution of the particle trap, characterized by: the method comprises the following steps:
s1, dividing the product into a center area and a peripheral edge area;
s2, the radius of the central area is R1Product radius of R0，R1/R0The ratio is between 0 and 0.5, preferably in the range of 0.1-0.4, and the peripheral edge regions are all outside the central region;
s3, the radius of the peripheral edge region is R2,R2/R0The ratio is between 0.5 and 1, and the optimal range is 0.6-1;
s4, coefficient of thermal expansion of central region α1At regeneration temperature T1The thermal expansion coefficient of the edge area is α2At regeneration temperature T2；
S5, coefficient of thermal expansion α of center region1Coefficient of thermal expansion α less than edge region2At the time of regeneration, T1>>T2Central expansion value Δ L1＝α1*(T1-TRT) Edge swell value Δ L2＝α2*(T2-TRT) According to the calculation formula, the difference between the thermal expansion values of the center and the edge becomes smaller, thereby reducingThe thermal stress is low.
2. The non-uniform coefficient of thermal expansion distribution of the particle trap of claim 1, wherein: the product in S1 is a particle trap.
3. The non-uniform coefficient of thermal expansion distribution of the particle trap of claim 2, wherein: the particle trap is made of a microcracked material.
4. The non-uniform coefficient of thermal expansion distribution of the particle trap of claim 3, wherein: the coefficient of thermal expansion of the microcracked material increases with increasing temperature.
5. The particle trap of claim 1, wherein α of S5 indicates a non-uniform thermal expansion coefficient distribution1Is the central coefficient of thermal expansion, α2Is the coefficient of thermal expansion of the edge, T1Is the temperature of the central zone, T2Is the edge zone temperature, TRTIs at room temperature.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010046030.1A CN111237032A (en) | 2020-01-16 | 2020-01-16 | Non-uniform thermal expansion coefficient distribution of particle traps |
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| CN202010046030.1A CN111237032A (en) | 2020-01-16 | 2020-01-16 | Non-uniform thermal expansion coefficient distribution of particle traps |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112031895A (en) * | 2020-09-16 | 2020-12-04 | 常州浩蔚环保科技有限公司 | Spliced non-uniform thermal expansion particle catcher |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102005042056A1 (en) * | 2005-09-05 | 2007-03-08 | Robert Bosch Gmbh | Filter element and soot filter with reduced temperature stresses |
| EP2915792A2 (en) * | 2014-03-04 | 2015-09-09 | NGK Insulators, Ltd. | Honeycomb structure |
| WO2017094640A1 (en) * | 2015-11-30 | 2017-06-08 | 住友化学株式会社 | Honeycomb filter intermediate, honeycomb filter, method for producing honeycomb filter intermediate, and method for producing honeycomb filter |
| CN107532490A (en) * | 2015-04-16 | 2018-01-02 | 恩必安有限公司 | Honeycomb molded body with cracking resistance |
| CN209942910U (en) * | 2019-06-10 | 2020-01-14 | 常州浩蔚环保科技有限公司 | Asymmetric chamfer structure of honeycomb ceramic particle trapper |
-
2020
- 2020-01-16 CN CN202010046030.1A patent/CN111237032A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102005042056A1 (en) * | 2005-09-05 | 2007-03-08 | Robert Bosch Gmbh | Filter element and soot filter with reduced temperature stresses |
| EP2915792A2 (en) * | 2014-03-04 | 2015-09-09 | NGK Insulators, Ltd. | Honeycomb structure |
| CN107532490A (en) * | 2015-04-16 | 2018-01-02 | 恩必安有限公司 | Honeycomb molded body with cracking resistance |
| WO2017094640A1 (en) * | 2015-11-30 | 2017-06-08 | 住友化学株式会社 | Honeycomb filter intermediate, honeycomb filter, method for producing honeycomb filter intermediate, and method for producing honeycomb filter |
| CN209942910U (en) * | 2019-06-10 | 2020-01-14 | 常州浩蔚环保科技有限公司 | Asymmetric chamfer structure of honeycomb ceramic particle trapper |
Non-Patent Citations (1)
| Title |
|---|
| 王欣等: "《建筑材料》", 31 January 2019 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112031895A (en) * | 2020-09-16 | 2020-12-04 | 常州浩蔚环保科技有限公司 | Spliced non-uniform thermal expansion particle catcher |
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Application publication date: 20200605 |