JPH10141820A - Plate type heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchanger in a heat storage air conditioner the heat exchanger being capable of reducing an installation space of a water circulation circuit, and of making the whole apparatus compact. SOLUTION: The present plate type heat exchanger is adapted such that a preheating part where water involving ice nuclei is heated to melt the ice nuclei and a cooling part for supercooling water, both formed integrally. To be concrete, two kinds of heat transfer plates (P1, P2) having different corrugated patterns are alternately overlapped to form a water flow passage (W) and a refrigerant flow passage alternately. A partition part is provided on the heat transfer plates (P1, P2) for dividing the refrigerant flow passage vertically, and a high temperature refrigerant flow passage (RH) and a low temperature refrigerant flow passage (RC) are formed respectively upward and downward. These are connected with a refrigerant circulation circuit such that a high temperature refrigerant flowing through the high temperature refrigerant flow passage (RH) is expanded with reduced pressure into a low temperature refrigerant which then flows through the low temperature refrigerant flow passage (RC).

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 plate heat exchanger suitable for producing supercooled water in a regenerative air conditioner or the like.

[0002]

2. Description of the Related Art Conventionally, in view of reducing power demand at the time of peak cooling load and expanding power demand at off-peak time, slurry-like ice for use as cooling heat at the time of peak cooling load is cooled. 2. Description of the Related Art A regenerative air conditioner that is generated during off-peak loads and stored in a thermal storage tank is known.

As an example of this type of regenerative air conditioner, a refrigerant circulation circuit in which a compressor, a condenser, an expansion mechanism and a shell-and-tube type supercooling heat exchanger are sequentially connected by refrigerant piping, and a water circulation circuit And those with

As a water circulation circuit, for example, FIG.
As shown in (a), pump (a), preheater (b), stirrer (c), subcooling heat exchanger (d), subcooling eliminator (e), and heat storage tank (f)
Are sequentially connected by a water pipe.

[0005] In the ice making operation of this type of heat storage type air conditioner, first, water mixed with ice nuclei flowing out from the heat storage tank (f) to the water pipe is heated by the preheater (b) to remove the ice nuclei. Thaw.
Further, this water is further stirred by the stirrer (c), so that only the water containing no ice nuclei is obtained. Thereafter, the water is heat-exchanged with the refrigerant in the subcooling heat exchanger (d) to cool the water to a supercooled state. Then, after the supercooled state is eliminated in the supercooling canceller (e) to generate slurry ice, the ice is supplied to the heat storage tank (f) and stored.

In this regenerative air conditioner, since the ice nuclei do not flow into the supercooling heat exchanger (d) due to the above-described configuration, the flow passage is blocked due to freezing in the heat exchange unit of the heat storage medium. Hateful.

[0007]

However, the above-described regenerative air conditioner has the following problems.

That is, in addition to the subcooling heat exchanger (d), a preheater
Since it is necessary to separately provide (b) and the stirrer (c), there is an inconvenience that the installation space of the water circulation circuit is increased, and the size of the entire regenerative air conditioner is increased. Therefore, it is conceivable to reduce the size of the entire apparatus by using a compact plate heat exchanger, but there is a limit in reducing the size of the heat exchanger itself.

Further, the water circulation circuit is complicated, and the reliability of the regenerative air conditioner may be impaired.

[0010] Furthermore, the preheater (b), the stirrer (c), and the water pipe connecting them have a problem that the cost of the regenerative air conditioner increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a plate heat exchanger capable of reducing the size and cost of a regenerative air conditioner or the like. It is in.

[0012]

In order to achieve the above object, according to the present invention, in a plate type heat exchanger, a preheating section for heating a heat storage medium and a cooling section for cooling the heat storage medium are integrally formed. It was decided to.

More specifically, the means of the first aspect of the present invention comprises a heat storage medium flow passage (W) through which a heat storage medium flows, and a heat exchange medium between the stacked heat transfer plates (P1 to P5). In a plate heat exchanger that forms a heat exchange medium flow passage (R) through which a medium flows and exchanges heat between the heat storage medium and the heat exchange medium, the heat exchange medium flow passage (R) includes a heat transfer plate. (P1 ~ P
A high-temperature fluid flow path (RH) and a low-temperature fluid flow path (RC) are defined in a separation section (85) in the middle of 5), and one side of the separation section (85) has a high-temperature fluid path (RH). In the preheating section (53), the other side is configured as a cooling section (54) having a low-temperature fluid flow path (RC), and the heat storage medium flow path (W) extends from the preheating section (53) to the cooling section (54). While the heat storage medium flows from the preheating section (53) to the cooling section (54), while the high-temperature fluid flow passage (RH) flows a high-temperature fluid that is a heat exchange medium having a higher temperature than the heat storage medium, The low-temperature fluid flow passage (RC) has a configuration in which a heat exchange medium that cools the heat storage medium to a supercooled state flows.

[0014] According to the above aspect of the invention, the preheating section (53) for heating the heat storage medium and the cooling section (54) for cooling the heat storage medium can be integrally formed. Therefore, in combination with the downsizing of the heat exchanger itself, the installation space of the heat storage medium circulation circuit (30) can be reduced, and the heat storage type air conditioner
(10) The overall size can be made compact.

On the other hand, in the plate type heat exchanger according to the first aspect, the refrigerant circulated through the high-temperature fluid flow passage (RH) and the low-temperature fluid flow passage (RC) is provided. The circuit (20) is connected, and the refrigerant flowing out of the high-temperature fluid flow path (RH) lowers in temperature and flows into the low-temperature fluid flow path (RC).

According to the above-mentioned invention specific matter, the heating of the heat storage medium in the preheating section (53) and the cooling of the heat storage medium in the cooling section (54) are performed by the refrigerant circulating in the same refrigerant circulation circuit (20). Therefore, the size of the apparatus can be further reduced.

According to a third aspect of the present invention, there is provided a plate heat exchanger according to the first aspect, further comprising a separating portion for separating the high-temperature fluid flow passage (RH) and the low-temperature fluid flow passage (RC). (85)
Is configured to include a partition (87, 89) provided with a heat insulating means (86).

According to the above-mentioned specific features of the invention, wasteful heat exchange is not performed between the high-temperature fluid in the high-temperature fluid flow passage (RH) and the refrigerant in the low-temperature fluid flow passage (RC), and no heat loss occurs.

In the plate heat exchanger according to the first aspect of the present invention, the heat storage medium is located in the downstream side in the heat storage medium flow passage (W). Low turbulence area (54
b) and a configuration in which a high turbulence region (54a) that is located upstream of the low turbulence region (54b) and disturbs the flow of the heat storage medium more than the low turbulence region (54b) is formed. It is what it was.

According to the above-mentioned specific features of the present invention, the heat storage medium can be supercooled in a state where the turbulence of the flow is small, and freezing of the heat storage medium due to the stirring action can be reliably avoided.

According to a fifth aspect of the present invention, in the plate heat exchanger according to the fourth aspect, the highly turbulent region (54a) is formed in the heat transfer plates (P1 to P5). The heat transfer plate (P1 ~ P5) consists of a herringbone type projection row (81a, 81b) extending in a direction at a predetermined angle to the longitudinal direction of the heat transfer plate (P1 ~ P5), the low turbulence region (54b), the heat transfer plate (P1 ~ P5). P5) is formed by a linearly extending projection row (81c) formed in P5).

According to the above-mentioned invention specifying matter, the highly turbulent region (5
4a) and the low turbulence region (54b) can be configured easily and reliably.

[0023]

Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

-Heat-storage type air conditioner (10)-First, a heat-storage type air conditioner (10) using the heat exchanger (50) of the present invention will be described.

As shown in FIG. 1, a regenerative air conditioner (1
0) includes a refrigerant circuit (20) in which a refrigerant circulates, and a water circuit (30) in which water as a heat storage medium circulates. At the beginning,
The refrigerant circuit (20) and the water circuit (30) will be described in order.

-Refrigerant circuit (20)-The refrigerant circuit (20) comprises a compressor (21) and a four-way switching valve (22).
And the outdoor heat exchanger (23), the outdoor electric expansion valve (EV-1), the indoor electric expansion valve (EV-2), the indoor heat exchanger (24), and the accumulator (25) A main refrigerant circuit (27), which is connected in sequence by (26) and is capable of reversible operation, is provided. And the indoor heat exchanger (24) and the indoor electric expansion valve (EV-2)
Is provided in the indoor unit, while other component devices such as the compressor (21) are provided in the outdoor unit.

Further, the refrigerant circulation circuit (20) is provided with a heat storage refrigerant circuit (2a), a seed ice generation circuit (2b), and a hot gas passage (2c). The heat storage refrigerant circuit (2a) is a circuit in which the refrigerant circulates during a cold storage operation or a cooling operation using cold storage described below, and has one end having an outdoor heat exchanger (23) and an outdoor electric expansion valve (EV- The other end is connected between the four-way switching valve (22) and the accumulator (25). In the heat storage refrigerant circuit (2a), the first solenoid valve (SV-1) and the subcooling heat exchanger (5
0) and a heat storage electric expansion valve (EV-
3), the subcooling generator (54) of the subcooling heat exchanger (50), and the second
The solenoid valve (SV-2) is connected in order.

The seed ice generating circuit (2b) includes a water circulating circuit described later.
A circuit for generating seed ice in (30), one end of which is a subcooling generator (54) of a heat storage electric expansion valve (EV-3) and a supercooling heat exchanger (50) in a heat storage refrigerant circuit (2a). ), The other end is connected between the subcooling heat exchanger (50) and the second solenoid valve (SV-2), and the capillary tube (CP) and the seed ice generator (13)
Are sequentially connected.

The hot gas passage (2c) allows the refrigerant discharged from the compressor (21) to cool the supercooled heat exchanger (50) during a cooling operation utilizing cold storage.
One end is connected to the discharge side of the compressor (21), the other end is connected between the subcooling heat exchanger (50) and the second solenoid valve (SV-2), Equipped with a solenoid valve (SV-3).

-Water circulation circuit (30)-The water circulation circuit (30) comprises a heat storage tank (31) as shown in FIG.
Pump (32), subcooling heat exchanger (50), and subcooling canceller (3
And 4) are sequentially connected by a water pipe (35) so that circulation of water as a heat storage medium is possible.

The seed ice generator (13) is attached to the water pipe (35) at the downstream side of the subcooling heat exchanger (50), and is connected to the water pipe (3).
A part of the water flowing through 5) is cooled and iced by the refrigerant in the refrigerant circulation circuit (20), and is supplied as seed ice toward the supercooling canceller (34).

The supercooling canceller (34) is formed of a hollow cylindrical container, and is configured so that water introduced in a tangential direction forms a swirling flow. The supercooling canceller (34) agitates the seed ice generated by the seed ice generator (13) and the supercooled water generated by the supercooled heat exchanger (50) to eliminate supercooling. It is configured as follows.

-Supercooling heat exchanger (50)-Next, the supercooling heat exchanger (50) will be described.

As shown in the exploded perspective view of FIG. 3, the subcooling heat exchanger (50) is a plate type heat exchanger. In the supercooling heat exchanger (50), a plurality of heat transfer plates (63 to 66) are overlapped between two frames (61, 62), and a fluid is interposed between the heat transfer plates (63 to 66). Passages (W, RC, RH) are formed.

The heat transfer plates (63 to 66) are formed by forming a metal flat plate into a corrugated shape by press working. Further, these heat transfer plates (63 to 66) are composed of a first type heat transfer plate (P1) and a second type heat transfer plate (P2) having different wave shapes, and this plate type heat exchanger ( Five
No. 0) is configured such that these heat transfer plates (P1, P2) are alternately overlapped and integrally joined by brazing, welding, or the like.

First, the first type heat transfer plate (P1) will be described. As shown in FIG. 4, the first type heat transfer plate (P1) is provided with openings (71, 72) near the upper end and near the lower end, respectively, serving as outflow / inflow ports of water. In the center, a preheating section (53) is located above, and a supercooling section (5) is located below.
4) is formed respectively. In the corner of the preheating section (53),
While two openings (73, 74) located diagonally are provided, two openings (75, 76) located diagonally are also provided at the corners of the supercooling generator (54). And each opening
Seal portions (73a to 76a) are formed around (73 to 76).

The surfaces of the preheating section (53) and the supercooling generation section (54) are respectively corrugated, and have peaks (bold lines in FIG. 4) and valleys (thin lines in FIG. 4) that form waves. )
Are alternately formed. This wave shape will be described in detail. As in the case of the conventional heat transfer plate, the upstream slope portion (the upper slope portion is disposed such that the extension direction of the peak portion and the valley portion is inclined upward toward the right in FIG. 4. 81a) and a downstream inclined portion (81b) arranged so as to incline downward have a so-called herringbone shape.

As shown in FIG. 5, the second type of heat transfer plate (P2) is composed of a first type of heat transfer plate (63, 65).
Similarly to the above, openings (71 to 76) are provided at predetermined positions. That is, openings (71, 72) serving as water outflow and inlet ports at the upper and lower portions, and two openings (73, 74) located diagonally at the corners of the preheating portion (53), a supercooling generation portion ( Two openings (75, 76) located diagonally are also provided at the corners of 54). In addition, seal portions (71a, 72a) are formed around the openings (71, 72). And preheating part (53)
The supercooling generator (54) has a wavy shape.
However, the wave shape of the second type heat transfer plate (P2) is different from the wave shape of the first type heat transfer plate (P1).

Specifically, the heat transfer plate of the second type (P
The wave shape of 2) is formed in a herringbone shape,
The direction of extension of peaks and valleys is the first type of heat transfer plate (P1)
Is different. That is, as described above, in the first type heat transfer plate (P1), a herringbone shape is formed in the order of the downstream inclined portion (81b) and the upstream inclined portion (81a) from the left end as shown in FIG. On the other hand, in the heat transfer plate (P2) of the second type, as shown in FIG. 5, a herringbone shape is formed in the order of the upstream inclined portion (81a) and the downstream inclined portion (81b) from the left end. Have been.

Next, the arrangement of the heat transfer plates (63 to 66) will be described with reference to FIGS. The first plate (63) composed of the first type of heat transfer plate (P1) is provided with a seal (73a to 76a) protruding toward the frame (61) abutting against the frame (61), whereby each opening ( 73 to 76) are joined to the frame (61) with the periphery thereof sealed.
That is, between the frame (61) and the heat transfer plate (63),
Water can flow between the opening (71) and the opening (72).

Next to the first plate (63), a second plate (64) made of a second type of heat transfer plate (P2) is provided. The first plate (63) and the second plate (64) are formed by sealing portions (71a, 72a) protruding in directions facing each other.
Are in contact with each other so that the periphery of the opening (71, 72) is sealed. The partition (85) formed so as to protrude from each other forms a separation portion, and the partition (8)
By contacting 5) with each other, a preheating section (53) and a subcooling generation section (54) are defined, and their areas are separated from each other. That is, the refrigerant can flow between the opening (73) and the opening (74), and between the opening (75) and the opening (76). It is formed so as not to mix.

Further, next to the second plate (64), a third plate (65) made of a first type heat transfer plate (P1) is provided. The third plate (65) and the second plate (64) are provided with sealing portions (73a to 76a) protruding in directions facing each other.
Are brought into contact with each other so as to seal around the openings (73 to 76). Further, since the partition part (85) does not abut between the third plate (65) and the second plate (64), water can flow between the opening (71) and the opening (72). Has become.

In this manner, as shown in FIG. 6, the first and second heat transfer plates (P1, P2) are formed with flow paths (W, RH, RC) through which water and refrigerant flow, respectively. One type of heat transfer plate (P1) and the second type of heat transfer plate (P2) are alternately laminated, and these are integrated by brazing. This brazed portion is connected to each of the seal portions (71a to 76
a), the peripheral portion of the partition (85) and each of the heat transfer plates (63 to 66).

Next, the overlapping state of the heat transfer plates (63 to 66) in the preheating section (53) and the supercooling generation section (54) will be described. As shown in FIG. 7, for example, a flow path formed between the first plate (63) and the second plate (64) has a region close to the first plate (63) in the flow path cross section (FIG. 7). The upper part of the first plate (64) is configured to flow along the extending direction of the peak of the first plate (63) while climbing over the peak of the second plate (64). On the other hand, the second
Fluid flowing in a region near the plate (64) (a lower region in FIG. 7) passes over a valley (a downwardly protruding portion) of the first plate (63), and a peak of the second plate (64). It flows along the extension direction of the part.

As described above, a corrugated flow path is formed between the heat transfer plates (63 to 66). Therefore, the supercooling heat exchanger (50) is configured such that the fluid flows in each flow path in a state where the flow is largely disturbed.

The frames (61, 62) are joined to both ends of the plurality of heat transfer plates (P1, P2) stacked as described above. Each of the openings (61) is provided on one frame (61).
Pipes (91 to 96) are connected corresponding to (71 to 76). That is, the water inlet pipe (91) is located at the position corresponding to the opening (71),
A water outlet pipe (92) is provided at a position corresponding to the opening (72). Further, the opening (73), the opening (74), the opening (75), the opening (7
In the position corresponding to 6), the preheating section inlet piping (93),
A preheating section outlet pipe (94), a supercooling section inlet pipe (95), and a supercooling section outlet pipe (96) are provided.

With such a configuration, the water flow passages (W) and the refrigerant flow passages (R), which are heat exchange medium flow passages, are alternately formed between the heat transfer plates (P1, P2). . Further, in the refrigerant flow path (R), two separated flow paths of a high-temperature refrigerant flow path (RH) and a low-temperature refrigerant flow path (RC), which are high-temperature fluid flow paths, are formed.

That is, the water flows through the water inlet pipe (91) and from the opening (71) through the water flow passage as indicated by the dashed arrow in FIG.
(W), flows through the water flow passage (W), and then is discharged from the water outlet pipe (92) through the opening (72).
On the other hand, the high-temperature refrigerant flows from the opening (73) through the preheating unit inlet pipe (93) through the opening (73) as indicated by a solid line arrow in FIG.
(RH), flows through the high-temperature refrigerant flow passage (RH), and then opens
After (74), it is derived from the preheating section outlet pipe (94). Also, the low-temperature refrigerant passes through the supercooling section inlet pipe (95) and opens (7), as also indicated by the solid arrow in FIG.
5) into the low-temperature refrigerant flow passage (RC).
C), and then through the opening (76), the supercooling section outlet piping (9
It is derived from 6).

-Operation- Next, the operation of the regenerative air conditioner (10) will be described.

-Cold heat storage operation- In this operation mode, as shown in FIG.
2) is switched to the solid line side, and the heat storage electric expansion valve (EV-3) is adjusted to a predetermined opening degree, while the other electric expansion valves (EV-1, EV-2)
Is closed. In addition, the first and second solenoid valves (SV-1, SV-2)
Is open, and the third solenoid valve (SV-3) is closed.

In this state, in the refrigerant circulation circuit (20), the gas refrigerant discharged from the compressor (21) exchanges heat with the outside air in the outdoor heat exchanger (23) as shown by the arrow in FIG. Condense. Thereafter, after passing through the first solenoid valve (SV-1), the refrigerant flows into the high-temperature refrigerant flow passage (RH) from the preheating unit inlet pipe (93) of the subcooling heat exchanger (50).

The high-temperature liquid refrigerant flowing into the high-temperature refrigerant flow passage (RH) heats the water flowing through the water flow passage (W) located in the preheating section (53). Then, it passes through this high-temperature refrigerant flow passage (RH),
Subcooling heat exchanger (50) after passing through preheating section outlet pipe (94)
After flowing out of the chamber, it is decompressed and expanded by the heat storage electric expansion valve (EV-3) to lower the temperature and become a low-temperature two-phase refrigerant. Thereafter, the refrigerant flows into the low-temperature refrigerant flow passage (RC) via the subcooling section inlet pipe (95) of the subcooling heat exchanger (50). Therefore, the supercool generation unit (54)
While evaporating while cooling the water flowing through the water flow passage (W) located in the supercooled state (for example, −2 ° C.). Then, the evaporated refrigerant flows out of the subcooling heat exchanger (50) via the subcooling unit outlet pipe (96).

Thereafter, the refrigerant is supplied to the accumulator (25).
Is sucked into the compressor (21).

In this operation, a part of the refrigerant is
After being diverted from the downstream side of the heat storage electric expansion valve (EV-3) to the seed ice circuit (2b), the pressure is reduced by the capillary tube (CP), and the pressure is reduced by the seed ice generator (13), and the accumulator (25) is removed. Via compressor
Inhaled in (21). In the seed ice generator (13), the refrigerant exchanges heat with water flowing through the water pipe (35), and removes ice blocks from the water pipe (3).
Generated on the inner wall of 5).

On the other hand, in the water circulation circuit (30), the pump (32) is driven to circulate water as a heat storage medium.
The water flowing out of the heat storage tank (31) flows into the water flow passage (W) of the subcooling heat exchanger (50) from the water inlet pipe (91) via the pump (32).

Then, the water flows from the opening (71) to the preheating section (53), the supercool generation section (54), and the opening (72) in this order. At this time, in the preheating section (53), the high-temperature refrigerant flow passage (RH)
Is heated by a high-temperature refrigerant flowing through the water, and becomes a state of only water without ice nuclei. In other words, if the subcooling heat exchanger (5
Even if ice nuclei are mixed in (0), this ice nucleus
At this time, the mixture is heated and melted, and the incorporation of ice nuclei into the supercooling generator (54) is avoided. Then, the water that has passed through the preheating section (53) is cooled by exchanging heat with the low-temperature refrigerant flowing through the low-temperature refrigerant flow passage (RC) in the supercooling generation section (54), and enters a predetermined supercooling state. It flows out of the subcooling heat exchanger (50) from the outlet pipe (92).

The supercooled water flowing out of the subcooling heat exchanger (50) is further cooled in the seed ice generator (13), and generates seed ice on the inner wall surface of the water pipe (35). Thereafter, ice chips are generated around the seed ice, and the supercooled water containing the ice chips is supplied to the subcooling canceller (34). Then, in the subcooling canceller (34), the ice pieces and the supercooled water are stirred, and slurry-like ice for heat storage is generated and collected and stored in the heat storage tank (31).

As described above, the cold storage operation using the supercooling heat exchanger (50) is performed.

Next, another operation of the regenerative air conditioner (10) will be schematically described.

-Normal Cooling Operation- In this operation mode, only the refrigerant circuit (20) is operated. In this operation mode, the four-way switching valve (22) is switched to the solid line side in FIG. 1, the indoor electric expansion valve (EV-2) is superheated, and the outdoor electric expansion valve (EV-1) is fully opened. Then, the heat storage electric expansion valve (EV-3) is controlled to a fully closed state. On the other hand, each solenoid valve (SV-
1, SV-2 and SV-3) are both closed.

In this state, the gas refrigerant discharged from the compressor (21) exchanges heat with the outside air in the outdoor heat exchanger (23) and condenses. After that, the refrigerant is decompressed by the indoor electric expansion valve (EV-2) to become a two-phase refrigerant, and then is evaporated by the indoor heat exchanger (24), and passes through the accumulator (25) to the compressor (21). Inhaled. This circulation operation cools the room.

-Cooling / Heat Storage Cooling Operation- In this operation mode, as shown in FIG.
2) is switched to the solid line side, the indoor electric expansion valve (EV-2) is controlled to a predetermined opening, and the other electric expansion valves (EV-1, EV-3) are fully opened. Also, the first and third solenoid valves (SV-1, SV-3) are open,
The second solenoid valve (SV-2) closes.

In this state, in the water circulation circuit (30),
The pump (32) is driven to circulate cold water. After passing through the pump (32), the cold water in the heat storage tank (31) flows into the water flow passage (W) of the subcooling heat exchanger (50). Then, the high-temperature refrigerant passing through the preheating unit (53) and the supercooling generation unit (54) and flowing through the high-temperature refrigerant flow passage (RH) and the low-temperature refrigerant flow passage (RC) is cooled, and is heated. Thereafter, the heated water flows out of the subcooling heat exchanger (50), passes through the subcooling canceller (34), and returns to the heat storage tank (31). Then, the heated water exchanges heat with ice stored in the heat storage tank (31) to be cooled, becomes cold water, and returns to the heat storage tank (3).
It flows out of 1) and circulates in the water circulation circuit.

On the other hand, in the refrigerant circuit (20), a part of the gas refrigerant discharged from the compressor (21) passes through the four-way switching valve (22) as shown by the arrow in FIG. Outdoor heat exchanger
It flows to (23) and condenses by exchanging heat with the outside air in the outdoor heat exchanger (23). Further, other discharged refrigerant flows through the low-temperature refrigerant flow path (RC) and the high-temperature refrigerant flow path (RH) of the subcooling heat exchanger (50) via the hot gas path (2c), and flows through the water circulation circuit (30). It exchanges heat with the circulating cold water to condense. And the outdoor heat exchanger (23)
The refrigerant condensed in the supercooling heat exchanger (50) merges and is decompressed by the indoor electric expansion valve (EV-2), and then evaporates in the indoor heat exchanger (24) to cool the indoor air. Is sucked into the compressor (21) through the accumulator (25).

With the above operation, the indoor cooling operation using the cold heat of the ice stored in the heat storage tank (31) is performed.

-Normal Heating Operation- In this operation mode, only the refrigerant circulation circuit (20) is operated. In this operation mode, the four-way switching valve (22) is switched to the broken line in FIG. 1, the outdoor electric expansion valve (EV-1) is controlled to a predetermined opening, and the indoor electric expansion valve (EV-2) is fully opened. Then, the heat storage electric expansion valve (EV-3) is controlled to a fully closed state. On the other hand, each solenoid valve (SV-1,
SV-2 and SV-3) are both closed.

In this state, the gas refrigerant discharged from the compressor (21) flows into the indoor heat exchanger (24), exchanges heat with the indoor air, condenses, and heats the indoor air. Thereafter, the refrigerant is reduced in pressure by the outdoor electric expansion valve (EV-1) to become a two-phase refrigerant, and then exchanges heat with the outside air in the outdoor heat exchanger (23) to evaporate. After that, the refrigerant passes through the accumulator (25) and the compressor (2
Inhaled in 1). The room is heated by such a circulation operation of the refrigerant.

The operation of the regenerative air conditioner (10) has been described above.

As described above, according to the present invention, the regenerative air conditioner (10) can be made compact by using a plate heat exchanger for the subcooling heat exchanger (50).

Further, the subcooling heat exchanger (50) of the present invention
According to the preheating unit (53) that heats the water containing ice nuclei in the plate heat exchanger to melt the ice nuclei, and a supercooling generation unit (54) that cools the water to a supercooled state By integrally providing, the size of the water circulation circuit (30) can be reduced. Therefore, the installation space for the water circulation circuit (30) can be reduced, so that the entire regenerative air conditioner (10) can be made compact.

Further, since it is not necessary to separately provide a preheater and a water pipe for connecting the preheater which were conventionally required, the configuration of the water circulation circuit (30) can be further simplified, The reliability of the heat storage type air conditioner (10) can be improved.

Further, the cost of the regenerative air conditioner (10) can be reduced.

In the first embodiment, the high-temperature refrigerant flow passage
Although (RH) and the low-temperature refrigerant flow passage (RC) are connected to the same refrigerant circuit (30), they may be connected to separate circuits. That is, a fluid circuit through which a high-temperature fluid such as hot water or brine flows may be connected to the high-temperature refrigerant flow passage (RH), while a refrigerant circulation circuit may be connected to the low-temperature refrigerant flow passage (RC).

[0074]

Embodiment 2 The heat exchanger of Embodiment 2 is different from the plate heat exchanger of Embodiment 1 in that the heat transfer plate (P
Instead of (1, P2), a heat transfer plate (P3) shown in FIG. 10 and a heat transfer plate (P4) shown in FIG. 11 are used.

In the heat transfer plates (P3, P4) of the second embodiment,
The wave shape in the supercooling generation part (54) is different between the upstream part (54a) and the downstream part (54b). The wave shape of the upstream portion (54a) is the same as that of the heat transfer plate (P1, P2) in the first embodiment, but the wave shape of the downstream portion (54b) is such that the extension direction of the peaks and valleys is vertical. It has become. In addition, this upstream part (5
At the boundary portion between 4a) and the downstream portion (54b), the corrugated sheet is bent so that the peaks and valleys are continuous.

The first heat transfer plate (P3) and the second heat transfer plate (P4) are connected to the preheating portion (53) and the upstream portion (54a) of the supercooling generation portion in the first embodiment. 1 Heat transfer plate
Like (P1) and the second heat transfer plate (P2), they are formed such that their peaks and valleys are in contact with each other and their extending directions intersect. On the other hand, the downstream part (5
In 4b), the first heat transfer plate (P3) and the second heat transfer plate (P4) are formed such that their peaks and valleys are in contact with each other, and their extending directions match.

With such a configuration, in the plate heat exchanger of the second embodiment, the fluid (refrigerant, water) has a waveform in the preheating section (53) and the upstream side (54a) of the supercooling generation section. Since the gas flows through the flow channel, the turbulence is large. On the other hand, on the downstream side (54b) of the supercooling generation section, the fluid flows through a linear flow path, so that the flow becomes less turbulent.

Therefore, in the plate heat exchanger according to the second embodiment, a high turbulence region is formed in the upstream portion (54a) of the subcooling generation portion to make the flow of water large, and the downstream portion (54a) is formed. Since a low turbulence region for reducing turbulence in the flow of water is formed in 54b), heat transfer between water and the refrigerant is as follows.

That is, in the preheating section (53), since both the refrigerant and the water flow in a state of great turbulence, heat exchange is performed at a high heat transmission rate and the flow is well stirred, so that the heat exchanger The ice nuclei mixed in the melt reliably melt with a small amount of heat.

Also, in the upstream portion (54a) of the supercool generation section, since the water and the refrigerant flow in a state of large turbulence, that is, in a turbulent state, the water is rapidly cooled, and the upstream portion (54a) is cooled. Predetermined temperature that does not freeze in (54a) (for example, 0 ° C)
Cooled down.

Then, the refrigerant and water flowing out of the upstream portion (54a) respectively flow into the downstream portion (54b), and perform heat exchange in the downstream portion (54b). This downstream part
In (54b), since the heat transmission coefficient is not as high as in the upstream portion (54a), the water is gradually cooled. Then, the water is cooled to a predetermined degree of supercooling (for example, −2 ° C.) in the upstream portion (54b). The supercooled water flows out of the supercooling heat exchanger (50) in a rectified state with little disturbance.

As a result, the heat exchanger of the second embodiment has the following effects in addition to the effects described in the first embodiment.

As described above, the downstream portion of the supercool generation section
In (54b), since the flows of the water and the refrigerant are rectified, the supercooled state of the water due to the stirring action is hardly eliminated. Therefore, generation of freezing in the heat exchanger can be avoided, and a stable supercooled water generation operation can be performed. In addition, since there is no significant fluctuation in water temperature in the downstream side (54b), the heat exchanger (5
The temperature of the water taken out from 0) can be set relatively easily.

[0084]

Third Embodiment In the plate heat exchanger of the third embodiment, a heat insulating means (86) is applied to the partition (85) of the plate heat exchanger of the first or second embodiment. .

More specifically, in the third embodiment, as shown in FIG. 12, a heat transfer material in which a heat insulating material (87) separates a high-temperature refrigerant flow passage (RH) and a low-temperature refrigerant flow passage (RC) is used. A plate (P5) is used.

Therefore, in the plate heat exchanger of the third embodiment, heat exchange between the high-temperature refrigerant flowing through the high-temperature refrigerant flow passage (RH) and the low-temperature refrigerant flowing through the cold-temperature refrigerant flow passage (RC) is small. Therefore, heat loss due to wasteful heat exchange between the high-temperature refrigerant and the low-temperature refrigerant is small, and the performance of the regenerative air conditioner is improved.

The heat insulating means (86) for partitioning between the high-temperature refrigerant flow passage (RH) and the low-temperature refrigerant flow passage (RC) is provided by the heat insulating material (8).
It is not limited to 7). For example, in addition to the heat insulating material (87), as shown in FIGS. 13 (a) and (b), projecting portions (88a, 88b) arranged vertically in parallel with the partition (85) of each heat transfer plate. ) Is provided, and is joined to an adjacent heat transfer plate to form a partition space (89) between the heat transfer plates, and the partition space (89) is evacuated to form a heat insulating means (86). May be.

[0088]

As described above, according to the present invention, the following effects are exhibited.

According to the first aspect of the present invention, the heat storage medium flow passages and the heat exchange medium flow passages are alternately formed between the stacked heat transfer plates, and the high temperature fluid flow passages are further passed through the heat exchange medium flow passages. Since the passage and the low-temperature fluid flow passage are formed, the preheating unit that heats the heat storage medium and the cooling unit that cools the heat storage medium can be integrally formed. Therefore, the installation space for the heat storage medium circulation circuit can be reduced, and the overall size of the heat storage type air conditioner can be reduced. In addition, since it is not necessary to separately provide a preheater and a water pipe for connecting the preheater, which are conventionally required, the water circulation circuit can be simplified, and the reliability of the regenerative air conditioner can be improved. improves. Further, the cost of the heat storage type air conditioner can be reduced.

According to the second aspect of the present invention, the refrigerant circulating in the same refrigerant circulation circuit can heat the heat storage medium in the preheating section and cool the heat storage medium in the cooling section. A compact device can be achieved.

According to the third aspect of the present invention, the high-temperature fluid flow passage and the low-temperature fluid flow passage are separated by the partition provided with the heat insulating means. No wasteful heat exchange is performed with the refrigerant flowing through the low-temperature fluid flow passage, and no heat loss occurs. Therefore, an efficient supercooling generation operation can be performed.

According to the fourth aspect of the present invention, the upstream portion of the heat storage medium flow passage is a high turbulence region, and the downstream portion is a low turbulence region. Can be avoided. Further, the temperature change of the heat storage medium is reduced at the downstream side, and the temperature of the heat storage medium at the outlet of the heat exchanger can be easily adjusted. As a result, the supercool generation operation can be performed stably.

According to the fifth aspect of the present invention, the high turbulence region and the low turbulence region are formed by forming the high turbulence region with a herringbone type projection line and the low turbulence region with a linearly extending protrusion line. Can be easily and reliably formed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a refrigerant circulation circuit and a water circulation circuit of a regenerative air conditioner.

FIG. 2 is a diagram showing a water circulation circuit.

FIG. 3 is an exploded perspective view of the plate heat exchanger.

FIG. 4 is a front view of a first type heat transfer plate of the first embodiment.

FIG. 5 is a front view of a second type of heat transfer plate of the first embodiment.

FIG. 6 is a sectional view taken along line AA in FIG. 3;

FIG. 7 is a perspective view showing an overlapping state of the heat transfer plates.

FIG. 8 is a circuit diagram of the regenerative air conditioner during the cold regenerative operation.

FIG. 9 is a circuit diagram of the regenerative air conditioner during a cold storage operation.

FIG. 10 is a front view of a first type of heat transfer plate according to the second embodiment.

FIG. 11 is a front view of a second type of heat transfer plate of the second embodiment.

FIG. 12 is a front view of a heat transfer plate according to a third embodiment.

FIG. 13 is a view showing another heat exchanger according to the third embodiment;
(A) is a front view of a heat transfer plate, (b) is a cross-sectional view of a heat exchanger.

FIG. 14 is a diagram showing a water circulation circuit of a conventional regenerative air conditioner.

[Explanation of symbols]

 (50) Subcooling heat exchanger (53) Preheating section (54) Supercooling generation section (54a) High turbulence area (54b) Low turbulence area (71) to (76) Opening (81a) Upstream slope of projection row (81b) Downstream slope of projection row (87) Insulation material (89) Partition space (P1) Heat transfer plate of first type (P2) Heat transfer plate of second type (RC) Low-temperature refrigerant flow passage (RH) High-temperature refrigerant flow path (W) Water flow path

Claims (5)

[Claims] [Claim 1] Between stacked heat transfer plates (P1 to P5),
In a plate heat exchanger that forms a heat storage medium flow path (W) through which a heat storage medium flows, and a heat exchange medium flow path (R) through which a heat exchange medium flows, and performs heat exchange between the heat storage medium and the heat exchange medium. In the heat exchange medium flow path (R), a high temperature fluid flow path (RH) and a low temperature fluid flow path (RC) are defined by a separation part (85) in the middle of the heat transfer plates (P1 to P5). One side of the separation section (85) is configured as a preheating section (53) having a high-temperature fluid passage (RH), and the other side is configured as a cooling section (54) having a low-temperature fluid flow path (RC). The flow passage (W) extends from the preheating section (53) to the cooling section (54).
The heat storage medium continues from the preheating section (53) to the cooling section (54).
While flowing into the high-temperature fluid flow passage (RH), a high-temperature fluid as a heat exchange medium having a higher temperature than the heat storage medium flows, and the low-temperature fluid flow passage (R
A plate type heat exchanger characterized in that a heat exchange medium for cooling the heat storage medium to a supercooled state flows in C). 2. The plate heat exchanger according to claim 1, wherein the high-temperature fluid flow path (RH) and the low-temperature fluid flow path (RC) are connected to a refrigerant circuit (20), A plate type heat exchanger characterized in that the refrigerant flowing out of the RH) decreases in temperature and flows into the low-temperature fluid flow passage (RC). 3. The plate type heat exchanger according to claim 1, wherein the hot fluid flow passage (RH) and the cold fluid flow passage (RC) are separated from each other.
5) A plate heat exchanger comprising a partition (87, 89) provided with a heat insulating means (86). 4. A low turbulence region according to claim 1, wherein the heat storage medium flow path (W) is located downstream and allows the heat storage medium to flow without overcooling. (Five
4b) and a high turbulence region (54a) which is located upstream of the low turbulence region (54b) and disturbs the flow of the heat storage medium more than the low turbulence region (54b) is formed. The plate type heat exchanger characterized by the above-mentioned. 5. The plate heat exchanger according to claim 4, wherein the high turbulence region (54a) extends in a longitudinal direction of the heat transfer plates (P1 to P5) formed on the heat transfer plates (P1 to P5). Herringbone-type projection rows (81a, 81b) extending in a direction at a predetermined angle with respect to
Wherein the low turbulence region (54b) is formed by a linearly extending projection row (81c) formed on the heat transfer plates (P1 to P5).