Heat exchanger and water heating device comprising same

Abstract

The invention provides a heat exchanger and a warm water device which can appropriately eliminate the possibility that hot water boils in the upstream end part of a flat or elliptical heat transfer pipe in the flow direction of heating gas. A baffle plate disposed in a flat or elliptical heat transfer tube of a heat exchanger comprises: a plurality of first protruding pieces capable of guiding traveling hot water so as to flow on the upstream side of the heat transfer tube in the flow direction of a heating gas, i.e., in the vicinity of the upstream-side end of the heat transfer tube, and a plurality of second protruding pieces capable of guiding the traveling hot water in the vicinity of the upstream-side end of the heat transfer tube in the flow direction of the heating gas; the plurality of second protruding pieces are located closer to the heating upstream side end than the plurality of first protruding pieces, and a plurality of first gaps are formed between the plurality of second protruding pieces and the inner wall surface of the heating upstream side end, and a plurality of second gaps are formed between the plurality of second protruding pieces. The hot water guided by the plurality of first protruding pieces flows in / out.

Description

TECHNICAL FIELD

[0001] The present application relates to a heat exchanger and a hot water supply device such as a hot water device including the same. BACKGROUND

[0002] As a heat exchanger constituting a hot water device, for example, there is a heat exchanger of a structure in which a baffle is arranged in a heat transfer pipe (for example, refer to Patent Documents 1 to 4).

[0003] The heat transfer pipe is provided in a shell that supplies a heating gas such as combustion gas, and hot water as a heating target is supplied into the heat transfer pipe. The baffle is a member for generating turbulent flow of the hot water in the heat transfer pipe, and contributes to improvement of heat exchange efficiency.

[0004] However, in the related art, there is still room for improvement as described below.

[0005] That is, as the heat transfer pipe, there are cases where a flat or elliptical heat transfer pipe whose longitudinal width is larger than the lateral width is used, and one end portion side of the longitudinal width direction of the heat transfer pipe becomes a heating upstream side end portion that is an upstream side in the flow direction of the heating gas. In this case, since the heating upstream side end portion of the heat transfer pipe is heated to a high temperature, local boiling of the hot water is likely to occur in the inside. The boiling of the hot water generates bubbles in the heat transfer pipe, and a so-called partial dryout state is generated, which leads to breakage of the heat transfer pipe, a large reduction in heat exchange efficiency, and the like, and thus it is desirable to avoid such a situation as much as possible.

[0006] On the contrary, in the related art, only the turbulent flow can be generated in the vicinity of the center in the heat transfer pipe, or only the flow of the hot water from one end portion of the longitudinal width direction of the heat transfer pipe toward the other end portion side can be generated. That is, it is difficult to effectively generate the turbulent flow of the hot water in the heating upstream side end portion of the heat transfer pipe. As a result, there is a possibility that the hot water boils in the heating upstream side end portion of the heat transfer pipe, and there is room for improvement in this regard.

[0007] [Related Art Documents]

[0008] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Laid-Open No. 47-015743

[0010] [Patent Document 2] Japanese Patent No. 6357480

[0011] [Patent Document 3] Japanese Patent Laid-Open No. 2019-510952

[0012] [Patent Document 4] Japanese Patent Laid-Open No. 2018-100790 SUMMARY

[0013] [Problems to be solved by the invention]

[0014] The present invention has been made in the light of the circumstances, and aims to provide a heat exchanger capable of appropriately eliminating the possibility of generation of hot water boiling in an end portion on an upstream side in a heating gas flow direction of a heat transfer tube in a case where the heat transfer tube is flat or elliptical, and a hot water device including the heat exchanger.

[0015] [Technical means for solving the problems]

[0016] To solve the problems, in the present invention, the following technical means are adopted.

[0017] The heat exchanger provided by the first aspect of the present invention includes a heat transfer tube provided in a shell that supplies a heating gas, and that supplies hot water as a heating target to the inside, and that is flat or elliptical with a longitudinal width larger than a lateral width, and a baffle provided in the heat transfer tube, the baffle including a baffle main body portion extending in a length direction x of the heat transfer tube, and a plurality of protruding piece portions protruding from the baffle main body portion in a lateral width direction y of the heat transfer tube, and the heating gas flowing in a longitudinal width direction z of the heat transfer tube, the heat exchanger characterized in that, as the plurality of protruding piece portions, a plurality of first protruding piece portions each provided in a configuration spaced apart in the length direction x, and a plurality of second protruding piece portions each provided in a configuration spaced apart in the length direction x, are included, the plurality of first protruding piece portions being able to guide hot water traveling toward the plurality of first protruding piece portions in a manner flowing in the vicinity of an end portion on an upstream side in a heating gas flow direction of the heat transfer tube, i.e., a heating upstream side end portion, the plurality of second protruding piece portions being located closer to the vicinity of the heating upstream side end portion than the plurality of first protruding piece portions, a plurality of first gaps being formed between the plurality of second protruding piece portions and an inner wall surface of the heating upstream side end portion, and a plurality of second gaps being formed between the plurality of second protruding piece portions, configured to be able to flow in / out of the plurality of first and second gaps the hot water guided to the vicinity of the heating upstream side end portion by the plurality of first protruding piece portions.

[0018] According to this structure, the following effects can be obtained.

[0019] That is, hot water flowing into the heat transfer pipe is guided to flow in the vicinity of the heating-upstream side end portion of the heat transfer pipe when reaching a portion provided with the first protruding piece portion. Then, a part of the hot water flows into the first gap between the second protruding piece portion and the inner wall surface of the heating-upstream side end portion of the heat transfer pipe through the second gaps between the plurality of second protruding piece portions and the like. In addition, the hot water flowing into the first gap in this manner flows out to the outside of the first gap through the other second gaps and the like. In each portion provided with the plurality of first protruding piece portions and the second protruding piece portions, the hot water actively flows into / out of the first gap or the second gap in this manner, whereby turbulent flow of the hot water is sufficiently and effectively generated in the heating-upstream side end portion of the heat transfer pipe. As a result, the hot water is prevented from boiling in the heating-upstream side end portion of the heat transfer pipe in which the hot water is heated to a relatively high temperature by the heating gas, and adverse conditions such as heat damage of the heat transfer pipe are appropriately prevented, and the heat exchange efficiency is improved.

[0020] The present application further exhibits effects in the case where the material of the heat transfer pipe is a material having a low thermal conductivity such as stainless steel.

[0021] In the present application, it is preferable that the baffle main portion be configured using a metal plate, the plurality of first protruding piece portions be cut-up portions of the metal plate, and the plurality of second protruding piece portions be portions in which one side edge portion of the metal plate is bent.

[0022] According to this structure, the baffle can be easily and reliably manufactured by performing press working on the metal plate, and reduction in manufacturing cost is achieved, which is preferable in this respect.

[0023] In the present application, it is preferable that the plurality of first protruding piece portions have a guide surface inclined toward the upstream side of the hot water flow direction in the vicinity of the heating-upstream side end portion on the more downstream side of the hot water flow direction in the heat transfer pipe.

[0024] According to this structure, the hot water flowing in the heat transfer pipe can be efficiently guided to flow in the vicinity of the heating-upstream side end portion of the heat transfer pipe by the plurality of first protruding piece portions.

[0025] In the present application, it is preferable that the plurality of second protruding piece portions include a plurality of second-1 protruding piece portions arranged to overlap the plurality of first protruding piece portions in the length direction x and protrude from the baffle main portion toward a direction opposite to the direction in which the plurality of first protruding piece portions protrude in the transverse width direction y.

[0026] According to this structure, the hot water flowing into the heating-upstream side end portion of the heat transfer pipe by the guiding action of the plurality of first protruding piece portions flows along the inner wall surface of the heating-upstream side end portion, collides with the second-1 protruding piece portion in the middle of the flow, and becomes a vortex-like flow (described later).Figure 3 the flow indicated by the arrow Nd of (b)). This is further preferable in terms of promoting the turbulent flow of the hot water.

[0027] In the present application, it is preferable that, as the plurality of second protruding piece portions, instead of the plurality of second-1 protruding piece portions or in addition to the plurality of second-1 protruding piece portions, a plurality of second-2 protruding piece portions be included, the plurality of second-2 protruding piece portions being arranged so as not to overlap with the plurality of first protruding piece portions in the length direction x and protruding in the same direction as the plurality of first protruding piece portions protrude from the baffle main body portion in the lateral width direction y.

[0028] According to this structure, the turbulent flow of the hot water flowing into / out of the first gap between the plurality of second-1 protruding piece portions and the inner wall surface of the heating upstream side end portion of the heat transfer tube, etc. can be appropriately achieved by the guiding action of the plurality of first protruding piece portions.

[0029] In the present application, it is preferable that the plurality of first protruding piece portions be provided on one side of the lateral width direction y of the baffle main body portion and a plurality of front-rear reversal protruding piece portions be provided on the opposite side, the plurality of front-rear reversal protruding piece portions being portions that correspond to the plurality of first protruding piece portions in the case of reversing the baffle in a manner that switches the front and the rear of the length direction x of the baffle.

[0030] According to this structure, in the case of assembling the heat exchanger by inserting the baffle into the heat transfer tube, the insertion direction (the front and the rear of the length direction x) of the baffle into the heat transfer tube can be disregarded. Thus, the ease of the assembly work of the heat exchanger can be achieved. In addition, an assembly error of confusing the insertion direction of the baffle can be avoided. Furthermore, the plurality of front-rear reversal protruding piece portions contribute to the generation of the turbulent flow of the hot water in the heat transfer tube, and the improvement of the heat exchange efficiency, and are further preferable in this respect.

[0031] In the present application, it is preferable that the baffle further include a plurality of up-down reversal protruding piece portions, the plurality of up-down reversal protruding piece portions having rotational symmetry about the center line of the longitudinal width direction z of the heat transfer tube with respect to the plurality of first protruding piece portions and second protruding piece portions and the plurality of front-rear reversal protruding piece portions, the plurality of up-down reversal protruding piece portions being portions that correspond to the plurality of first protruding piece portions and second protruding piece portions and the plurality of front-rear reversal protruding piece portions in the case of reversing the baffle in the up-down direction of the longitudinal width direction z.

[0032] According to such a structure, in the case of assembling the heat exchanger by inserting the baffle into the heat transfer pipe, the upper and lower orientations of the baffle can be ignored. Therefore, the ease of the assembly work of the heat exchanger can be achieved, and the assembly error of confusing the upper and lower orientations of the baffle can also be avoided. Further, the plurality of upper and lower reversal protruding piece portions contribute to the generation of turbulent flow of hot water, and the heat exchange efficiency is improved, and is more preferable in this respect.

[0033] In the present application, it is preferable that the plurality of first protruding piece portions and second protruding piece portions, the plurality of front and rear reversal protruding piece portions, and the plurality of upper and lower reversal protruding piece portions are arranged on the upper side or the lower side of a certain region so as to avoid the certain region around the center in the longitudinal width direction z of the heat transfer pipe.

[0034] According to such a structure, hot water flowing in a certain region around the center in the longitudinal width direction z of the heat transfer pipe does not directly abut against the various plurality of protruding piece portions. Therefore, it is preferable in terms of preventing excessive flow path resistance in the heat transfer pipe. In addition, since the various plurality of protruding piece portions are arranged on the upper side or the lower side of the certain region around the center in the longitudinal width direction z of the heat transfer pipe, turbulent flow of hot water is generated at both end portions (including the heating upstream side end portion) in the longitudinal width direction z of the heat transfer pipe, and the efficiency is further improved in this respect.

[0035] The hot water device provided by the second aspect of the present application includes: a heating gas supply mechanism; and a heat exchanger that heats hot water by heat recovery from heating gas supplied by the heating gas supply mechanism, and is characterized in that, as the heat exchanger, the heat exchanger provided by the first aspect of the present application is included.

[0036] By such a structure, the same effects as those described for the heat exchanger provided by the first aspect of the present application can be obtained.

[0037] Other features and advantages of the present application will become more apparent from the following description of the embodiments of the present application with reference to the attached drawings. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 is a plan cross-sectional view showing an example of the heat exchanger of the present application.

[0039] Figure 2 (a) of is a plan cross-sectional view showing an example of the heat exchanger of the present application. Figure 1 is a cross-sectional view showing an example of the overall structure of the hot water device of the heat exchanger shown in Figure 1 IIa-IIa cross-sectional view of Figure 2 (b) of is a plan cross-sectional view showing an example of the heat exchanger of the present application. Figure 2 is a plan cross-sectional view showing an example of the heat exchanger of the present application.

[0040] Figure 3(a) is Figure 1 Sectional view of IIIa-IIIa (fins omitted). Figure 3 (b) is Figure 3 (a) Magnified cross section of IIIb-IIIb.

[0041] Figure 4 (a) is Figures 1 to 3 (b) is a perspective view of the baffle of the heat exchanger. Figure 4 (b) is Figure 4 Partially omitted front view of (a), Figure 4 (c) is Figure 4 Plan view of (b), Figure 4 (d) is Figure 4 (b) Side view, Figure 4 (e) is Figure 4 (b) IVe-IVe cross section, Figure 4 (f) is Figure 4 (b) IVf-IVf cross section.

[0042] Figure 5 This is a cross-sectional view of the main parts of another embodiment of the present invention.

[0043] Figure 6 This is a cross-sectional view of the main parts of another embodiment of the present invention.

[0044] Explanation of icon numbers

[0045] HE: Heat exchanger

[0046] WH: Warm water device

[0047] B, Ba: baffle

[0048] 1: Burner (Heating gas supply mechanism)

[0049] 2: Shell

[0050] 3: Heat transfer pipe

[0051] 31: Heating the upstream end (heating the upstream end of the heat transfer tube)

[0052] 4: Main body of the baffle

[0053] 4a: Metal plate

[0054] 5a: First protruding part

[0055] 5b: Second protruding part (Second-1 protruding part)

[0056] 5c: Second protruding part (Second-2 protruding part)

[0057] 5d: protruding piece portion for front-rear inversion

[0058] 5a'~5d': protruding piece portions for up-down inversion

[0059] 61, 62: first and second gaps DETAILED DESCRIPTION

[0060] Hereinafter, a preferred embodiment of the present application will be specifically described with reference to the drawings.

[0061] Figure 2 (a) of FIG. 1, Figure 2 The hot water device WH shown in (b) of FIG. 1 is configured as a hot water supply device by combining the heat exchanger HE to which the present application is applied and the burner 1.

[0062] The burner 1 is, for example, a gas burner that causes a fuel gas to burn to generate combustion gas, and corresponds to an example of the heating gas supply mechanism according to the present application. The combustion gas corresponds to an example of the heating gas according to the present application.

[0063] The heat exchanger HE includes: a housing 2 having a plurality of side wall portions 20a, 20b of a substantially rectangular cylindrical shape with both upper and lower faces open; a plurality of heat transfer pipes 3 disposed in the housing 2; and a plurality of baffles B respectively disposed in the plurality of heat transfer pipes 3.

[0064] The housing 2 of the heat exchanger HE is disposed on the upper side of the burner 1, and in the housing 2, the combustion gas generated by the burner 1 is supplied from the lower side thereof toward the upper side. In the present embodiment, the combustion gas flow direction in the heat exchanger HE (corresponding to the heating gas flow direction) is toward the upper side.

[0065] Each heat transfer pipe 3 is a heat transfer pipe that is in a flat shape with a longitudinal width La larger than a lateral width Lb (see (b) of FIG. 1), the both side wall portions 30 in the lateral width direction y are in a flat plate shape, and the wall portions of both end portions 31, 32 in the longitudinal width direction z of the lower side and the upper side are in a substantially semicircular arc shape of a metal. The plurality of heat transfer pipes 3 are disposed in the housing 2 in a state of penetrating through the side wall portion 20b of the housing 2, and the whole or a large part thereof is disposed in the housing 2 and arranged in a substantially parallel manner at intervals in a direction (lateral width direction y) intersecting the length direction x of each heat transfer pipe 3 (see also (b) of FIG. 1). Figure 2 Figure 1

[0066] In the present embodiment, the length direction x and the lateral width direction y are both horizontal directions, and the longitudinal width direction z is a vertical direction (plumb direction).

[0067] ​​At both ends of the plurality of heat transfer pipes 3, a water inlet header 7a and a hot water outlet header 7b, and a plurality of heat transfer pipe connection headers 7c are provided, and hot water supplied to the water inlet port 70a of the water inlet header 7a passes through each of the plurality of heat transfer pipes 3 in order via the plurality of heat transfer pipe connection headers 7c, and finally reaches the hot water outlet header 7b. In this process, the hot water is heated by the combustion gas, and the hot water (warm water) generated by the heating is discharged from the hot water outlet port 70b of the hot water outlet header 7b to the desired hot water outlet destination.

[0068] The plurality of heat transfer pipes 3 are so-called finned tubes, and are engaged with a plurality of fins 39 of a plate type provided in the housing 2 for heat recovery in a state of being inserted through the fins 39.

[0069] Each baffle B is a member for generating turbulence of hot water flowing in each heat transfer pipe 3, and includes a baffle main body portion 4 formed by press working a metal plate 4a and extending in the length direction x of the heat transfer pipe 3. In addition, as portions connected to the baffle main body portion 4, a plurality of first protruding piece portions 5a, a plurality of second protruding piece portions 5b, 5c, a plurality of front and rear reversing protruding piece portions 5d, and a plurality of upper and lower reversing protruding piece portions 5a' to 5d' are included.

[0070] The baffle main body portion 4 is a thin-walled plate-shaped portion extending in the length direction x of each heat transfer pipe 3, forms a main portion of the baffle B, and has a full length dimension substantially the same as each heat transfer pipe 3. The longitudinal width Lc (see Figure 4 (a) of FIG. 1, Figure 4 (b) of FIG. 1) of both end portions in the length direction x of the baffle main body portion 4 is set to be substantially the same as the inner width in the longitudinal width direction z in the heat transfer pipe 3, and a large play is not generated at the positions of the both end portions when the baffle B is inserted into the heat transfer pipe 3.

[0071] As shown in Figure 3 (a) of FIG. 1, Figure 3 (b) of FIG. 1, the plurality of first protruding piece portions and the plurality of second protruding piece portions 5a to 5c are portions that, in a case where hot water flows in the heat transfer pipe 3 from the left side of the drawing toward the right side, cause the hot water to be turbulent on the heating upstream side end portion 31 side of the heat transfer pipe 3. The heating upstream side end portion 31 is an end portion on the upstream side of the combustion gas flow direction among the both end portions 31, 32 in the longitudinal width direction z of the heat transfer pipe 3.

[0072] Each first protruding piece portion 5a is a cut-up portion of the metal plate 4a constituting the baffle main body portion 4. More specifically, each first protruding piece portion 5a is a portion in which an opening portion 40a is formed in the metal plate 4a, and a side edge portion thereof is erected on one of the transverse width directions y (the upper side and the lower side in the drawing) (see Figure 3 (a) of FIG. 1 and Figure 4 (a) of FIG. 1, Figure 4 (b) of FIG. 1).

[0073] Each first protruding piece portion 5a is arranged more toward the heating upstream side end portion 31 side than the center line CL of the longitudinal width direction z of the heat transfer pipe 3 and the baffle B. Further, each first protruding piece portion 5a has a guide surface 50 that is inclined at a moderate angle a with respect to the longitudinal width direction z in such a manner that the more downstream in the hot water flow direction within the heat transfer pipe 3, the closer to the heating upstream side end portion 31, and faces the upstream side in the hot water flow direction.

[0074] Thus, as indicated by the arrow Na of (a), it is possible to guide the hot water advancing toward the first protruding piece portion 5a in such a manner as to flow on the heating upstream side end portion 31 side of the heat transfer pipe 3. The plurality of first protruding piece portions 5a are arranged at intervals in the length direction x of the heat transfer pipe 3. Figure 3

[0075] The second protruding piece portion 5b (second-1 protruding piece portion) and the second protruding piece portion 5c (second-2 protruding piece portion) are each a site where one side edge portion of the metal plate 4a that constitutes the baffle main body portion 4 is bent. In more detail, as described below.

[0076] That is, each second protruding piece portion 5b protrudes from the side edge portion on the upstream side in the combustion gas flow direction of the baffle main body portion 4 to one of the lateral width directions y (the side opposite to the first protruding piece portion 5a), and has an appropriate length Le in the length direction x. Each second protruding piece portion 5b overlaps each first protruding piece portion 5a (except for the leftmost protruding piece portion 5a) in the length direction x of the heat transfer pipe 3, and is located on the heating upstream side end portion 31 side of the heat transfer pipe 3 more than the plurality of first protruding piece portions 5a, and is arranged at intervals in the length direction x of the heat transfer pipe 3.

[0077] A first gap 61 (61b) is formed between each second protruding piece portion 5b and the inner wall surface of the heating upstream side end portion 31, and a second gap 62 (62b) is formed between each of the plurality of second protruding piece portions 5b. These first gap 61 and second gap 62 correspond to flow paths for turbulent flow of the hot water.

[0078] Each second protruding piece portion 5c, like each second protruding piece portion 5b, protrudes from the side edge portion on the upstream side in the combustion gas flow direction of the baffle main body portion 4 to the lateral width direction y, and the length Lf in the length direction x is set to be substantially the same as the length Le of the second protruding piece portion 5b. However, the protruding direction of the second protruding piece portion 5c in the lateral width direction y is set to be opposite to that of the second protruding piece portion 5b. In addition, the second protruding piece portion 5c is arranged so as to be located between the plurality of second protruding piece portions 5b in the length direction x of the heat transfer pipe 3, and not to overlap each first protruding piece portion 5a.

[0079] ​The second protruding pieces 5c, like the second protruding pieces 5b, are arranged at intervals along the longitudinal direction x of the heat transfer tube 3, and a first gap 61 (61c) is formed between these second protruding pieces 5c and the inner wall surface of the upstream end 31 of the heating tube. In addition, a second gap 62 (62c) is formed between each of the multiple second protruding pieces 5c.

[0080] like Figure 3 of (a) Figure 3 As shown by arrow Na in (b), the hot water guided from the first protruding piece 5a to the upstream end 31 of the heat transfer tube 3 can then flow into the first gap 61 and the second gap 62, as shown by arrows Nb and Nc. Additionally, as shown by arrow Nd, a portion of the hot water forms a vortex.

[0081] The multiple reversible protruding portions 5d are essentially the locations of the multiple first protruding portions 5a when the baffle B is reversed in a manner that switches its length direction x. The reversible protruding portions 5d are provided on one side of the baffle body 4 in the lateral width direction y, opposite to the first protruding portions 5a. Figure 3 (a) and Figure 4 of (a) Figure 4 (b) on the inside), and configured to have rotational symmetry (double symmetry) with respect to the first protruding piece 5a about an axis extending in the longitudinal width direction z. The front-to-back reversing protruding piece 5d adopts the same forming mechanism as the first protruding piece 5a, and is a part with an opening 40d provided on the baffle body 4 erected on one side edge.

[0082] Furthermore, the second protruding piece 5b and the second protruding piece 5c, like the first protruding piece 5a and the front-to-back reversing protruding piece 5d, have rotational symmetry about an axis extending along the longitudinal width direction z.

[0083] Multiple up-and-down reversible protruding portions 5a' to 5d' are portions that substantially become the multiple protruding portions 5a to 5d (first protruding portions and second protruding portions 5a to 5c, and forward-and-backward reversible protruding portions 5d) when the baffle B is reversed up and down. These multiple up-and-down reversible protruding portions 5a' to 5d' are provided above the center line CL in the longitudinal width direction z of the baffle body portion 4, and are configured to have rotational symmetry (double symmetry) about the center line CL with respect to the multiple protruding portions 5a to 5d. The forming mechanism of the multiple up-and-down reversible protruding portions 5a' to 5d' is the same as that of the first protruding portions and second protruding portions 5a to 5c and the forward-and-backward reversible protruding portions 5d. The symbols 40a' and 40d' indicate the openings used to form the up-and-down reversible protruding portions 5a' and 5d' as cutting portions, respectively.

[0084] The plurality of protruding fin portions 5a to 5d and the plurality of upper-and-lower-reversing protruding fin portions 5a' to 5d' are arranged so as to be positioned more on the lower side or the upper side than a certain region, so as to avoid the certain region (a region having a width Ld) in the vicinity of the center line CL in the longitudinal width direction z of the heat transfer pipes 3. This structure brings about an effect of reducing the flow resistance with respect to hot water flowing in the vicinity of the center line CL of the heat transfer pipes 3.

[0085] Next, the operation of the heat exchanger HE and the hot water device WH will be described.

[0086] First, as described above, when the hot water device WH is operated, the combustion gas generated by the burner 1 is supplied to the casing 2 of the heat exchanger HE and acts on each of the heat transfer pipes 3, and the hot water flowing in each of the heat transfer pipes 3 is heated. In this case, the heating-upstream-side end portion 31 in each of the heat transfer pipes 3 is easily heated to the highest temperature by the combustion gas, and boiling of the hot water is likely to occur as compared with other portions such as the end portion 32 on the downstream side in the flow direction of the combustion gas.

[0087] On the contrary, in the heat exchanger HE of the present embodiment, as shown in (a) of FIG. 6 and (b) of FIG. 7, a portion of the hot water flowing into each of the heat transfer pipes 3, which flows on the heating-upstream-side end portion 31 side more than the center line CL in the longitudinal width direction z, further flows on the heating-upstream-side end portion 31 side by the guiding action of each of the first protruding fin portions 5a, as indicated by an arrow Na. In addition, the hot water thereafter flows in / out through the first gap 61 and the second gap 62 formed by the plurality of second protruding fin portions 5b and 5c, as indicated by arrows Nb and Nc, thereby realizing turbulent flow of the hot water. At this time, as indicated by an arrow Nd of (b) of FIG. 7, a vortex of the hot water can also be generated in the first gap 61 and in the vicinity thereof. Figure 3 Figure 3 Figure 3

[0088] By the action, turbulent flow of the hot water is sufficiently and effectively realized in the heating-upstream-side end portion 31 of each of the heat transfer pipes 3. As a result, boiling of the hot water in the heating-upstream-side end portion 31 of each of the heat transfer pipes 3, which is heated to the highest temperature, can be avoided, and thermal damage of each of the heat transfer pipes 3 is appropriately prevented, and the heat exchange efficiency of the heat exchanger HE is improved.

[0089] In addition, the plurality of front-and-rear-reversing protruding fin portions 5d and the plurality of upper-and-lower-reversing protruding fin portions 5a' to 5d' also cause turbulent flow of the hot water. Therefore, turbulent flow of the hot water in each of the heat transfer pipes 3 is further promoted, and improvement of the heat exchange efficiency and the like is realized, and this aspect is more preferable.

[0090] ​​​The plurality of front-rear reversal protruding fin portions 5d are provided on the baffle B of the present embodiment, and even if the insertion direction (front-rear direction of the length direction x) of the baffle B into the heat transfer pipe 3 is set to be opposite to the direction shown in (a) of FIG. 10, the plurality of front-rear reversal protruding fin portions 5d substantially become the plurality of first protruding fin portions 5a, and the hot water guidance to the vicinity of the heating-upstream-side end portion 31 where the plurality of second protruding fin portions 5b, 5c are present is appropriately performed. Therefore, with the present embodiment, an assembly error of confusing the insertion direction of the baffle B does not occur, and the ease of the assembly work of the heat exchanger HE can be achieved. Figure 3

[0091] Further, the plurality of up-down reversal protruding fin portions 5a' to 5d' are provided on the baffle B, and even if the up-down direction of the baffle B is set to be opposite to the direction shown in (a) of FIG. 10 when the baffle B is inserted into the heat transfer pipe 3, the plurality of up-down reversal protruding fin portions 5a' to 5d' substantially become the plurality of first protruding fin portions and the second protruding fin portions 5a to 5c and the plurality of front-rear reversal protruding fin portions 5d. Therefore, an assembly error of confusing the up-down direction of the baffle B does not occur, and the ease of the assembly work of the heat exchanger HE can be further achieved. Figure 3

[0092] In the present embodiment, the protruding fin portions 5a' to 5c' corresponding to the first protruding fin portions and the second protruding fin portions 5a to 5c among the plurality of up-down reversal protruding fin portions 5a' to 5d' function in the same manner as the first protruding fin portions and the second protruding fin portions 5a to 5c to achieve the turbulent flow of the hot water in the end portion 32. The portion of each heat transfer pipe 3 other than the heating-upstream-side end portion 31, such as the end portion 32 on the downstream side of the combustion gas flow direction, is a portion where the combustion gas that has undergone temperature reduction by heat recovery acts, and thus the heating temperature thereof is lower when compared to the heating-upstream-side end portion 31. Therefore, the turbulent flow as described for the hot water in the heating-upstream-side end portion 31 is not originally required in the end portion 32, but even if the case where the end portion 32 is heated to a high temperature occurs, the boiling of the hot water in the end portion 32 is appropriately avoided, and the reliability of the boiling prevention is improved.

[0093] Figure 5 Figure 6 Another embodiment of the present application is shown. In the drawings, the same or similar elements as those of the embodiment are denoted by the same symbols as those of the embodiment, and repeated description is omitted.

[0094] Figure 5 The baffle Ba shown in FIG. 11 includes the plurality of first protruding fin portions 5a and the plurality of second protruding fin portions 5b (second-1 protruding fin portions) in addition to the plurality of second-2 protruding fin portions 5c.

[0095] Figure 6 ​​​The illustrated baffle Bb includes a plurality of second tab portions 5c (second-2 tab portions) in addition to the plurality of first tab portions 5a.

[0096] However, in either of the baffles Ba, Bb, none of the tab portions other than the above are included.

[0097] In either of these Figure 5 And Figure 6 In either of these

[0098] Further, it is understood from the above-described embodiment that, in the present application, a structure in which all or a part of the plurality of front-reversing tab portions 5d and the plurality of up-down reversing tab portions 5a' to 5d' are omitted can be employed.

[0099] The present application is not limited to the contents of the above-described embodiment. The specific structures of the respective portions of the heat exchanger and the hot water supply device of the present application are freely designed variously within the range desired in the present application.

[0100] The heat transfer tube targeted in the present application is a flat or elliptical heat transfer tube having a longitudinal width greater than a lateral width, and the specific ratio of the longitudinal width to the lateral width is not considered. Further, the heat transfer tube is not limited to a flat shape having a side wall portion in a flat plate shape, but can be a flat or elliptical shape having a side wall portion in a curved surface shape.

[0101] The longitudinal width direction and the lateral width direction in the present application are not limited to the up-down direction and the horizontal direction. In the above-described embodiment, the flat heat transfer tube is set in an upright posture along the up-down direction, but this is different, and for example, it can be set in a horizontal posture. In this case, the longitudinal width direction z is the horizontal direction, and the lateral width direction y becomes the up-down direction.

[0102] As the heating gas, instead of the combustion gas, for example, high-temperature exhaust gas generated in a thermal power generation system or the like can be used. The heating gas flow direction is not limited to the upward direction, but can be set in the downward direction or other directions (a burner or the like is provided on the upper side of the heat exchanger).

[0103] The hot water supply device of the present application is not limited to a general hot water supply device, but can be configured as a bathroom hot water supply device, a hot water supply device for a radiator, a hot water supply device for snow melting, or the like.

Claims

1. A heat exchanger, comprising: A heat transfer tube is installed inside a shell that supplies heating gas and supplies hot water to the interior. It is flat or elliptical with a longitudinal width greater than its transverse width. as well as A baffle is installed inside the heat transfer tube. The baffle includes: a baffle body extending along the length x of the heat transfer tube; And multiple protruding pieces, protruding from the baffle body towards the lateral width direction y of the heat transfer tube, and The heating gas flows along the longitudinal width direction z of the heat transfer tube, and the heat exchanger is characterized in that... The plurality of protruding portions include multiple first protruding portions and second protruding portions, each configured to be spaced apart in the length direction x. The plurality of first protruding plates can guide the hot water traveling toward these first protruding plates in such a way that it flows near the upstream end of the heating gas flow direction in the heat transfer tube, i.e., near the upstream end of the heating tube. The plurality of second protruding portions are located closer to the upstream end of the heating element than the plurality of first protruding portions. A plurality of first gaps are formed between the inner wall surfaces of the plurality of second protruding portions and the upstream end of the heating element, and a plurality of second gaps are formed between the plurality of second protruding portions. This configuration allows hot water guided by the plurality of first protruding portions to the vicinity of the upstream end of the heating element to flow in / out through the plurality of first gaps and second gaps.

2. The heat exchanger according to claim 1, wherein, The main body of the baffle is made of metal plate. The plurality of first protruding portions are cut-off portions of the metal plate. The plurality of second protruding portions are the curved portions of one side edge of the metal plate.

3. The heat exchanger according to claim 1, wherein, The plurality of first protruding portions have guiding surfaces that are inclined toward the upstream side of the hot water flow direction, with the guiding surfaces being closer to the downstream side of the hot water flow direction within the heat transfer tube and toward the upstream side of the heating end.

4. The heat exchanger according to claim 3, wherein, As the plurality of second protruding pieces, including a plurality of second-1 protruding pieces, These plurality of second-1 protruding portions are configured to overlap with the plurality of first protruding portions in the length direction x, and in the lateral width direction y, protrude from the baffle body portion in the direction opposite to that of the plurality of first protruding portions.

5. The heat exchanger according to claim 4, wherein, As the plurality of second protruding pieces, replacing the plurality of second-1 protruding pieces, or further including a plurality of second-2 protruding pieces. These plurality of second-2 protruding portions are configured not to overlap with the plurality of first protruding portions in the length direction x, and in the lateral width direction y, they protrude from the baffle body portion in the same direction as the plurality of first protruding portions.

6. The heat exchanger according to claim 5, wherein, The plurality of first protruding pieces are provided on one side of the transverse width direction y of the baffle body, and a plurality of forward and backward reversing protruding pieces are provided on the opposite side. The plurality of forward and backward reversing protruding pieces are the portions that correspond to the plurality of first protruding pieces when the baffle is reversed in a manner that switches the forward and backward direction x of the length of the baffle.

7. The heat exchanger according to claim 6, wherein, The baffle also includes a plurality of up-and-down reversible protruding portions, which have rotational symmetry about the center line of the longitudinal width direction z of the heat transfer tube relative to the plurality of first and second protruding portions and the plurality of front-and-back reversible protruding portions. When the baffle is reversed in the vertical direction of the longitudinal width direction z, the plurality of vertical reversing protrusions are configured to correspond to the plurality of first protrusions and second protrusions as well as the plurality of forward and backward reversing protrusions.

8. The heat exchanger according to claim 7, wherein, The plurality of first protruding pieces and second protruding pieces, the plurality of forward and backward reversing protruding pieces, and the plurality of up and down reversing protruding pieces are configured to be positioned higher or lower than a certain area, so as to avoid the certain area near the center of the longitudinal width direction z of the heat transfer tube.

9. A water warming device, comprising: Heating gas supply mechanism; as well as A heat exchanger heats hot water by recovering heat from heating gas supplied by the heating gas supply mechanism. The hot water device is characterized in that... The heat exchanger includes the heat exchanger as described in any one of claims 1 to 8.

Images