JP6826969B2 - Heat exchanger - Google Patents

Description

The present invention relates to a heat exchanger.

As shown in FIG. 14, the heat exchanger 40 of Patent Document 1 is divided into a rectangular tubular peripheral wall 41 and a plurality of first cells 42 and second cells 43 extending in the axial direction of the peripheral wall 41 inside the peripheral wall 41. It is provided with a partition wall 44 to be used. In the cross section orthogonal to the axial direction of the peripheral wall 41, the first cell 42 and the second cell 43 are arranged so as to form a row in the vertical direction, respectively. Specifically, the first cell 42 is arranged in the first row, the third row, the fifth row, and the seventh row from the left side of the paper in FIG. 14, and the second row, the fourth row, the sixth row, and the eighth row. The second cell 43 is arranged in. In such a heat exchanger 40, heat exchange is performed between the first fluid flowing through the first cell 42 and the second fluid flowing through the second cell 43.

Further, in the heat exchanger 40 of Patent Document 1, the flow path cross-sectional area of the second cell 43 is made larger than the flow path cross-sectional area of the first cell 42. Then, when heat exchange is performed between fluids having different heat capacities, a second fluid having a smaller heat capacity is flowed to the second cell 43 side having a large flow path cross-sectional area, and more second fluids are flown in the heat exchanger 40. Is present so that the heat capacity of the entire first fluid and the heat capacity of the entire second fluid in the heat exchanger 40 are combined to improve the heat exchange efficiency.

JP-A-2015-140960

By the way, a heat exchanger as shown in FIG. 14 may be used for heat exchange between a gas such as exhaust gas and a liquid heat medium such as cooling water. In this case, the heat of the gas is transferred to the liquid heat medium through the partition wall of the heat exchanger, but the heat of the gas is difficult to be transferred to the partition wall, so that the heat exchange efficiency of the heat exchanger is improved. There was a problem that it was difficult. The present invention has been made in view of these circumstances, and an object of the present invention is to provide a heat exchanger having high heat exchange efficiency.

The heat exchanger of the present invention for solving the above problems has a tubular peripheral wall and a partition wall that divides the inside of the peripheral wall into a plurality of heat medium flow cells extending in the axial direction of the peripheral wall and a plurality of gas flow cells. A heat exchanger in which heat exchange is performed between a liquid heat medium that circulates in the heat medium distribution cell and a gas that circulates in the gas flow cell. The gist is that the number ratio with the gas flow cell is 1: 3 to 1: 6.

According to this configuration, since the number of gas flow cells is three times or more the number of heat medium flow cells, the total flow path cross-sectional area of the gas flow cells becomes large, and the gas passing through the gas flow cells The flow velocity of As a result, the contact time between the gas and the partition wall becomes long. Further, since the contact area between the gas and the partition wall is also large, the heat of the gas is easily transferred to the partition wall. Further, since the number of gas distribution cells is 6 times or less with respect to the number of heat medium distribution cells, the entire partition wall can be cooled by the liquid heat medium flowing through the heat medium distribution cells. By cooling the entire partition wall, the heat of the gas can be transferred quickly. As a result, the heat exchange efficiency of the heat exchanger can be improved.

In the heat exchanger of the present invention, the peripheral wall has a rectangular tubular shape having a pair of facing first side walls and a pair of facing second side walls, and the heat medium flow cell and the gas flow cell have the peripheral wall. A plurality of heat medium flow cell rows and a plurality of gas flow cell rows arranged in parallel with the first side wall are provided in a cross section orthogonal to the axial direction of the above, and the heat media adjacent to each other in the direction along the second side wall. It is preferable that the gas distribution cell rows of 3 to 6 are arranged between the distribution cell rows. According to this configuration, the entire partition wall is cooled by arranging the heat medium flow cells in a solid state and by arranging the heat medium flow cells within a certain range for most of the gas flow cells. And the pressure loss can be reduced.

In the heat exchanger of the present invention, it is preferable that the inlet and outlet of the heat medium communicating with the heat medium flow cell are provided on the same surface of the peripheral wall. According to this configuration, by providing the inflow port and the outflow port of the heat medium on one side of the heat exchanger, the total volume when the pipe or the like through which the heat medium flows is connected can be reduced.

Regarding the heat exchanger of the present invention, it is preferable that the plurality of heat medium flow cells each have the same cross-sectional shape, and the plurality of gas flow cells each have the same cross-sectional shape. According to this configuration, it is possible to suppress variations in heat exchange efficiency between gas flow cells and heat exchange efficiency between heat medium flow cells caused by different cross-sectional shapes, and it is possible to suppress pressure loss in gas flow cells. Can be reduced.

Regarding the heat exchanger of the present invention, it is preferable that each of the heat medium flow cells has a larger cross-sectional shape than each of the gas flow cells in a cross section orthogonal to the axial direction of the peripheral wall. Heat medium distribution Since the heat medium that circulates in the cell is liquid, the distribution resistance when circulating the cell is larger than that in gas. According to this configuration, it is possible to facilitate the distribution of a heat medium having a high distribution resistance.

Regarding the heat exchanger of the present invention, it is preferable that the partition wall contains silicon carbide as a main component. According to this configuration, since silicon carbide is a material having a high thermal conductivity among ceramic materials, the thermal conductivity of the partition wall can be increased. As a result, the heat exchange efficiency of the heat exchanger can be improved.

According to the present invention, the heat exchange efficiency can be improved.

Perspective view of the heat exchanger. 2-2 sectional view of FIG. FIG. 2 is a sectional view taken along line 3-3 of FIG. FIG. 2 is a sectional view taken along line 4-4 of FIG. Explanatory drawing of molding process. Explanatory drawing of the processing process (explanatory drawing of the state in which the processing jig of the first processing is inserted). Explanatory drawing of the processing process (explanatory drawing after inserting the processing jig of the first processing). Explanatory drawing of processing process (explanatory drawing of 2nd processing). Explanatory drawing of degreasing process. Explanatory drawing of impregnation process. Front view of the heat exchanger of the modified example. The schematic diagram which shows the dimensional measurement point in a simulation. Simulation temperature distribution map. Sectional view of the prior art heat exchanger.

Hereinafter, an embodiment of the heat exchanger will be described.
As shown in FIGS. 1 and 2, the heat exchanger 10 of the present embodiment has a rectangular tubular peripheral wall 11, a plurality of heat medium flow cells 13a extending inside the peripheral wall 11 in the axial direction of the peripheral wall 11, and a plurality of gases. It is provided with a partition wall 12 for partitioning the distribution cell 13b. The rectangular tubular peripheral wall 11 has a pair of vertical side walls 11a (first side wall) facing each other and a pair of lateral side walls 11b (second side wall) facing each other, and the cross-sectional shape orthogonal to the axial direction of the peripheral wall 11 is horizontally long. It is configured to form a rectangle.

As shown in FIG. 2, the partition wall 12 has a cross section orthogonal to the axial direction of the peripheral wall 11 so that the partition wall 12 parallel to the vertical side wall 11a and the partition wall 12 parallel to the horizontal side wall 11b form a grid pattern. It is configured in. The cell structure formed by the partition wall 12 is not particularly limited. For example, a cross section in which the wall thickness of the partition wall 12 is 0.1 to 0.5 mm and the cell density is orthogonal to the axial direction of the peripheral wall 11. It can have a cell structure of 15 to 93 cells per 1 cm ² .

As shown in FIG. 3, the heat medium distribution cell 13a is a cell for distributing a heat medium, and both ends thereof are sealed by a sealing portion 22. As shown in FIG. 4, the gas distribution cell 13b is a cell for distributing the gas to be processed, and both ends thereof are open. The heat medium is not particularly limited, and a known liquid heat medium can be used. Known heat media include, for example, cooling water (Long Life Coolant: LLC) and an organic solvent such as ethylene glycol. Examples of the gas to be processed include the exhaust gas of an internal combustion engine.

As shown in FIG. 2, in the cross section orthogonal to the axial direction of the peripheral wall 11, the cross-sectional shape of the heat medium flow cell 13a and the cross-sectional shape of the gas flow cell 13b are all the same.
As shown in FIG. 2, the heat exchanger 10 includes a plurality of heat medium flow cell rows 14a in which only the heat medium flow cell 13a is arranged parallel to the vertical side wall 11a of the peripheral wall 11, and a gas flow cell parallel to the vertical side wall 11a. It includes a gas distribution cell row 14b in which only 13b is arranged.

Here, in the heat exchanger 10, the number ratio of the heat medium flow cell 13a and the gas flow cell 13b is set in a specific range. The number ratio (heat medium distribution cell 13a: gas distribution cell 13b) is 1: 3 to 1: 6, and preferably 1: 4 to 1: 5.

In the present embodiment, the number ratio is adjusted by arranging the heat medium flow cell row 14a and the gas flow cell row 14b. That is, in the direction along the lateral side wall 11b of the peripheral wall 11, a plurality of rows of gas flow cell rows 14b are arranged between adjacent heat medium flow cell rows 14a, and an arrangement pattern in which this arrangement is repeated is formed. ing. Then, by setting the number of gas distribution cell rows 14b arranged between the two adjacent heat medium distribution cell rows 14a to 3 to 6 rows, the number ratio becomes 1: 3 to 1: 6. Further, the number of gas distribution cell rows 14b is preferably 4 to 5 rows.

As shown in FIGS. 1 and 3, in the heat exchanger 10, the heat medium flow cell row 14a is formed so as to extend in the vertical direction and penetrates the partition wall 12 that partitions the adjacent heat medium flow cells 13a. Therefore, a communication unit 15 for communicating each cell constituting the heat medium distribution cell row 14a is provided. The end of the communication portion 15 on one side (upper side in FIG. 3) in the vertical direction opens to the peripheral wall 11 (horizontal side wall 11b), and the end on the other side (lower side in FIG. 3) is in the vertical direction. It reaches the heat medium distribution cell 13a located on the farthest side. The heat exchanger 10 has, as the communication portion 15, the first communication portion 15a provided on the side of the first end portion 10a, which is one end in the axial direction of the heat exchanger 10, and the heat exchanger 10 in the axial direction. It has a second communication portion 15b provided on the second end portion 10b side, which is the other end portion.

As shown in FIG. 3, the inside of the heat exchanger 10 is composed of a heat medium flow cell 13a, a first communication portion 15a, and a second communication portion 15b, and is formed on the peripheral wall 11 of the heat exchanger 10. A heat medium flow path 16 is formed in which each opening of the first communication portion 15a and the second communication portion 15b is used as an inlet or an outlet. Further, as shown in FIG. 4, a gas flow path 17 is formed inside the heat exchanger 10 and is composed of gas flow cells 13b and has both ends 10a and 10b in the axial direction as inlets or outlets. .. The heat exchanger 10 having the above configuration can exchange heat between the heat medium flowing through the heat medium flow path 16 and the gas flowing through the gas flow path 17 via the partition wall 12.

The material constituting the rectangular tubular peripheral wall 11 of the heat exchanger 10 and the partition wall 12 is not particularly limited, and materials used in known heat exchangers can be used, for example, silicon carbide. Examples thereof include carbides such as tantalum carbide and tungsten carbide, and nitrides such as silicon nitride and boron nitride. Among these, a material containing silicon carbide as a main component is preferable because it has a higher thermal conductivity than other ceramic materials and can increase the heat exchange efficiency. Here, the "main component" is assumed to mean 50% by mass or more. Examples of the material containing silicon carbide as a main component include materials containing silicon carbide particles and metallic silicon.

Next, one manufacturing method of the heat exchanger of the present embodiment will be described with reference to FIGS. 5 to 10. The heat exchanger is manufactured by going through the molding step, the processing step, the degreasing step, and the impregnation step described below in this order.

(Molding process)
A clay-like mixture containing silicon carbide particles, an organic binder, and a dispersion medium is prepared as a raw material used for molding the heat exchanger. As shown in FIG. 5, this clay-like mixture is used to form a rectangular tubular peripheral wall 11 and a partition wall 12 for partitioning the inside of the peripheral wall 11 into a plurality of cells 13 extending in the axial direction of the peripheral wall 11. Mold the body 20. Both ends of the molded body 20 are open for all cells 13. The molded body 20 can be molded by, for example, extrusion molding. The obtained molded product 20 is subjected to a drying treatment for drying the molded product 20.

(Processing process)
In the processing step, the first processing for forming the first communication portion and the second communication portion in the molded body and the second processing for sealing both ends of some cells in the molded body are performed.

As shown in FIG. 6, in the first processing, for example, by using a method of bringing the heated processing tool 21 into contact with the molded body, a part of the peripheral wall 11 and the partition wall 12 in the molded body 20 is removed, and the first processing is performed. The first communication portion 15a and the second communication portion 15b are formed.

Specifically, as shown in FIG. 6, as the processing tool 21, a blade having an outer shape corresponding to the first communication portion 15a and the second communication portion 15b is prepared. The blade is made of a heat-resistant metal (for example, stainless steel), and its thickness is set so as not to exceed the width of the heat medium flow cell 13a. Next, the blade is heated so that the temperature at which the organic binder contained in the molded product 20 is burned out is reached. For example, when the organic binder is methyl cellulose, the blade is heated to 400 ° C. or higher.

As shown in FIG. 7, the heated blade is inserted into the molded body 20 from the outside in the circumferential direction and then pulled out to form the first communication portion 15a and the second communication portion 15b. At this time, when the heated blade comes into contact with the molded body 20, the organic binder contained in the molded body 20 burns and burns out at the contact portion. Therefore, the insertion resistance of the blade to the molded body 20 is very small, and when the blade is inserted, the peripheral portion of the inserted portion is unlikely to be deformed or broken. In addition, the amount of processing waste generated is reduced by burning the organic binder.

As shown in FIG. 8, in the second processing, of the plurality of cells 13 formed on the molded body 20, both ends of the cells 13 constituting the heat medium flow cell 13a are clay-like used in the molding step. The mixture of the above is filled to form a sealing portion 22 that seals both ends of the cell 13. After that, the molded body 20 is subjected to a drying treatment for drying the sealing portion 22.

A processed molded product can be obtained by undergoing the above-mentioned processing steps including the first processing and the second processing. The order of the first processing and the second processing is not particularly limited, and the first processing may be performed after the second processing.

(Degreasing process)
The degreasing step is a step of obtaining a degreased body from which the organic binder has been removed from the processed molded product by burning the organic binder contained in the processed molded product by heating the processed molded product. As shown in FIG. 9, by going through the degreasing step, the organic binder is removed from the processed molded body, and a degreasing body 30 having a skeleton portion arranged in a state where the silicon carbide particles are in contact with each other is obtained.

(Immersion process)
The impregnation step is a step of impregnating the inside of each wall of the degreased body with metallic silicon. In the impregnation step, the metal silicon lumps are brought into contact with the degreased body and heated to a temperature equal to or higher than the melting point of the metallic silicon (for example, 1450 ° C. or higher). As a result, as shown in FIG. 10, the molten metallic silicon enters the gaps between the particles constituting the skeleton portion of the degreased body by the capillary phenomenon, and the metallic silicon is impregnated in the gaps.

The heat treatment of the impregnation step may be performed continuously from the heat treatment of the degreasing step. For example, in a state where a mass of metallic silicon is in contact with a processed molded body, the organic binder is removed by heating at a temperature lower than the melting point of metallic silicon to form a degreased body, and then the heating temperature is set to the melting point of metallic silicon. It is raised above and the degreased body is impregnated with the molten metallic silicon.

A heat exchanger can be obtained by going through the above impregnation step.
Here, in the present embodiment, special temperature control is performed in the steps after the degreasing step. That is, in the steps after the degreasing step, the process is carried out at a temperature lower than the sintering temperature of silicon carbide contained in the mixture used in the molding step, and the processed molded body and the degreased body are kept at a temperature equal to or higher than the above sintering temperature. I try not to expose it. Therefore, in the degreasing step, heating is performed at a temperature equal to or higher than the temperature at which the organic binder can be burnt and lower than the above sintering temperature. Similarly, in the impregnation step, heating is performed at a temperature equal to or higher than the melting point of metallic silicon and lower than the above sintering temperature.

Next, the operation and effect of this embodiment will be described.
(1) The number ratio of the heat medium distribution cell to the gas distribution cell is 1: 3 to 1: 6. When the number of gas distribution cells is three times or more the number of heat medium distribution cells, the total flow path cross-sectional area of the gas distribution cells becomes large, and the flow velocity of the gas passing through the gas distribution cells decreases. As a result, the contact time between the gas and the partition wall becomes long. Further, since the contact area between the gas and the partition wall is also large, the heat of the gas is easily transferred to the partition wall. Further, since the number of gas distribution cells is 6 times or less with respect to the number of heat medium distribution cells, the entire partition wall can be cooled by the liquid heat medium flowing through the heat medium distribution cells. By cooling the entire partition wall, the heat of the gas can be transferred quickly. As a result, the heat exchange efficiency of the heat exchanger can be improved.

(2) Three to six rows of gas distribution cells are arranged between adjacent rows of heat medium distribution cells. By arranging the heat medium flow cells in a solid state and arranging the heat medium flow cells within a certain range for most gas flow cells, the entire partition wall tends to be in a cooled state, and the pressure The loss can be reduced.

(3) On the same surface of the peripheral wall, an inlet and an outlet of the heat medium communicating with the heat medium distribution cell are provided. By providing the inflow port and the outflow port of the heat medium on one side of the heat exchanger, the total volume when the pipe or the like through which the heat medium flows is connected can be reduced.

(4) In a cross section orthogonal to the axial direction of the peripheral wall, the plurality of heat medium flow cells each have the same cross-sectional shape, and the plurality of gas flow cells each have the same cross-sectional shape. Therefore, it is possible to suppress the variation in heat exchange efficiency between gas flow cells and the variation in heat exchange efficiency between heat medium flow cells caused by the difference in cross-sectional shape.

(5) The partition wall contains silicon carbide as a main component. Since silicon carbide is a material having a high thermal conductivity among ceramic materials, the thermal conductivity of the partition wall can be increased by containing silicon carbide as a main component in the partition wall. Therefore, the heat exchange efficiency of the heat exchanger can be improved.

(6) The heat exchanger of the present embodiment is manufactured under the temperature control as described above, so that the silicon carbide particles are arranged in contact with each other to form a skeleton portion, and a gap in the skeleton portion is formed. Is filled with metallic silicon to maintain its shape. That is, the silicon carbide particles do not have a bonded portion (neck) due to sintering. This makes it possible to prevent cracks in the neck between the silicon carbide particles even if strain occurs inside the partition wall due to the internal temperature difference during use of the heat exchanger. In addition, it is possible to prevent the crack from extending through the neck.

This embodiment can also be modified and implemented as follows. It is also possible to appropriately combine the configurations of the above-described embodiment and the configurations shown in the following modified examples.
-In the present embodiment, a plurality of cell rows are arranged in the vertical direction of the rectangular tubular peripheral wall, but the cell arrangement is not limited to the vertical direction. The heat exchanger may be used sideways and the cell arrangement may be sideways.

The heat medium distribution cell row is not limited to the mode in which only the heat medium distribution cells are arranged, and may be a mode in which 80% or more of the cells are composed of the heat medium distribution cells. Further, the gas distribution cell row is not limited to the mode in which only the gas distribution cells are arranged, and may be a mode in which 80% or more of the cells are composed of gas distribution cells. That is, the heat medium distribution cell row may include gas distribution cells at a ratio of 20% or less. Further, the gas distribution cell row may include heat medium distribution cells at a ratio of 20% or less.

-The peripheral wall is not limited to a rectangular cylinder. It may be formed in a cylindrical shape or a tubular shape having an elliptical cross section. Further, the partition wall is not limited to a grid pattern in which the partition walls intersect at about 90 °. The cross section of the cell may be configured to be a rhombus, or may be configured to be a polygon other than a quadrangle. For example, the partition wall may be configured to have a hexagonal cross section. When the peripheral wall is not rectangular or cylindrical, or when the partition walls are not in a grid pattern intersecting at about 90 °, the shape of the cell formed by the peripheral wall and the partition wall may be different from the shape of other cells. For example, in the embodiment in which the partition wall has a cell having a hexagonal cross section or the like, the shape of the cell formed by the peripheral wall and the partition wall may be formed into a pentagonal cross section, a quadrangular cross section, or the like.

-The heat medium distribution cells may have different cross-sectional shapes. Further, the gas distribution cells may have different cross-sectional shapes.
-In the present embodiment, the peripheral wall and the partition wall are made of a material containing silicon carbide as a main component, but the present invention is not limited to this embodiment. Only the partition wall may be composed of a material containing silicon carbide as a main component, and the peripheral wall and the partition wall may be composed of a material other than the material containing silicon carbide as a main component.

-The size of the cross-sectional shape of the heat medium flow cell and the gas flow cell may be different in the cross section orthogonal to the axial direction of the peripheral wall. For example, as shown in FIG. 11, the heat medium flow cell 13a may be configured to have a larger dimension in the width direction and a larger cross-sectional shape than the gas flow cell 13b. The liquid heat medium that circulates in the heat medium distribution cell has a larger distribution resistance when the cell is circulated than the gas. Therefore, each heat medium distribution cell has a larger cross-sectional shape than each gas distribution cell, so that the heat medium can be easily distributed. For example, in the embodiment shown in FIG. 11, the dimensions in the width direction can be 1.0 to 5.0 mm in the heat medium flow cell and 0.9 to 2.5 mm in the gas flow cell. Further, the heat medium distribution cell may be configured to have a smaller width direction than the gas distribution cell.

-In the embodiment in which 3 to 6 rows of gas flow cell rows are arranged between adjacent heat medium cell rows, the number of gas flow cell rows does not have to be constant between 3 to 6 rows. .. That is, the number of gas flow cell rows may vary between 3 and 6 rows.

-If the number ratio of the heat medium distribution cell to the gas distribution cell is 1: 3 to 1: 6, the arrangement of the heat medium distribution cell and the gas distribution cell is such that between adjacent heat medium cell rows. The mode is not limited to the mode in which the gas flow cell rows of 3 to 6 rows are arranged. The number ratio with the gas distribution cell is 1: 3 to 1: 6, for example, when looking at an arbitrary set of 4 × 7 cells in the vertical and horizontal directions, the number of heat medium distribution cells is 4 to 4. It is 7.

Hereinafter, an example in which the above embodiment is further embodied will be described.
(Example 1)
First, a mixture having the following composition was prepared.

Silicon carbide particles with an average particle diameter of 15 μm (large particles): 52.5 parts by mass Silicon carbide particles with an average particle size of 0.5 μm (small particles): 23.6 parts by mass Methyl cellulose (organic binder): 5.4 parts by mass Parts Glycerin (lubricating agent): 1.1 parts by mass Polyoxyalkylene compound (plasticizer): 3.2 parts by mass Water (dispersion medium): 11.5 parts by mass Using this mixture, length 50 mm, width 100 mm, A molded body having a honeycomb structure having a length of 100 mm, a peripheral wall thickness of 0.3 mm, a partition wall thickness of 0.25 mm, and a cell width of 1.2 mm was molded.

Next, a plate-shaped jig heated to 400 ° C. was inserted into the peripheral wall of the molded body to form the first communication portion and the second communication portion. Further, a clay-like mixture having the same composition as the above mixture was used to seal a predetermined cell, and a processed molded product having four rows of gas flow cells was prepared between adjacent heat medium flow cells. .. That is, in the processed molded product, the number ratio of the heat medium distribution cell and the gas distribution cell was 1: 4. Next, the processed molded product was heated at 450 ° C. for 5 hours to obtain a degreased product from which the organic binder had been removed. Then, 20 g of the metal silicon plate was placed on the degreased body, and the heat exchanger was impregnated with the metal silicon by heating at 1550 ° C. for 7 hours under vacuum to obtain the heat exchanger of Example 1. ..

(Evaluation test)
For the heat exchanger of Example 1, the temperature distributions of the heat medium flow cell and the gas flow cell were evaluated by simulation. Further, as Examples 2 to 4, the gas distribution cell rows between the adjacent heat medium distribution cell rows are set to 3, 5, and 6, that is, the number ratio of the heat medium distribution cells and the gas distribution cells is set. , 1: 3, 1: 5, 1: 6, and the temperature distribution was evaluated under the same conditions as in Example 1 except for the above. Further, as Comparative Examples 1 and 2, the gas distribution cell rows between the adjacent heat medium distribution cell rows are set to 2 and 8 rows, that is, the number ratio of the heat medium distribution cell and the gas distribution cell is set to 1. The temperature distribution was evaluated under the same conditions as in Example 1 except that the values were set to 2: 2 and 1: 8.

(Simulation conditions)
The simulation conditions are shown below. The measurement points are shown in FIG. 12 for the cell dimensions.

Cell length T; 1.2 mm, cell width H; 1.2 mm, heat medium distribution cell length; 100 mm, gas distribution cell length 100 mm
-Thickness W of the partition wall; 0.25 mm, thermal conductivity of the partition wall 190 W / m · K
-The temperature of the heat medium is 40 ° C., and the flow rate of the heat medium is 10 L / min.
-Gas temperature 400 ° C, gas flow rate 10 g / sec
-Simulation software name; Fluent (registered trademark) (manufactured by Ansys)
FIG. 13 shows the result of the simulation.

The left column of FIG. 13 shows the temperature distribution diagram on the axial center side (10 mm from the axial end) of the heat exchanger, and the right column of FIG. 13 shows the outlet side (axial end) of the heat exchanger. The temperature distribution map at 90 mm) is shown. The temperature distribution in the cell is color-coded.

First, the temperature distribution of Example 1 will be described as an example. Half (1/2 cell) of the heat medium distribution cell is arranged on the left side, and two rows of gas distribution cells are arranged on the right side of the heat medium distribution cell, so that the number ratio of cells is 1: 4. Is set to. The temperature distributions of the heat medium flow cell, the partition wall, and the gas flow cell when the heat medium and the gas are circulated under predetermined conditions are shown.

As shown in FIG. 13, in each of Examples 1 to 4, the heat medium flow cell and the partition wall were at 50 ° C. or lower, and the entire partition wall was cooled. Further, on the axial center side of the heat exchanger, the maximum temperature in the gas flow cell was 120 ° C. or lower. Further, on the outlet side of the heat exchanger, the maximum temperature in the gas flow cell was 58 ° C. or lower. In particular, in Examples 1 and 3, the region where the temperature was close to 58 ° C. was small on the outlet side of the heat exchanger. From these, it was confirmed that the gas in the gas distribution cell was suitably cooled and the heat exchange efficiency was high.

On the other hand, in Comparative Examples 1 and 2, the maximum temperature in the gas flow cell was 120 ° C. or higher on the axial center side of the heat exchanger. Further, on the outlet side of the heat exchanger, the maximum temperature in the gas flow cell was 58 ° C. or higher. Further, in Comparative Example 2, on the axial center side of the heat exchanger, there was a region where the temperature of the partition wall was 50 ° C. or higher, and the entire partition wall was not cooled. From these, it was confirmed that the heat exchange efficiency was low.

10 ... heat exchanger, 11 ... peripheral wall, 12 ... partition wall, 13a ... heat medium distribution cell, 13b ... gas distribution cell.

Claims (4)

A liquid heat flowing through the heat medium flow cell is provided with a tubular peripheral wall and a partition wall that divides the inside of the peripheral wall into a plurality of heat medium flow cells extending in the axial direction of the peripheral wall and a plurality of gas flow cells. A heat exchanger in which heat is exchanged between the medium and the gas flowing through the gas distribution cell.
And the heat medium circulation cell, the number ratio of the gas flow cell is 1: 3 to 1: 6 der is,
The peripheral wall has a rectangular tubular shape having a pair of facing first side walls and a pair of facing second side walls, and the heat medium flow cell and the gas flow cell have a cross section orthogonal to the axial direction of the peripheral wall. A plurality of heat medium flow cell rows and a plurality of gas flow cell rows arranged in parallel with the first side wall are provided.
In the direction along the second side wall, 3 to 6 rows of the gas flow cell rows are arranged between the adjacent heat medium flow cell rows.
On the same surface of the peripheral wall, the heat exchanger, characterized that you have inlet and outlet of the heat medium communicated is provided in the heat medium circulating cells. The heat exchange according to claim 1, wherein in a cross section orthogonal to the axial direction of the peripheral wall, the plurality of heat medium flow cells each have the same cross-sectional shape, and the plurality of gas flow cells each have the same cross-sectional shape. vessel. The heat exchanger according to claim 1 or 2 , wherein each of the heat medium flow cells has a cross-sectional shape larger than that of the gas flow cell in a cross section orthogonal to the axial direction of the peripheral wall. The heat exchanger according to any one of claims 1 to 3 , wherein the partition wall contains silicon carbide as a main component.