JP2008133994A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems in a cost and storability resulting from use of a gas-liquid separator, in the case where heat exchange performance may be fluctuated sometimes depending on a state of a flow divider, in a conventional heat exchanger. <P>SOLUTION: This heat exchanger 101 is constituted of a fin tube heat exchange part 110 constituted of a gas phase side heat exchange part 102 comprising five paths and a liquid phase side heat exchange part 103 comprising two paths, a gas side flow divider 104 of the second refrigerant flow divider, and a liquid side flow divider 105 of the first refrigerant flow divider. The two paths of liquid phase side heat exchange part 103 is arranged in a lower part in a windward side, the lowermost one path of the gas phase side heat exchange part 102 is arranged in a leeward side thereof. Each of the gas side flow divider 104 and the liquid side flow divider 105 has a gas-liquid separation function, and a gaseous refrigerant is bypassed to a downstream of the heat exchanger 101 from vent pipes 134, 135 via pressure reducers 107, 108. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat exchanger that is mainly used in an air conditioner, a refrigerator, etc., and cools or heats air with a refrigerant, and is capable of adjusting the refrigerant distribution amount to each path. And a technology for providing a sufficient capability of the heat exchanger when cooling the air.

  In an air conditioner that uses a refrigerator and a heat pump cycle for air conditioning, the heat exchanger generally has multiple paths. When the air is cooled by an evaporator, each path is used to extract sufficient performance. Adjust the amount of refrigerant flowing through to balance heat exchange. Conventionally, a flow divider and a thin tube are often used to adjust the refrigerant flow rate (see, for example, Patent Documents 1 and 2).

  For example, a shunt and a thin tube are also used in the technique of Patent Document 1 shown in FIG. In FIG. 4, a conventional air conditioner body 1 is composed of a blowout port 2, a suction port 3, a partition plate 4, an evaporator 5, a blower 6, a flow divider 7, a capillary tube 8, a compressor 10, and the like, and a plenum chamber 9 Is formed at the top.

  In the conventional invention, the capillary tube 8 that communicates the flow divider 7 and each path 5a of the evaporator 5 is configured to guide the flow of the refrigerant according to the wind speed distribution of the heat exchange air guided to the evaporator. The purpose is that each path 5a of the evaporator 5 always obtains uniform heat exchange efficiency. The number of capillaries 8 that communicate the evaporator 5 and the flow divider 7 is two only for the capillaries 8 and 8 that communicate with the path 5a at the inclined upper end of the evaporator 5, and the others are all one. A large amount of refrigerant is circulated and guided from the capillary 8a to the partial path 5a where the wind speed of the heat exchange air sucked from the suction port 3 is the fastest. Therefore, this path 5a is subjected to the heat exchange action in the same state as the other paths 5a, so that the spraying phenomenon does not occur and the heat exchange efficiency is improved.

Further, in Patent Document 2, as shown in FIG. 5, a gas-liquid separator 504 is disposed in front of the refrigerant inflow side divider 501 to avoid the adverse effects of the gas-phase refrigerant, thereby improving the refrigerant branching performance. In FIG. 5, the heat exchanger includes a refrigerant inflow side divider 501, a refrigerant outflow side divider 502, a heat transfer pipe 503, a gas-liquid separator 504, a liquid refrigerant outflow pipe 506, a gas refrigerant outflow pipe 507, an inflow pipe 508, and a refrigerant inflow. A pipe 509, a refrigerant outflow pipe 510, and the like are included.
JP-A-60-251350 Japanese Patent No. 312578

  However, in the conventional technology for improving the heat exchange efficiency of the evaporator using a shunt and a thin tube, the distribution of the refrigerant amount varies depending on the shape of the pipe in front of the shunt and the layout variation such as the slope of the pipe. Therefore, there is a problem that the heat exchange efficiency varies. In addition, the configuration using the gas-liquid separator leads to an increase in the number of parts, and there are problems in terms of cost and storage.

  The present invention suppresses changes in the distribution of the refrigerant amount due to the shape of the piping itself in front of the shunt and the variation in the layout such as the inclination of the piping, etc. The purpose is to provide an exchanger.

  In order to solve the conventional problem, the heat exchanger according to the present invention includes a plurality of gas phase side heat exchange units having a plurality of paths and a large amount of gas phase refrigerant flowing therein, and the number of passes of the gas phase side heat exchange units. A liquid phase side heat exchange section having a plurality of paths having a small amount of liquid phase refrigerant, a first refrigerant flow divider disposed between the liquid phase refrigerant side pipe, the gas phase side heat exchange section, and the It consists of a second refrigerant distributor that relays to the liquid phase side heat exchanging section, and has a relatively low evaporating performance before the lowermost pass of the gas phase side heat exchanging section where the evaporating performance becomes the lowest due to dew, etc. By disposing the low liquid phase side heat exchange section on the windward side, air having high enthalpy is applied to the lowermost path of the gas phase side heat exchange section.

  Thereby, the pass performance of the lowermost part of the gas phase side heat exchange section is improved, and the performance variation of each pass can be suppressed.

  In the heat exchanger of the present invention, at least one of the first flow divider and the second flow divider performs gas-liquid separation to distribute liquid refrigerant to each downstream path, and refrigerant gas is separated separately. To do. Thereby, the state of the refrigerant passing through the flow divider can be stabilized from the gas-liquid two phase to the liquid single phase without increasing the number of components.

  The heat exchanger of the present invention can easily provide a heat exchanger excellent in performance stability by improving the lowermost path performance of the gas phase side heat exchange section and suppressing the performance variation of each path. Can do. In addition, the heat exchanger of the present invention performs gas-liquid separation in the shunt, stabilizes the refrigerant state from the gas-liquid two phase to the liquid single phase, reduces the pressure loss in the heat exchanger, and improves performance and cost. It is possible to provide a heat exchanger that is excellent in storability.

  1st invention WHEREIN: The 1st refrigerant | coolant flow divider arrange | positioned between the said gas phase side heat exchange part, the said liquid phase side heat exchange part through which a lot of liquid phase refrigerants flow, and liquid phase refrigerant side piping, The liquid phase side heat exchanging part having a low evaporation performance is arranged at the lowermost part on the windward side, and is composed of a second refrigerant flow divider that relays the gas phase side heat exchanging part and the liquid phase side heat exchanging part. In addition, by arranging one path of the gas phase side heat exchange section on the leeward side, it is possible to easily provide a heat exchanger excellent in performance stability by suppressing variation in the evaporation capacity of the liquid phase side heat exchange section. can do.

  According to a second aspect of the present invention, in the first aspect, when the heat exchanger is used as an evaporator, the number of passes of the liquid phase side heat exchanging portion is the suction portion when the liquid phase side heat exchanging portion is an evaporation portion. By setting the temperature to be between the air temperature and the refrigerant temperature of the gas phase side heat exchanging section, it is possible to provide a heat exchanger that is more excellent in evaporation capability and easy to adjust the diversion.

  According to a third aspect of the present invention, in the first aspect, at least one of the first flow divider and the second flow divider performs gas-liquid separation to distribute liquid refrigerant to each downstream path, and the refrigerant gas is Separately separates the state of the refrigerant from the gas-liquid two phase to the liquid single phase, facilitates the diversion adjustment, reduces the pressure loss of the heat exchanger, and excels in performance, cost and storage Can be provided.

  According to a fourth invention, in the third invention, it is possible to provide a flow divider that performs gas-liquid separation with a simple structure and is inexpensive, and to provide a heat exchanger that is excellent in cost.

  According to a fifth invention, in the third invention, a flow divider excellent in gas-liquid separation performance can be provided, and a heat exchanger excellent in performance can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a heat exchanger according to Embodiment 1 of the present invention. And the refrigerant | coolant and air flow when functioning as an evaporator are shown by the arrow in a figure.

  The heat exchanger 101 is a finned tube heat composed of a gas phase side heat exchanging portion 102 composed of five paths 102a, 102b, 102c, 102d, and 102e and a liquid phase side heat exchanging portion 103 composed of two paths 103a and 103b. An exchange unit 110, a gas-side flow divider 104 that is a second refrigerant flow divider disposed between the gas-phase side heat exchange unit 102 and the liquid-phase side heat exchange unit 103, and the liquid-phase side heat exchange unit 103. And a liquid-side flow divider 105 which is a first refrigerant flow divider disposed between the liquid-phase refrigerant pipe 115 and the liquid-phase refrigerant pipe 115.

  The heat exchange air flows in the direction of the arrow 109, and the two paths 103a and 103b of the liquid phase side heat exchange unit 103 are arranged in the lower part on the windward side. The paths 102 a, 102 b, 102 c, 102 d, 102 e of the gas phase side heat exchange unit 102 are arranged in order from the top of the heat exchanger 101, but the path 102 e is arranged on the leeward side of the liquid phase side heat exchange unit 103. ing. Both the gas-side flow divider 104 and the liquid-side flow divider 105 have a gas-liquid separation function, and the gas refrigerant is supplied to the heat exchanger 101 from the gas vent pipes 134 and 135 via the decompressors 107 and 108, respectively. Bypass downstream.

  Next, the function of the heat exchanger 101 as an evaporator will be described along the order in which the refrigerant flows. First, a gas-liquid two-phase refrigerant having a small dryness flows from the liquid-phase side refrigerant pipe 115 to the liquid-side flow divider 105. In the liquid-side flow divider 105, the refrigerant is separated into gas and liquid, the gas refrigerant passes through the depressurizer 108 from the degassing pipe 135, and merges with the outlet 116 of the heat exchanger 101, and the liquid refrigerant flows in the diversion pipes 125a and 125b. And is sent to the paths 103a and 103b of the liquid phase side heat exchange section. The liquid refrigerant passes through the paths 103a and 103b while evaporating, merges in the gas-liquid refrigerant pipe 114, and flows into the gas-side flow divider 104.

  In the gas side diverter 104, the refrigerant is separated into a gas and a liquid, the gas refrigerant passes through the decompression pipe 107 from the degassing pipe 134 and merges with the outlet 116 of the heat exchanger 101, and the liquid refrigerant is divided into the diversion pipes 124a and 124b. , 124c, 124d, and 124e, and are sent to the paths 102a, 102b, 102c, 102d, and 102e of the gas phase side heat exchange unit 102.

  Usually, when using the fin tube heat exchange unit 110 as an evaporator, dew drops from the top to the bottom, especially under conditions where dew is easily attached, so there is a lot of dew on the fins at the bottom of the heat exchanger, Ventilation resistance rises and the heat exchange performance of the lower path is greatly reduced.

  However, in the above configuration, the liquid phase side heat exchanging section 102, that is, the lower part of the windward, has a high evaporation temperature and a small amount of heat absorption because the number of passes of the gas phase side heat exchanging section 102 is small. Accordingly, a decrease in the amount of air passing through this portion can be suppressed, and the enthalpy of air passing through the paths 103a and 103b is higher than the enthalpy of air passing through one row of other portions. Evaporation capacity is reduced by placing the bottom path, which normally has the smallest evaporation capacity, as a path 102e with a large opening in one row and heat exchange with high enthalpy air. Can be suppressed. As a result, the diversion adjustment in the gas side diverter 104 can be easily performed.

The smaller the number of passes of the liquid-phase side heat exchanging unit 103, the better the heat exchange performance as a condenser, but the heat exchange performance as an evaporator decreases. The smaller the number of passes of the liquid-phase side heat exchanging unit 103 in the evaporator, the higher the temperature of the refrigerant flowing through that portion. In some cases, the evaporator may be in a heat dissipation state instead of an endothermic state. Naturally, when it becomes a heat dissipation state, it can not be said that the heat exchange performance is good as an evaporator, and the temperature of the air that has passed through the liquid phase side heat exchange unit 103 becomes higher than the outside air temperature, In some cases, the heat exchange performance downstream of the air of the liquid phase side heat exchanging unit 103 is excessively increased, and the diversion adjustment becomes difficult.

  Therefore, there is an appropriate value for the number of passes of the liquid-phase side heat exchange unit 103, and the appropriate value varies depending on the specifications of the heat exchanger. As a suitable number of passes, when operating as an evaporator with a predetermined capacity, the temperature of the refrigerant flowing through the liquid phase side heat exchange unit 103 is equal to or slightly lower than the heat exchange air, and the refrigerant of the gas phase side heat exchange unit 102 It is better to set the temperature higher than the temperature.

  As described above, in the first embodiment, both the gas-side flow divider 104 and the liquid-side flow divider 105 have a gas-liquid separation function, and the gas refrigerant is bypassed downstream of the heat exchanger 101. To do. Thereby, the pressure loss of the heat exchanger 101 is lowered and the heat exchange capability of the heat exchanger 101 is improved. In addition, since the state of the refrigerant at the time of the diversion becomes a liquid, the flow is stabilized and the diversion adjustment becomes very easy.

  The structures of the gas-side flow divider 104 and the liquid-side flow divider 105 may be basically the same as the number of passes after diversion in the evaporator is different. Specifically, the structure as shown in FIG. 2 or 3 is desirable.

  FIG. 2 shows an example of the gas-side flow divider in the first embodiment of the present invention. The refrigerant that has flowed into the gas-side flow divider 204 from the gas-liquid refrigerant pipe 114 is caused to flow along the side wall 251 as indicated by an arrow 252. In the meantime, it is separated into gas and liquid by gravity, and the gas refrigerant flows into the gas vent pipe 134 as shown by the arrow 254, and the liquid refrigerant falls along the side wall as shown by the arrow 253, and is divided into the shunt pipes 124a, 124b, etc. Then, it is sent to the path of the gas phase side heat exchange unit 102. As can be seen from FIG. 2, the gas-side flow divider 204 has a very simple configuration and can be manufactured at low cost. Further, this shunt is effective when used as a liquid side shunt with the same structure.

  FIG. 3 is an example of the gas-side flow divider in the first embodiment of the present invention. The refrigerant that has flowed into the gas-side flow divider 304 from the gas-liquid refrigerant pipe 114 is a liquid refrigerant that is directly under the refrigerant inlet as indicated by an arrow 352. It flows along or away from the shield plate 355 and is separated into a gas and a liquid in the meantime, the gas refrigerant flows into the gas vent pipe 134 as indicated by an arrow 354, and the liquid refrigerant is discharged from the liquid refrigerant remover plate 355 as indicated by an arrow 353. It is dropped or dropped through the side wall 351, and is diverted to the diversion pipes 124a and 124b and sent to the path of the gas phase side heat exchange section. Since the gas side flow divider 304 in FIG. 3 prevents the liquid refrigerant from flowing into the gas vent pipe 134 by the liquid refrigerant release plate 355, high gas-liquid separation performance can be obtained. Further, this shunt is effective when used as a liquid side shunt with the same structure.

  The heat exchanger of the present invention improves and stabilizes the heat exchange performance of the evaporator, and is particularly effective as a heat exchanger for an air conditioner, etc., such as a refrigerator, a heat pump water heater or a dehumidifier It can also be applied to other devices. Moreover, it has an effect irrespective of the kind of refrigerant.

The block diagram of the heat exchanger in Embodiment 1 of this invention Sectional drawing of the refrigerant | coolant shunt in Embodiment 1 of this invention Sectional drawing of the refrigerant | coolant shunt in Embodiment 1 of this invention (A) Explanatory drawing of the heat exchanger of the prior art described in patent document 1, (b) The principal part enlarged view of Fig.4 (a). Explanatory drawing of the heat exchanger of the prior art described in patent document 2

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Heat exchanger 102 Gas phase side heat exchange part 102a, 102b, 102c, 102d, 102e Gas phase side heat exchange part path 103 Liquid phase side heat exchange part 103a, 103b Liquid phase side heat exchange part path 104 Gas side shunt 105 Liquid side shunt 107, 108 Pressure reducer 110 Fin tube heat exchange section 114 Gas-liquid refrigerant pipe 115 Liquid phase side refrigerant pipe 124a, 124b, 124c, 124d, 124e Branch pipe 125a, 125b Branch pipe 134, 135 Gas vent pipe 355 Liquid Refrigerant shield

Claims (5)

A gas-phase-side heat exchange section that has a plurality of paths and a large amount of gas-phase refrigerant flows therein, and a liquid that has a plurality of paths smaller than the number of paths in the gas-phase-side heat exchange section and that flows a large amount of liquid-phase refrigerant A phase-side heat exchange unit, a first refrigerant flow distributor disposed between the liquid-phase side heat exchange unit and the liquid-phase refrigerant side pipe, the gas-phase side heat exchange unit, and the liquid-phase side heat exchange unit A liquid refrigerant side heat exchanging unit is arranged at the lowermost part on the uppermost wind side, and the leeward side of the liquid phase side heat exchanging part is the gas phase side heat. A heat exchanger characterized in that one path of the exchanger is occupied. When the heat exchanger is used as an evaporator, the number of passes of the liquid phase side heat exchanging unit is such that the liquid phase side heat exchanging unit becomes an evaporating unit, and the suction air temperature and the gas phase side heat exchanging unit The heat exchanger according to claim 1, wherein the heat exchanger is set to a temperature between the refrigerant temperature. The at least one of the first shunt and the second shunt performs gas-liquid separation, distributes liquid refrigerant to each downstream path, and separates refrigerant gas separately. The described heat exchanger. When the first diverter and the second diverter use a heat exchanger as an evaporator, a cylindrical structure in which a gas vent pipe is arranged on the ceiling and a plurality of liquid vent pipes are arranged on the bottom part. The heat exchanger according to claim 3, wherein the heat exchanger is configured to flow in a gas-liquid two-phase refrigerant along a cylindrical surface and perform gas-liquid separation by gravity. When the first diverter and the second diverter use a heat exchanger as an evaporator, a gas / liquid two-phase refrigerant inlet is provided from the ceiling, and a plurality of liquid drain pipes are provided on the bottom. 4. The heat exchanger according to claim 3, wherein the heat exchanger has a cylindrical structure, and a liquid refrigerant shield plate and a gas vent pipe are arranged immediately below the gas-liquid two-phase refrigerant inlet.