JP2011202640A - Heat exchanger of stirling engine - Google Patents

Abstract

It is possible to provide a high-density pipe group composed of a plurality of pipes, thereby improving heat exchange performance, and preventing or suppressing generation of noise and wear due to contact between pipes. Provide heat exchanger for Stirling engine.
A heater includes a heat transfer tube group consisting of a plurality of heat transfer tubes that allow a working fluid of the Stirling engine to flow between two cylinders arranged in series and provided in a two-cylinder α-type Stirling engine. ing. The heat transfer tube group 70A includes a rising portion G1, a falling portion G2, and a folded portion G3 that connects the rising portion G1 and the falling portion G2 so as to be reversed. The heater 47A includes a fixing plate 72 that fixes the plurality of heat transfer tubes 71A in the folded portion G3.
[Selection] Figure 3

Description

  The present invention relates to a heat exchanger for a Stirling engine, and in particular, heat exchange of a Stirling engine having a group of pipes that allow a working fluid of the Stirling engine to flow between two cylinders of the two-cylinder α-type Stirling engine. Related to the vessel.

  In recent years, Stirling engines with excellent theoretical thermal efficiency have attracted attention in order to recover exhaust heat and factory exhaust heat of internal combustion engines mounted on vehicles such as passenger cars, buses, and trucks. Stirling engines can be expected to have high thermal efficiency, and because they are external combustion engines that heat the working fluid from the outside, they can utilize various low-temperature differential energy alternatives such as solar, geothermal, and exhaust heat regardless of the heat source, saving energy. There is an advantage that helps. For example, Patent Document 1 discloses a technique that is considered to be related to the present invention in that it relates to a heat exchanger for a Stirling engine and is related to a heat exchanger that includes a plurality of pipes. In addition, for example, Patent Literature 2 discloses a technology that is considered to be related to the present invention as a technology related to heat exchange performance.

JP 2005-108358 A JP 2009-7778 A

  In a two-cylinder α-type Stirling engine in which two cylinders are arranged in series and parallel, a working fluid is circulated between the two cylinders using a shell and tube exchanger or a tubular exchanger. For example, it is conceivable that the shape of the heat exchanger is substantially U-shaped. In this respect, such a shape is considered structurally reasonable even in light of the configuration of a two-cylinder α-type Stirling engine in which two cylinders are arranged in series and parallel. However, in the case of a heat exchanger having a generally U-shape, the pipe length located on the inner side is shorter than the pipe located on the outer side, and the flow resistance is reduced. For this reason, in this case, the flow rate of the working fluid is larger in the pipe located on the inner side than in the pipe located on the outer side. In this case, the heat exchange time for the working fluid flowing through the piping located on the inner side is shorter than that for the working fluid flowing through the piping located on the outer side. In other words, in this case, there is a problem that the thermal efficiency of the Stirling engine is lowered by the action of the working fluid flowing through the piping located inside in this way becoming relatively large.

  On the other hand, for example, the technique disclosed in Patent Document 1 is considered to solve such a problem. However, in the disclosed technology of Patent Document 1, depending on the structure to be applied, such as the structure specifically disclosed in Example 1 of Patent Document 1, interference between tubes becomes a problem because of the heat exchanger. It becomes difficult to provide many tubes, and as a result, it may be difficult to obtain higher heat exchange performance. For this reason, in a two-cylinder α-type Stirling engine in which two cylinders are arranged in parallel in parallel, heat that can provide a high-density pipe group composed of a plurality of pipes without causing the above-described reduction in thermal efficiency. An exchanger is desired. Also, in this case, for example, when a Stirling engine is mounted on a vehicle, there is a concern about the occurrence of noise and wear as a result of the pipes coming into contact with each other by vibration. Therefore, the occurrence of such noise and wear can be prevented or suppressed. desired.

  Therefore, the present invention has been made in view of the above problems, and it is possible to provide a high-density pipe group composed of a plurality of pipes, thereby improving heat exchange performance, and contact between pipes. It is an object of the present invention to provide a heat exchanger for a Stirling engine that can prevent or suppress the generation of noise and wear due to the above.

  The present invention for solving the above-mentioned problems includes a pipe group composed of a plurality of pipes for flowing the working fluid of the Stirling engine between two cylinders arranged in series and parallel provided in a two-cylinder α-type Stirling engine. When the piping group is viewed as extending from one end of the piping group, a rising portion that extends to rise, a falling portion that extends to fall, the rising portion and the falling A heat exchanger of a Stirling engine provided with a connecting part that connects the parts so as to be reversed, and a fixing member that fixes the plurality of pipes at the connecting part.

  Further, in the present invention, when the piping group includes a plurality of the connection portions and the connection portion is viewed as extending from one end, the falling portion is turned over with respect to the rising portion. The rising portion and the falling portion, or the connecting portion, when viewed as extending from one end of the connecting portion, the rising portion is turned over with respect to the falling portion. Thus, it is preferable that the fixing member is configured to fix the plurality of pipes in at least one of the connecting portions connecting the rising portion and the falling portion.

  Further, in the present invention, when the piping group includes a plurality of the connecting portions and the connecting portion is viewed as extending from one end, the rising portion is turned over with respect to the falling portion. In the connecting portion connecting the rising portion and the falling portion, the fixing member fixes the plurality of pipes, and more than the core portion composed of the rising portion, the falling portion, and the connecting portion, The space formed between the core portion and the Stirling engine main body may be configured such that a rectifying member that rectifies the fluid constituting the high-temperature heat source is further provided on the fixing member so that the flow rate is reduced. preferable.

  In the present invention, it is preferable that the fixing member also serves as a positioning with a passage member through which a fluid constituting the high-temperature heat source flows.

  According to the present invention, the plurality of pipes are provided with respect to a pipe connection port provided so as to be arranged in a straight line along the extending direction of the crank axis, and the heat transfer pipe group has a bore of the two cylinders in a top view. It is preferable that the two cylinders are provided so as to protrude from each other, and the two cylinders are arranged in series along the extending direction of the crankshaft line, and are provided in a Stirling engine having four or more cylinders. .

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the high-density piping group which consists of several piping, and can improve heat exchange performance by it. Moreover, according to this invention, generation | occurrence | production of the noise and wear by contact between piping can be prevented or suppressed.

It is a figure which shows the Stirling engine provided with the heater concerning Example 1. FIG. 1 is a schematic configuration diagram of a piston / crank portion of a Stirling engine according to Embodiment 1. FIG. It is a figure which shows the heat exchanger tube and heat exchanger tube group concerning Example 1. FIG. In addition, (a) is a front view, (b) is a side view, and (c) is a top view. It is a figure which shows the heater concerning Example 1 concretely. In addition, (a) is a front view, (b) is a side view, and (c) is a top view. It is a figure which shows the heat exchanger tube and heat exchanger tube group concerning Example 2. FIG. In addition, (a) is a front view, (b) is a side view, and (c) is a top view. It is a figure which shows the heater concerning Example 2 concretely. In addition, (a) is a front view, (b) is a side view, and (c) is a top view. It is a figure which shows the heat exchanger tube and heat exchanger tube group concerning Example 3. FIG. In addition, (a) is a front view, (b) is a side view, and (c) is a top view. It is a figure which shows the heater concerning Example 3 concretely. In addition, (a) is a front view, (b) is a side view, and (c) is a top view.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram schematically showing a Stirling engine 10A including a heater 47A that is a heat exchanger of the Stirling engine according to the present embodiment. The Stirling engine 10A is a two-cylinder α-type Stirling engine. The Stirling engine 10A has a high temperature side cylinder 20 and a low temperature side cylinder 30 which are two cylinders arranged in series and parallel so that the extending direction of the crank axis CL and the cylinder arrangement direction X are parallel to each other. The high temperature side cylinder 20 includes an expansion piston 21 and a high temperature side cylinder 22, and the low temperature side cylinder 30 includes a compression piston 31 and a low temperature side cylinder 32. The compression piston 31 is provided with a phase difference so as to move with a delay of about 90 ° in crank angle with respect to the expansion piston 21.

The upper space of the high temperature side cylinder 22 is an expansion space. The working fluid heated by the heater 47A flows into the expansion space. In the present embodiment, the heater 47A is specifically disposed inside an exhaust pipe 100 of a gasoline engine mounted on a vehicle. In this regard, the Stirling engine 10A is arranged such that the extending direction of the crank axis CL (in other words, the cylinder arrangement direction X) is parallel to the exhaust gas flow direction V1. In the heater 47A, the working fluid is heated by thermal energy recovered from the exhaust gas that is a fluid constituting the high-temperature heat source.
The upper space of the low temperature side cylinder 32 is a compression space. The working fluid cooled by the cooler 45 flows into the compression space.
The regenerator 46 exchanges heat with the working fluid reciprocating between the expansion space and the compression space. Specifically, the regenerator 46 receives heat from the working fluid when the working fluid flows from the expansion space to the compression space, and releases the stored heat to the working fluid when the working fluid flows from the compression space to the expansion space. .
Air is applied to the working fluid. However, the present invention is not limited to this, and a gas such as He, H ₂ , or N ₂ can be applied to the working fluid.

  Next, the operation of the Stirling engine 10A will be described. When the working fluid is heated by the heater 47A, the working fluid expands and the expansion piston 21 is pressed down, whereby the drive shaft (crankshaft) 113 is rotated. Next, when the expansion piston 21 moves up, the working fluid passes through the heater 47A and is transferred to the regenerator 46, where it releases heat and flows to the cooler 45. The working fluid cooled by the cooler 45 flows into the compression space, and is further compressed as the compression piston 31 moves upward. The working fluid thus compressed rises in temperature while taking heat from the regenerator 46 and flows into the heater 47A, where it is heated and expanded again. That is, the Stirling engine 10A operates through the reciprocating flow of the working fluid.

  By the way, in this embodiment, since the heat source of the Stirling engine 10A is exhaust gas of the internal combustion engine of the vehicle, the amount of heat to be obtained is limited, and it is necessary to operate the Stirling engine 10A within the range of the obtained amount of heat. . Therefore, in this embodiment, the internal friction of the Stirling engine 10A is reduced as much as possible. Specifically, gas lubrication is performed between the cylinders 22 and 32 and the pistons 21 and 31 in order to eliminate the friction loss due to the piston ring having the largest friction loss among the internal friction of the Stirling engine 10A.

  In the gas lubrication, the pistons 21 and 31 are made to float in the air by using the pressure (distribution) of air generated by a minute clearance between the cylinders 22 and 32 and the pistons 21 and 31. Since the gas lubrication has an extremely small sliding resistance, the internal friction of the Stirling engine 10A can be greatly reduced. Specifically, for example, static pressure gas lubrication in which a pressurized fluid is ejected and the object is floated by the generated static pressure can be applied to the gas lubrication that floats the object in the air. However, the present invention is not limited to this, and the gas lubrication may be, for example, dynamic pressure gas lubrication.

  The clearance between the cylinders 22 and 32 where the gas lubrication is performed and the pistons 21 and 31 is several tens of μm. Then, the working fluid of the Stirling engine 10A is interposed in this clearance. Each of the pistons 21 and 31 is supported in a non-contact state or an allowable contact state with the cylinders 22 and 32 by gas lubrication. Therefore, a piston ring is not provided around the pistons 21 and 31, and lubricating oil generally used with the piston ring is not used. In gas lubrication, the airtightness of each of the expansion space and the compression space is maintained by minute clearance, and clearance sealing is performed without a ring and without an oil.

  Further, both the pistons 21 and 31 and the cylinders 22 and 32 are made of metal. Specifically, in this embodiment, the corresponding pistons 21 and 31 and the cylinders 22 and 32 have the same linear expansion coefficient (here, SUS). Has been applied. Thereby, even if there is thermal expansion, it is possible to perform gas lubrication while maintaining an appropriate clearance.

  By the way, in the case of gas lubrication, since the load capacity is small, the side force of the pistons 21 and 31 must be made substantially zero. That is, when performing gas lubrication, the ability of the cylinders 22 and 32 to withstand the force in the diametrical direction (lateral direction and thrust direction) (pressure resistance ability) is reduced. The motion accuracy needs to be high.

  For this reason, in this embodiment, a grasshopper mechanism 50 is employed in the piston / crank portion. In addition to the glass hopper mechanism 50, for example, a watt mechanism is available as a mechanism for realizing the linear motion, but the size of the mechanism required for obtaining the same linear motion accuracy is smaller than that of the other mechanisms. As a result, the entire apparatus can be made compact. In particular, since the Stirling engine 10A of this embodiment is installed in a limited space such as under the floor of an automobile, the degree of freedom of installation increases when the entire apparatus is compact. The grasshopper mechanism 50 is advantageous in terms of fuel consumption because the weight of the mechanism required to obtain the same linear motion accuracy is lighter than that of the other mechanisms. Further, the grasshopper mechanism 50 has an advantage that the structure (manufacturing and assembly) is easy because the structure of the mechanism is relatively simple.

  FIG. 2 is a diagram schematically showing a schematic configuration of a piston / crank portion of the Stirling engine 10A. Since the piston / crank portion employs a common configuration for the high temperature side cylinder 20 side and the low temperature side cylinder 30 side, only the high temperature side cylinder 20 side will be described below, and the low temperature side cylinder 30 side will be described. Description of is omitted. The approximate linear mechanism includes a grasshopper mechanism 50, a connecting rod 110, an extension rod 111, and a piston pin 112. The expansion piston 21 is connected to the drive shaft 113 via a connecting rod 110, an extension rod 111, and a piston pin 112. Specifically, the expansion piston 21 is connected to one end side of the extension rod 111 via a piston pin 112. A small end portion 110 a of the connecting rod 110 is connected to the other end side of the extension rod 111. The large end portion 110 b of the connecting rod 110 is connected to the drive shaft 113.

  The reciprocating motion of the expansion piston 21 is transmitted to the drive shaft 113 by the connecting rod 110, where it is converted into a rotational motion. The connecting rod 110 is supported by a grasshopper mechanism 50 and reciprocates the expansion piston 21 linearly. Thus, by supporting the connecting rod 110 by the grasshopper mechanism 50, the side force F of the expansion piston 21 becomes almost zero. For this reason, even when performing gas lubrication with a small load capacity, the expansion piston 21 can be sufficiently supported.

  Next, the heater 47A will be described more specifically with reference to FIG. Here, the heater 47A is a multi-tube heat exchanger, and includes a plurality of heat transfer tubes 71A corresponding to a plurality of pipes through which the working fluid flows. The heat transfer tube 71A has an axisymmetric shape with respect to its central axis, and specifically has a generally V-shaped shape. A first working fluid inlet / outlet P1 is provided at one end of the heat transfer tube 71A, and a second working fluid inlet / outlet P2 is provided at the other end. Specifically, a SUS tube is used as the heat transfer tube 71A.

  The plurality of heat transfer tubes 71A constitute a heat transfer tube group 70A. In FIG. 3, for convenience of explanation, five heat transfer tubes 71A are shown as a plurality of heat transfer tubes 71A constituting the heat transfer tube group 70A, and two heat transfer tube groups 70A are shown. Specifically, the heat transfer tube group 70 </ b> A includes a plurality of heat transfer tubes 71 </ b> A arranged so as to form a one-row assembly. More specifically, the heat transfer tube group 70 </ b> A includes a plurality of heat transfer tubes 71 </ b> A arranged in series and at equal intervals. In this regard, the plurality of heat transfer tubes 71A constituting the heat transfer tube group 70A are specifically arranged in series along the cylinder arrangement direction X. Accordingly, each of the plurality of heat transfer tubes 71A is viewed when viewed along a direction Z perpendicular to the cylinder arrangement direction X and the cylinder extending direction Y with the cylinder arrangement direction X aligned with the horizontal direction as shown in FIG. The shape is symmetrical. Each of the plurality of heat transfer tubes 71A constituting the heat transfer tube group 70A has the same length and the same shape. The heat transfer tube group 70A includes a rising portion G1, a falling portion G2, a folded portion G3, one end G4, and the other end G5.

  The rising portion G1 is an intermediate portion that extends so as to rise when the heat transfer tube group 70A is viewed as extending from one end. Specifically, when the rising portion G1 of the heat transfer tube 71A is viewed as extending away from one end in the cylinder extending direction Y, the rising portion G1 is extended toward the other end in the cylinder arranging direction X. The intermediate portions extending so as to stand up are formed so as to be arranged in a row along the cylinder arrangement direction X. The rising portion G1 configured in this way is arranged along the first plane S1. The first plane S1 is a plane parallel to the cylinder arrangement direction X and the cylinder extending direction Y.

  The falling portion G2 is an intermediate portion that extends so as to fall when the heat transfer tube group 70A is viewed as extending from one end. Specifically, when the falling portion G2 is viewed as extending closer to the other end in the cylinder extending direction Y in the heat transfer tube 71A, the falling portion G2 extends away from one end in the cylinder arranging direction X. Thus, the intermediate portions extending so as to fall are arranged so as to be arranged in a row along the cylinder arrangement direction X. The falling portion G2 is disposed along the second plane S2. The second plane S2 is a plane parallel to the cylinder arrangement direction X and the cylinder extending direction Y, that is, a plane parallel to the first plane S1.

  The folded portion G3 is a portion that connects the rising portion G1 and the falling portion G2 so as to be folded back. In this regard, the folded portion G3 corresponds to a connecting portion that connects the rising portion G1 and the falling portion G2 so as to be reversed. Specifically, the folded portion G3 includes a portion connecting the portion forming the rising portion G1 and the portion forming the falling portion G2 in the heat transfer tube 71A in a row along the cylinder arrangement direction X. It is formed by being arranged so as to form a set. In this respect, the turning portion G3 connects the rising portion G1 and the falling portion G2 at the same height in the cylinder extending direction Y. The folded portion G3 is convex in the same direction as the convex shape formed in the heat transfer tube group 70A by folding, and a top is formed at the center in the direction Z.

  The folded portion G3 includes a pair of bent end portions E in which a rising portion G1 and a falling portion G2 are continuous. The pair of bent ends E are offset from each other, specifically, are offset equally from each other with the direction Z as the offset direction. The offset interval between the pair of bent ends E is set to an interval W that can form a gap between the rising portion G1 and the falling portion G2 in the offset direction. For this reason, the first and second planes S1 and S2 also have an offset interval of the interval W, and the rising portion G1 disposed along the first plane S1 and the second plane parallel to the first plane S1. The falling portion G2 arranged along the plane S2 has an offset interval of the interval W, and as shown in FIG. 3 (b), there is a gap in the offset direction when viewed along the cylinder arrangement direction X. Is provided.

The one end G4 is an end provided on the high temperature side cylinder 20 side. Specifically, one end G4 of the heat transfer tube 71A extends from one end located in the middle of the first and second planes S1 and S2 so as to rise along the cylinder extending direction Y, and the portion From the first plane S1 to the first plane S1 side, extending perpendicularly to the cylinder extending direction Y while being orthogonal to the cylinder arrangement direction X, and a portion connected to a portion forming the rising portion G1 The portions are formed so as to be arranged in a single row along the cylinder arrangement direction X.
The other end G5 is an end provided on the low temperature side cylinder 30 side. Specifically, the other end G5 of the heat transfer tube 71A extends from the other end located between the first and second planes S1 and S2 so as to rise along the cylinder extending direction Y. A portion that extends from the portion toward the second plane S2 so as to rise obliquely with respect to the cylinder extending direction Y while being orthogonal to the cylinder arrangement direction X, and is connected to a portion that forms the falling portion G2. Are arranged so as to form a one-row assembly along the cylinder arrangement direction X.
When the positions of the one end G4 and the other end G5 are different along the cylinder extending direction Y of the upper portion of the high temperature side cylinder 20 and the regenerator 46, the cylinder extending directions of the one end and the other end of the heat transfer tube group 70A are different. The position along Y is adjustable.

  In the heat transfer tube group 70A, the first working fluid inlets / outlets P1 provided at the one end G4 are arranged on the same straight line. In addition, the second working fluid inlet / outlet P2 provided at the other end G5 is arranged on the same straight line. Further, each of the first and second working fluid inlets / outlets P1, P2 is a third plane S3 parallel to the cylinder arrangement direction X and the cylinder extending direction Y (that is, parallel to the first and second planes S1, S2). Included. In this regard, the third plane S3 is located in the center between the first and second planes S1 and S2. Therefore, the first and second planes S1 and S2 are parallel to each other with the third plane S3 including the first and second working fluid inlets and outlets P1 and P2 interposed therebetween.

  A fixing plate 72 as a fixing member is provided in the folded portion G3. For convenience of illustration, the fixing plate 72 is not shown in FIG. The fixing plate 72 fixes the plurality of heat transfer tubes 71A at the turn-back portion G3. Specifically, the fixing plate 72 is provided on the surface side in the folded portion G3, and fixes the plurality of heat transfer tubes 71A by fixing the top of the folded portion G3. Further, the fixing plate 72 is common among the plurality of heat transfer tube groups 70A, and fixes the plurality of heat transfer tubes 71A in each of the folded portions G3 of the plurality of heat transfer tube groups 70A. Each heat transfer tube 71A can be fixed to the fixed plate 72 by welding, for example.

Specifically, the heat transfer tube group 70A constitutes a heater 47A as shown in FIG. For convenience of illustration, the fixing plate 72 is not shown in FIG. In this regard, the fixing plate 72 can be formed to have a rectangular shape, for example, when viewed from above, or to have a shape that leaves only necessary portions. In the heater 47A, as shown in FIG. 4C, the first heat transfer tube connection port B1 for connecting the first working fluid inlet / outlet P1 is provided on the high temperature side cylinder 20 side. The first heat transfer tube connection ports B1 are provided at equal intervals along the cylinder arrangement direction X, and are provided at equal intervals along the direction Z. Therefore, the first heat transfer tube connection ports B1 adjacent to each other along the cylinder arrangement direction X are provided on the same straight line along the cylinder arrangement direction X.
Further, in the heater 47A, as shown in FIG. 4C, the second heat transfer tube connection port B2 for connecting the second working fluid inlet / outlet P2 is provided on the low temperature side cylinder 30 side. Each of the second heat transfer tube connection ports B2 is provided at equal intervals along the cylinder arrangement direction X and at equal intervals along the direction Z. For this reason, the second heat transfer tube connection ports B2 adjacent along the cylinder arrangement direction X are also provided on the same straight line along the cylinder arrangement direction X.

  The numbers of the first and second heat transfer tube connection ports B1 and B2 are equal to each other. The interval along the cylinder arrangement direction X between the first heat transfer tube connection ports B1 and the interval along the cylinder arrangement direction X between the second heat transfer tube connection ports B2 are equal to each other. An interval along the direction Z between the heat transfer tube connection ports B1 and an interval along the direction Z between the second heat transfer tube connection ports B2 are also equal to each other. Further, the first and second heat transfer tube connection ports B1 and B2 have the same number of first heat transfer tube connection ports B1 provided along the cylinder arrangement direction X when the positions along the direction Z are the same. The number of second heat transfer tube connection ports B2 provided along the cylinder arrangement direction X is set to be equal to each other. Accordingly, the same number of first and second heat transfer tube connection ports B1 and B2 are provided at equal positions on the same straight line along the cylinder arrangement direction X at each position along the direction Z. Further, the interval between the first and second heat transfer tube connection ports B1 and B2 provided in the same arrangement and the interval between the first and second working fluid inlets and outlets P1 and P2 of the heat transfer tube 71A are equal to each other. ing.

In the heater 47A, a heat transfer tube 71A is provided for each set of the first and second heat transfer tube connection ports B1 and B2 provided in the same arrangement. In this regard, at each position along the direction Z, the heat transfer tube 71A is connected to the cylinder arrangement direction X with respect to the first and second heat transfer tube connection ports B1 and B2 provided on the same straight line along the cylinder arrangement direction X. Are arranged in parallel with each other at equal intervals, and constitute a plurality of heat transfer tube groups 70A.
On the other hand, the fixing plate 72 fixes a plurality of heat transfer tubes 71A in each of the folded portions G3 of each heat transfer tube group 70A. The fixing plate 72 also serves as a positioning with the exhaust pipe 100 that is a passage member for circulating the exhaust gas. In this regard, when the fixing plate 72 is caused to function as positioning, for example, the fixing plate 72 or a concavo-convex portion provided as a part of the fixing plate 72 is engaged at a regular position so as to prevent the movement of the fixing plate 72. The engaging portion can be provided in the exhaust pipe 100. The fixing plate 72 may function as positioning by being fixed to the exhaust pipe 100 at a regular position, for example.

Next, the effect of the heater 47A will be described. In the heater 47A, the heat transfer tube group 70A includes a folded portion G3 that folds the falling portion G2 with respect to the rising portion G1 and connects them. According to such a structure, it becomes possible to arrange a plurality of heat transfer tubes 71 </ b> A constituting the heat transfer tube group 70 </ b> A densely in a single row. For this reason, the heater 47A can increase the density of the heat transfer tube group 70A, thereby realizing high heat exchange performance.
On the other hand, when the plurality of heat transfer tubes 71A are provided at a high density, there is a concern that the plurality of heat transfer tubes 71A come into contact with each other due to vibration, resulting in noise and wear. On the other hand, the heater 47A includes a fixing plate 72 that fixes the plurality of heat transfer tubes 71A in the folded portion G3. For this reason, the heater 47A can prevent or suppress the occurrence of noise and wear due to contact between the heat transfer tubes 71A.
Further, in the heater 47A, the fixed plate 72 fixes the plurality of heat transfer tubes 71A in each of the folded portions G3 of the heat transfer tube groups 70A. For this reason, in the heater 47A, the heat transfer tubes 71A of the adjacent heat transfer tube group 70A come into contact with each other by vibration, and as a result, the occurrence of noise and wear can be prevented or suppressed.

Further, the heater 47A fixes the plurality of heat transfer tubes 71A at the turn-back portion G3 by the fixing plate 72, so that the heat transfer tubes 71A along the cylinder arrangement direction X are thermally deformed at the rising portion G1 and the falling portion G2. While allowing, it is also possible to prevent or suppress the occurrence of noise and wear due to contact between the heat transfer tubes 71A.
Further, in the heater 47A, the fixing plate 72 fixes the plurality of heat transfer tubes 71A at the turn-back portion G3 so that the direction of thermal deformation of each heat transfer tube 71A generated along the direction Z at the rising portion G1 or the rising portion G2 is determined. Thus, it is possible to prevent or suppress the occurrence of noise and wear due to contact between the heat transfer tubes 71A while allowing thermal deformation of the heat transfer tubes 71A along the direction Z. In this regard, when aligning the direction of thermal deformation of each heat transfer tube 71A, for example, between the rising portions G1 of each heat transfer tube 71A and between each falling portion G2 of each heat transfer tube 71A, the direction is when the engine is cold. A plurality of heat transfer tubes 71 </ b> A can be fixed by a fixing plate 72 so as to have a deflection in the same direction along Z.
In this regard, in the heater 47A, when fixing the plurality of heat transfer tubes 71A, the fixing plate 72 fixes the top of the folded portion G3. For this reason, for example, the heater 47A has a higher degree of freedom of thermal deformation generated in each heat transfer tube 71A than in the case where the portion of the heat transfer tube 71A in which the folded portion G3 is formed is fixed as a whole. As a result, thermal deformation generated in each heat transfer tube 71A can be suitably allowed.

Further, in the heater 47A, the fixed plate 72 also serves as positioning with the exhaust pipe 100. For this reason, in the heater 47A, it is possible to restrict the movement of the heat transfer tubes 71A due to vibration and thermal deformation in the exhaust pipe 100, which may cause noise and wear due to contact between the heat transfer tubes 71A. Can be prevented.
In addition, the heater 47A fixes the plurality of heat transfer tubes 71A and includes a fixing plate 72 that functions as a positioning so that fins are provided to the heat transfer tubes 71A so as not to cause noise and wear due to contact. This also facilitates the heat exchange performance.

The heater 47B according to the present embodiment includes a plurality of heat transfer tubes 71B shown in FIG. 5 as a multitubular heat exchanger. The heat transfer tube 71B has an axisymmetric shape with respect to its central axis, and specifically has a generally M-shaped shape. A first working fluid inlet / outlet P1 is provided at one end of the heat transfer tube 71B, and a second working fluid inlet / outlet P2 is provided at the other end.
And the some heat exchanger tube 71B comprises the heat exchanger tube group 70B. In FIG. 5, for convenience of explanation, two heat transfer tubes 71B are shown as the plurality of heat transfer tubes 71B constituting the heat transfer tube group 70B, and two heat transfer tube groups 70B are shown. The plurality of heat transfer tubes 71B are equal in length and have the same shape, and the heat transfer tube group 70B is configured in the same manner as the plurality of heat transfer tubes 71A configure the heat transfer tube group 70A.

  The heat transfer tube group 70B includes two rising portions G1, two falling portions G2, three folded portions G3, one end portion G4, and the other end portion G5. In this regard, the heat transfer tube group 70B is provided with a plurality of folded portions G3, so that a new rising portion G1 and a new falling portion G2 are further provided structurally with respect to the heat transfer tube group 70A. It is a group. Note that the number of the plurality of folded portions G3 is specifically an odd number.

Specifically, when the two rising portions G1 are viewed as the heat transfer tube group 70B extending from one end, the rising portion G11 located on one end side, and the rising portion G12 located on the other end side, It is constituted by. Each of these two rising portions G1 extends in parallel to each other and is disposed along the first plane S1.
Specifically, the two falling parts G2 are a falling part G21 located on one end side and a falling part located on the other end side when the heat transfer tube group 70B is viewed as extending from one end. Part G22. Each of these two falling portions G2 extends in parallel to each other and is disposed along the second plane S2.

  Specifically, when the three folded portions G3 are viewed as the heat transfer tube group 70B extending from one end, the falling portion G2 is folded with respect to the rising portion G1, and the rising portion G1 The two folded portions G31 connecting the falling portion G2 and the one folded portion G32 connecting the rising portion G1 and the falling portion G2 so as to fold the rising portion G1 with respect to the falling portion G2. ing. The two folded portions G31 are located at both ends in the heat transfer tube group 70B, and the folded portions G32 are located in the center in the heat transfer tube group 70B.

These three folded portions G3 are configured to connect the rising portion G1 and the falling portion G2 at the same height in the cylinder extending direction Y. Further, the three folded portions G3 are convex in the same direction as the convex shape formed in the heat transfer tube group 70B by folding, and a top is formed at the center in the direction Z.
Further, in each of these three folded portions G3, a pair of bent end portions E are provided in the same manner as in the case of the heat transfer tube group 70A, and the rising portion G1 and the falling portion G2 have an offset interval of the interval W. Thus, as shown in FIG. 5B, when viewed along the cylinder arrangement direction X, a gap is formed in the offset direction.

The one end G4 is an end provided on the high temperature side cylinder 20 side. Specifically, the cylinder extending direction Y extends from one end located between the first and second planes S1 and S2 in the heat transfer tube 71B. A portion extending so as to rise along the cylinder, and extending from the portion toward the first plane S1 so as to rise obliquely with respect to the cylinder extending direction Y while being orthogonal to the cylinder arranging direction X, A portion composed of a portion connected to a portion forming the rising portion G11 located on the side is formed by being arranged along the cylinder arrangement direction X so as to form a one-row set.
The other end G5 is an end provided on the low temperature side cylinder 30 side. Specifically, in the heat transfer tube 71B, the cylinder extends from the other end located between the first and second planes S1 and S2. A portion extending so as to rise along the direction Y, and extending from the portion toward the second plane S2 so as to stand obliquely with respect to the cylinder extending direction Y while being orthogonal to the cylinder arrangement direction X A portion including a portion connected to a portion forming the falling portion G22 located on the other end side is formed by being arranged so as to form a one-row assembly along the cylinder arrangement direction X. ing.

  A fixed plate 72 is provided in the folded portion G3. For convenience of illustration, the fixing plate 72 is not shown in FIG. Specifically, the fixing plate 72 is provided for each of the three folded portions G3, and fixes the plurality of heat transfer tubes 71B in each of the folded portions G3. Each fixing plate 72 fixes the plurality of heat transfer tubes 71B by fixing the top of the folded portion G3 in each folded portion G3. Further, each fixing plate 72 is common to each of the plurality of heat transfer tube groups 70B, and fixes the plurality of heat transfer tubes 71B in each of the folded portions G3 of the plurality of heat transfer tube groups 70B.

Specifically, the heat transfer tube group 70B constitutes a heater 47B as shown in FIG. For convenience of illustration, the fixing plate 72 is not shown in FIG. In this regard, the specific shape of the fixing plate 72 may be different from that in the first embodiment, and the specific shape of each fixing plate 72 may be different from each other. The Stirling engine 10B is substantially the same as the Stirling engine 10A except that the heater 47B is provided instead of the heater 47A.
In the heater 47B, the first and second heat transfer tube connection ports B1 and B2 are provided in the same manner as in the case of the heater 47A. Further, in the heater 47B, a heat transfer tube 71B is provided for each set of the first and second heat transfer tube connection ports B1 and B2 provided in the same arrangement as in the case of the heater 47A. Thus, a plurality of heat transfer tube groups 70B are configured along the direction Z.
On the other hand, each fixing plate 72 fixes a plurality of heat transfer tubes 71B in each folded portion G3 of each heat transfer tube group 70B. Each fixing plate 72 also serves as a positioning with the exhaust pipe 100. In this respect, in the fixed plate 72 provided in the turned-back portion G32, portions located at the center in the cylinder arrangement direction X and at both ends in the direction Z also serve as positioning with the exhaust pipe 100.

  Further, in the heater 47B, a rectifying plate 73 is provided on the fixed plate 72 provided in the folded portion G32. Specifically, the rectifying plate 73 has a surface orthogonal to the cylinder arrangement direction X, and is provided so as to extend along the cylinder extending direction Y from the surface side portion of the fixed plate 72 provided in the folded portion G32. It has been. The rectifying plate 73 is connected to the Stirling engine 10B main body, which is a portion of the Stirling engine 10B excluding the heater 47B, rather than the flow rate of the exhaust gas flowing through the core portion C composed of the rising portion G1, the falling portion G2, and the folded portion G3. The rectifying member rectifies the exhaust gas flowing through the exhaust pipe 100 so that the flow rate of the exhaust gas flowing through the space T formed between the core portion C and the core portion C is reduced. In this regard, for example, a plate-like member capable of blocking exhaust gas flowing through the space T can be applied to the rectifying plate 73. The rectifying plate 73 is a plate-like member provided with a mesh or a hole that can reduce the flow rate of the exhaust gas flowing through the space T by increasing the pressure loss of the exhaust gas flowing through the space T, for example. Etc. can be applied.

Next, the effect of the heater 47B will be described. In the heater 47B, a new rising portion G1 and a new falling portion G2 can be further provided with respect to the heater 47A by providing a plurality of folded portions G3. That is, in the heater 47B, by providing the plurality of folded portions G3, the total length of the plurality of heat transfer tubes 71B constituting the heat transfer tube group 70B is made larger than the total length of the plurality of heat transfer tubes 71A constituting the heat transfer tube group 70A. And a larger heat transfer area can be secured as compared with the heater 47A.
In the heater 47B, the heat transfer tube group 70B is configured by a plurality of heat transfer tubes 71B having a substantially M-shaped shape, so that the folded portion G32 is arranged in the cylinder arrangement direction X, which is the arrangement direction of the plurality of heat transfer tubes 71B. Each folded portion G3 is provided so as to be positioned between adjacent folded portions G31, thereby ensuring a compact form. For this reason, the heater 47B can implement | achieve the heat exchange performance still more suitably at the point which can aim at the further improvement of heat exchange performance, ensuring a compact form compared with the heater 47A.

On the other hand, in the heater 47B, as a result of providing the plurality of heat transfer tubes 71B at a high density, the plurality of heat transfer tubes 71B come into contact with each other due to vibration, and as a result, there is a concern that noise and wear may occur. On the other hand, the heater 47B includes a fixing plate 72 that fixes the plurality of heat transfer tubes 71B at the turn-back portion G3, and the fixing plate 72 also serves as a positioning so that the same effect as the heater 47A can be achieved. it can.
Further, in the heater 47B, a rectifying plate 73 is provided on the fixed plate 72 provided in the folded portion G32. For this reason, the heater 47B can further improve the heat exchange performance by increasing the flow rate of the exhaust gas flowing through the core C.

The heater 47C according to the present embodiment includes a plurality of heat transfer tubes 71C shown in FIG. 7 as a multi-tube heat exchanger. The heat transfer tube 71C has an axisymmetric shape with respect to its central axis, and specifically has a generally M-shaped shape. A first working fluid inlet / outlet P1 is provided at one end of the heat transfer tube 71C, and a second working fluid inlet / outlet P2 is provided at the other end.
The plurality of heat transfer tubes 71C constitute a heat transfer tube group 70C. In FIG. 7, for convenience of explanation, two heat transfer tubes 71C are shown as a plurality of heat transfer tubes 71C constituting the heat transfer tube group 70C, and two heat transfer tube groups 70C are shown. The plurality of heat transfer tubes 71C are equal in length and have the same shape, and the heat transfer tube group 70C is configured in the same manner as the plurality of heat transfer tubes 71A configure the heat transfer tube group 70A.

The heat transfer tube group 70C is substantially the same as the heat transfer tube group 70B except that the one end G4 and the other end G5 are formed differently.
That is, in the heat transfer tube group 70C, one end G4 of the heat transfer tube 71C extends from one end located in the middle of the first and second planes S1 and S2 so as to rise along the cylinder extending direction Y. The portion extending from the portion to the first plane S1 side and extending outwardly obliquely with respect to the cylinder arrangement direction X and the cylinder extending direction Y, and forming a rising portion G11 located on one end side The portions composed of the connected portions are formed so as to be arranged in a row along the cylinder arrangement direction X.
In the heat transfer tube group 70C, the other end G5 is extended so as to rise along the cylinder extending direction Y from the other end of the heat transfer tube 71C located between the first and second planes S1 and S2. A portion and a falling portion G22 extending from the portion to the second plane S2 side and to the outside so as to rise obliquely with respect to the cylinder arrangement direction X and the cylinder extending direction Y, and located on the other end side A portion composed of a portion connected to the portion to be formed is formed by being arranged in a row along the cylinder arrangement direction X.
A fixed plate 72 is provided in the folded portion G3 as in the case of the heat transfer tube group 70B. For convenience of illustration, the fixing plate 72 is not shown in FIG.

  Specifically, the heat transfer tube group 70C constitutes a heater 47C as shown in FIG. For convenience of illustration, the fixing plate 72 is not shown in FIG. In this regard, the specific shape of the fixing plate 72 may be different from those in the first and second embodiments, and the specific shape of each fixing plate 72 may be different from each other. Further, the Stirling engine 10C has a large number of four cylinders by arranging a plurality (two in this case) of a pair of cylinders 20 and 30 of the Stirling engine 10A along the extending direction of the crank axis CL (in other words, the cylinder arrangement direction X). Other than the point that it is made into a cylinder and a plurality of (in this case, two) heaters 47C provided corresponding to each of the pair of cylinders 20 and 30 instead of the heater 47A, It is substantially the same as the Stirling engine 10A.

  In the heater 47C, the first and second heat transfer tube connection ports B1 and B2 are provided in the same manner as the heater 47A so as to correspond to the pair of cylinders 20 and 30, respectively. In this respect, the first and second heat transfer tube connection ports B1 and B2 are arranged not only in each heater 47C but also between each heater 47C in a straight line along the extending direction of the crank axis CL. Yes. In the heater 47C, a heat transfer tube 71C is provided for each set of the first and second heat transfer tube connection ports B1 and B2 provided in the same arrangement as in the case of the heater 47A. A plurality of heat transfer tube groups 70C are configured along the direction Z.

In each heater 47C, as shown in FIG. 8C, a heat transfer tube group 70C is provided so as to protrude from the respective bores of the pair of cylinders 20 and 30 in a top view. In this regard, the rising portion G11 mainly protrudes from the bore on the high temperature side cylinder 20 side, and the falling portion G22 mainly protrudes from the bore on the low temperature side cylinder 30 side. And, due to the structure of the heat transfer tube group 70C that connects the rising portion G1 and the falling portion G2 so as to be reversed, the rising portion G11 and the falling portion G22 are opposite to each other along the direction Z in the same heat transfer tube group 70C. It is offset in the direction.
Each fixing plate 72 fixes a plurality of heat transfer tubes 71C in the folded portion G3 of each heat transfer tube group 70C as well as the heater 47B, and also serves as a positioning with the exhaust pipe 100. In addition, a rectifying plate 73 is provided on the fixed plate 72 provided in the folded portion G32 as in the case of the heater 47B.

Next, the effect of the heater 47C will be described. The heater 47C includes a fixed plate 72 and a rectifying plate 73 in the same manner as the heater 47B. For this reason, the heater 47C can exhibit the same effects as the heater 47B.
Further, in the heater 47C, by providing the heat transfer tube group 70C so as to protrude from the bore, it is possible to further increase the overall length as compared with the heater 47B and to shorten the bore pitch of the pair of cylinders 20 and 30. As a result, the heat exchange performance can be further improved, and the Stirling engine 10C can be made compact.

On the other hand, when the heater 47C provided so that the heat transfer tube group 70C extends from the bore is provided in the multi-cylinder Stirling engine 10C, interference between the heat transfer tube groups 70C does not occur between the heaters 47C. There is a need.
In this regard, in the Stirling engine 10C in which a plurality of cylinders 20 and 30 are arranged side by side along the extending direction of the crank axis CL, the first and second heat transfer tube connection ports B1 and B2 are The heaters 47C are arranged not only in each heater 47C but also between the heaters 47C along the extending direction of the crank axis CL. For this reason, in the Stirling engine 10C, between the heaters 47C, the opposing portions of the heat transfer tube groups 70C are offset in the opposite directions along the direction Z, whereby the cylinders are arranged between the heaters 47C. Interference can be avoided while having overlapping positions in the direction X.
Therefore, the heater 47C can be provided close to each other in the multi-cylinder Stirling engine 10C even when the heat transfer tube group 70C is provided so as to protrude from the bore. It can also contribute to downsizing.

The embodiment described above is a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.
For example, in the second and third embodiments described above, the case where the fixing plate 72 is provided in any of the folded portions G31 and G32 that are a plurality of connecting portions has been described. However, the present invention is not necessarily limited to this, and it is possible to prevent or suppress the occurrence of noise and wear due to contact by providing a fixing member in at least one of the plurality of connecting portions.
For example, in the above-described embodiment, the case where each heat transfer tube is a SUS tube has been described. However, the present invention is not necessarily limited to this, and the plurality of pipes may be, for example, pipes having an elliptical cross section or pipes having other shapes.
Further, for example, in the above-described embodiment, a case has been described in which each heat transfer tube group includes the folded portion G3 that connects the rising portion G1 and the falling portion G2 so as to be folded. However, the present invention is not necessarily limited to this, and the piping group may include, for example, a connecting portion that smoothly connects the rising portion and the falling portion so as to be reversed instead of the folded portion.

10A, 10B, 10C Stirling engine 20 High temperature side cylinder 21 Expansion piston 22 High temperature side cylinder 30 Low temperature side cylinder 31 Compression piston 32 Low temperature side cylinder 47A, 47B, 47C Heater 50 Grasshopper mechanism 70A, 70B, 70C Heat transfer tube group 71A, 71B, 71C Heat transfer tube 72 Fixed plate 73 Current plate

Claims (5)

A pipe group consisting of a plurality of pipes for flowing the working fluid of the Stirling engine between two cylinders arranged in series and parallel provided in the two-cylinder α-type Stirling engine;
When the piping group is viewed as extending from one end of the piping group, a rising portion that extends to rise, a falling portion that extends to fall, the rising portion and the falling With a connecting part that connects the part upside down,
A heat exchanger for a Stirling engine provided with a fixing member for fixing the plurality of pipes in the connecting portion. A heat exchanger for a Stirling engine according to claim 1,
The piping group includes a plurality of the connection portions,
Of the connection parts, when viewed as extending from one end, the connection part connecting the rising part and the falling part so that the falling part is turned over with respect to the rising part, Or, when it is viewed as extending from one end of the connecting portion, the connecting portion that connects the rising portion and the falling portion so that the rising portion is turned over with respect to the falling portion A heat exchanger for a Stirling engine in which the fixing member fixes the plurality of pipes in at least one of the connection portions. A heat exchanger for a Stirling engine according to claim 1,
The piping group includes a plurality of the connection portions,
Among the connection parts, when viewed as extending from one end, the connection part connecting the rising part and the falling part so that the rising part is turned over with respect to the falling part. The fixing member fixes the plurality of pipes;
The high temperature heat source is configured so that the flow rate is smaller in the space formed between the core portion and the Stirling engine body than the core portion including the rising portion, the falling portion, and the connecting portion. A heat exchanger for a Stirling engine, wherein a rectifying member for rectifying fluid is further provided on the fixed member. A heat exchanger for a Stirling engine according to any one of claims 1 to 3,
A heat exchanger for a Stirling engine in which the fixing member also functions as a positioning member with a passage member for allowing a fluid constituting a high-temperature heat source to flow therethrough. A heat exchanger for a Stirling engine according to any one of claims 1 to 4,
The plurality of pipes are provided with respect to pipe connection ports provided so as to be arranged in a straight line along the extending direction of the crank axis, and the heat transfer tube group is stretched from each of the bores of the two cylinders in a top view. It is provided to put out,
A heat exchanger for a Stirling engine provided in a Stirling engine in which the two cylinders are arranged in series along the extending direction of the crank axis so that the number of cylinders is four or more.

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