JP5759852B2 - Heat exchanger - Google Patents

Description

  The present invention relates to a heat exchanger that warms water with the heat of exhaust gas.

  In recent years, various cogeneration apparatuses have been proposed (see, for example, Patent Document 1 (FIGS. 1 and 3)).

  FIG. 1 of the patent document shows a cogeneration apparatus (10) (the numbers in parentheses indicate the symbols described in Patent Document 1. The same applies hereinafter). The generator (27) is operated by the engine (12) to obtain electric energy. Exhaust gas generated in the engine (12) is sent to the heat exchanger (14). Water is heated with the heat of the exhaust gas sent to the heat exchanger (14). The heat exchanger (14) is an important device for increasing the thermal efficiency. Details of the heat exchanger (14) will be described with reference to the next figure.

Patent document 1 is demonstrated based on the following figure.
As shown in FIG. 10, the heat exchanger 100 includes a base body 102 to which an exhaust gas introduction pipe 101 is connected, a catalyst carrier 103 that is supported by the base body 102 and purifies exhaust gas, and surrounds the catalyst carrier 103 and on the outer periphery. A cylindrical body 105 formed with an exhaust gas restricting portion 104 projecting in a spiral shape, a first case 106 in which exhaust gas flows between the cylindrical body 105 and the cylindrical body 105, and the first case 106 A second case 108 that surrounds the case 106 and supports a plurality of exhaust gas pipes 107 and 107 and in which water is allowed to flow between the exhaust gas pipes 107 and 107, and an exhaust gas connected to the second case 108, respectively. It consists of a gas discharge pipe 111, a water introduction pipe 112, and a water discharge pipe 113.

  As indicated by the white arrow (1), the exhaust gas introduced from the exhaust gas introduction pipe 101 is purified by the catalyst carrier 103 as indicated by the white arrows (2) and (3). The purified exhaust gas flows between the cylinder 105 and the first case 106 toward the upper side of the drawing. Exhaust gas flowing between the cylinder 105 and the first case 106 is guided by the spirally formed exhaust gas restricting portion 104 and flows spirally as indicated by the white arrow (4). Exhaust gas that flows between the cylinder 105 and the first case 106 and reaches the lower surface of the base body 102 passes through the exhaust gas pipes 107 and 107 to the lower side of the drawing, as indicated by the white arrow (5). It flows toward. The exhaust gas that has passed through the exhaust gas pipes 107 and 107 is exhausted from the exhaust gas exhaust pipe 111 as indicated by the white arrow (6).

On the other hand, the water introduced from the water introduction pipe 112 flows through the second case 108 toward the top of the drawing. Similarly to the exhaust gas, water flows spirally in the second case 108.
The water flowing in the second case 108 is warmed by the exhaust gas through the first case 106 and the exhaust gas pipes 107 and 107. The warmed water is discharged from the water discharge pipe 113.

By the way, in order to make exhaust gas flow spirally, the exhaust gas restricting portion 104 is continuously formed in a spiral shape in the circumferential direction of the cylindrical body 105. An example of forming the exhaust gas restricting portion 104 continuously in a spiral manner is a hydraulic forming process.
However, the hydroforming process is difficult to process with high accuracy, and a problem remains in this respect. In other words, it is desired to provide a technology that can process the exhaust gas restricting portion with high accuracy.

JP 2011-21562 A

  This invention makes it a subject to provide the technique which can process an exhaust-gas control part with high precision.

According to the first aspect of the present invention, there is provided a first catalyst carrier for purifying exhaust gas, a catalyst case surrounding the catalyst carrier, and a passage of purified exhaust gas surrounding the catalyst case and the catalyst case. In a heat exchanger comprising a cylinder and a second cylinder that surrounds the first cylinder and forms a passage of water between the first cylinder and the exhaust gas from the first cylinder to the catalyst case A restricting portion protruding, meandering exhaust gas flowing between the catalyst case and the first cylinder, and the exhaust gas restricting portion has an oval shape extending in a circumferential direction of the first cylinder; A plurality of stages are formed in the height direction of the first cylindrical body, and two exhaust gas restricting parts having the same shape are formed in each stage, and these exhaust gas restricting parts are arranged on the central axis of the first cylindrical body. Are formed symmetrically with respect to each other, and such a pair of exhaust gas restricting portions are provided in the adjacent stages. Against air gas regulating portion, formed a phase shifted 90 °, the exhaust gas regulating portion which is two formed in each stage are both based on the axial direction of the central axis of the first cylindrical body, next It overlaps with both the said exhaust-gas control part formed in the step which fits, It is characterized by the above-mentioned .

  In the invention which concerns on Claim 1, the exhaust gas which flows between a catalyst case and a 1st cylinder is meandered by an exhaust-gas control part. In order to meander, the exhaust gas restricting portion is intermittently formed in the circumferential direction of the first cylinder. Since it is formed intermittently, press molding can be used for molding the exhaust gas restricting portion. If it is press molding, an exhaust-gas control part can be processed with high precision. Further, in the case of press molding, the cost for molding is low. Since the first cylinder is inexpensive, the heat exchanger that is a finished product can also be inexpensive.

In addition, two exhaust gas restricting portions having the same shape are formed symmetrically with respect to the central axis in each stage, and the exhaust gas restricting portion has a phase of 90 with respect to the exhaust gas restricting portions in adjacent stages. It is formed with a shift. Since the phases of the exhaust gas restricting portions of adjacent stages are shifted by 90 °, the exhaust gas moves to the next stage after passing through the circumferential direction by approximately 90 °. By making the exhaust gas passage longer, the time for heat exchange can be lengthened. By increasing the heat exchange time, the heat of many exhaust gases can be recovered. Further, by forming the exhaust gas restricting portion, it is possible to increase the contact area where heat can be exchanged.

1 is a cross-sectional view of a heat exchanger according to Embodiment 1. FIG. It is a perspective view of the heat exchanger which concerns on this invention. It is a disassembled perspective view of a base | substrate and a 1st case. It is an expanded view of a 1st cylinder. FIG. 5 is a sectional view taken along line 5-5 of FIG. It is a figure explaining the shaping | molding method of a 1st cylinder. It is a figure explaining after exhaust gas is introduced until it passes a catalyst carrier. It is a figure explaining the flow of the purified exhaust gas, and the flow of water. It is sectional drawing of the heat exchanger which concerns on Example 2. FIG. It is a figure explaining the basic composition of the conventional technology.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

First, Embodiment 1 of the present invention will be described with reference to the drawings.
As shown in FIG. 1, a heat exchanger 10 includes a cylindrical catalyst carrier 11 that purifies exhaust gas, a catalyst case 12 that surrounds and holds the catalyst carrier 11, and a base body on which the catalyst case 12 is supported. 13, a first case 15 that is supported by the base body 13 and surrounds the catalyst case 12, a second case 16 that surrounds the first case 15 and is supported by the base body 13, and the second case 16 A water introduction pipe 17 joined to the side surface in the vicinity of the lower end part to introduce water into the second case 16, and a water discharge pipe 18 joined to the second case 16 above the water introduction pipe 17 to discharge water The exhaust gas exhaust pipe 21 is connected to the lower surface of the base 13 and exhausts exhaust gas that has passed through the base 13. A flange 22 for fastening to another member is joined to the upper end of the base 13.

  The base 13 includes a first member 24 to which the catalyst case 12 is bonded to the lower surface, and a second member 25 to be bonded to the first member 24. The base 13 is formed in a hollow shape by superimposing the first member 24 and the second member 25.

  The first case 15 joined to the second member 25 includes a cylindrical first cylinder 27 surrounding the catalyst case 12 and a lower end of the catalyst carrier 11 joined to the lower end of the first cylinder 27. And a first bottom portion 28 covering the same. The first case 15 can be manufactured by welding the first tubular body 27 and the first bottom portion 28 which are formed by press molding.

  The second case 16 includes a substantially cylindrical second cylinder 31 that surrounds the first cylinder 27, and a second bottom 32 that is joined to the lower end of the second cylinder 31 and covers the first bottom 28. .

  The first member 24 includes a bottom 34 and a wall 35 extending from the periphery of the bottom 34 toward the second member 25. From the opening formed in the bottom 34, the diameter is reduced toward the exhaust gas introduction side (the upper side in the drawing), and a tapered portion 36 formed in a taper shape in cross section is formed. An exhaust gas introduction port 37 into which the exhaust gas is introduced and the flange 22 is attached is formed at the tip of the taper portion 36. The tapered portion 36 and the exhaust gas inlet 37 are formed integrally with the first member 24.

  That is, the exhaust gas introduction port 37 for introducing the exhaust gas, and the tapered portion 36 that continuously expands from the downstream side of the exhaust gas introduction port 37 and smoothly flows the exhaust gas toward the catalyst carrier 11 are provided on the base body. 13 is formed integrally. By forming integrally, the number of parts of the heat exchanger 10 can be reduced.

  The second member 25 includes a bottom 41, a wall portion 42 that rises from the periphery of the bottom 41 toward the first member 24, and an exhaust gas discharge port 43 that discharges exhaust gas that has passed through the base body 13. Consists of. The exhaust gas discharge pipe 21 is joined to the exhaust gas discharge port 43.

  The first member and the second member may employ a structure in which both the bottom part and the wall part are overlapped, and a structure in which the bottom part and the wall part are superimposed on a member having only the bottom part. That is, any shape can be adopted as long as it is hollow. In addition, it is possible to change the shape as appropriate for easy welding, such as welding after extending the wall portions in the outer peripheral direction, or to butt weld each other with the wall portions it can.

An exhaust gas restricting portion 27 a that protrudes from the first cylindrical body 27 toward the catalyst case 12 and restricts the flow path of the exhaust gas when the tip contacts the catalyst case 12 is formed. That is, the exhaust gas flows in a meandering manner so as to avoid the portion where the exhaust gas restricting portion 27a is formed. Details will be described later.
A bulging portion 28 a that bulges toward the catalyst carrier 11 is formed substantially at the center of the first bottom portion 28.

  The second cylindrical body 31 has a general part 31a to which the water introduction pipe 17 is connected and a lower end closed by the second bottom part 32, and a diameter-expanding part to which the diameter of the general cylindrical part 31a is expanded and the water discharge pipe 18 is joined. 31b. A water inlet 31c to which the water inlet pipe 17 is joined is formed in the general part 31a, and a water outlet 31d to which the water outlet pipe 18 is joined is formed in the enlarged diameter part 31b.

The central axis 46 of the general portion 31a of the second cylindrical body 31 is shifted with respect to the central axis 45 of the catalyst carrier 11 in a direction away from the water discharge port 31d.
On the other hand, with respect to the central axis 45 of the catalyst carrier 11, the central axes of the exhaust gas inlet 37, the tapered portion 36, and the first cylinder 27 coincide. The reason why the central axes 45 and 46 are shifted will be described later.
Details of the first member 24 and the second member 25 will be described with reference to the following drawings.

  As shown in FIG. 2, the bottom 34 of the first member 24 includes a general part 34 a formed in a substantially circular shape along the upper part of the second cylindrical body 31, and an exhaust gas discharge port ( 1 and an extending portion 34b that covers the reference numeral 43).

The same applies to the bottom 41 of the second member 25. That is, the second cylinder 31 is covered with the general portion 41a, and the exhaust portion 41b extending from the general portion 41a is provided with the exhaust gas discharge port and the exhaust gas discharge pipe 21 is joined. The extension part 41b may be provided as much as necessary to form the exhaust gas discharge port, and the second member 25 can be made compact compared to the case where the second member 25 is elliptical.
Details of the first cylinder (FIG. 1, reference numeral 27) will be described with reference to the next drawing.

  As shown in FIG. 3, a plurality of exhaust gas restricting portions 27 a are formed in the first cylinder 27. By being formed in a part of the cylindrical first cylindrical body 27, the exhaust gas restricting portion 27a has a substantially C shape in plan view. These exhaust gas restricting portions 27a are formed in the same shape, and are formed at two places at the same height in the height direction. When two exhaust gas restricting portions 27a formed at the same height are set to one stage, such exhaust gas restricting portions 27a are formed in seven stages.

  Although the number of stages of the exhaust gas restricting portion 27a is arbitrary, it is desirable that the exhaust gas restricting portion 27a be arranged as described in the next figure. The first cylinder 27 will be described in more detail with reference to the next drawing.

  FIG. 4 is a view of the first cylindrical body 27 developed and viewed from the inside, and the exhaust gas restricting portion 27a protrudes toward the front side of the drawing. The lengths of the inter-regulator passages 27b formed between the exhaust gas restricting portions 27a and 27a in the same stage (horizontal direction in the drawing) through which the exhaust gas passes are all α.

  A midpoint between the restricting portion passages 27b and 27b formed in the same step is defined as C1. The length P between the two middle points C1 is equal to the length of the half circumference of the first cylinder 27. That is, the midpoint C1 of the inter-regulator passage 27b and the midpoint C1 of the inter-regulator passage 27b are formed 180 degrees apart. The exhaust gas restricting portions 27a formed 180 degrees apart are formed symmetrically with respect to the central axis (FIG. 1, reference numeral 45) of the first cylindrical body 27.

  The midpoint C1 of the inter-regulator passage 27b coincides in the height direction with the midpoint C2 of the exhaust gas restrictor 27a in the adjacent step (the vertical direction in the drawing). That is, they are arranged 90 degrees out of phase with respect to the exhaust gas restricting portions 27a in the adjacent stages.

  The length β of the exhaust gas restricting portion 27a, the length (1/2) α from one end of the exhaust gas restricting portion 27a to the midpoint C1 of the passage 27b between the restricting portions, and between the other end of the exhaust gas restricting portion 27a and the restricting portion A length obtained by adding the length (1/2) α to the midpoint C1 of the passage 27b, and β + (1/2) α · 2 = P is one pitch. In this case, one pitch is 180 °, and it can be said that the exhaust gas restricting portion 27a is arranged 90 ° out of phase with the exhaust gas restricting portion 27a of the adjacent stage.

  One pitch is 120 °, and the phase is shifted by 60 ° with respect to the adjacent exhaust gas restricting portion. One pitch is 90 °, and the phase can be shifted by 45 ° with respect to the adjacent exhaust gas restricting portion. However, from the viewpoint of heat exchange and ease of manufacture, it is desirable that one pitch is 180 ° and the phase is shifted by 90 ° with respect to the adjacent exhaust gas restricting portions.

The exhaust gas restricting portion 27a causes the exhaust gas flowing between the catalyst case (FIG. 1, reference numeral 12) and the first cylinder 27 to meander. In order to meander, the exhaust gas restricting portion 27 a is intermittently formed in the circumferential direction of the first cylindrical body 27. Since it is formed intermittently, press molding can be used for molding the exhaust gas restricting portion 27a. Details of press molding will be described later.
Details of the exhaust gas passage through which the exhaust gas passes and the water passage through which water passes will be described with reference to the following drawings.

As shown in FIG. 5, the central axes of the catalyst case 12 and the first cylinder 27 coincide with the central axis 45 of the catalyst carrier 11. That is, it can be said that the central axis 45 of the catalyst carrier 11 is the central axis 45 of the first cylinder 27.
The central axis 45 of the first cylindrical body 27 is shifted to the water discharge pipe 18 (water discharge port) side by σ1 with respect to the central axis 46 of the general portion 31a of the second cylindrical body 31.
That is, as viewed relatively, the central axis 45 of the first cylinder 27 is disposed closer to the water discharge port side than the central axis 46 of the second cylinder 31.

  The exhaust gas flows in the catalyst carrier 11 from the front to the back of the drawing, and the purified exhaust gas passes through the exhaust gas passage between the catalyst case 12 and the first cylinder 27 from the back to the front of the drawing. To do.

Water flows in the water passage between the first cylinder 27 and the second cylinder 31 from the back of the drawing toward the front. By arranging the central axis 45 of the first cylinder 27 close to the water discharge pipe 18 (water discharge port) side, the water passage formed between the first cylinder 27 and the second cylinder 31 is It is narrow (σ2) on the side of the water discharge pipe 18 and widely formed at a site away from the water discharge pipe 18 (σ3). That is, the flow path area is narrow in the vicinity of the water discharge port, and the flow path area is wide at a site away from the water discharge port. The reason why it is formed in this way will be described later.
A method for forming the first cylinder 27 will be described in detail with reference to the following drawings.

  FIG. 6A is a diagram conceptually showing a press molding apparatus used for molding the first cylinder (FIG. 1, reference numeral 27). The press forming apparatus 50 includes halved columnar punches 51 and 51 and halved columnar dies 52 and 52.

  Each of the punches 51 and 51 has tapered portions 54 and 54 whose diameters are reduced downward in the center, and are formed in a concave shape to form an exhaust gas restricting portion (FIG. 6B, reference numeral 27a). A plurality of concave groove portions 55 are provided. Tension springs 56 and 56 are attached to the upper and lower portions of the punches 51 and 51, respectively.

  The dies 52 and 52 have a plurality of convex portions 57 formed in a convex shape in order to form the exhaust gas restricting portion at portions corresponding to the concave groove portions 55 and 55, respectively. The dies 52, 52 can move in the left-right direction of the drawing.

  An elevating member 59 that can be raised and lowered is provided so as to face between the tapered portions 54 and 54. As for the raising / lowering member 59, the taper surfaces 61 and 61 which contact the taper-shaped parts 54 and 54 each exhibit a rectangle.

  A method for forming the first tubular body by the press forming apparatus 50 will be described. First, a cylindrical material 62 is set between the punches 51 and 51 and the dies 52 and 52. When the material is set, the elevating member 59 is lowered. As the elevating member 59 descends, the punches 51 and 51 move forward in the circumferential direction against the force of the tension springs 56 and 56. The punches 51 and 51 are advanced in the circumferential direction and the dies 52 and 52 are advanced in the center.

  As shown in FIG. 6B, the exhaust gas restricting portion 27 a is formed by sandwiching the material 62 between the punches 51, 51 and the dies 52, 52. As the elevating member 59 is raised, the punches 51 and 51 are retracted toward the center by the force of the tension springs 56 and 56. The punches 51 and 51 are retracted and the dies 52 and 52 are also retracted in the circumferential direction. Thereby, the raw material 62 in which the exhaust gas restricting portion 27a is molded can be taken out.

  By using a punch having a different position where the concave groove portion 55 is formed and a die having a different position where the convex portion 57 is formed, the exhaust gas regulating portion is formed by shifting the phase by 90 ° by the same method. One cylinder can be formed.

If it is press molding, the exhaust gas restricting portion 27a can be processed with high accuracy. Further, in the case of press molding, the cost for molding is low. Since the first cylinder is inexpensive, the heat exchanger (FIG. 1, reference numeral 10), which is a finished product, can also be inexpensive.
The operation of the heat exchanger will be described in the following figures.

  As shown by the arrow (1) in FIG. 7, the exhaust gas introduced from the exhaust gas introduction port 37 flows toward the catalyst carrier 11. The exhaust gas passes through the catalyst carrier 11 and is purified as indicated by the arrow (2). The purified exhaust gas flows from the lower end of the catalyst carrier 11 to between the catalyst case 12 and the first cylinder 27 as indicated by an arrow (3).

By forming the bulging portion 28 a on the first bottom portion 28, the exhaust gas can flow smoothly between the catalyst case 12 and the first cylindrical body 27. That is, the bulging portion 28a serves as a guide for guiding the flow of exhaust gas.
The operation after coming out of the catalyst carrier 11 will be described with reference to the next figure.

  As shown in FIG. 8, the exhaust gas flows upward while meandering so as to avoid the exhaust gas restricting portion 27a. Exhaust gas that meanders and exits from the upper end of the first cylinder 27 passes through the inside of the base 13 and is discharged to the outside through the exhaust gas discharge port 43 and the exhaust gas discharge pipe 21.

  As indicated by the white arrow (5), the water introduced from the water introduction pipe 17 and the water introduction port 31c is directed toward the water discharge port 31d as indicated by the white arrow (6). It passes through the shortest path to the discharge port 31d. The remainder of the introduced water flows around the outer periphery of the first cylinder 27 and flows upward in a portion away from the water discharge port 31d, as indicated by a white arrow (7). The water that flows upward flows outward from the water discharge port 31d and the water discharge pipe 18 as indicated by the white arrow (8). The heat of the exhaust gas is transmitted to the water through the first cylinder 27. That is, the water is warmed.

  Since the phases of the exhaust gas restricting portions 27a in the adjacent stages are shifted by 90 °, the exhaust gas moves to the next stage after passing through the circumferential direction by approximately 90 °. By making the exhaust gas passage longer, the time for heat exchange can be lengthened. By increasing the heat exchange time, the heat of many exhaust gases can be recovered.

  In addition, the base 13 is a hollow body that also includes a first member 24 and a second member 25 joined to the first member 24 and also serves as an exhaust gas passage. The base 13 for supporting the catalyst carrier 11 and the cylinders 27 and 31 is also used as an exhaust gas passage. It is not necessary to provide a separate exhaust gas passage around the periphery of the base 13, and the heat exchanger 10 can be downsized.

  Further, a bulging portion 28 a is formed on the first bottom portion 28. By forming the bulging part 28a, it can be made to flow by a jet and the flow path area of water can be taken large. By increasing the water flow path area, the flow rate of water can be increased. A large flow rate of water prevents a rapid rise in water temperature and prevents water from boiling. By preventing the water from boiling, water can flow smoothly and heat can be exchanged efficiently.

In addition, the flow channel area on the water discharge port 31d side was narrowed, and the flow channel area at a site away from the water discharge port 31d was widened (refer to FIG. 5 as well). By reducing the area of the flow path that passes through the shortest distance from the water inlet 31c to the water outlet 31d, the flow rate of water that passes through the shortest distance is reduced. On the other hand, the flow path area of the part far from the water discharge port 31d and difficult to flow of water is expanded, and the flow rate of water is increased. Thereby, water can be flowed more uniformly over the entire circumference between the first cylinder 27 and the second cylinder 31. By flowing water more uniformly, water can flow smoothly and the efficiency of heat exchange can be improved.
Another embodiment of the present invention will be described in the following figures.

Next, a second embodiment of the present invention will be described with reference to the drawings.
FIG. 9 shows a cross-sectional configuration of the heat exchanger according to the second embodiment, corresponding to FIG.
As shown in FIG. 9, in the heat exchanger 70, the second member 72 constituting the base 71 is integrally formed from the upper end of the first cylinder 73. The second member 72 and the first cylinder 73 are integrally formed by press molding, and the exhaust gas restricting portion 27a is formed by press molding. The second cylinder 31 is attached to the lower surface of the second member 72.

  Even when the second member 72 is formed integrally with the end of the first cylinder 73, the effects of the present invention can be obtained. Further, the first bottom portion 28 may be integrally formed.

  The heat exchanger 70 can reduce the number of parts and the number of assembly steps by integrally forming the second member 72 and the first cylinder 73.

  The heat exchanger according to the present invention can be applied to a cogeneration apparatus and other uses. In the heat exchanger according to the present invention, it is desirable to use cooling water as water, and an optimum type of medium can be used depending on the application.

  The heat exchanger of the present invention is suitable for a cogeneration apparatus.

  DESCRIPTION OF SYMBOLS 10,70 ... Heat exchanger, 11 ... Catalyst carrier, 12 ... Catalyst case, 27, 73 ... 1st cylinder, 27a ... Exhaust gas control part, 31 ... 2nd cylinder, 45 ... Central axis of 1st cylinder .

Claims (1)

A catalyst carrier that purifies exhaust gas, a catalyst case that surrounds the catalyst carrier, a first cylinder that surrounds the catalyst case and forms a passage of purified exhaust gas between the catalyst case, and the first cylinder In a heat exchanger comprising a second cylinder that surrounds the body and forms a passage of water with the first cylinder,
Projecting an exhaust gas restricting portion from the first cylinder to the catalyst case;
Meandering the exhaust gas flowing between the catalyst case and the first cylinder,
The exhaust gas regulation unit,
An oval shape extending in a circumferential direction of the first cylindrical body;
A plurality of stages are formed in the height direction of the first cylinder,
Two exhaust gas restricting portions having the same shape are formed in each stage, and these exhaust gas restricting portions are formed symmetrically with respect to the central axis of the first cylindrical body,
Such a pair of exhaust gas restricting portions is formed with a phase shifted by 90 ° with respect to the exhaust gas restricting portions in adjacent stages ,
The two exhaust gas restricting portions formed at each stage overlap both of the exhaust gas restricting portions formed at two adjacent stages on the basis of the axial direction of the central axis of the first cylindrical body. heat exchanger characterized by that.

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