JP2009041876A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger evenly distributing a heat exchange medium by a plurality of tubes. <P>SOLUTION: The heat exchanger has a plurality of tubes 4, an inlet header 1 to distribute a heat exchange medium R to the plurality of tubes 4; and an outlet header to recover the heat exchange medium R from the plurality of tubes 4. The inlet header 1 contains: a forward passage 31 extending from bottom to top; a backward passage 32 extending from top to bottom; an upper communicating passage 33 connecting the upper end 31a of the forward passage 31 with the upper end 32a of the backward passage 32; and a lower communicating passage 34 connecting the lower end 31b of the forward passage 31 and the lower end 32b of the backward passage 32. The plurality of tubes 4a is connected to the backward passage 32. The upper inner wall 4s of the uppermost tube 4a among the plurality of tubes 4 is located below the lower end 33a of the upper communicating passage 33. The inlet header 1 also contains a discharge mechanism 11 receiving heat exchange medium R through the inlet header 1 from the lower part 31b of the forward passage 31 and sending it to the upper part of the forward passage 31. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a heat exchanger used in a refrigeration or cooling device.

  In the heat exchanger, in order to increase the heat exchange efficiency, it is important to evenly distribute the heat exchange medium (refrigerant) supplied to the header to a plurality of tubes for heat exchange. In a heat exchanger, the inflowing heat exchange medium is often in a two-phase state including a gas phase and a liquid phase. In this case, in the header, a liquid component having a large specific gravity and easily affected by gravity is separated from a gas component having a small specific gravity and hardly affected by gravity, or the mixing ratio of these components greatly changes. Accordingly, the refrigerant distribution to the plurality of tubes for heat exchange is likely to be uneven (non-uniform). Such non-uniform distribution of the heat exchange medium is significant when the heat exchanger is used in such a posture that the header is in the vertical direction. For this reason, there is a need for a heat exchanger that can more uniformly distribute the heat exchange medium to the tubes.

  In order to improve the uneven distribution of the heat exchange medium, the heat exchanger is a distributor formed by bending a plurality of distribution pipes three-dimensionally into different shapes as introduced in the prior art of Patent Document 1. What you have is known. Patent Document 1 discloses a heat exchanger in which a plurality of distribution pipes are concentrated on a part of an inlet header in which liquid refrigerant is accumulated.

Furthermore, Patent Document 2 includes an evaporator including an inlet header, an outlet header, a plurality of tubes extending between both headers, and meandering fins interposed between adjacent tubes. It is disclosed. In this evaporator, a plurality of refrigerant injectors are provided at the inlet to the inlet header. Each of the plurality of refrigerant injectors has an injection orifice.
JP 2004-317056 A JP 2000-249428 A

  In a heat exchanger provided with a distributor, it is necessary to bend a plurality of distribution pipes into shapes that are different in shape and complicated in three dimensions. For this reason, there are many parts and the manufacturing cost tends to become high. Furthermore, since a space is required to arrange the distribution pipe having a three-dimensionally bent shape, the header and the heat exchanger are easily increased in size.

  Furthermore, the heat exchanger described in Patent Document 1 is provided with refrigerant distribution means using flat distribution pipes, and concentrates the flat distribution pipes in a part of the header, particularly in the lower part of the header where liquid refrigerant easily collects. Thus, the liquid refrigerant is caused to flow into the heat exchange section. In such a structure, the refrigerant state at the inlets of the plurality of flat distribution pipes approaches uniformly, but the difference in tube pressure loss due to the difference in tube length occurs, so the refrigerant distribution to the plurality of tubes is not necessarily uniform. I can't say. Furthermore, since it becomes the structure which arrange | positions the some flat distribution pipe | tube with a bending part, it is difficult to provide the heat exchanger of a simple structure.

  Like the evaporator described in Patent Document 2, even if an injection orifice is provided at the inlet to the header, it is difficult to inject the refrigerant so that the refrigerant is uniformly distributed throughout the header. Distribution is sensitive to flow rate. Typically, even if the effect of arranging the header in the horizontal direction is recognized, it is not possible to fundamentally solve the fact that the refrigerant distribution tends to change inside the header when the header is arranged vertically or vertically. Absent.

  One aspect of the present invention is a heat exchanger having a plurality of tubes, an inlet header for distributing the heat exchange medium to the plurality of tubes, and an outlet header for recovering the heat exchange medium from the plurality of tubes. is there. In this heat exchanger, the inlet header includes an outward path extending from the lower side to the upper side, a return path extending from the upper side to the lower side, an upper communication path connecting the upper part of the forward path and the upper part of the return path, a lower part of the forward path, and a lower part of the return path. The plurality of tubes are connected to the return path. The upper inner surface of the uppermost tube among the plurality of tubes is located below the lower end portion of the upper communication path. The inlet header further includes a discharge mechanism for blowing the heat exchange medium flowing into the inlet header upward from the lower part of the outward path.

  According to this heat exchanger, the heat exchange medium is blown out to the upper side of the forward path by the discharge mechanism, and is distributed to a plurality of tubes connected to the return path while flowing through the upper communication path and the return path. The heat exchange medium that has not been distributed to the plurality of tubes passes through the lower communication path and returns to the forward path. According to this heat exchanger, the heat exchange medium circulates inside the inlet header, and is distributed to the plurality of tubes connected to the return path in the return path.

  According to this heat exchanger, the heat exchange medium flowing into the inlet header is forcibly circulated inside the inlet header by the forward path, the backward path, and the discharge mechanism. For this reason, the state of the heat exchange medium inside the inlet header can be made more uniform or nearly uniform.

  Further, according to this heat exchanger, the heat exchange medium is circulated by the discharge mechanism, and the heat exchange medium flowing into the inlet header is blown upward from the lower part of the forward path extending up and down, and the tube in the return path extending up and down. Thus, the heat exchange medium is more evenly distributed to the plurality of tubes by utilizing gravity. Therefore, the heat exchanger of the present invention is typically suitable for a heat exchanger in which headers are arranged vertically or vertically.

  That is, in the heat exchanger in which the heat exchange medium is supplied to the return path extending from the upper side to the lower side via the outward path extending from the lower side to the upper side, the discharge mechanism blows the upper path to the upper path, passes through the upper communication path, The heat exchange medium that has reached the return path, typically a liquid-phase heat exchange medium, reaches the lower part of the return path while falling due to its own weight (gravity). Therefore, the state in the return path is stable, and the heat exchange medium is distributed almost evenly to the plurality of tubes connected to the return path.

  Further, the liquid-phase heat exchange medium phase-separated inside the header may accumulate downward due to gravity. By connecting the forward path and the return path with a lower communication path and blowing the heat exchange medium from the lower side to the upper side in the forward path extending from the lower side to the upper side, the liquid phase heat exchange medium accumulated below is blown up and recirculated. Can do. Therefore, even if the liquid phase heat exchange medium accumulates in the lower communication path connected to the lower side of the return path, the heat exchange medium is distributed almost evenly to the plurality of tubes connected to the return path.

  On the upper side (upper communication path) above the lower end of the upper communication path, the dynamic pressure (kinetic energy) of the heat exchange medium when going from the forward path to the return path distributes the heat exchange medium evenly to multiple tubes. It can be an obstacle. Therefore, the condition that the heat exchange medium flows into the plurality of tubes connected to the return path by setting the upper inner surface of the uppermost tube of the plurality of tubes below the lower end portion of the upper communication path. Becomes more constant, and the heat exchange medium that has reached the return path can be more evenly distributed to the plurality of tubes.

  In this heat exchanger, it is preferable that the lower inner surface of the lowermost tube among the plurality of tubes is located above the upper end portion of the lower communication path. Even if a part of the heat exchange medium accumulates in the lower communication path (below the upper end portion of the lower communication path), the region of the lowermost tube (the heat exchange medium may accumulate) The area where the heat exchange medium flows into the plurality of tubes connected to the return path becomes more constant, and the heat exchange medium that has reached the return path is more evenly distributed to the plurality of tubes. Can be distributed.

  In this heat exchanger, the discharge end of the discharge mechanism may be located below the upper end portion of the lower communication path, and the discharge end of the discharge mechanism is higher than the upper end portion of the lower communication path. May be located. By disposing the discharge end of the discharge mechanism above the upper end of the lower communication path, the heat exchange medium can be introduced into the inlet header from the direction intersecting the forward path. In this case, it is preferable that the inlet header further includes an inlet for allowing the heat exchange medium to flow into the inlet header from a direction intersecting the outward path.

  In this heat exchanger, an example of the discharge mechanism includes an orifice. In addition, another example of the discharge mechanism includes an ejector (an ejector having an ejector nozzle) that mixes and blows out at least a part of the heat exchange medium that has already flowed into the inlet header.

  At least a part of the inlet header can be constituted by a double pipe or a perforated pipe (multiple pipe, multi-flow pipe). That is, one aspect of the inlet header includes an outward path extending from the lower side to the upper side, a return path extending from the upper side to the lower side, and a partition wall separating the forward path and the return path. In this case, the upper end of the partition corresponds to the lower end of the upper communication path, and the lower end of the partition corresponds to the upper end of the lower communication path.

  Accordingly, another aspect of the present invention provides a heat exchange having a plurality of tubes, an inlet header for distributing the heat exchange medium to the plurality of tubes, and an outlet header for recovering the heat exchange medium from the plurality of tubes. In this heat exchanger, the inlet header includes an outward path extending from the lower side to the upper side, a return path extending from the upper side to the lower side, and a partition wall separating the forward path and the return path. The plurality of tubes are connected to the return path. The upper inner surface of the uppermost tube among the plurality of tubes is positioned below the upper end of the partition wall. The inlet header further includes a discharge mechanism for blowing the heat exchange medium flowing into the inlet header upward from the lower part of the outward path.

  In this heat exchanger, it is preferable that the lower inner surface of the lowermost tube among the plurality of tubes is positioned above the lower end of the partition wall.

  Yet another embodiment of the present invention is a system (heat exchange system) having the above-described heat exchanger and an apparatus (medium supply system) for supplying a heat exchange medium to the heat exchanger. Such systems (heat exchange systems) include refrigeration cycles or refrigeration cycles, and refrigeration equipment, refrigeration equipment, air conditioning equipment, storage, showcases, etc. including such cycles. A system suitable as a cooling cycle or a refrigeration cycle includes an evaporator that cools an external fluid by heat exchange with a heat exchange medium, a pressure device that pressurizes the heat exchange medium recovered from the evaporator, and a pressure device. And a condenser for cooling the compressed heat exchange medium.

  Accordingly, still another aspect of the present invention provides an evaporator that cools the external fluid by heat exchange with the heat exchange medium, a pressurizer that pressurizes the heat exchange medium recovered from the evaporator, and a pressurizer. And a condenser for cooling the compressed heat exchange medium. In this system, the evaporator and / or condenser is the heat exchanger described above.

  FIG. 1 shows a system 50 that includes a heat exchanger. An example of this system (heat exchange system) 50 is an air conditioner or a refrigeration apparatus. The system 50 may be another system having a heat exchange cycle called a cooling cycle or a refrigeration cycle. FIG. 1 schematically illustrates the system 50, and the number of tubes 4 of the evaporator 100 (heat exchanger 300a) is an example.

  If the system (heat exchange system) 50 is an air conditioning system, the system 50 includes a liquid heat exchange medium (hereinafter referred to as a refrigerant) R and an external fluid (for example, outdoor air) F. Heat exchange between them. The system 50 includes an evaporator 100 that cools an external fluid (for example, indoor air) G by heat exchange with the refrigerant R, a compressed gaseous (gas phase) refrigerant R, and an external fluid F. And a condenser (condenser) 200 for changing the refrigerant R into a liquid (liquid phase).

  Further, the system 50 includes an apparatus (medium supply system) 55 that circulates the refrigerant R and supplies the refrigerant R to the evaporator 100 that is the heat exchanger 300a. The medium supply system 55 that supplies the refrigerant R to the evaporator 100 includes a capacitor 200. This system 50 includes, as a medium supply system 55, a compressor 51 that pressurizes the refrigerant R, an accumulator 52 that temporarily stores the refrigerant R, an expansion valve 53 that expands the refrigerant R supplied to the evaporator 100, in addition to the condenser 200. have. In this system 50, the refrigerant R that has flowed into the evaporator 100 flows out from the outlet (refrigerant outlet) 6 of the evaporator 100, passes through the accumulator 52, the compressor 51, the condenser 200, and the expansion valve 53, and flows into the inlet of the evaporator 100. From the (refrigerant inlet) 5, the refrigerant is circulated so as to flow into the evaporator 100 again.

  A typical evaporator 100 includes an inlet header 1 including an inlet (refrigerant inlet) 5, an outlet header 2 including an outlet (refrigerant outlet) 6, and a heat exchange unit 9. The inlet header 1 and the outlet header 2 extend in the vertical direction, and are arranged so as to be parallel to each other. The heat exchanging section 9 is for exchanging heat between the refrigerant R and the air G and cooling the air G and the like. The heat exchange unit 9 includes a plurality of tubes 4 arranged in parallel to each other in the horizontal direction so as to allow the inlet header 1 and the outlet header 2 to communicate with each other, and a plurality of fins extending in the vertical direction so as to be orthogonal to the tubes 4. 3 is provided. The evaporator 100 may have a plurality of tubes 4 arranged in a U-shape or S-shape, and is not limited to that shown in FIG.

  In FIG. 2, the outline of the part of the inlet header 1 and the tube 4 of the heat exchanger 300a concerning the 1st Embodiment of this invention is shown by the cross section of the vertical direction. FIG. 3 shows a cross-sectional view taken along line III-III in FIG. FIG. 4 shows an expanded structure of the inlet header of the heat exchanger 300a of FIG. This heat exchanger 300a can be used as the evaporator 100 of the system 50, and will be described below using an example of the case where it is used as an evaporator. The heat exchanger 300a may be used as the condenser 200 of the system 50.

  As shown in FIGS. 2 and 4, in this example, as the tube 4, 18 flat tubes having a flat cross section are used. The number of tubes 4 is arbitrary. The tube 4 may have a circular cross section. Moreover, the tube 4 may be a porous tube (multiple tube) whose inside is divided into a plurality. A typical fin 3 is a plurality of plate-like fins that are arranged in parallel to each other and attached so that the tube 4 passes therethrough. The fins 3 may be corrugated fins that connect between the tubes 4 while meandering, fin-like or pin-like fins protruding from the tubes 4, and the like.

  The inlet header 1 has a function as a distributor for distributing (dividing) the refrigerant R to the plurality of tubes 4 of the heat exchange unit 9. The outlet header 2 has a function of collecting the refrigerant R from each tube 4. Each tube 4 has one end connected to the inlet header 1 and the other end connected to the outlet header 2. By adopting flat tubes as the plurality of tubes 4, the heat exchange area by the tubes themselves can be increased. Moreover, by providing the fins 3, the heat exchange area (contact area) with the air G or the like can be further increased, and the heat exchange efficiency can be improved. In order to avoid the effects of icing and frosting, the fins 3 can be omitted or the area occupied by the fins 3 can be reduced.

  The inlet header 1 includes a circulation path (circulation pipe) 10 that can circulate at least a part of the refrigerant R flowing into the inlet header 1. The circulation path 10 includes an outward path 31 extending from the lower side to the upper side and a return path 32 extending from the upper side to the lower side. The upper part 31a of the forward path 31 and the upper part 32a of the return path 32 are connected by the upper communication path 33. The lower part 31 b of 31 and the lower part 32 b of the return path 32 are connected by a lower communication path 34.

  Specifically, the inlet header 1 is composed of a double pipe 43 having an inner pipe 41 and an outer pipe 42. The outer tube 42 is constituted by two members 44a and 44b formed by extrusion and cutting and having a semicircular cross section. A member 44c having a semicircular cross section is attached to the outer member 44a to constitute the inner tube 41. Between the outer member (member to which the tube 4 is not connected) 44a and the inner member 44c (inside the inner tube 41) is the forward path 31, the inner member 44c and the inner member (member to which the tube 4 is connected) 44b. The return path 32 is between the two. The internal member 44 c functions as a partition wall 35 that separates the forward path 31 and the return path 32. In this example, the inlet header 1 is formed so that the cross-sectional area of the forward path 31, the cross-sectional area of the return path 32, the cross-sectional area of the upper communication path 33, and the cross-sectional area of the lower communication path 34 are substantially equal.

  A plurality of flat tubes 4 are connected to the inner member 44b constituting the return path 32 at substantially equal intervals. These flat tubes 4 are connected to the outlet header 2. An upper cap 45 and a lower cap 46 are provided on the upper and lower portions of the double tube 43 (both ends of the two members 44a and 44b constituting the outer tube 42). The upper cap 45 and the lower cap 46 and the upper and lower ends of the inner member 44c serving as a partition wall are an upper communication passage 33 and a lower communication passage 34, respectively, which connect the inner tube 41 and the outer tube 42. That is, the inner pipe 41 that is the forward path 31 and the outer pipe 42 that is the return path 32 communicate with each other in the upper communication path 33 and the lower lower communication path 34 in the upper part of the inlet header 1.

  The inlet header 1 further includes a discharge mechanism 11 for blowing out the refrigerant R flowing into the inlet header 1 from the lower portion 31b of the forward path 31 to the forward path 31. The discharge mechanism 11 of this example includes an orifice (nozzle, throttle part) 12. The end of the path connected to the lower communication path 34 is visible in the vicinity of the orifice 12, and by blowing out the refrigerant R flowing into the inlet header 1 from the orifice 12, at least the refrigerant R already flowing into the inlet header 1 is seen. A part of the refrigerant R is sucked, and the refrigerant R flowing into the inlet header 1 and at least a part of the refrigerant R already flowing into the inlet header 1 are mixed and blown upward to the forward path 31.

  Specifically, at the lower end of the inner pipe 41, that is, at the lower part of the forward path 31, a discharge nozzle (discharge nozzle member, discharge from the return path 32 by discharging the refrigerant R) including the inlet 5 of the refrigerant R and the discharge mechanism 11. A nozzle member 13 for sucking the refrigerant R is provided. The discharge nozzle member 13 is formed by forging, for example. The discharge nozzle member 13 extends in a direction intersecting, for example, orthogonal to the forward path 31, and a pipe connection portion 13a for connecting the inflow pipe 59 (see FIG. 1) of the refrigerant R, and the front of the pipe connection portion 13a. And a discharge portion 13b. The discharge part 13b is provided so as to extend upward from the lower front part of the pipe connection part 13a. The upper portion of the discharge portion 13 b is an orifice 12, and the upper surface of the orifice 12 is a discharge end 15.

  The pipe connection portion 13 a of the discharge nozzle member 13 serves as an inlet 5 for allowing the refrigerant R to flow into the inlet header 1 from a direction intersecting, for example, orthogonal to the forward path 31. Further, the gap 14 between the outer surface of the discharge portion 13b and the inner pipe 41 (inner member 44c) is connected to the lower communication path 34, and at least a part of the refrigerant R already flowing into the inlet header 1, that is, the return path In order to suck at least a part of the refrigerant R flowing through 32 and mix this refrigerant R (at least a part of the refrigerant R already flowing into the inlet header 1) with the refrigerant R flowing into the inlet header 1. It becomes the suction part.

  The discharge nozzle member 13 includes a discharge mechanism 11 that generates a differential pressure by an orifice and blows out the refrigerant R flowing into the header 1 to the inside of the forward path 31. That is, the discharge mechanism 11 functions as a differential pressure generating mechanism 13. Further, due to the suction force of the refrigerant R blown upward from the lower part 31b of the forward path 31, the existing (inflowed) refrigerant R from the return path 32 is sucked into the forward path 31 via the suction unit 14, Together with the refrigerant R flowing into the header 1, it blows out upward in the forward path 31.

  When connecting a pipe for injecting refrigerant to the lower side of the inlet header of the heat exchanger, a space for arranging the refrigerant pipe is required below the inlet header, and the lower side of the other part of the heat exchanger becomes a dead space. Cheap. In this heat exchanger 300a, since the refrigerant R flows into the inlet header 1 from the side, the refrigerant piping can be arranged to the side of the inlet header 1. For this reason, the lower side of the heat exchanger including the lower side of the inlet header 1 is unlikely to become a dead space. For this reason, the system 50 can be arranged compactly by using this heat exchanger 300a.

  FIG. 5 is an enlarged view of the area surrounded by the circle V in FIG. FIG. 6 shows an enlarged view of a region surrounded by a circle VI in FIG.

  In the heat exchanger 300a, the upper inner surface 4s of the uppermost tube 4a among the plurality of tubes 4 connected to the header 1 is lower than the lower end portion 33a of the upper communication passage 33 (the upper end portion 35a of the partition wall 35). , It is positioned (shifted) downward by the distance d1. In the heat exchanger 300a, the lower inner surface 4t of the lowermost tube 4b among the plurality of tubes 4 is more distant than the upper end portion 34a of the lower communication passage 34 (lower end portion 35b of the partition wall 35). It is positioned (shifted) upward by d2. Further, the discharge end 15 of the discharge mechanism 11, that is, the discharge end of the orifice 12 is located above the upper end portion 34 a of the lower communication path 34 by a distance d3. In this example, the discharge end 15 of the orifice 12 is positioned above the lower inner surface 4t of the tube 4b at the lowest side among the plurality of tubes 4 (d2 <d3).

  The heat exchanger 300a functions (acts) as follows. In the heat exchanger 300a applied as an evaporator of the heat exchange system 50, the refrigerant R in a two-phase state in which a liquid phase or a mixture of gas and liquid is mixed by the action of the compressor 51, the expansion valve 53, etc. Flows into the inlet header 1 (supplied). In the inlet header 1, the refrigerant R that flows in is blown upward from the lower portion 31 b of the forward path 31 by the orifice 12 of the discharge mechanism 11. As the refrigerant R flows into the inlet header 1 via the orifice 12, a differential pressure is generated before and after the orifice 12, and the flowing refrigerant R is blown out to the forward path 31. Moreover, since the inside of the outward path 31 is decompressed by the orifice 12, the blown-out refrigerant R becomes a two-phase flow including a liquid phase and a gas phase.

  The refrigerant R blown upward to the forward path 31 by the discharge mechanism 11 passes through the forward path 31 and the upper communication path 33 and is distributed to a plurality of tubes 4 connected to the return path 32. Further, the refrigerant R that has not been distributed to the plurality of tubes 4 is sucked into the forward path 31 via the lower communication path 34 and the suction portion 14 by the suction force generated by the refrigerant R blown upward in the forward path 31. And mixed with the blown out refrigerant R. For this reason, together with the refrigerant R flowing into the header 1, it is blown out upward in the forward path 31.

  According to this heat exchanger 300a, the circulation path 10 including the forward path 31 and the return path 32 and the discharge mechanism 11 are provided, and the refrigerant R flowing into the inlet header 1 is blown upward from the lower part of the forward path 31 extending vertically. By distributing to the plurality of tubes 4 in the return path 32 extending vertically, conventionally, the refrigerant R is distributed to the plurality of tubes 4 by reversely using the gravity that causes the gas phase and the liquid phase to be separated. On the other hand, it is distributed more uniformly.

  First, assuming that the refrigerant R is distributed in the forward path extending from the lower side to the upper side, the discharge mechanism is sufficient to cause the refrigerant R, particularly the liquid refrigerant R, to reach the end (upper part) of the forward path against gravity. It is necessary to blow out the refrigerant R at a speed. Accordingly, in the forward path, the dynamic pressure (kinetic energy, pressure fluctuation) due to the refrigerant R being blown out at high speed, gravity, and if the outlet header is negative pressure, the suction force works through the tube, and the state of the forward path Is complicated, and the internal pressure of the outward path is likely to fluctuate greatly.

  On the other hand, in this example, the return path 32 that connects the upper part 31 a and the lower part 31 b of the forward path 31 is provided to constitute the circulation path 10, and the refrigerant R is distributed in the return path 32. In this case, the refrigerant R that has reached the upper part 31 a of the forward path 31 flows into the return path 32. Accordingly, the refrigerant R does not stagnate in the upper part of the forward path, and the refrigerant R does not flow backward due to gravity in the forward path as in the case of distribution in the forward path.

  Further, in the return path 32 extending from the upper part 32a to the lower part 32b, the refrigerant R, typically the liquid-phase refrigerant R that has reached the return path 32 through the upper communication path 33 is dropped due to its own weight (gravity). The end (lower part) 32b of 32 is reached. For this reason, there is little influence of the dynamic pressure resulting from the refrigerant | coolant R blowing out at high speed. Therefore, the state in which the refrigerant R is distributed in the return path 32 is stable as compared with the state in which the refrigerant R is distributed in the forward path, and the refrigerant R is evenly distributed to the plurality of tubes 4 connected to the return path 32. It becomes easy.

  Further, the liquid-phase refrigerant R separated from the gas phase inside the header 1 may accumulate downward due to its own weight (gravity) in the return path 32 extending vertically. The forward path 31 and the return path 32 are connected by the lower communication path 34, and the refrigerant R is blown upward from the lower side 31 b in the forward path 31 extending from the bottom to the top, so that the lower path 32 b (lower communication path 34) accumulates. The liquid phase refrigerant R can be blown up and recirculated. Therefore, since it is possible to suppress the liquid-phase refrigerant R from being accumulated on the lower side 32b in the return path 32, it can be said that the refrigerant R is easily distributed almost evenly to the plurality of tubes 4 connected to the return path 32.

  Thus, according to this heat exchanger 300a, since at least a part of the refrigerant R is forcibly circulated through the inlet header 1, the axial length is long and the length (vertical direction or vertical direction) extends. Even in the pipe-like inlet header 1, it is possible to prevent the occurrence of a state in which the liquid phase and the gas phase are separated due to a head difference (gravity) in a static state.

  In this circulation system, in the upper communication path 33 (above the lower end portion 33a of the upper communication path 33) of the return path 32, from the forward path 31 side in the direction of the upper communication path 33 rather than the lower end portion 33a of the upper communication path 33. Dynamic pressure (kinetic energy) works on the return path 32 side. For this reason, when the upper inner surface 4s of the uppermost tube 4a among the plurality of tubes 4 is positioned above the lower end portion 33a of the upper communication path 33, the tube at such a position is more A lot of refrigerant R flows.

  In this heat exchanger 300a, the uppermost inner surface 4s of the tube 4a on the uppermost side of the plurality of tubes 4 is located below the lower end portion 33a of the upper communication passage 33 (the upper end portion 35a of the partition wall 35). As shown in FIG. For this reason, all the tubes 4 including the uppermost tube 4a are hardly affected by dynamic pressure (kinetic energy), and the refrigerant R is distributed almost evenly to all the tubes 4 including the tubes 4a.

  In the heat exchanger 300 a, the discharge end 15 of the discharge mechanism 11 is located above the upper end portion 34 a of the lower communication path 34, and the refrigerant R may accumulate in the lower communication path 34. However, when the liquid refrigerant R is accumulated up to the upper end portion 34a of the lower communication passage 34 (the lower end portion 35b of the partition wall 35), the lower communication passage 34 is sealed with the liquid refrigerant R, so that the liquid refrigerant R Is forcibly sucked into the forward path 31 and the liquid level decreases. Therefore, in this heat exchanger 300a, the upper end portion 34a of the lower communication passage 34 (the lower end portion 35b of the partition wall 35) is the upper limit of the liquid level of the refrigerant R. For this reason, when the lower inner surface 4t of the lowermost tube 4b among the plurality of tubes 4 is positioned below the upper end portion 34a of the lower communication passage 34, the lower communication passage 34 accumulates. There is a possibility that the liquid-phase refrigerant R flows.

  In this heat exchanger 300a, the lowermost tube 4b of the plurality of tubes 4 is arranged such that its lower inner surface 4t is above the upper end portion 34a of the lower communication passage 34 (lower end portion 35b of the partition wall 35). It connects to the return path 32 so that it may become. For this reason, the refrigerant | coolant R can be distributed substantially equally to all the tubes 4 including the tube 4b.

  As described above, according to the heat exchanger 300a, the refrigerant R can be evenly distributed to the plurality of tubes 4. Further, in the inside of the inlet header 1, particularly in the return path 32, the liquid-phase refrigerant R once reaching the upper part of the return path 32 falls due to gravity, so the ratio of the liquid phase and the gas phase of the refrigerant R is in the entire return path 32. It becomes easy to be constant, and the state of the refrigerant R is homogenized including the state of gas-liquid mixing. According to this heat exchanger 300a, the plurality of tubes 4 are arranged in the return path 32 so as to avoid the influence of the dynamic pressure as much as possible and further avoid the influence of the region where the liquid refrigerant R accumulates. For this reason, the refrigerant R can be uniformly (equally) distributed by the tubes 4 including the state and amount of the refrigerant R.

  The refrigerant R uniformly distributed to each tube 4 in this manner exchanges heat with the air G and the like via the plurality of tubes 4 and the plurality of fins 3 and is output to the outlet header 2, and the system is supplied from the outlet 6. It flows out into 50 systems. Therefore, the heat exchange load in each tube 4 is made uniform, and the heat exchanger 300a with good heat exchange efficiency is obtained. Furthermore, it is not necessary to bend two or three-dimensionally into different shapes in order to distribute the refrigerant uniformly to each tube, and the heat exchange efficiency is good with a simple and compact configuration. Can be provided at a relatively low cost. Moreover, since the shape of each tube 4 can be made the same, generation | occurrence | production of the pressure loss difference in each tube 4 can be prevented, and a heat exchange efficiency can be improved also in this point.

  Furthermore, since the heat exchanger 300a can be easily downsized, the cooling system 50 including the heat exchanger 300a can be arranged in a compact manner. Further, since the heat exchanger 300a employs the discharge mechanism 11 that utilizes the suction effect (ejector effect) due to the differential pressure, the power source generally used in the heat exchanger, for example, the power of the compressor 51 is used. In addition, no new power source is required. Therefore, it is economical. In addition, by assigning a part of the pressure loss due to the expansion valve 53 to the discharge mechanism 11, it is possible to improve the heat exchange efficiency without impairing the economic efficiency of the system 50. If the expansion (pressure loss) by the discharge mechanism 11 is sufficient, the expansion valve 53 can be omitted.

  FIG. 7 shows a heat exchanger 300b according to the second embodiment of the present invention. This heat exchanger 300b can also be used as the evaporator 100 and / or the condenser 200 of the heat exchange system 50 as described above.

  In this heat exchanger 300 b, the inflow port 5 is provided below the forward path 31, and the discharge mechanism 11 including the orifice (nozzle, throttle part) 12 is provided between the forward path 31 and the inflow port 5. ing. Further, in the heat exchanger 300b, the lower communication passage 34 becomes the suction portion 14. Since the other configuration is the same as that of the first embodiment described above, the overlapping description will be omitted by attaching the same reference numerals to the drawings.

  In this heat exchanger 300 b, the orifice 12 is provided below the lower communication path 34, and the refrigerant R hardly accumulates in the lower communication path 34. Therefore, even if the lowermost tube 4b of the plurality of tubes 4 is connected to the return path 32 so that the lower inner surface 4t is lower than the upper end portion 34a of the lower communication path 34, The influence on uniformly distributing the refrigerant R to the plurality of tubes 4 is small.

  FIG. 8 shows a heat exchanger 300c according to the third embodiment of the present invention. This heat exchanger 300c can also be used as the evaporator 100 and / or the condenser 200 of the heat exchange system 50 as described above.

  In this heat exchanger 300 c, the inflow port 5 is provided below the forward path 31, and the discharge mechanism 11 is provided between the forward path 31 and the inflow port 5. The discharge mechanism 11 of the present example includes an ejector 16 including an ejector nozzle (throttle portion) 16a.

  In the heat exchanger 300c, the circulation path 10 includes a first straight pipe portion 61 that forms the forward path 31, a second straight pipe section 62 that forms the return path, and an upper portion 31a of the first straight pipe section 61. A U-shaped pipe including a first connection portion 63 extending substantially horizontally so as to connect the upper portion 32 a of the second straight pipe portion 62 and forming the upper communication path 33 is provided. The second of the lower communication passage 34 is formed so as to connect the U-shaped lower open side (so that the lower part 31b of the first straight pipe part 61 and the lower part 32b of the second straight pipe part 62 are connected). The connecting portion 64 extends substantially horizontally.

  In this example, the lower communication passage 34 is the suction portion 14. In addition, the inner wall of the first straight pipe portion 61 (the wall on the second straight pipe portion 62 side) and the inner wall of the second straight pipe portion 62 that forms the return path (the wall on the first straight pipe portion 61 side) Corresponds to the partition wall 35. Since the other configuration is the same as that of the first embodiment described above, the overlapping description will be omitted by attaching the same reference numerals to the drawings. Also in the heat exchanger 300c, the refrigerant R can be uniformly distributed to the plurality of tubes 4.

  In the present embodiment, the heat exchanger having the plate-like fins as the heat exchanger has been described as an example, but the fin shape is not limited to the plate shape. Moreover, the heat exchange part should just be able to perform heat exchange between refrigerant | coolants (heat exchange medium) and external fluids, such as air, and the shape and structure of a heat exchange part are also limited to these. It is not something. Further, it may be a heat exchanger provided with a plurality of inlet headers and outlet headers. Furthermore, the discharge mechanism is not limited to the orifice (throttle portion) and the ejector nozzle, but may be any one that includes a member that exhibits a similar function, such as a nozzle having a reduced discharge port area. . Moreover, although the heat exchanger of this invention connects a some tube to a return path, it does not exclude what connects a some tube to an outward path with a return path.

  The system of the present invention is not limited to air conditioning, but includes devices and systems that include various types of heat exchange as part of their functions, such as radiators, various cooling devices, and various refrigeration devices.

The figure which shows the outline of the heat exchange system containing a heat exchanger. The figure which shows the one part outline of the heat exchanger concerning the 1st Embodiment of this invention. The figure cut and shown along the III-III line in FIG. The figure which expands and shows the structure of the heat exchanger of FIG. The figure which expands and shows the area | region enclosed by the circle V in FIG. The figure which expands and shows the area | region enclosed by the circle | round | yen VI in FIG. The figure which shows the one part outline of the heat exchanger concerning the 2nd Embodiment of this invention. The figure which shows the outline of the heat exchanger concerning the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inlet header, 2 Outlet header, 4 Tube 4a Uppermost tube, 4s Upper inner surface 4b of uppermost tube 4b Lowermost tube, 4t Lower inner surface 11 of lowermost tube 11 Discharge mechanism, 12 Orifice, 16 Ejector 31 Outward, 31a Upper part of the forward path, 31b Lower part of the forward path 32 Return path, 32a Upper part of the return path, 32b Lower part of the return path 33 Upper communication path, 33a Lower end part of the upper communication path 34 Lower communication path, 34a Upper end 35 partition, 35a upper end of partition, 35b lower end of partition 50 system (heat exchange system), 51 compressor (pressurizer)
100 evaporator (evaporator), 200 condenser (condenser)
300a, 300b, 300c heat exchanger, R refrigerant (heat exchange medium)

Claims (10)

Multiple tubes,
An inlet header for distributing a heat exchange medium to the plurality of tubes;
A heat exchanger having an outlet header for recovering a heat exchange medium from the plurality of tubes,
The inlet header connects the forward path extending from the lower side to the upper side, the return path extending from the upper side to the lower side, the upper communication path connecting the upper part of the forward path and the upper part of the return path, and the lower part of the forward path and the lower part of the return path Including the lower communication passage,
The plurality of tubes are connected to the return path,
The upper inner surface of the uppermost tube among the plurality of tubes is located below the lower end of the upper communication path,
The inlet header further includes a discharge mechanism for blowing a heat exchange medium flowing into the inlet header upward from the lower part of the forward path to the forward path.   2. The heat exchanger according to claim 1, wherein a lower inner surface of a lowermost tube among the plurality of tubes is positioned above an upper end portion of the lower communication path.   The heat exchanger according to claim 2, wherein a discharge end of the discharge mechanism is located above an upper end portion of the lower communication path.   4. The heat exchanger according to claim 3, wherein the inlet header further includes an inlet for allowing a heat exchange medium to flow into the inlet header from a direction intersecting the forward path.   5. The heat exchanger according to claim 1, wherein the discharge mechanism includes an orifice.   The heat exchanger according to any one of claims 1 to 4, wherein the discharge mechanism includes an ejector. Multiple tubes,
An inlet header for distributing a heat exchange medium to the plurality of tubes;
A heat exchanger having an outlet header for recovering a heat exchange medium from the plurality of tubes,
The inlet header includes an outward path extending from the lower side to the upper side, a return path extending from the upper side to the lower side, and a partition wall separating the forward path and the return path,
The plurality of tubes are connected to the return path,
The upper inner surface of the uppermost tube among the plurality of tubes is located below the upper end of the partition wall,
The inlet header further includes a discharge mechanism for blowing a heat exchange medium flowing into the inlet header upward from the lower part of the forward path to the forward path.   8. The heat exchanger according to claim 7, wherein a lower inner surface of the lowermost tube among the plurality of tubes is positioned above a lower end portion of the partition wall.   A system comprising: the heat exchanger according to claim 1; and a medium supply system that supplies a heat exchange medium to the heat exchanger. An evaporator that cools an external fluid by heat exchange with the heat exchange medium, a pressure device that pressurizes the heat exchange medium recovered from the evaporator, and a heat exchange medium that is pressurized by the pressure device is cooled. A system having a condenser,
The system according to claim 1, wherein the evaporator and / or the condenser is a heat exchanger according to claim 1.

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