JP5710232B2 - Plate heat exchanger - Google Patents

Description

  The present invention is a plate for exchanging heat between two heat transfer plates by laminating a plurality of heat transfer plates, forming a flow path between the heat transfer plates, and flowing different kinds of fluid in adjacent flow paths. More specifically, the present invention relates to a plate heat exchanger including a heat transfer plate having a corrugated heat transfer section called a herringbone.

  A plate heat exchanger forms a flow path between stacked heat transfer plates, and heats different types of fluid through the heat transfer plates by alternately flowing different types of fluid in adjacent channels. Although it is an apparatus to exchange, the plate-type heat exchanger which improved the heat exchange efficiency is described in patent document 1. FIG.

  The plate heat exchanger includes a heat transfer plate 100 as shown in FIG. This heat transfer plate 100 is provided with passage holes 101 to 104 serving as fluid inlets and outlets at four corners of a rectangular metal plate, and a heat transfer part 110 is provided at an intermediate portion, for example, lower left and upper passage holes 101 and 102 on the left side. And the heat transfer unit 110 communicate with each other, and a gasket 120 that prevents the upper and lower passage holes 103 and 104 from opening to the heat transfer unit 110, or a gasket 120 that makes the opposite is mounted. .

  And the heat-transfer part 110 is formed in the waveform which has a herringbone-shaped protruding item | line and a concave item (it describes as a notch in patent document 1). This notch causes a strong turbulent flow and a high heat exchange coefficient (hereinafter referred to as “hard bead”) 111a, and a bead having a high flow rate and a low heat exchange coefficient (hereinafter referred to as “soft bead”). .) 111b are alternately provided from one short side A to the other short side B.

  Both the hard bead 111a and the soft bead 111b are inclined in a “C” shape or a “reverse C” shape with a center line L connecting the midpoints of the short sides A and B of the heat transfer plate 100 as symmetry axes. The hard bead 111a has an angle of 45 ° or more with respect to a line (not shown) parallel to the center line L, and the soft bead 111b has an angle of less than 45 ° with respect to a line parallel to the center line L. In addition, the pitch of the hard beads 111a is finer than the pitch of the soft beads 111b. And the length of the hard bead 111a with respect to the long sides C and D is formed as short as possible.

  Such a heat transfer plate 100 is stacked by being vertically inverted alternately in a vertically oriented vertical posture, but the hard beads 111a and soft beads 111b formed in the heat transfer section 110 intersect, and the soft beads 111b. By abutting in a state where they cross each other, the pressure strength is improved. Then, the heat transfer plates 100 that are overlapped do not cause the hard beads 111a to overlap each other, and the hard bead 111a region overlaps with the soft bead 111b region so as not to cause a large resistance in the hard bead 111a region. Yes.

Japanese Patent No. 3049450

  Although not shown, the heat transfer plate 100 is formed with a plurality of ridges and ridges inclined in an “inverted V” shape alternately in the heat transfer portion, and the folds and folds of the ridges are upstream of the fluid. Side, that is, a general herringbone type (hereinafter referred to as “vertical herringbone type”) toward the short side of the heat transfer plate 100, and a “lateral W” shape as shown in FIG. A horizontal herringbone type in which the raised ridges 131 and the recessed ridges 132 are alternately formed in the heat transfer portion, and the folded portions 133 of the ridges 131 and the recess ridges 132 are directed toward the long sides C and D of the heat transfer plate 100; There is.

  In any type of heat transfer plate 100, fluid flows along the recess 132. However, in the vertical herringbone type, since the fluid in the groove flows to the long sides C and D of the heat transfer plate 100 and does not easily return to the center line L, the fluid flows on the heat transfer section. It is difficult to uniformly disperse and it is difficult to exhibit high heat transfer performance. On the other hand, in the horizontal herringbone type, the fluid flows, for example, along the concave line 132 facing downward to the left, turns at the downstream end of the concave line 132, and then flows along the concave line 132 directed downward to the right. The heat transfer part is evenly distributed and high heat transfer performance is exhibited.

However, even in the horizontal herringbone type, with respect to the forming depth of the ridge 131 and the ridge 132 (hereinafter, mainly referred to as “depth of the ridge 132”) and a line parallel to the center line L (not shown). Depending on the angle α, high heat transfer performance may not be exhibited. For example, when the depth of the recess 132 is about 3.5 mm or more, or the angle α of the projection 131 and the recess 132 with respect to a line parallel to the center line L is about 45 ° or less ( low gradient ), It has been found that the pressure loss is higher than that of the vertical herringbone type and that a high heat transfer coefficient cannot be obtained.

  Specifically, the depth of the recess 132 corresponds to the interval between the stacked heat transfer plates 100, but the pitch between the protrusion 131 and the recess 132 when the interval between the heat transfer plates 100 is 4 mm is as follows. When the distance between the heat transfer plates 100 is 2 mm, the pitch of the ridges 131 and the ridges 132 is approximately twice. Then, when the heat transfer plates 100 are stacked, the distance at which the ridges 131 of the adjacent heat transfer plates 100 contact each other is such that the deep ridges 132 are longer than the shallow ridges 132 and the unit area is larger. The number of contact points per hit is reduced. Therefore, in the heat transfer plate 100 in which the deep ridges 132 are formed, the fluid does not flow along the ridges 132 but overcomes the ridges 131, and high heat transfer performance is not exhibited.

  On the contrary, the heat transfer plate 100 in which the concave streaks 132 shallower than about 3.5 mm are formed with the protrusions 131 of the adjacent heat transfer plates 100 in comparison with the heat transfer plates 100 in which the deep concave streaks 132 are formed. Since the contact distance is shortened and the number of contact points is increased, the fluid becomes difficult to get over the ridge 131, and the ratio of flowing along the ridge 132 is increased, so that the fluid is dispersed on the heat transfer section, and as a result, high Heat transfer performance is demonstrated.

  In addition, since the heat transfer plate 100 is used in a vertical posture, the angle β of the ridge 131 and the ridge 132 with respect to the short sides A and B is small, for example, 30 ° (the ridge with respect to a line parallel to the center line L). When the angle 131 of the groove 131 and the groove 132 is large, for example, 60 °), the ridge 131 and the groove 132 have a low slope, so that the fluid flows along the groove 132 without getting over the protrusion 131. Cheap.

  Conversely, the angle β of the ridge 131 and the recess 132 with respect to the short sides A and B is large, for example, 60 ° (the angle α of the ridge 131 and the recess 132 with respect to a line parallel to the center line L is, for example, 30 °. And the protrusion 131 and the recess 132 have steep slopes, so there is no significant difference between the resistance of the fluid flow along the recess 132 and the resistance of the fluid flow over the protrusion 131. , The fluid may exceed the ridge 131 and may not flow along the ridge 132.

Therefore, if the angle α with respect to the line parallel to the center line L is larger than about 45 ° ( steep ), the fluid does not get over the ridge 131 and does not get over the ridge 131. By flowing along the stripes 132, the heat transfer section is uniformly dispersed and high heat transfer performance is exhibited.

  In short, in the horizontal herringbone, the concave stripe 132 is shallow (for example, the forming depth of the convex stripe and the concave stripe is about 3.5 mm or less), and the inclination of the convex stripe 131 and the concave stripe 132 is a low gradient (for example, When the angle α with respect to a line parallel to the center line L is greater than about 45 °), the fluid flows uniformly through the heat transfer section 110.

  However, when the ridges 131 and the ridges 132 have a low gradient, the angle γ of the folded portion 133 at both ends of the ridges 131 and the ridges 132 becomes tight (pointed). The fluid flowing along the recess 132 is unlikely to return smoothly at the folded portion 133, and the pressure loss increases. This problem cannot be solved by the heat transfer plate 100 provided with the hard beads 111a and the soft beads 111b having different angles with respect to the center line L as in the plate heat exchanger described in Patent Document 1.

  Accordingly, the present invention provides a horizontal herringbone in which a corrugated heat transfer section in which a plurality of inclined ridges and recesses are alternately formed is provided so that the inclination directions of the ridges and recesses are alternately reversed. Plate type heat exchange with a heat transfer plate that has high heat transfer performance and prevents the pressure loss of the fluid from becoming large at the folded part where the direction of inclination of the ridges and recesses changes. It is an object to provide a vessel.

In the plate heat exchanger according to the present invention, the corrugated heat transfer section in which a plurality of inclined ridges and recesses are alternately formed has one end portion in which the directions of inclination of the ridges and recesses are alternately reversed. A plurality of herringbone-shaped heat transfer plates provided in the direction from the other end to the other end are stacked, and a flow path in the direction of the center line connecting the midpoints of the one end and the other end is provided between the heat transfer plates. A plate-type heat exchanger for exchanging heat between fluids via a heat transfer plate by causing different fluids to flow in each flow path, wherein the ridges and ridges of the corrugated heat transfer section are each provided with a fluid. The boundary between the adjacent corrugated heat transfer parts and the corrugated heat transfer parts provided to be inclined at an angle of 45 ° or more with respect to a line parallel to the center line of the heat transfer plate so as to flow along the concave stripe The folded part is provided with a plurality of ridges and recesses in the part, and the flow of fluid along the recesses is changed stepwise In so that, a convex strip and concave of the turned-back portion is provided to be inclined in two directions at an angle smaller than the convex strip and concave of the waveform heat transfer portion with respect to the center line and a line parallel It is characterized by.

  According to this plate heat exchanger, the ridges and the ridges are provided with a steep slope (low slope with respect to the short side of the rectangular heat transfer plate) with respect to a line parallel to the center line of the heat transfer plate. Thus, the fluid flows along the concave stripes without overcoming the convex stripes, and the convex stripes and concave stripes formed in the folded portion have a low gradient (rectangular heat transfer plate) in two directions with respect to the center line. The fluid flows along the concave stripes of the corrugated heat transfer part inclined in one direction, and the direction of the flow is changed stepwise in the folded part. Since it flows along the concave line of the corrugated heat transfer part inclined in the other direction, the pressure loss in the folded part can be reduced.

  Moreover, the plate type heat exchanger which concerns on the said invention WHEREIN: It is preferable that the protruding item | line and the concave item | line of the said folding | returning part are formed in the bent line shape bent in multiple places. According to this plate-type heat exchanger, the ridges and recesses of the folded portion are formed in a bent line shape that is bent at a plurality of locations, so that the fluid flows while gradually changing the direction in the bent line-shaped recess. Can be.

Further, in the above plate type heat exchanger according to the present invention, the length of the convex strip and concave pitch between the folded portion that is perpendicular to the longitudinal direction of the convex strip and concave of the waveform heat transfer unit It is preferable that the pitches orthogonal to each other are formed at equal intervals. According to this plate-type heat exchanger, when the pitch of the ridges and recesses of the corrugated heat transfer section and the folded section is narrow, the fluid does not flow smoothly along the recesses. In addition, by forming the recesses and the ridges and recesses of the folded portion at equal intervals, the fluid can flow smoothly along the recesses of the folded portion.

  Further, in the plate heat exchanger according to the present invention, it is preferable that the convex depth and the concave stripe forming depth of the corrugated heat transfer portion and the folded portion are formed shallowly to 3.5 mm or less. According to this plate type heat exchanger, when the formation depth of the corrugated heat transfer section and the ridges and recesses of the folded section is shallowly formed to 3.5 mm or less, when a plurality of heat transfer plates are stacked In addition, the distance at which the ridges of adjacent heat transfer plates come into contact with each other is shortened and the number of contact points is increased, so that the fluid becomes difficult to get over the ridges and can flow along the ridges.

  According to the present invention, the ridges and ridges of the corrugated heat transfer section provided steeply with respect to the center line of the heat transfer plate make the grooves not to exceed the ridges of the corrugated heat transfer section. A plurality of ridges and ridges provided at the folded portion of the boundary between the corrugated heat transfer section and the corrugated heat transfer section that are adjacent to each other, and thereby the fluid is inclined to one side of the corrugated heat transfer section. After flowing along, the plate type heat exchanger has a high heat transfer and does not increase the pressure loss at the folded part because it smoothly changes direction along the corrugation of the corrugated heat transfer part inclined to the other side. Can be provided.

It is a front view which shows one Embodiment of the heat exchanger plate which comprises the plate type heat exchanger which concerns on this invention. It is a principal part enlarged front view which shows the modification of the heat exchanger plate which comprises the plate type heat exchanger which concerns on this invention. It is a principal part enlarged front view which shows the reference example of the heat exchanger plate which comprises the plate type heat exchanger which concerns on this invention. It is a general | schematic disassembled perspective view which shows the principal part of the conventional plate type heat exchanger. It is a front view which shows the heat exchanger plate which comprises the conventional plate type heat exchanger different from FIG.

  An embodiment of a plate heat exchanger according to the present invention will be described with reference to FIGS. 1 to 3. In the following description, it is expressed as up, down, left and right as appropriate, but this is the case in the drawing, and it goes without saying that each position may be different from the drawing in actual use.

  In the plate heat exchanger according to the embodiment, the corrugated heat transfer section 11 and the folded section 12 are alternately provided in the length direction on the laminated rectangular heat transfer plate 10. A flow path is provided between the adjacent heat transfer plates 10, and the fluid flows in the flow path from the upstream side to the downstream side. In the four corners of the heat transfer plate 10, passage holes 1 to 4 serving as fluid inlets and outlets are provided. 10a communicates.

  That is, in a certain heat transfer plate 10, for example, in the drawing, the upper right passage hole 1 is a fluid inlet and the lower right passage hole 2 is an outlet, so that the upper short side A side of the heat transfer plate 10 is upstream. The lower short side B is the downstream side, the lower left passage hole 3 is the fluid inlet, and the upper left passage hole 4 is the outlet, so the lower short side B side of the heat transfer plate 10 is the upstream side. The upper short side A is the downstream side.

  And the heat-transfer plate 10 is a horizontal herringbone type, and is equipped with the waveform heat-transfer part 11 which formed alternately the several inclined ridge 11a and the recessed ridge 11b. A plurality of the corrugated heat transfer portions 11 are provided from the vicinity of the upper short side A to the vicinity of the lower short side B of the heat transfer plate 10. The ridges 11a and the ridges 11b of a certain corrugated heat transfer section 11 are inclined in one direction (in the drawing, from the upper right to the lower left direction, hereinafter referred to as “downward to the left”), and are adjacent to the corrugated heat transfer section 11. The ridges 11a and the ridges 11b of the corrugated heat transfer section 11 are inclined in the other direction (from the upper left to the lower right in the drawing, hereinafter referred to as “lower right”). It should be noted that the ridges 11a and ridges 11b on the front side of a certain heat transfer plate 10 become the ridges 11b and ridges 11a on the back side, and the fluid flows along the ridges 11b.

  The ridges 11a and the ridges 11b in any direction are inclined so that the fluid flows along the ridges 11b without getting over the ridges 11a. In other words, the ridge 11a and the ridge 11b are steep in an angle α with respect to a line K parallel to the center line L connecting the midpoints of the short sides A and B of the heat transfer plate 10 (eg, 60 ° of 45 ° or more). Is provided. In other words, the ridges 11a and the ridges 11b in any direction are provided with an angle β with respect to the short sides A and B of the heat transfer plate 10 at a low gradient (eg, 30 ° of 45 ° or less). Hereinafter, the slopes of the ridges and the ridges will be described as “low slope” in accordance with the drawings.

  In addition, the forming depth of the protrusions 11a and the recesses 11b is shallowly formed to be 3.5 mm or less, so that when the plurality of heat transfer plates 10 are stacked, the protrusions of the adjacent heat transfer plates 10 are formed. Since the distance at which the strips 11a come into contact with each other is shortened and the number of contact points increases, it becomes difficult for the fluid to get over the ridges and to flow along the ridges 11b. Note that 3.5 mm is not an exact numerical value but an approximate numerical value.

  Then, a folded portion 12 is interposed between the corrugated heat transfer section 11 formed with the left downward-facing ridge 11a and the concave stripe 11b and the corrugated heat transfer section 11 formed with the right downward ridge 11a and the concave stripe 11b. ing. The folded portion 12 is also a corrugated plate having a plurality of ridges 12a and recessed ridges 12b alternately formed. However, the folded portion 12 is formed so as to gradually change the flow of the fluid along the recessed ridges 12b. The ridges 12 a and the ridges 12 b are provided with a low gradient in two directions with respect to the angle γ with respect to the line parallel to the center line L, in other words, steep gradients with respect to the short sides A and B of the heat transfer plate 10. ing. Hereinafter, the slopes of the ridges and ridges of the folded portion 12 will be described as “steep slopes” in accordance with the drawings.

Specifically, the ridges 12a and the ridges 12b of the folded portion 12 have a "<" shape as shown in FIG. 1 and a plurality of locations as shown in FIG. are formed may also be.) fold line shape, etc. bent in at least.

  In any case, the pitch of the ridges 12a and the recesses 12b of the folded portion 12 is the same as the pitch of the ridges 11a and 11b of the corrugated heat transfer portion 11, and the ridges 12a and the recesses of the folded portion 12 are the same. Although 12b and the convex ridge 11a and the concave ridge 11b of the waveform heat-transfer part 11 are not many, one part may continue. If the pitch of the ridges 11a, 12a and the ridges 11b, 12b is narrow, the fluid does not flow smoothly along the ridges 11b, 12b, but the pitch of the ridges 12a and 12b of the folded portion 12 is transmitted in a waveform. By being formed at equal intervals with the pitch of the ridges 11 a and the ridges 11 b of the heat part 11, the fluid flows smoothly in the folded part 12.

  Here, the flow of fluid in a plate heat exchanger in which a plurality of such heat transfer plates 10 are stacked and a flow path is formed between the heat transfer plates 10 will be described.

  In FIG. 1, the fluid that has flowed into the flow path from the upper right passage hole 1 has a low gradient (for example, with respect to a line K parallel to the center line L) along the concave line 11 b facing downward to the left of the corrugated heat transfer section 11. It flows in the lower left direction at an angle α of 60 °), but reaches the folded portion 12 without getting over the ridge 11a. The direction of the flow of the fluid is changed at the turn-back portion 12, and a low gradient (for example, with respect to a line parallel to the center line L) along the downwardly extending groove 11 b of the corrugated heat transfer portion 11 on the lower side of the same flow path. And flows in the lower right direction at an angle α of 60 ° opposite to the above.

  As shown in FIG. 1, when the convex strips 12 a and the concave strips 12 b of the folded portion 12 are formed in a “<” shape, the fluid has an angle of 30 ° with respect to the center line L in the folded portion 12. After flowing in the lower left direction at γ, it flows in the lower right direction at an angle γ of 30 ° opposite to the center line L at the bent portion 12a. Therefore, the fluid does not change direction at an acute angle from the flow along the concave line 12b facing downward to the right, but flows through the folded portion 12 in two stages.

  Moreover, when the folding | turning part 12 is formed in a broken line shape as shown in FIG. 2, the fluid will change the direction in the folding | turning part 12 gradually, and will flow. Moreover, when the folding | turning part 12 is formed in circular arc shape, as shown in FIG. 3, the fluid will change the direction smoothly so that the inside of the folding | turning part 12 may curve.

  In any case, the fluid along the left downward facing groove 11b of the corrugated heat transfer section 11 is redirected without a large pressure loss by the turning section 12, and along the right lower facing groove 11b of the corrugated heat transfer section 11. Flowing. Similarly, on the downstream side, the fluid along the right downward groove 11b of the corrugated heat transfer section 11 is redirected without a large pressure loss by the turned-up section 12, and is turned to the left lower recess 11b of the corrugated heat transfer section 11. Flowing along.

  Further, in this plate heat exchanger, the convex strips 11a and the concave strips 11b of the corrugated heat transfer section 11 have a low gradient, and the molding depth of the convex strips 11a and 12a and the concave strips 11b and 12b is reduced. By increasing the depth, the number of contact points is increased, and the fluid flows along the recesses 11b and 12b, so that high heat transfer performance is exhibited. The fluid is exchanged not only in the corrugated heat transfer section 11 but also in the folding section 12.

  The present invention can be variously modified without being limited to the above embodiment. For example, as described above, the dimension and the angle α are not exact values but approximate values.

  Moreover, the folding | returning part 12 will be limited if it is the shape which changes the flow of a fluid in steps, such as what combined the circular arc-shaped part and the linear part extended from this circular arc-shaped both ends. Not a thing. Furthermore, due to the viscosity of the fluid, etc., when the pitch of the ridges 12a and the recesses 12b of the folded part 12 flows smoothly even if the pitch is narrow, the pitch of the ridges 12a and the groove 12b of the folded part 12 is narrowed, The ridges 12 a and the recesses 12 b of the folded portion 12 may be continuous with the ridges 11 a and the recesses 11 b of the corrugated heat transfer unit 11.

10 ... Heat transfer plate 11 ... Corrugated heat transfer part 11a ... Convex strip 11b ... Concave strip 12 ... Folded portion 12a ... Convex strip 12b ... Concave strip L ... Center line α ......... (parallel to the center line) Angle β (with respect to the line) .... angle (with respect to the short side)

Claims (4)

A plurality of corrugated heat transfer portions formed alternately with a plurality of inclined ridges and recesses are provided from one end to the other end with the directions of inclination of the ridges and recesses alternately reversed. Laminate multiple herringbone-shaped heat transfer plates, and provide a flow path in the direction of the center line connecting the midpoints of one end and the other end between each heat transfer plate, allowing different fluids to flow through each flow path A plate type heat exchanger that exchanges heat between fluids via a heat transfer plate,
The ridges and ridges of the corrugated heat transfer part are provided inclined at an angle of 45 ° or more with respect to a line parallel to the center line of the heat transfer plate so that the fluid flows along each ridge. A folded portion is provided by a plurality of ridges and recesses at the boundary between adjacent corrugated heat transfer portions and corrugated heat transfer portions, and the flow of fluid along the recesses is changed stepwise. The ridges and recesses of the folded portion are provided to be inclined in two directions at a smaller angle than the ridges and recesses of the corrugated heat transfer portion with respect to a line parallel to the center line. Plate heat exchanger.   The plate-type heat exchanger according to claim 1, wherein the ridges and recesses of the folded portion are formed in a bent line shape bent at a plurality of locations. And orthogonal pitch are formed at equal intervals with respect to the length direction of the convex strip and concave pitch between the folded portion that is perpendicular to the longitudinal direction of the convex strip and concave of the waveform heat transfer unit The plate-type heat exchanger according to claim 1 or 2 , wherein The plate-type heat according to any one of claims 1 to 3 , wherein a forming depth of the corrugated heat transfer portion and the ridges and recesses of the folded portion is formed shallowly to 3.5 mm or less. Exchanger.

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