JP2000292079A - Plate heat exchanger - Google Patents

Abstract

(57) [Problem] To prevent drift of a heat exchange fluid in a plate heat exchanger. SOLUTION: A plurality of heat transfer plates are stacked so that first heat exchange channels and second heat exchange channels extending in the vertical direction are alternately formed in the stacking direction of the heat transfer plates. At the lower and upper ends of the heat transfer plate (P1), water inflow openings (75
a) and a water outlet (76a). Refrigerant inflow opening (73
a) is formed at the center in the width direction of the heat transfer plate (P1) and above the water inflow opening (75a).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate heat exchanger, and more particularly, to a countermeasure for preventing a heat exchange fluid from drifting.

[0002]

2. Description of the Related Art Conventionally, various heat exchangers have been used in air conditioners, refrigeration units, refrigeration units, and the like. Among those heat exchangers, the plate heat exchanger is
It is known as a compact heat exchanger having a large heat transmission coefficient.

As shown in FIG. 9, a plate heat exchanger is constituted by stacking a plurality of heat transfer plates (P, P,...) Between two frames (f1) and (f2). ing.

[0004] Each heat transfer plate (P) is made of a metal flat plate, and when laminated, the peripheral edges of the heat transfer plates come into contact with each other so that the heat exchange passages (A, B) of the fluid are interposed between the heat transfer plates. , A, B,...) Are formed, and the abutting portions are joined by brazing to be integrally formed.

Openings (a, b, c, d) are provided at the four corners of the heat transfer plate (P), and seal portions (e) are provided around the openings (a, b, c, d). The inflow space (A1) and the outflow space (A2) that communicate only with one heat exchange flow path (A)
And the inflow space (B1) communicating only with the other heat exchange flow path (B).
And an outflow space (B2). In FIG. 9, one of the fluids flows from the inlet pipe into the inflow space (A1) as shown by the solid arrow, and is distributed from the inflow space (A1) to each heat exchange flow path (A). The fluid that has flowed through the heat exchange flow path (A) is recovered in the outflow space (A2) and then flows out through the outlet pipe. The other fluid flows through the heat exchange flow path (B) from the inlet pipe through the inflow space (B1), passes through the outflow space (B2), and flows out through the outlet pipe, as indicated by the dashed arrow. In this way, the fluids flowing through the two heat exchange channels (A) and (B) exchange heat with each other.

[0006]

By the way, as shown in FIG. 10, in the conventional plate type heat exchanger, the inflow openings (a) and (c) and the outflow openings (b) and (b) of the fluid performing the heat exchange. Since d) was provided at the four corners of the heat transfer plate (P), it was easy to cause fluid drift.

In one of the heat exchange channels for the fluid,
In the vicinity of the inflow opening and the outflow opening of the other fluid, a dead water area where the one fluid does not flow much occurs. This also causes a drift. Then, due to the above-described drift of the fluid, the following problem occurs.

[0008] That is, when the drifting of the cooling fluid occurs, a region where the flow velocity of the cooling fluid is high and a region where the flow velocity of the cooling fluid is low occur in the heat exchange flow path. In such a case, the cooling fluid having a high flow velocity is more likely to perform heat exchange than the cooling fluid having a low flow velocity. The temperature is lower than that of the fluid to be cooled which is cooled by the fluid.

For example, as shown in FIG. 10, when a refrigerant is used as a cooling fluid and water is used as a fluid to be cooled,
When a drift occurs such that the flow velocity is high on the left side of the heat transfer plate above the refrigerant inflow opening (a) and the flow velocity is low on the right side, the water temperature in the right side area is lower than that in the left side area. In addition, the water temperature distribution becomes non-uniform in the width direction of the flow path (the horizontal direction in FIG. 10).

When the water is to be cooled to a supercooled state, when the supercooled water falls below a certain limit temperature, the supercooled state is eliminated, and the subcooled state is eliminated, and the iced portion is removed. It becomes seed ice and becomes a factor to eliminate the supercooled state of other supercooled water. Therefore, in order to maintain the supercooled state of the supercooled water, it is necessary to maintain all the regions at a temperature higher than the limit temperature.

On the other hand, in order to stably cool the water to the supercooled state, it is preferable to make the temperature of the supercooled water in the heat exchanger uniform. For example, when supercooled water having an average temperature of −3 ° C. is generated, all regions have a temperature of −3 ° C., compared to a state in which the temperature distribution is locally nonuniform and the temperature distribution is uneven. A uniform state is preferred. Assuming that the limit temperature for eliminating supercooling is −4 ° C., in such a non-uniform state, icing occurs in a region of −4 ° C. or less.

However, as described above, in the conventional plate-type heat exchanger, the temperature of the supercooled water is not uniform as shown in FIG. 10 due to the drift of the refrigerant flowing through each heat exchange channel. Therefore, in order to prevent blockage of the flow path due to elimination of the supercooled state, it is necessary to set the temperature of the lowest temperature region of the supercooled water higher than the limit temperature. As a result, the average temperature of the supercooled water cannot be lowered, and there is a limit to improving the efficiency of generating the supercooled water.

[0013] In addition to the case where the supercooled water is generated (not limited to the case where the fluid to be cooled is water), the cooling fluid and the fluid to be cooled are generally used in order to enhance the heat exchange efficiency of the plate heat exchanger. It is desired to prevent the cooling fluid from drifting.

SUMMARY OF THE INVENTION The present invention has been made in view of the foregoing, and an object of the present invention is to provide a high-performance plate-type heat exchanger in which the flow of fluid in the heat exchanger is small.

[0015]

According to the present invention, at least one of the heat exchange fluid inflow openings is formed at the center of the heat transfer plate in the width direction.

Specifically, the plate heat exchanger according to the present invention is a plate heat exchanger in which a plurality of heat transfer plates (P1, P2) are stacked, and the heat transfer plates (P1, P2 ) At least one fluid inflow opening (73a, 73b),
It is formed at the center in the width direction of the plate.

The plurality of heat transfer plates (P1, P2) have first and second heat exchange channels (61, 62) extending vertically in both sides of each heat transfer plate (P1, P2). The first fluid inflow openings (73a, 73b) that are stacked so as to form and flow through the first heat exchange channel (61) are formed below the heat transfer plates (P1, P2), and The inflow openings (75a, 75b) of the second fluid flowing through the exchange flow path (62) may be formed below the inflow openings (73a, 73b) of the first fluid.

Further, another plate-type heat exchanger according to the present invention has a first fluid inflow opening (73a, 73b) and a first fluid outflow opening (74a, 74b).
b) are formed vertically separated from each other, and the second fluid inflow openings (75a, 75b) and the outflow opening for heat exchange with the first fluid are formed.
(76a, 76b) is a plate heat exchanger formed by stacking a plurality of heat transfer plates (P1, P2) formed vertically separated from each other, between the heat transfer plates (P1, P2) The first heat exchange flow path (61) through which the first fluid flows and the second heat exchange flow path (62) through which the second fluid flows are provided by the heat transfer plates (P1, P
The heat transfer plates (P1, P2) are formed alternately in the stacking direction of (2), and the first fluid inflow openings (73a, 73b) of the plurality of heat transfer plates (P1, P2) are located at the center in the width direction of the heat transfer plates (P1, P2). While being formed in the section, the first fluid from the first fluid introduction pipe (53) is
(61), a first fluid inflow space (63) is formed, and the first fluid outflow openings (74a, 74) of the plurality of heat transfer plates (P1, P2) are formed.
b) forms a first fluid outflow space (64) for recovering a first fluid from the first heat exchange flow path (61) and leading it to a first fluid outlet pipe (54); The second fluid inflow openings (75a, 75b) of (P1, P2) are formed below the first fluid inflow openings (73a, 73b), while the second fluid inflow openings (75, 75b) extend from the second fluid introduction pipe (55). A second fluid inflow space (65) for distributing the second fluid to the second heat exchange flow path (62) is formed, and the plurality of heat transfer plates (P1, P
The second fluid outflow opening (76a, 76b) of the second fluid is provided in the second fluid outflow space (76) for recovering the second fluid from the second heat exchange flow path (62) and guiding it to the second fluid outlet pipe (56). 66).

As described above, the first fluid inflow opening (73a, 7a)
3b) is formed at the center in the width direction of the heat transfer plates (P1, P2), so that the first fluid flowing into the first heat exchange channel (61) flows from the inflow openings (73a, 73b). Heat transfer plate (P1, P2)
Flows evenly over the entire width direction. As a result, the first fluid is less likely to drift, and the heat exchange efficiency is improved.

First and second heat exchange channels extending in the vertical direction
(61, 62) are formed, and the first fluid inflow opening (73a,
73b) is formed below the heat transfer plates (P1, P2), and the second fluid inflow openings (75a, 75b) are connected to the first fluid inflow openings (73a, 73b).
The first fluid flows through the heat exchange flow path (61) without being affected by the inflow openings (75a, 75b) of the second fluid. Therefore, since the dead zone of the first fluid is not formed due to the presence of the inflow openings (75a, 75b) of the second fluid, the drift of the first fluid is suppressed. Even if the first fluid and the second fluid are two-phase fluids, these fluids flow from the lower side to the upper side of the heat transfer plates (P1, P2). Does not occur.

Note that the first fluid may be a fluid whose temperature changes with heat exchange.

When a drift occurs in the fluid whose temperature changes with heat exchange, the temperature distribution of the cooling fluid along the width direction of the heat transfer plate in the heat exchanger becomes non-uniform, and the heat exchange efficiency decreases. According to the above, such a drift is prevented, and the unevenness of the temperature distribution of the fluid whose temperature changes with the heat exchange is corrected, so that the heat exchange efficiency is particularly improved.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

<Embodiment 1> As shown in FIG. 1, a plate heat exchanger (50) of Embodiment 1 exchanges heat between a refrigerant (R407C) as a first fluid and water as a second fluid. , To cool the water to a supercooled state. This plate type heat exchanger (50) is configured by alternately stacking two types of heat transfer plates, a first plate (P1) and a second plate (P2), and joining them integrally by brazing. ing.

In FIG. 1, the plate located on the most front side includes a refrigerant inlet pipe (53), a refrigerant outlet pipe (54), and a water inlet pipe (5).
5) and the water outlet pipe (56) are joined. Water inlet pipe (55)
The water outlet pipe (56) is provided at the center of the heat transfer plate in the width direction (the horizontal direction shown in FIG. 1), the water inlet pipe (55) is located at the lower end of the plate, and the water outlet pipe (56) is located at the plate. Are respectively joined to the upper ends of the. The refrigerant inlet pipe (53) is joined above the water inlet pipe (55) and at the center in the width direction of the heat transfer plate, and the refrigerant outlet pipe (54) is below the water outlet pipe (56) for heat transfer. It is joined to the end in the width direction of the plate (the right end in FIG. 1). The refrigerant inlet pipe (53), the refrigerant outlet pipe (54), the water inlet pipe (55), the water outlet pipe (56) are a refrigerant inflow space (63), a refrigerant outflow space (64), and a water inflow space (described later), respectively. 65), and communicates with the water outflow space (66).

As shown in FIGS. 2 and 3, the first plate
Both (P1) and the second plate (P2) have a refrigerant inlet pipe (53),
The first opening (73) which is a refrigerant inflow opening is provided at a position corresponding to the refrigerant outlet pipe (54), the water inlet pipe (55), and the water outlet pipe (56).
a), (73b), second openings (74a), (74b), which are refrigerant outflow openings
Third openings (75a) and (75b) are formed as water inflow openings, and fourth openings (76a) and (76b) are formed as water outflow openings.
And a plurality of first plates (P1) and second plates (P2)
Are alternately stacked, so that the first openings (73a), (73b)
Refrigerant inflow space consisting of a substantially cylindrical space partitioned by
(63), a refrigerant outlet space (64) consisting of a substantially cylindrical space defined by the second openings (74a) and (74b), and third openings (75a) and (75).
A water inflow space (65) composed of a substantially rectangular parallelepiped space defined by b) and a water outflow space (66) composed of a substantially rectangular parallelepiped space defined by the fourth openings (76a) and (76b) are formed respectively. Have been.

Next, the configuration of the heat transfer plates (P1) and (P2) will be described. Both plates (P1) and (P2) are made of a flat plate made of metal (for example, stainless steel), and have a wave-shaped heat transfer surface (81a), (82a), which will be described later, and a convex portion that maintains a space between the plates.
(68a), (69a), (77a), etc. are formed by press working. The edges of both plates (P1) and (P2) are
1) and (P2) are entirely bent slightly so that the peripheral portions thereof overlap each other to form the side surface of the heat exchanger when they are stacked. In other words, the bent peripheral portions form side surfaces of the heat exchanger by overlapping.

FIG. 2 shows the front side of the first plate (P1), and FIG. 3 shows the front side of the second plate (P2). Both plates (P
The peripheral portions of 1) and (P2) are bent from the front side to the back side. 1st plate (P1) and 2nd plate (P2)
Are stacked such that one front side faces the other back side. Between the front side of the first plate (P1) and the back side of the second plate (P2), a refrigerant flow passage (61) through which the refrigerant flows is formed. On the other hand, the back side of the first plate (P1) and the second plate (P2)
A water flow passage (62) through which water flows is formed between the front side and the front side.

The first plate (P1) and the second plate (P2) have substantially rectangular fourth openings (76a) and (76b) at the upper end, and substantially rectangular third openings (75a) and (75a) at the lower end. (75b) is formed. Further, circular second openings (74a) and (74b) are formed below the fourth openings (76a) and (76b) at the right end of the plate, and are formed above the third openings (75a) and (75b). In the center of the plate in the width direction, circular first openings (73a) and (73b) are formed. The first openings (73a) and (73b) and the second openings (74a) and (74b)
Each is formed to have the same diameter as the refrigerant inlet pipe (53) and the refrigerant outlet pipe (54).

The fourth openings (76a), (76b) and the third openings (75a),
(75b) is formed in a substantially rectangular shape elongated in the width direction of the heat transfer plates (P1) and (P2), that is, in the width direction of the water flow passage (62). Fourth openings (76a) and (76b) and third openings (75a) and (75b)
Is an opening having a larger opening area than the first openings (73a) and (73b), and is provided at the center in the width direction of the heat transfer plates (P1) and (P2). Further, the fourth openings (76a) and (76b) and the third openings (75a) and (75b) have a horizontal length of the heat transfer plate.
(P1), (P2) is formed slightly shorter than the width, and the vertical length (opening length of the water flow passage (62) in the flow direction) is the water outlet pipe (56) and the water inlet pipe ( The length is almost equal to the diameter of 55). That is, the fourth openings (76a), (76b) and the third
The openings (75a) and (75b) should be as large as possible according to the width of the heat transfer plates (P1) and (P2) and the diameter of the water outlet pipe (56) and the water inlet pipe (55). Is formed.

Around the first openings (73a) and (73b) of the first plate (P1) and the second plate (P2), a refrigerant inflow portion (57a) for preventing the refrigerant from flowing in the refrigerant flow passage (61) is prevented. ) And (57b) are formed. As shown in FIG. 4, the refrigerant inflow portion (57a) of the first plate (P1) has a sealing portion (58a) formed in a convex shape from the back side to the front side (front side in FIG. 4), and a flat portion. (Five
9a). On the other hand, the second plate (P2)
The refrigerant inflow portion (57b) includes a seal portion (58b) formed in a convex shape from the front side to the back side, and a flat portion (59b).

The flat portions (59a) and (59b) have first openings (73a) and (73).
(b) is formed in a substantially annular shape concentric with the first openings (73a) and (73b) so as to cover the periphery thereof, and has flat portions (93) and (93) continuous with the first opening (73a). ing. Then, the front side of the seal portion (58a) of the first plate (P1) comes into contact with the back side of the seal portion (58b) of the second plate (P2) and is brazed, so that the flat portions (93), ( 93) (60), (6
0) is formed. As shown in FIG. 5, in this embodiment, since the seal portions (58a) and (58b) adjacent to the flat portion (93) are formed in an arc shape, the refrigerant inflow port (60) has a circular cross section. It becomes a communication port.

As shown in FIG. 4, the refrigerant inlets (60), (60)
The first opening (73) so that the refrigerant flows diagonally downward left and right from the refrigerant inflow space (63) toward the refrigerant flow passage (61).
a) It is provided in a C-shape that opens downward from the center of. Specifically, a horizontal line passing through the centers of the first openings (73a) and (73b)
(N) and the center axis (M) of the refrigerant inlet (60) are 22.5
It is formed so as to form an angle of degrees. Each of the refrigerant inlets (60) is formed in an opening smaller than the first openings (73a) and (73b). Specifically, the opening area of each refrigerant inlet (60) is determined by the distance between the heat transfer plates (P1) and (P2) and the first opening (73a).
(73b) is smaller than the area multiplied by the perimeter.

On the other hand, the back side of the flat portion (59a) of the first plate (P1) comes into contact with the front side of the flat portion (59b) of the second plate (P2) and is brazed to form the first opening (73a). ), (73b)
Is separated from the water flow passage (62), and as a result, the refrigerant inflow space
(63) and a water flow passage (62) are defined.

The refrigerant inflow portions (57a) and (57b) are connected to the heat transfer surfaces (8
1a) and (81b). Conversely, heat transfer surfaces (81a) and (81b) are formed around the refrigerant inflow portions (57a) and (57b). That is, the first openings (73a) and (73b) are provided on the heat transfer surfaces (81a) and (81b).

As shown in FIGS. 2 and 3, the second opening (74
a) and (74b), flat portions (67a) and (67b) covering the periphery of the second openings (74a) and (74b), and approximately semispherical first convex portions (68a) and (6).
8b), and refrigerant outflow portions (70a) and (70b) formed of the second convex portions (69a) and (69b) in a semicircular shape. 1st plate
The first protrusion (68a) and the second protrusion (69a) of (P1) are convex from the back side to the front side, while the second plate (P2)
The first convex portion (68b) and the second convex portion (69b) are convex from the front side to the rear side. When the first plate (P1) and the second plate (P2) are stacked, the first plate (P1)
The front side of the projection (68a) and the first projection (68b) of the second plate (P2)
The back side of the first plate (P1) is brought into contact with the front side of the second protrusion (69a) of the first plate (P1) and the second protrusion (69b) of the second plate (P2). A predetermined distance is maintained between the front side of the plate (P1) and the back side of the second plate (P2), and a flow path from the refrigerant flow passage (61) to the refrigerant outflow space (64) is secured. On the other hand, the flat portion (59a) of the first plate (P1)
Of the second plate (P2) and the front side of the flat portion (59b) of the second plate (P2) are abutted and brazed so that the second openings (74a), (7
4b) is partitioned from the water flow passage (62), and the refrigerant outflow space (64) and the water flow passage (62) are partitioned.

A flat portion is provided around the third openings (75a) and (75b).
Water inflow portions (71a) and (71b) formed of (72a) and (72b) and a plurality of convex portions (77a) and (77b) are formed. Convex (77a), (77b)
Are provided in a scattered manner so as to surround the third openings (75a) and (75b), and the flat portions (72a) and (72b) have the third openings (75a) and (75b) and the convex portion (77a). , (77b). The convex portion (77a) of the first plate (P1) is convex from the front side to the rear side, while the convex portion (77a) of the second plate (P2) is convex.
(77b) is convex from the back side to the front side. Therefore, when the first plate (P1) and the second plate (P2) are stacked, the front side of the flat portion (72a) of the first plate (P1) and the flat portion (72b) of the second plate (P2) are stacked. The third openings (75a) and (75b) are separated from the refrigerant flow passage (61) by being in contact with the back side and brazing, and the refrigerant flow passage (61) and the water inflow space are separated.
(65). On the other hand, the projections (7
7a) and the front side of the projection (77b) of the second plate (P2) are brought into contact with each other and brazed, so that the first plate (P2)
A predetermined distance is maintained between the back side of 1) and the front side of the second plate (P2), and a flow path from the water inflow space (65) to the water flow passage (62) is secured. That is, water flows into the water flow passage (62) from all around the third openings (75a) and (75b).

Around the fourth openings (76a) and (76b), as with the third openings (75a) and (75b), flat portions (78a) and (78b) and a plurality of convex portions (79a) and (79a) Water outflow portions (80a) and (80b) composed of 79b) are formed. The water outlets (80a), (80b) are the water inlets (71a),
(71b), and separates the refrigerant flow passage (61) from the water outflow space (66) and secures a flow path from the water flow passage (62) to the water outflow space (66). ing. Therefore, the water flows out of the water flow passage (62) through the entire periphery of the fourth openings (76a) and (76b), and flows into the water flow passage (62).

Next, the first plate (P1) and the second plate
The heat transfer surfaces (81a) and (81b) of (P2) will be described. Each heat transfer surface
(81a) and (81b) are flat peaks (solid lines in FIGS. 2 and 3) and flat valleys (FIGS. 2 and 3).
(Broken line portion in FIG. 2) are alternately formed. This wavy shape is an upwardly inclined portion (86) that inclines upward as the extension direction of the peaks and valleys goes to the right.
At the same time, a downwardly inclined portion (87) inclined downward is formed in a so-called herringbone shape in which alternately formed, and the upwardly inclined portion (86) and the downwardly inclined portion (87) have a peak portion and a valley portion. Are arranged so that the arrangement direction of them is the longitudinal direction (vertical direction) of the plates (P1) and (P2). Heat transfer surface of the first plate (P1) (81
In a) and the heat transfer surface (81b) of the second plate (P2), the extending directions of the peaks and the valleys are different from each other. That is, the first
In the plate (P1), as shown in FIG. 2, a herringbone shape is formed in the order of the upper inclined portion (86) and the lower inclined portion (87) from the left end, while the second plate (P2) has As shown in FIG. 3, from the left end, a downward inclined portion (87) and an upward inclined portion (86)
The herringbone shape is formed in this order.

The heat transfer surfaces (81a) and (81b) will be described in more detail. As shown in FIG. 6, the heat transfer surfaces (81a) of the first plate (P1)
a) is a valley (83) having a predetermined depth and a first peak (8) having a predetermined height.
4) and a second peak portion (85) lower in height than the first peak portion (84). The first mountain part (84) and the second mountain part (85)
They are formed alternately with the valleys (83) interposed therebetween. That is, the wave shape of the heat transfer surface (81a) is the first peak (84) and the valley (8
3), a second peak (85), and a valley (83) are sequentially and repeatedly provided. In the present embodiment, the second peak (85)
Is half the height of the first peak (84).

The heat transfer surface (81b) of the second plate (P2) has a first valley (88) having a predetermined depth and a second valley (89) which is shallower than the first valley (88). ) And a ridge (90) having a predetermined height. The first valleys (88) and the second valleys (89) are formed alternately with the ridges (90) interposed therebetween. In other words, the heat transfer surface (8
The wave shape of 1b) has a first valley (88), a peak (90), and a second valley (8).
9), the ridges (90) are repeatedly provided in order. In the present embodiment, the depth of the second valley (89) is the first valley (89).
It is half the depth of the valley (88).

Then, the first plate (P1) and the second plate
(P2) are alternately laminated, so that the first ridge (84) of the heat transfer surface (81a) and the first valley (88) of the heat transfer surface (81b) abut, while the heat transfer The second valley (89) of the surface (81a) and the second ridge (85) of the heat transfer surface (81b) are separated from each other at a predetermined interval,
A refrigerant flow passage (61) is formed between the front side of the heat transfer surface (81a) and the back side of the heat transfer surface (81b). In addition, the valley of the heat transfer surface (81a) (8
3) and the ridge (90) of the heat transfer surface (81b) abut against the heat transfer surface (81a).
A water flow passage (62) is formed between the back side of the heat transfer surface and the front side of the heat transfer surface (81b).

The first ridge portion (84) of the heat transfer surface (81a) and the heat transfer surface (81)
The first valley (88) of b) is joined by brazing. In contrast, the valley (83) of the heat transfer surface (81a) and the heat transfer surface (81a)
The ridge (90) in b) is merely in contact and not joined. That is, when water freezes in the water flow passage (62), the heat transfer plates (P1) and (P2) are deformed so that the valley (83) and the ridge (90) are separated from each other, and Is adapted to absorb the volume expansion.

Next, the flow of refrigerant and water in the plate heat exchanger (50) will be described. As shown in FIG.
First, the refrigerant flows from the refrigerant inlet pipe (53) into the refrigerant inflow space (63), and further flows through the refrigerant inflow port (60) into the refrigerant flow passage (61). Then, it flows through the refrigerant flow passage (61), exchanges heat with water in the adjacent water flow passage (62), evaporates, and cools the water. The evaporated refrigerant flows through the refrigerant outflow space (64), flows out of the heat exchanger (50), and flows through the refrigerant outlet pipe (54). on the other hand,
Water flows into the water inflow space (65) through the water inlet pipe (55),
The water flows into the water flow passage (62) from the water inflow space (65). Then, the refrigerant flows through the water flow passage (62), exchanges heat with the refrigerant in the adjacent refrigerant flow passage (61), is cooled, and enters a supercooled state.
The water cooled to the supercooled state passes through the water outflow space (66), flows out of the heat exchanger (50), and flows through the water outlet pipe (56).

Here, the first opening (7
3a) and (73b) are provided at the center in the width direction of the heat transfer plates (P1) and (P2), so that the refrigerant flows evenly into the refrigerant flow passages (61). In addition, the refrigerant inflow portions (57a) and (57b)
a), (81b), the refrigerant inflow section (57
The refrigerant flowing out of the refrigerant inlet space (63) from (a), (57b) is stirred by the heat transfer surfaces (81a), (81b) immediately after the refrigerant flows out. Therefore, the state is dispersed immediately after the outflow. A refrigerant inlet (60) for communicating the refrigerant inflow space (63) with the refrigerant flow passage (61),
(60) is a small opening and is provided in a C-shape, so that the refrigerant in the refrigerant inflow space (63) accelerates when passing through the refrigerant inlets (60), (60), It flows out vigorously and flows into the refrigerant flow passage (61) in a more dispersed state.
Therefore, the refrigerant flowing through the refrigerant flow passage (61) has a uniform flow without drift.

In the present embodiment, the refrigerant flowing through the heat exchanger (50) is a non-azeotropic mixed refrigerant. However, the temperature of the non-azeotropic mixed refrigerant increases with evaporation, so that the refrigerant inside the heat exchanger (50) Causes a temperature distribution. However, in the present heat exchanger (50), since the refrigerant flows uniformly without any drift, the refrigerant temperature distribution in the width direction of the heat transfer plates (P1) and (P2) in the refrigerant flow passage (61) becomes uniform.

On the other hand, the water inflow space (65) is provided with a heat transfer plate (P
1) and (P2) are provided at the center in the width direction and have a large cross-sectional area.
The flow velocity of the water flowing into the water flow passage (65) decreases, and the flow of the water flowing into the water flow passage (62) becomes smooth. In other words, the water inflow space (6
5) serves as a buffer for the water flow and prevents its drift. Similarly to the water inflow space (65), the water outflow space (66) is provided at the center in the width direction of the heat transfer plates (P1) and (P2), and has a large cross-sectional area. The water flowing through the passage (62) flows almost uniformly over the entire width of the heat transfer plates (P1) and (P2). Then, the supercooled water in each water flow passage (62) is mixed at a reduced flow velocity in the water outflow space (66), and then flows into the water outlet pipe (56). Is less likely to occur.

As a result, both the refrigerant and the water flow uniformly without any drift, and the heat transfer plate (P
The water temperature distribution in the width direction of (1), (P2) becomes uniform.

Therefore, according to the present embodiment, since the first openings (73a) and (73b), which are the inflow openings of the refrigerant, are formed at the center in the width direction of the plate, the refrigerant flow from the refrigerant inflow space (63). The refrigerant flowing into the passage (61) is easily spread evenly in the width direction of the plate, and drift can be effectively prevented.

Further, since the first openings (73a) and (73b) forming the refrigerant inflow space (63) are provided inside the heat transfer surfaces (81a) and (81b), the first openings (73a) and (81b) are formed from the refrigerant inflow space (63). The refrigerant flowing into the refrigerant flow passage (61) immediately after flowing into the refrigerant flow passage (61) has a heat transfer surface (8).
It is easily dispersed because it is stirred by 1a) and (81b).
As a result, drifting of the refrigerant is suppressed.

The first openings (73a), (73
b) is formed above the third openings (75a) and (75b), which are water inflow openings, that is, downstream of the third openings (75a) and (75b).
Due to the presence of (a) and (75b), a dead water region of the refrigerant does not occur in the refrigerant flow passage (61).

Further, around the first opening (73), the refrigerant inflow portion (5)
7), and the refrigerant inflow space (63) and the refrigerant flow passage (61) are communicated by the refrigerant inflow port (60), which is a small opening, so that the refrigerant flows from the refrigerant inflow port (60) through the refrigerant inflow space. It flows into the (63) vigorously and spreads widely in the width direction of the heat transfer plates (P1) and (P2). Therefore, the drift of the refrigerant is further suppressed.

Further, the refrigerant inlets (60), (60) are provided with first openings.
There are two openings from the centers of (73a) and (73b), obliquely downward and rightward, and open diagonally downward to the left. These openings (60) and (60) are arranged in a C-shape. Therefore, when the refrigerant flows into the refrigerant flow passage (61), it flows diagonally right and left and downward. Therefore, the refrigerant is influenced by the main flow flowing upward in the refrigerant flow passage (61), and as a result, the drift of the refrigerant is more effectively mitigated, and the refrigerant flows through the refrigerant flow passage (61) in a more uniform state. .

In particular, since a non-azeotropic mixed refrigerant is used as the refrigerant, if there is a drift in the refrigerant, the temperature distribution becomes non-uniform in the width direction of the plate. Since the drift of the refrigerant is prevented, the temperature distribution of the refrigerant becomes uniform in the width direction of the plate. Therefore, the effect of preventing drift is more remarkably exhibited.

Further, a third opening (75a), which is a water inflow opening,
(75b) has a large opening, so the water inflow space (65)
Increases the volume. Therefore, the water inflow space (65) serves as a buffer for the water flow, and the water flowing from the water inlet pipe (55) decelerates in the water inflow space (65). Therefore, the water inflow space (6
Since the flow of the water from 5) to the water flow passage (62) can be made smooth, the drift of the water can be suppressed.

The fourth openings (76a) and (76b) are also connected to the third openings (75a).
Similar to (a) and (75b), the heat transfer plates (P1) and (P2) were formed wide in the width direction and made large openings, so the water inflow space (65) to the water outflow space (66) The flow of the water in the water flow passage (62) toward the flow becomes smooth. Furthermore, water outflow space (66)
The supercooled water flowing through the water flow passages (62) merges in the water outflow space (66) at a low flow rate, since the volume of the water flow path also increases. Therefore, it is possible to prevent the supercooled state from being eliminated at the time of merging, so that freezing in the heat exchanger can be prevented.

The third opening (75a), (75b) and the fourth opening
Since (76a) and (76b) are formed at the center in the width direction of the heat transfer plates (P1) and (P2), the drift of water flowing through the water flow passage (62) can be further suppressed.

The third opening (75a), (75b) and the fourth opening
(76a) and (76b) are formed in an elongated shape in the width direction of the heat transfer plates (P1) and (P2), and are formed widely over almost the entire area in the width direction. , (P2) and the water flow passage (62) from the water inflow space (65)
And flows out from the water flow passage (62) to the water outflow space (66). As a result, the drift of water can be further suppressed.

As described above, in the present embodiment, since the drift of the refrigerant and the water can be suppressed, the amount of heat exchange can be increased. Further, as shown in FIG. 7, the temperature distribution of water becomes uniform in the width direction of the plate, so that the supercooled state of water can be stabilized. In FIG. 7, illustration of the heat transfer surfaces (81a) and (81b) is omitted.

<Other Embodiments> As shown in FIG.
The third opening (75a), which is the inflow opening of water, has the same form as the first opening (73a), and the fourth opening (76a), which is the outflow opening of water, has the same form as the second opening (74a), The third opening (75a) is formed at the center in the width direction of the heat transfer plate and below the first opening (73a), and the fourth opening (76a) is substantially the same height as the second opening (74a). Alternatively, it may be formed on the side of the heat transfer plate on the opposite side (left side in FIG. 8) from the second opening (74a).

In the first embodiment, since the first openings (73a) and (73b) are provided at a predetermined distance from the water inflow portions (71a) and (71b), the refrigerant inlet (60) faces obliquely downward. However, the opening direction of the coolant inlet (60) can be changed according to the position of the first opening. For example, when the first opening is provided below the first openings (73a) and (73b) of the first embodiment, the refrigerant inlet (60) is provided horizontally from the center of the first opening. You may. Also, connect the first opening to the heat transfer surface (8
1a) and (81b), they are formed at the lowermost end.
0) may be provided slightly obliquely upward from the center of the first opening. Also in these cases, the drift of the refrigerant is prevented, and the same effect as in the first embodiment can be obtained.

The number of refrigerant inlets (60), (60) is not limited to two, but is three
There may be more than one.

The refrigerant is not limited to the non-azeotropic refrigerant mixture, but may be another refrigerant such as a pseudo-azeotropic refrigerant or a single refrigerant. Further, the cooling fluid is not limited to the refrigerant, but may be brine, water, or the like. The fluid to be cooled is not limited to water, but may be brine or a refrigerant. That is, any heat exchange fluid can be used in the present plate heat exchanger.

[0064]

As described above, according to the present invention, the inflow opening of the first fluid is formed at the center in the width direction of the heat transfer plate. And flows uniformly over the entire width direction, thereby preventing its drift. As a result, the heat exchange efficiency is improved.

The first and second heat exchange channels extending in the vertical direction are formed, the first fluid inflow opening is formed below the heat transfer plate, and the second fluid inflow opening is formed in the first fluid inflow opening. By forming the first fluid below the opening, it is possible to prevent the dead water area of the first fluid from being generated due to the inflow opening of the second fluid, and as a result, it is possible to prevent the drift of the first fluid due to the dead water area. . In addition, by flowing the first fluid or the second fluid in the up-down direction, even if these fluids are two-phase fluids, it is possible to prevent drift due to a difference in specific gravity between the two phases.

In the case where the first fluid is a fluid whose temperature changes with heat exchange, unevenness of the temperature distribution in the heat exchanger is suppressed by suppressing the drift and the heat exchange efficiency is remarkably improved. Can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a plate-type heat exchanger.

FIG. 2 is a front view of a first plate.

FIG. 3 is a front view of a second plate.

FIG. 4 is a partially enlarged view of a front surface of a first plate.

FIG. 5 is a sectional view taken along line XX of FIG. 4;

FIG. 6 is a cross-sectional view of a heat transfer surface of the plate heat exchanger.

FIG. 7 is an isotherm diagram of water in a water flow passage.

FIG. 8 is a front view of a heat transfer plate according to another embodiment.

FIG. 9 is an exploded perspective view of a conventional plate heat exchanger.

FIG. 10 is an isotherm diagram of water in a conventional plate heat exchanger.

[Explanation of symbols]

 (50) Plate heat exchanger (53) Refrigerant inlet pipe (first fluid introduction pipe) (54) Refrigerant outlet pipe (first fluid outlet pipe) (55) Water inlet pipe (second fluid introduction pipe) (56) Water outlet pipe (second fluid outlet pipe) (61) Refrigerant flow path (first heat exchange flow path) (62) Water flow path (second heat exchange flow path) (63) Refrigerant inflow space (first fluid inflow space) (64) Refrigerant outflow space (first fluid outflow space) (65) Water inflow space (second fluid inflow space) (66) Water outflow space (second fluid outflow space) (73a), (73b) First opening ( (74a), (74b) Second opening (outlet opening of first fluid) (75a), (75b) Third opening (inflow opening of second fluid) (76a), (76b) 4th opening (outflow opening of 2nd fluid) (P1), (P2) Heat transfer plate

Continued on the front page (72) Inventor Kazuhide Mizutani 1304, Kanaokacho, Sakai-shi, Osaka Daikin Industries F-term in Sakai Seisakusho Kanaoka Plant (reference) 3L103 AA05 AA09 AA18 AA37 BB33 BB42 BB44 CC02 CC28 DD08 DD09 DD55 DD57

Claims (4)

[Claims] 1. A plate type heat exchanger comprising a plurality of heat transfer plates (P1, P2) laminated, wherein at least one fluid inflow opening (73a, 73b) in the heat transfer plates (P1, P2). Is a plate-type heat exchanger formed at the center in the width direction of the plate. 2. A plurality of heat transfer plates (P1, P2), first and second heat exchange channels (61, 62) extending vertically on both sides of each heat transfer plate (P1, P2). Are formed so as to form the first fluid inflow opening (73) flowing through the first heat exchange flow path (61).
a, 73b) is formed below the heat transfer plates (P1, P2), and has an inflow opening (75) for the second fluid flowing through the second heat exchange flow path (62).
The plate heat exchanger according to claim 1, wherein the first fluid (a, 75b) is formed below the first fluid inflow opening (73a, 73b). 3. An inflow opening (73a, 73b) of the first fluid and an outflow opening (74a, 74b) are formed vertically separated from each other, and the inflow of the second fluid that exchanges heat with the first fluid. Opening (75a, 75b)
And a plurality of heat transfer plates (P1, P2) formed in such a manner that the heat transfer plates (P1, P2) are vertically separated from each other, and the heat transfer plates (P1, Between P2), a first heat exchange channel (61) through which the first fluid flows and a second heat exchange channel (61) through which the second fluid flows
Heat exchange channels (62) are alternately formed in the stacking direction of the heat transfer plates (P1, P2), and the first fluid inflow openings of the plurality of heat transfer plates (P1, P2) are formed.
(73a, 73b) are formed at the center in the width direction of the heat transfer plates (P1, P2), and pass the first fluid from the first fluid introduction pipe (53) to the first heat exchange flow path ( 61) First fluid inflow space to be distributed to
(63), and the first fluid outflow openings of the plurality of heat transfer plates (P1, P2)
(74a, 74b) is provided in the first fluid outflow space (6) for recovering the first fluid from the first heat exchange channel (61) and guiding it to the first fluid outlet pipe (54).
4), the second fluid inflow openings of the plurality of heat transfer plates (P1, P2)
(75a, 75b) is formed below the first fluid inflow opening (73a, 73b), while the second fluid introduction pipe (55)
A second fluid inflow space (65) for distributing fluid to the second heat exchange flow path (62) is formed, and a second fluid outflow opening of the plurality of heat transfer plates (P1, P2).
(76a, 76b) collects the second fluid from the second heat exchange channel (62) and guides the second fluid to the second fluid outlet pipe (56).
6) forming a plate heat exchanger. 4. The plate heat exchanger according to claim 1, wherein the first fluid is a fluid whose temperature changes with heat exchange.