heat exchanger

Abstract

To provide a heat exchanger which enables improvement of heat exchange performance.SOLUTION: A heat exchanger includes: a pipe forming a passage in which a first fluid is supplied; a pair of pipe plates which are provided spaced apart from each other in an extending direction of the passage so as to close the passage to define a closed space at a part of the passage; a plurality of heat transfer pipes which form pipe shapes in which both ends are open, extend so as to penetrate through the pair of pipe plates, and are arranged parallel to each other with a space; a supply part capable of supplying a second fluid to the closed space from the outside of the pipe; a discharge part which can discharge the second fluid in the closed space to the outside of the pipe; partition members which partition the passage around the heat transfer pipe into multiple small passages which extend in an axial direction of the heat transfer pipe and divided in a circumferential direction; and a rib line provided at the small passage and having a plurality of ribs which are arranged spaced apart from each other in the axial direction of the heat transfer pipe.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a heat exchanger. [Background technology]

[0002] In heat engines, including internal combustion engines and external combustion engines, thermal energy is generated by burning fuel, and this thermal energy is extracted as rotational energy of an output shaft, for example. At this time, high-temperature exhaust gas is generated from the heat engine. To effectively utilize the thermal energy of the exhaust gas, a heat exchanger can be installed in the exhaust gas flow path.

[0003] Conventionally, heat exchangers generally have a configuration with multiple heat transfer tubes and fins attached to each heat transfer tube. In this type of heat exchanger, a heat transfer medium flows inside the heat transfer tubes, and another medium flows outside the heat transfer tubes. This allows heat exchange between the two media via the fins. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7025521 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the refrigerant is oil, fuel, or an organic liquid such as Fluorinert, the heat transfer efficiency is low, and even when such a refrigerant with low heat transfer efficiency is used, there is a demand for improved heat exchange performance to ensure sufficient heat exchange.

[0006] The present disclosure has been made to solve the above-mentioned problems, and has an object to provide a heat exchanger that can improve heat exchange performance. [Means for solving the problem]

[0007] In order to solve the above problems, the heat exchanger of the present disclosure includes piping that forms a flow path through which a first fluid is supplied, a pair of tube plates that are arranged at intervals in the extension direction of the flow path so as to close the flow path, thereby defining a closed space in part of the flow path, a plurality of heat transfer tubes that are tubular and open at both ends, extend to penetrate the pair of tube plates, and are arranged side by side at intervals from each other, a supply section that can supply a second fluid from outside the piping into the closed space, a discharge section that can discharge the second fluid in the closed space to the outside of the piping, a partition member that divides the flow path around the heat transfer tube into a plurality of small flow paths that extend in the axial direction of the heat transfer tube and are divided circumferentially, and a rib row that is provided in the small flow path and has a plurality of ribs that are arranged at intervals in the axial direction of the heat transfer tube. [Effects of the Invention]

[0008] According to the heat exchanger of the present disclosure, it is possible to improve heat exchange performance. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a diagram illustrating a configuration of a heat exchanger according to the first embodiment of the present disclosure. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 2 is a plan view of a small flow path according to the first embodiment of the present disclosure. [Figure 4] FIG. 2 is a cross-sectional view taken along line III-III in FIG. [Figure 5] FIG. 10 is a plan view of a small flow path according to a modified example of the first embodiment of the present disclosure. [Figure 6] FIG. 10 is a plan view of a small flow path according to a second embodiment of the present disclosure. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. [Figure 8] FIG. 10 is a cross-sectional view of a supply section according to a modified example of the embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] First Embodiment Hereinafter, a heat exchanger 1 according to an embodiment of the present disclosure will be described with reference to FIGS. The heat exchanger 1 is used to cool a fluid (hereinafter referred to as a first fluid F1), such as high-temperature exhaust gas discharged from a heat engine or other heat source, by exchanging heat between the first fluid F1 and water (hereinafter referred to as a second fluid F2).

[0011] As shown in Figures 1 and 2, the heat exchanger 1 includes a pipe 10, a vane 2, a tube plate 3, a heat transfer tube 4, a supply section 20, a discharge section 30, a partition member 40, and a rib row 50.

[0012] (Plumbing) The pipe 10 forms a flow path P to which the first fluid F1 is supplied. The pipe 10 has a straight pipe body 11 and elbow portions 12 provided at both ends of the pipe body 11. The piping body 11 accommodates the heat transfer tubes 4 described below inside. The piping body 11 is formed in a polygonal shape so as to fit the outer shape of the bundle of heat transfer tubes 4.

[0013] The elbow portion 12 forms a bend. A plurality of vanes 2 are provided inside the elbow portion 12 to guide the flow direction of the first fluid F1 to match the bend. Furthermore, a tube sheet 3 that closes the flow path P is provided at the end of each elbow portion 12 on the piping main body 11 side. A supply portion 20 is provided on the tube sheet 3 on the downstream side in the flow direction of the first fluid F1, and a discharge portion 30 is provided on the tube sheet 3 on the upstream side in the flow direction of the first fluid F1. Furthermore, at the end of each elbow portion 12 closer to the piping body 11 than the tube sheet 3, a plurality of communication holes 13 are provided that penetrate the elbow portion 12 in the circumferential direction of the elbow portion 12.

[0014] (vane) Each vane 2 is curved along the curve of the elbow portion 12. A plurality of such vanes 2 are provided at intervals in a direction intersecting the direction in which the elbow portion 12 extends.

[0015] (tube sheet) The tube sheets 3 are provided one at each end in the extension direction of the piping body 11. A pair of tube sheets 3 are provided at intervals in the extension direction of the flow path P so as to close the flow path P, thereby defining a closed space V in part of the flow path P within the piping 10. The pair of tube sheets 3 are penetrated by a plurality of heat transfer tubes 4 arranged in the piping body 11.

[0016] (heat transfer tube) The heat transfer tubes 4 are tubular with both ends open, extend through the pair of tube plates 3, and are provided in plurality, spaced apart from one another. Because the heat transfer tubes 4 communicate with the elbow portions 12, the interiors of the heat transfer tubes 4 form first flow paths P1 through which the first fluid F1 flows. The heat transfer tubes 4 extend parallel to one another. Hereinafter, the axial direction Da of the heat transfer tube 4 may be simply referred to as the axial direction Da, and the circumferential direction of the heat transfer tube 4 may be simply referred to as the circumferential direction.

[0017] Furthermore, the heat transfer tubes 4 are formed in a polygonal shape when viewed from the axial direction Da. In this embodiment, the heat transfer tubes 4 are formed in a hexagonal shape when viewed from the axial direction Da. The multiple heat transfer tubes 4 are adjacent to each other so that their outer surfaces are parallel to each other, and are arranged in a honeycomb shape as a whole. Furthermore, between the outermost heat transfer tubes 4 among the multiple heat transfer tubes 4 and the piping main body 11, there is provided a gap that is approximately the same as the gap between the heat transfer tubes 4. The spaces formed between the heat transfer tubes 4 and the space formed between the heat transfer tubes 4 and the piping main body 11 of the piping 10 form second flow paths P2 through which the second fluid F2 flows. This second flow path P2 extends parallel to the first flow path P1. The second flow path P2 is provided with a partition member 40, which will be described later.

[0018] (Supply Department) The supply unit 20 is provided on the tube sheet 3 downstream in the flow direction of the first fluid F1. The supply unit 20 communicates with the closed space V in the piping 10 via a communication hole 13. The supply unit 20 is provided as a so-called inlet header that enables the second fluid F2 to be supplied into the closed space V from outside the piping 10.

[0019] As shown in FIG. 3 , the supply section 20 includes a cylindrical supply section main body 21 that covers the end of the elbow section 12 from the outside and a supply-side bottom plate 22 that closes the opening of the supply section main body 21 on the upstream side in the flow direction of the first fluid F1. The opening of the supply section main body 21 on the downstream side in the flow direction of the first fluid F1 is closed by a tube plate 3. A supply opening 23 for supplying the second fluid F2 from the outside is formed in a portion of the circumferential direction of the supply section main body 21. The supply-side bottom plate 22 is provided at the boundary between the elbow section 12 and the piping main body 11 and is formed to protrude radially outward from the piping main body 11. The supply-side bottom plate 22 is penetrated by a heat transfer tube 4. The supply-side bottom plate 22, together with the elbow section 12, the supply section main body 21, and the tube plate 3, forms a space within the supply section 20 into which the second fluid F2 is supplied. This space is connected to the second flow path P2 within the closed space V via a communication hole 13.

[0020] (Discharge section) Returning to Fig. 2, the discharge section 30 is provided on the tube sheet 3 on the upstream side in the flow direction of the first fluid F1. The discharge section 30 communicates with the closed space V in the piping 10 via a communication hole 13. The discharge section 30 is provided as a so-called outlet-side header that enables the second fluid F2 in the closed space V to be discharged to the outside of the piping 10.

[0021] The discharge unit 30 and the supply unit 20 have the same configuration except for the direction of fluid flow. That is, the discharge unit 30 has a discharge unit main body 31 corresponding to the supply unit main body 21 and a discharge-side bottom plate 32 corresponding to the supply-side bottom plate 22.

[0022] The discharge section main body 31 is formed in a cylindrical shape that covers the end of the elbow section 12 from the outside, and the opening on the upstream side in the flow direction of the discharge section main body 31 is closed by the tube plate 3. A discharge opening 33 for discharging the second fluid F2 to the outside is formed in a portion of the circumferential direction of the discharge section main body 31. The discharge side bottom plate 32 closes the opening of the discharge section main body 31 on the downstream side in the flow direction of the first fluid F1. The discharge side bottom plate 32 is provided at the boundary between the elbow section 12 and the piping main body 11 and is formed to protrude radially outward from the piping main body 11. The discharge side bottom plate 32 is penetrated by the heat transfer tube 4. The discharge side bottom plate 32, together with the elbow section 12, the discharge section main body 31, and the tube plate 3, forms a space within the discharge section 30 into which the second fluid F2 is supplied. This space is connected to the second flow path P2 via the communication hole 13.

[0023] In this embodiment, the supply section 20 is arranged downstream in the flow direction of the first fluid F1, and the discharge section 30 is arranged upstream in the flow direction of the first fluid F1, so that the second fluid F2 flows in the opposite direction to the first fluid F1 in the axial direction Da.

[0024] (Partition material) The partition member 40 is provided within the closed space V. The partition member 40 divides the flow path (second flow path P2) around the heat transfer tube 4 into a plurality of small flow paths Ps that extend in the axial direction Da of the heat transfer tube 4 and are divided in the circumferential direction. The partition members 40 are provided between adjacent heat transfer tubes 4 and between the heat transfer tube 4 and the piping main body 11 of the piping 10. More specifically, the partition members 40 are provided at the corners of the heat transfer tube 4 when viewed from the axial direction Da.

[0025] (Small channel) Within the small flow passage Ps, a rib row 50 having a plurality of ribs 51 arranged at intervals in the axial direction Da of the heat transfer tube 4 is provided. In the following, for one small flow path Ps, the direction perpendicular to the axial direction Da and along the circumferential direction will be referred to as the width direction W (of the small flow path Ps), and the direction perpendicular to the axial direction Da and the width direction W will be referred to as the thickness direction (of the small flow path Ps).

[0026] (Rib row) The rib rows 50 are provided in all the small flow paths Ps partitioned by the partition member 40. The rib rows 50 are provided in a plurality of rows spaced apart in the circumferential direction in the small flow path Ps. In this embodiment, two rib rows 50 are provided in one small flow path Ps. The two rib rows 50 are arranged equidistant from the inner surface of the small flow passage Ps in the width direction W. In each rib row 50, the ribs 51 are arranged equidistantly in the axial direction Da. In each pair of two circumferentially adjacent rib rows 50, the ribs 51 are arranged in a zigzag pattern in the axial direction Da so as to be staggered in the axial direction Da.

[0027] (rib) The ribs 51 are all formed in the same shape and are cubic. The ribs 51 extend from the outer peripheral surface of the heat transfer tube 4 in the thickness direction of the small flow passage Ps. The ribs 51 connect a pair of inner surfaces that face each other in the thickness direction of the second flow passage P2. In this embodiment, the ribs 51 are arranged so that the pitch L1 of the ribs 51 in the axial direction Da is longer than the pitch L2 of the ribs 51 in the width direction W. In addition, from the viewpoint of preventing clogging, it is desirable that the distance between the ribs 51 and the distance between the outer surface of the rib 51 and the inner surface of the second flow passage P2 be, for example, 1 mm or more. Moreover, it is desirable that the area of ​​the small flow passages Ps that is blocked by the ribs 51 is less than one-third in the width direction W. The above-mentioned ribs 51 and partition members 40 are preferably formed integrally with the heat transfer tubes 4 by 3D printer technology, such as additive manufacturing (AM). It is also preferable that the above-mentioned components constituting the heat exchanger 1 other than the ribs 51, partition members 40, and heat transfer tubes 4 are manufactured in the same manner.

[0028] (Action and effect) According to the heat exchanger 1 of this embodiment, the following effects are achieved. In this embodiment, the heat exchanger 1 includes a pipe 10 that forms a flow path P to which a first fluid F1 is supplied, a pair of tube plates 3 that are arranged at intervals in the extension direction of the flow path P so as to block the flow path P, thereby forming a closed space V in part of the flow path P, a plurality of heat transfer tubes 4 that are tubular and open at both ends, extend to penetrate the pair of tube plates 3, and are arranged side by side at intervals from each other, a supply section 20 that can supply a second fluid F2 from outside the pipe 10 into the closed space V, a discharge section 30 that can discharge the second fluid F2 in the closed space V to the outside of the pipe 10, a partition member 40 that divides the flow path around the heat transfer tube 4 (second flow path P2) into a plurality of small flow paths Ps that extend in the axial direction Da of the heat transfer tube 4 and are divided circumferentially, and a rib row 50 that is provided in the small flow path Ps and has a plurality of ribs 51 arranged at intervals in the axial direction Da of the heat transfer tube 4.

[0029] This allows the second fluid F2 to flow linearly in the axial direction Da within the small passages Ps. This prevents the second fluid F2 from being mixed in a complex manner in the circumferential direction, and prevents heat from being unevenly distributed around the heat transfer tube 4. Furthermore, the second fluid F2 collides with the ribs 51 within the small passages Ps, which moderately disturbs the flow within the small passages Ps and allows the second fluid F2 to be mixed appropriately. This prevents the development of a boundary layer. This improves the heat transfer coefficient within the small passages Ps. This allows efficient heat exchange between the first fluid F1 and the second fluid F2, improving heat exchange performance.

[0030] In particular, when multiple heat transfer tubes 4 are arranged horizontally, the second fluid F2 moves due to natural convection, which prevents heat from being unevenly distributed in the vertical direction, and the effect of improving heat exchange performance is more effectively achieved. Furthermore, even if the flow of the second fluid F2 is prone to bias due to manufacturing errors, movement of the second fluid F2 in a direction intersecting the axial direction Da is suppressed, thereby suppressing heat bias and improving heat exchange performance.

[0031] In this embodiment, the rib rows 50 are arranged in multiple rows spaced apart circumferentially in the small flow path Ps, and in a pair of two circumferentially adjacent rib rows 50, the ribs 51 are arranged in a zigzag pattern in the axial direction Da so that they are staggered in the axial direction Da.

[0032] As a result, the second fluid F2 flows in a meandering manner between the ribs 51. This more effectively suppresses the development of a boundary layer, further improving the heat transfer coefficient in the small passages Ps. This therefore more efficiently carries out heat exchange between the first fluid F1 and the second fluid F2, further improving the heat exchange performance.

[0033] In this embodiment, the partition members 40 are provided between adjacent heat transfer tubes 4 and between the heat transfer tube 4 and the piping 10.

[0034] As a result, small flow paths Ps are formed evenly between the heat transfer tubes 4 and between the heat transfer tubes 4 and the piping 10. This further prevents the second fluid F2 from being mixed in a complex manner in the circumferential direction, and further prevents uneven distribution of heat around the heat transfer tubes 4. This therefore makes heat exchange between the first fluid F1 and the second fluid F2 more efficient, further improving heat exchange performance.

[0035] In this embodiment, the heat transfer tubes 4 are formed in a polygonal shape when viewed from the axial direction Da, and the partition members 40 are provided at the corners of the heat transfer tubes 4 when viewed from the axial direction Da.

[0036] This forms the small passages Ps in the shape of a uniform flat plate extending in the axial direction Da, stabilizing the flow of the second fluid F2 in the small passages Ps. This further suppresses uneven distribution of heat in the small passages Ps. This further improves heat exchange efficiency between the first fluid F1 and the second fluid F2, further improving heat exchange performance.

[0037] In this embodiment, the ribs 51 connect a pair of inner surfaces facing each other in the thickness direction of the small flow passages Ps.

[0038] This makes it possible to prevent the outer shell of the second flow passage P2 from being deformed by the flow pressure in the heat exchanger 1. Therefore, the strength of the second flow passage P2 portion of the heat exchanger 1 is improved.

[0039] (Modification of the first embodiment) Next, a modified example of the first embodiment will be described with reference to FIG. As shown in Fig. 5, three or more rib rows 50 may be provided in the small flow path Ps. Fig. 5 illustrates a case where three rib rows 50 are provided. In this case, the ribs 51 are arranged so that they are adjacent to each other in the width direction W, with the ribs 51 spaced apart from each other.

[0040] Second Embodiment A heat exchanger 201 according to a second embodiment of the present disclosure will be described below with reference to Figures 6 and 7. Configurations similar to those in the first embodiment will be given the same names and reference numerals as in the first embodiment, and descriptions thereof will be omitted as appropriate. 6 and 7, the rib 251 is circular when viewed in the thickness direction of the small flow passage Ps, and is formed in a hand drum shape extending in the thickness direction of the small flow passage Ps. In other words, the rib 251 is formed in a cylindrical shape extending from the outer peripheral surface of the heat transfer tube 4, and is formed so as to curve and gradually taper from both ends in the extension direction (both ends in the thickness direction) to the middle part in the extension direction (middle part in the thickness direction). Therefore, both ends of the rib 251 are smoothly connected to a pair of inner surfaces facing each other in the thickness direction of the small flow passage Ps.

[0041] The heat exchanger 201 also includes an orifice plate 60 at the upstream end (supply unit 20 side) of each small flow path Ps. That is, the orifice plate 60 is provided upstream of the rib row 250. A plurality of orifice plates 60 are provided for each small flow path Ps. Note that only one orifice plate 60 may be provided for each small flow path Ps. The orifice plate 60 is provided with an orifice hole 61 penetrating in the axial direction Da. The second fluid F2 supplied from the supply unit 20 first passes through the orifice hole 61 and then flows between the ribs 51. The orifice holes 61 of the orifice plates 60 adjacent to each other in the axial direction Da are arranged so as not to overlap in the axial direction Da.

[0042] (Action and effect) According to the heat exchanger 201 of this embodiment, the following effects are achieved. In this embodiment, the rib 251 may be formed in a cylindrical shape extending from the outer peripheral surface of the heat transfer tube 4, and may be formed so as to curve and gradually taper from both ends in the extension direction toward the middle part in the extension direction.

[0043] This reduces stress concentration on the surface of the rib 251 and at the connection points between the rib 251 and the small flow passage Ps compared to when the rib 251 is formed in a polygonal shape. This improves the strength around the small flow passage Ps. Furthermore, the second fluid F2 can flow smoothly along the surface of the rib 251 and at the connection points between the rib 251 and the small flow passage Ps. This reduces pressure loss of the second fluid F2. While reducing pressure loss in this way, the rib 251 can also improve the heat transfer coefficient by suppressing the development of a boundary layer. This makes it possible to simultaneously achieve low pressure loss, high heat exchange performance, and high strength.

[0044] In this embodiment, the heat exchanger 201 includes an orifice plate 60 at the upstream end of each small flow path Ps. The orifice plate 60 is provided with orifice holes 61 that penetrate in the axial direction Da.

[0045] The resistance experienced by the second fluid F2 can be adjusted by adjusting the number of orifice plates 60 and the density of the orifice holes 61. For example, by decreasing the number of orifice plates 60 and the density of the orifice holes 61 from the outer periphery toward the inner periphery, the resistance experienced by the second fluid F2 before reaching each small passage Ps can be adjusted. Therefore, the flow velocity in each small passage Ps can be made uniform, which suppresses uneven heat distribution and further improves heat exchange performance.

[0046] (Other embodiments) The above describes in detail the embodiments of the present disclosure with reference to the drawings, but the specific configuration is not limited to this embodiment, and design changes and the like are also included within the scope that does not deviate from the gist of the present disclosure.

[0047] In the above embodiment, the pipe 10 has elbow portions 12 at the inlets and outlets on both ends of the pipe main body 11, but this is not limited to this. The pipes provided on both ends of the pipe main body 11 are not limited to elbow portions 12 and can be changed as appropriate. For example, the elbow portions 12 may be straight pipes. Furthermore, pipes corresponding to elbow portions 12 do not necessarily have to be provided at both ends of the pipe body 11. In this case, for example, as shown in FIG. 8 (a drawing corresponding to FIG. 4 of the first embodiment), the inner circumferential surface of the supply body 21 of the supply part 20 is molded so as to cover the outer shape of the bundle of the heat transfer tubes 4. Although not shown, the discharge body 31 of the discharge part 30 is also molded in the same manner as the supply body 21. In other words, the inner circumferential surface of the discharge body 31 is molded so as to cover the outer shape of the bundle of the heat transfer tubes 4.

[0048] In the above embodiment, the first fluid F1 is exemplified by high-temperature exhaust gas discharged from a heat engine such as an engine, but is not limited thereto. The first fluid F1 may be a fluid other than exhaust gas, such as water, oil, fuel, or an organic liquid such as Fluorinert.

[0049] In the above embodiment, the second fluid F2 is water, but this is not limiting, and the second fluid F2 may be, for example, oil, fuel, or an organic liquid such as Fluorinert.

[0050] In the above embodiment, the heat exchangers 1 and 201 are used to cool the first fluid F1, but this is not limiting. The heat exchangers 1 and 201 may also be used to heat the first fluid F1.

[0051] In the above embodiment, the heat transfer tubes 4 are formed in a hexagonal shape when viewed from the axial direction Da, but this is not limited thereto. The heat transfer tubes 4 may be formed in a polygonal shape other than a hexagonal shape.

[0052] In the above embodiment, the second fluid F2 flows in the opposite direction to the first fluid F1 in the axial direction Da, but this is not limited thereto. The supply unit 20 and the discharge unit 30 may be arranged so that the second fluid F2 flows in the same direction as the first fluid F1 in the axial direction Da.

[0053] In the above embodiment, the rib rows 50, 250 are provided in all of the small flow paths Ps partitioned by the partition member 40, but this is not limited to this. The rib rows 50, 250 may be provided in only some of the small flow paths Ps.

[0054] In the above embodiment, the rib rows 50, 250 are provided in a plurality of rows spaced apart in the circumferential direction in the small flow passage Ps, but this is not limited thereto. Only one rib row 50, 250 may be provided in the small flow passage Ps.

[0055] In the above embodiment, the ribs 51, 251 are all formed in the same shape, but this is not limited to this. The ribs 51, 251 may be formed in different shapes, and the shapes of the ribs 51, 251 can be changed as appropriate.

[0056] In the above embodiment, a plurality of orifice plates 60 are provided for each small flow path Ps, but this is not limitative. Only one orifice plate 60 may be provided for each small flow path Ps.

[0057] <Additional Notes> The heat exchangers 1 and 201 described in the respective embodiments can be understood, for example, as follows.

[0058] (1) A heat exchanger 1, 201 according to a first aspect includes a pipe 10 forming a flow path P to which a first fluid F1 is supplied, a pair of tube plates 3 arranged at intervals in the extending direction of the flow path P so as to close the flow path P, thereby defining a closed space V in a part of the flow path P, a plurality of heat transfer tubes 4 formed in a tubular shape with both ends open and extending to penetrate the pair of tube plates 3 and arranged side by side at intervals from each other, and a heat transfer tube 4 extending from the outside of the pipe 10 into the closed space V. The system includes a supply section 20 capable of supplying a second fluid F2, a discharge section 30 capable of discharging the second fluid F2 in the closed space V to the outside of the piping 10, a partition member 40 that divides the flow path around the heat transfer tube 4 into a plurality of small flow paths Ps that extend in the axial direction Da of the heat transfer tube 4 and are divided circumferentially, and a rib row 50, 250 that is provided in the small flow paths Ps and has a plurality of ribs 51, 251 arranged at intervals in the axial direction Da of the heat transfer tube 4.

[0059] This allows the second fluid F2 to flow linearly in the axial direction Da within the small passages Ps. This prevents the second fluid F2 from being mixed in a complex manner in the circumferential direction, thereby preventing heat unevenness around the heat transfer tube 4. Furthermore, the second fluid F2 collides with the ribs 51, 251 within the small passages Ps, which moderately disturbs the flow within the small passages Ps and allows the second fluid F2 to be mixed appropriately. This prevents the development of a boundary layer. This improves the heat transfer coefficient within the small passages Ps.

[0060] (2) The heat exchanger 1, 201 of the second aspect is the heat exchanger 1, 201 of (1), wherein the rib rows 50 are provided in multiple rows spaced apart in the circumferential direction in the small flow path Ps, and in a pair of two rib rows 50, 250 adjacent in the circumferential direction, the ribs 51, 251 may be arranged in a zigzag pattern in the axial direction Da so as to be staggered in the axial direction Da.

[0061] As a result, the second fluid F2 flows in a meandering manner between the ribs 51, 251. This further effectively suppresses the development of a boundary layer, and further improves the heat transfer coefficient in the small passages Ps.

[0062] (3) The heat exchanger 201 of the third aspect is the heat exchanger 201 of (1) or (2), wherein the ribs 51 are formed in a cylindrical shape extending from the outer peripheral surface of the heat transfer tube 4, and may be formed so as to be curved and gradually tapered from both ends in the extension direction toward the middle part in the extension direction.

[0063] This reduces stress concentration on the surface of the rib 251 and at the connection points between the rib 251 and the small flow passage Ps compared to when the rib 251 is formed in a polygonal shape. Furthermore, the second fluid F2 can flow smoothly on the surface of the rib 251 and at the connection points between the rib 251 and the small flow passage Ps. This reduces pressure loss of the second fluid F2.

[0064] (4) The heat exchanger 1, 201 of the fourth aspect is the heat exchanger 1, 201 of any one of (1) to (3), and the partition member 40 may be provided between adjacent heat transfer tubes 4 and between the heat transfer tube 4 and the piping 10.

[0065] As a result, small flow paths Ps are formed evenly between the heat transfer tubes 4 and between the heat transfer tubes 4 and the piping 10. This further prevents the second fluid F2 from being mixed in a complex manner in the circumferential direction, and further prevents heat from being distributed unevenly around the heat transfer tubes 4.

[0066] (5) The heat exchanger 1, 201 of the fifth aspect is the heat exchanger 1, 201 of any one of (1) to (4), wherein the heat transfer tube 4 is formed in a polygonal shape when viewed from the axial direction Da, and the partition member 40 may be provided at a corner of the heat transfer tube 4 when viewed from the axial direction Da.

[0067] This forms the small passages Ps in the shape of a uniform flat plate extending in the axial direction Da, stabilizing the flow of the second fluid F2 in the small passages Ps, thereby further suppressing uneven distribution of heat in the small passages Ps. [Explanation of symbols]

[0068] DESCRIPTION OF SYMBOLS 1...heat exchanger 2...vane 3...tube plate 4...heat transfer tube 10...piping 11...piping body 12...elbow section 13...communicating hole 20...supply section 21...supply section body 22...supply side bottom plate 23...supply opening 30...discharge section 31...discharge section body 32...discharge side bottom plate 33...discharge opening 40...partition member 50...rib row 51...rib 60...orifice plate 61...orifice hole 201...heat exchanger 250...rib row 251...rib Da...axial direction F1...first fluid F2...second fluid L1...pitch L2...pitch P...flow path P1...first flow path P2...second flow path Ps...small flow path V...closed space W...width direction

Claims

1. a pipe forming a flow path to which a first fluid is supplied; a pair of tube sheets arranged at an interval in the extension direction of the flow path so as to close the flow path, thereby defining a closed space in a part of the flow path; a plurality of heat transfer tubes each having a tubular shape with both ends open, extending to penetrate the pair of tube plates, and arranged side by side at intervals; a supply unit capable of supplying a second fluid into the closed space from outside the piping; a discharge part capable of discharging the second fluid in the closed space to the outside of the piping; a partition member that divides the flow path around the heat transfer tube into a plurality of small flow paths that extend in the axial direction of the heat transfer tube and are divided in the circumferential direction; a rib row provided in the small flow path and having a plurality of ribs arranged at intervals in the axial direction of the heat transfer tube; A heat exchanger comprising:

2. The rib row is provided in a plurality of rows at intervals in the circumferential direction in the small flow path, The heat exchanger according to claim 1 , wherein in each set of two circumferentially adjacent rib rows, the ribs are arranged in a zigzag pattern in the axial direction so as to be alternately arranged in the axial direction.

3. 3. The heat exchanger according to claim 1, wherein the ribs are formed in a cylindrical shape extending from the outer peripheral surface of the heat transfer tube, and are curved and gradually tapered from both ends in the extension direction toward the intermediate portion in the extension direction.

4. The heat exchanger according to claim 1 or 2, wherein the partition members are provided between adjacent ones of the heat transfer tubes and between the heat transfer tubes and the piping.

5. The heat transfer tube is formed in a polygonal shape when viewed in the axial direction, The heat exchanger according to claim 1 or 2, wherein the partition members are provided at corners of the heat transfer tubes when viewed in the axial direction.

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