JP2003329378A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a miniaturizable and compactly constructible heat exchanger for reducing a pressure loss. <P>SOLUTION: This heat exchanger uses a plurality of porous flat tubes 222 formed by extrusion molding as a tube for flowing a high pressure refrigerant, and has a header tank 225 for communicating with the inside of the plurality of porous flat tubes 222, and distributing-supplying the high pressure refrigerant to the plurality of porous flat tubes 222, and a header tank 226 for communicating with the inside of the plurality of porous flat tubes 222, and collecting- recovering the high pressure refrigerant flowing out of the plurality of porous flat tubes 222. The high pressure refrigerant is made to flow in parallel in the plurality of porous flat tubes 222. Thus, the heat exchanger 220 is miniaturized and compactly constituted by forming a passage of the high pressure refrigerant in a multilayer (multi-path) shape. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger for exchanging heat between a first fluid such as water or brine (heat exchange medium) and a second fluid such as carbon dioxide refrigerant having a pressure higher than a critical pressure. In particular, the present invention relates to miniaturization and size reduction of heat exchangers and reduction of pressure loss of both fluids.

[0002]

2. Description of the Related Art FIG. 9 shows a conventional heat exchanger (a).
Is a side view and (b) is a front view. It is a refrigerant / water heat exchanger (radiator) that exchanges heat between the refrigerant discharged from the compressor and having a pressure higher than the critical pressure and water. This water heat exchanger 22
0 is a water tube 22 through which water flows, as shown in FIG.
1 is a counterflow type heat exchanger configured such that the refrigerant flow and the hot water supply water flow are opposed to each other by bringing 1 and a plurality of refrigerant tubes 222 through which the refrigerant flows into contact with each other.

Reference numeral 223 is a pipe for supplying water to the water tube 221, 224 is a pipe for collecting water flowing out from the water tube 221, and 225 is a pipe for distributing and supplying a refrigerant to a plurality of refrigerant tubes 222. 3 is a header tank, and 226 is a fourth header tank that collects and collects the refrigerant that has flowed out from the plurality of refrigerant tubes 222.

[0004]

As described above, in the prior art, more water / brine passages and more high-pressure refrigerant passages are joined for heat exchange, but the area occupied by the heat exchanger becomes large. However, there is a problem that the pressure loss of both fluids becomes large. The present invention has been made in view of the above conventional problems, and an object of the present invention is to provide a heat exchanger that can be configured to be small and compact and can reduce pressure loss.

[0005]

The present invention employs the following technical means in order to achieve the above object. In the invention according to claim 1, the heat exchanger is a heat exchanger for exchanging heat between the first fluid and the second fluid having a critical pressure or more, and the second porous flat tube (22) formed by extrusion molding as a tube through which the second fluid flows.
A second header tank (225) that uses a plurality of 2) and communicates with the insides of the plurality of second perforated flat tubes (222) to distribute and supply the second fluid to the plurality of second perforated flat tubes (222). And a plurality of second perforated flat tubes (2
22) A plurality of second perforated flat tubes (2
22) and a fourth header tank (226) that collects and collects the second fluid that flows out from the second fluid, and the second fluid flows through the plurality of second perforated flat tubes (222) in parallel. .

In this way, the heat exchanger can be made compact by making the passage of the second fluid, which is a high-pressure refrigerant, multi-layered (multi-pass).
The structure can be made compact and the pressure loss can be reduced.

According to the second aspect of the invention, a plurality of first porous flat tubes (221e) formed by extrusion molding are used as the tubes through which the first fluid flows, and the plurality of first porous flat tubes (221e) are provided. A first header tank (223) that communicates with the first perforated flat tubes (221e) and supplies the first fluid to the first perforated flat tubes (221e); First of
It has a 2nd header tank (224) which collects and collects the 1st fluid which flows out from a porous flat tube (221e), and a plurality of 1st porous flat tubes (221e) and 2nd porous flat tubes (222) are alternated. It is characterized in that the core portion is formed by laminating one sheet.

As described above, the heat exchanger can be made compact and compact by combining the perforated flat tubes and making the both fluid passages multi-layered (multi-pass).
The pressure loss can also be reduced.

According to the third aspect of the invention, as the tube through which the first fluid flows, a pair of flat plates (221b, 221c) formed by press molding the tank portion (221d) and the fluid circulation portion (221) are used. In addition, a plurality of pairs of flat plates (221b, 221c) and second perforated flat tubes (222) are alternately laminated to form a core portion.

As described above, a pair of flat plates (221b, 221b, which are press-formed with passages for the first fluid such as water and brine).
221c) formed by stacking so-called Delon cup tubes and a perforated flat tube (222) formed by extrusion molding the passage of the second fluid, which is a high-pressure refrigerant, so-called extrusion tube, and both fluid passages are multi-layered. By making (multi-pass), the heat exchanger can be made compact and compact, and the pressure loss can also be reduced. Incidentally, the reference numerals in parentheses of the above-mentioned respective means are examples showing the corresponding relationship with the concrete means described in the embodiments described later.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) In this embodiment, the heat exchanger according to the present invention is applied to a domestic water heater, FIG. 1 is an external view of the water heater 100, and FIG. 2 is a hot water heater. It is a schematic diagram of the container 100. In FIG. 2, 200 (enclosed by a chain double-dashed line) is a supercritical heat pump cycle (hereinafter, abbreviated as heat pump) that heats the hot water to generate hot water at a high temperature (about 85 ° C. in this embodiment). .

The supercritical heat pump cycle is a heat pump cycle in which the pressure of the refrigerant on the high pressure side is equal to or higher than the critical pressure of the refrigerant, and is a heat pump cycle using carbon dioxide, ethylene, ethane, nitric oxide or the like as the refrigerant. Further, 300 is a plurality of heat retaining tanks for retaining warm water heated by the heat pump 200, and the respective heat retaining tanks 300 are arranged in parallel to the flow of hot water (hot water).

In FIG. 2, reference numeral 210 denotes a compressor for sucking and compressing a refrigerant (carbon dioxide in this embodiment).
Reference numeral 10 is an electric compressor in which a compression mechanism (not shown) for sucking and compressing the refrigerant and an electric motor (not shown) for driving the compression mechanism are integrated. The heat exchanger 220 according to the present invention is applied, and is a water heat exchanger (radiator) that exchanges heat between the refrigerant discharged from the compressor 210 and the hot water. Since it is an essential part of the present invention, its details will be described later.

Further, reference numeral 230 in FIG. 2 is an electric expansion valve (pressure reducer) for reducing the pressure of the refrigerant flowing out of the heat exchanger 220, and 240 is an electric expansion valve 230 (hereinafter, the expansion valve 23).
Abbreviated as 0. ) Is a vaporizer that evaporates the refrigerant flowing out from the above) to absorb the heat in the atmosphere into the refrigerant and also causes the refrigerant to flow toward an accumulator 250 (the suction side of the compressor 210) described later.

The reference numeral 250 separates the refrigerant flowing out of the evaporator 240 into a gas-phase refrigerant and a liquid-phase refrigerant to compress the gas-phase refrigerant into the compressor 2
It is an accumulator that stores the excess refrigerant in the heat pump 200 while flowing out to the suction side of 10. Reference numeral 260 denotes a blower that blows air (outside air) to the evaporator 240 and can adjust the amount of blown air. The blower 260, the compressor 210, and the expansion valve 230 are based on detection signals of each sensor described later. Electronic control unit (ECU) 2
It is controlled by 70.

271 is a refrigerant temperature sensor for detecting the temperature of the refrigerant flowing out of the heat exchanger 220.
Reference numeral 2 is a first hot water temperature sensor that detects the temperature of the hot water supplied to the heat exchanger 220. 273 is a water heat exchanger 220
Is a refrigerant pressure sensor for detecting the pressure of the refrigerant flowing out from the refrigerant (high-pressure side refrigerant pressure), and 274 is a second hot water temperature sensor for detecting the temperature of the hot water supplied from the water heat exchanger 220. The detection signals of the sensors 271 to 274 are input to the ECU 270.

Here, the refrigerant pressure on the high pressure side means the compressor 2
10 is the pressure of the refrigerant existing in the refrigerant passage extending from the discharge side of the expansion valve 230 to the inflow side of the expansion valve 230.
The discharge pressure is zero (the internal pressure of the water heat exchanger 220). On the other hand, the low-pressure side refrigerant pressure is the pressure of the refrigerant existing in the refrigerant passage extending from the outflow side of the expansion valve 230 to the suction side of the compressor 210, and the pressure is the suction pressure of the compressor 210 (evaporator 240 Internal pressure).

Numeral 400 is an electric water pump (hereinafter abbreviated as pump) which supplies (circulates) hot water to the water heat exchanger 220 and adjusts the amount of hot water supplied, and 410 is a water pipe ( It is a stop valve that prevents tap water supplied from (not shown) from flowing into the water heat exchanger 220. The pump 400 and the shutoff valve 410 are also EC
It is controlled by U270.

Next, the heat exchanger 220, which is an essential part of the present invention.
The structure of will be described. FIG. 3 is a perspective view of the heat exchanger according to the first embodiment of the present invention. Water as the first fluid flows through a case 227 that surrounds the heat exchanger 220 and is shown by a chain double-dashed line. Also, the second
A plurality of extruded tubes (perforated flat tubes) 222 formed by extrusion molding are used as tubes through which a high-pressure refrigerant of a fluid flows. In the present embodiment, three paths 222a to 222c are used to make three passes.

The extruded tubes 222a to 222c
The extruded tubes 222a to 222 from the header pipe (third header tank) 225 in which the ends of the
The high-pressure refrigerant is distributed and supplied into c, and the extruded tube 22
2a to 222c, while exchanging heat with water and then flowing out from the extruded tubes 222a to 222c, the other end of each extruded tube 222a to 222c is inserted into the brazed header pipe (the fourth pipe). Header tank) 22
Collected at 6

In this way, by making the passage of the second fluid, which is a high-pressure refrigerant, multi-layered (multi-pass), the heat exchanger can be made small and compact.
The structure can be made compact and the pressure loss can be reduced.

(Second Embodiment) FIG. 4 is a perspective view of a heat exchanger 220 according to a second embodiment of the present invention. Even if a plurality of extruded tubes are connected to one header pipe as in the first embodiment, the number of extruded tubes is limited to about three. Therefore, a header tank is provided for each extruded tube to aim for further multipass. It is a thing.

Water as the first fluid flows through the case 227 surrounded by the two-dot chain line surrounding the heat exchanger 220, as in the first embodiment. As the tube through which the high-pressure refrigerant of the second fluid flows, a plurality of extruded tubes (perforated flat tubes) 222 formed by extrusion molding are used. In this embodiment, 3 of 222d to 222f
The number of passes is 3 using a book, which is the same as that of the first embodiment, but it is possible to further increase the number of passes.

Then, a high pressure refrigerant is distributed and supplied from a distributor (not shown) to header pipes (third header tanks) 225a to 225c into which the respective ends of the extruded tubes 222d to 222f have been inserted and brazed, and the extruded tubes 222d to each other. Exchanges heat with water as it passes through ~ 222f. And each extruded tube 222d-22
The refrigerant flowing out from the header pipes (fourth header tanks) 226a to 226c into which the other ends of 2f are inserted and brazed is collectively collected by a distributor (not shown).

In this way, by making the passage of the second fluid, which is a high-pressure refrigerant, multi-layered (multi-pass), the heat exchanger can be made compact.
The structure can be made compact and the pressure loss can be reduced. Although omitted in FIG. 4 to simplify the drawing, fins may be inserted between the bent shapes of the extruded tubes 222d to 222f to increase the efficiency of heat exchange with water and brazed together. good.

(Third Embodiment) FIG. 5 is a perspective view of a heat exchanger 220 according to a third embodiment of the present invention. The water as the first fluid is the heat exchanger 22 as in the first embodiment.
It circulates in a case 227 indicated by a two-dot chain line that surrounds 0. Further, as the tubes through which the high-pressure refrigerant of the second fluid flows, a plurality of extruded tubes (perforated flat tubes) 222 formed by extrusion molding are used. In the present embodiment, 9 paths are used to make 9 passes.

Then, the header tank (third header tank) 2 in which the end of the extruded tube 222 is inserted and brazed
The high-pressure refrigerant is distributed and supplied from 25 to each extruded tube 222, heat-exchanges with water while passing through the extruded tube 222, and the refrigerant flowing out from the extruded tube 222 is the other end of each extruded tube 222. Are collected and collected in a header tank (fourth header tank) 226 which has been inserted and brazed.

Fins 228 for increasing the efficiency of heat exchange with water are inserted between the extruded tubes 222 and brazed together. In this way, the heat exchanger can be made compact and compact by making the passage of the second fluid that is the high-pressure refrigerant multi-layered (multi-pass), and the pressure loss can also be reduced.

(Fourth Embodiment) FIG. 6 is a perspective view of a heat exchanger 220 according to a fourth embodiment of the present invention. As the tube through which the high-pressure refrigerant of the second fluid flows, the above-mentioned third
As in the embodiment, each of the plurality of extruded tubes 222 and the header tanks 225 and 226 are configured. Besides,
In the above-described third embodiment, a plurality of extruded tubes (first perforated flat tubes) 229 formed by extrusion molding are used as tubes through which water flows in the portions where the water of the first fluid flows is the fins 228. There is.

Then, the header tank (first header tank) 2 in which the end portion of the extruded tube 229 is inserted and brazed
23, water is distributed and supplied into each extruded tube 229,
The water exchanging heat with the refrigerant passing through the inside of the extruding tube 222 while passing through the inside of the extruding tube 229, and the water flowing out from the extruding tube 229 afterwards exchanges with each extruding tube 229.
Is collected and collected in a header tank (second header tank) 224 brazed by inserting the other end thereof.

As described above, a plurality of perforated flat tubes are alternately laminated and combined, and both fluid passages are multi-layered (multi-pass), whereby the heat exchanger can be made compact and compact, and pressure loss can be reduced. Can also be reduced.

(Fifth Embodiment) FIG. 7 is a perspective view of a heat exchanger 220 according to a fifth embodiment of the present invention. Also,
FIG. 8 is a cross-sectional view taken along the line AA in FIG. 7, showing a cross section of both tubes of the heat exchanger 220. As the tube through which the high-pressure refrigerant of the second fluid flows, as in the third and fourth embodiments described above, a plurality of extruding tubes 222 and a header tank 22 are provided.
It is composed of 5,226. In addition, as shown in FIG. 8, as a tube through which the water of the first fluid flows, a pair of flat plates 221b and 221c formed by press forming are opposed to each other to form a fluid flow portion 221. There is.

The tank portion 223 for distributing and supplying water to each fluid circulating portion 221 and the tank portion 224 for collecting and collecting water flowing out from each fluid circulating portion 221 are also the flat plate 2
21b and 221c press-formed bowl-shaped portion 22
It is formed by overlapping 1d. Then, the pair of flat plates 221b and 221c and the extruding tube 222 through which the high-pressure refrigerant passes are alternately laminated to form a core portion.

As described above, the so-called drone cup tube, which is formed by the pair of flat plates 221b and 221c formed by press molding the passage of the first fluid, and the passage of the high-pressure refrigerant which is the second fluid are formed by extrusion. In combination with the porous flat tube 222, so-called extruded tube,
By making both fluid passages multi-layered (multi-pass), the heat exchanger can be made compact and compact, and the pressure loss can also be reduced.

In the above embodiment, the flat plate 2
The inside of the fluid circulation portion 221 of the drone cup tube formed by 21b and 221c has a flat shape, but inner fins may be inserted or a convex shape into the fluid circulation portion 221 may be formed. Is also good.

(Other Embodiments) In the above embodiments, the heat exchanger for exchanging heat between water and the refrigerant is applied, but the heat exchanger according to the present invention is not limited to this, and the first embodiment In addition to water, the fluid can be applied to a heat exchanger that exchanges heat with air, brine (heat exchange medium) such as antifreeze and ethylene glycol.

In the first and second embodiments, in order to make FIGS. 3 and 4 easier to see, the extruded tubes 222a to 222c and 22 are formed.
Although the fins between the bent shapes of 2d to 222f are omitted, as shown in FIG. 5 of the third embodiment, fins 228 for increasing the efficiency of heat exchange with water may be inserted and integrally brazed. On the contrary, in the third embodiment, the fin 228 may be omitted.

[Brief description of drawings]

FIG. 1 is an external view of a water heater according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a water heater according to an embodiment of the present invention.

FIG. 3 is a perspective view of a heat exchanger according to the first embodiment of the present invention.

FIG. 4 is a perspective view of a heat exchanger according to a second embodiment of the present invention.

FIG. 5 is a perspective view of a heat exchanger according to a third embodiment of the present invention.

FIG. 6 is a perspective view of a heat exchanger according to a fourth embodiment of the present invention.

FIG. 7 is a perspective view of a heat exchanger according to a fifth embodiment of the present invention.

FIG. 8 is a cross-sectional view taken along the line AA in FIG. 7, showing both tube cross sections of the heat exchanger.

FIG. 9 shows a conventional heat exchanger, (a) is a side view,
(B) is a front view.

[Explanation of symbols]

221 Fluid distribution section 221b Flat plate 221c Flat plate 221d tank part 221e Extruded tube (first perforated flat tube) 222 Extruded tube (second perforated flat tube) 223 First header tank 224 Second header tank 225 header pipe (3rd header tank) 226 header pipe (4th header tank)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F28F 9/26 F28F 9/26

Claims (3)

[Claims] 1. A heat exchanger for exchanging heat between a first fluid and a second fluid having a critical pressure or more, wherein a second porous flat tube (222) formed by extrusion molding is used as a tube through which the second fluid flows. A plurality of second porous flat tubes (22) are used while communicating with the insides of the plurality of second porous flat tubes (222).
3) a third header tank (225) for distributing and supplying the second fluid to 2), and the plurality of second perforated flat tubes (2)
22) and a fourth header tank (226) that communicates with the inside of the second perforated flat tubes (222) and collects and collects the second fluid. Second perforated flat tube (2
22) are distributed in parallel. 2. A first porous flat tube (221e) formed by extrusion as a tube through which the first fluid flows.
And a plurality of the first perforated flat tubes (221e), the first header tank (223) that communicates with the inside of the plurality of the first perforated flat tubes (221e) to supply the first fluid by distribution. ) And the plurality of first perforated flat tubes (221e) are communicated with each other, and the first plurality of first perforated flat tubes (221e) flow out from the plurality of first perforated flat tubes (221e).
A second header tank (224) that collects and collects a fluid is provided, and a plurality of the first porous flat tubes (221e) and the second porous flat tubes (222) are alternately laminated to form a core portion. The heat exchanger according to claim 1, wherein the heat exchanger is a heat exchanger. 3. A pair of flat plates (221b, 221b) formed by press molding a tank portion (221d) and a fluid circulation portion (221) as the tubes through which the first fluid flows.
221c) is used, and the pair of flat plates (221b, 221c) and the second perforated flat tube (222) are alternately laminated to form a core portion. The heat exchanger described.