JP3545025B2 - Fin type adsorbent heat exchanger - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a fin-type adsorbent heat exchanger used in an adsorption refrigerator.
[0002]
[Prior art]
Conventionally, adsorption refrigerators have an adsorption / desorption effect by heating or cooling a solid adsorbent such as silica gel, activated carbon, and zeolite under vacuum conditions in which a refrigerant such as water or alcohol evaporates and condenses. The refrigeration effect is brought out by the action at that time.
Heat exchange / heating of this adsorbent is performed by cooling and heating with a heat medium via a heat transfer surface to perform heat exchange. However, unlike heat exchange between general fluids, the adsorbent forms a solid (often spherical). Since the heat transfer is performed by the point contact with the heat transfer surface and the contact between the solids, it is difficult to improve the heat transfer efficiency. Therefore, many heat transfer surfaces are required.
On the other hand, if the adsorbent is filled while surrounded by the heat transfer surface, the refrigerant vapor adsorbed and desorbed by the adsorbent must pass through the gap between the adsorbents present on both sides of the heat transfer, so that the passage resistance is reduced. Occurs, and performance is hardly exhibited.
[0003]
Therefore, on the heat transfer surface, for example, as shown in Japanese Patent Application Laid-Open No. 62-91763, circular fins made of aluminum or the like whose fin height is specified are provided at a predetermined pitch around a heat transfer tube through which a heat medium flows. A structure in which an adsorbent is filled between the fin pitches, and the fin outer side is covered with a wire mesh knitted with an extra-fine wire mesh for preventing the adsorbent from falling off for each heat transfer tube, and covers the entire length of the heat transfer tube. It has become.
[0004]
However, in the above configuration, in order to secure the required amount of the adsorbent according to the capacity, the number of tubes is increased, and the heat transfer tube array of the tube plates at both ends for fixing the heat transfer tubes also has a refrigerant vapor passage at the time of adsorption and desorption. Since the heat transfer tube is determined to include the heat transfer tube, there is a disadvantage that the heat exchanger that collects the entire heat transfer tube becomes large.
However, since the adsorbent heat exchanger of this type is manufactured for each heat transfer tube, the cost increases.
[0005]
In order to solve such a drawback, a plurality of heat transfer tubes 40 extending in the horizontal direction are arranged vertically in a row as shown in FIG. 2, and a number of plate-like aluminum fins 41 are fitted through predetermined gaps. At the same time, the fin interval is filled with a particulate adsorbent 42, and a thin wire mesh 43 of a very fine wire mesh (for example, about 40 mesh, depending on the particle size, is covered) on the fin surface to prevent the adsorbent from falling off. 42 is prevented from falling out or moving outside the fin surface or the interval.
[0006]
And in the said technique, in order to prevent the adsorbent from falling off, the fins are wound from the outside with a wire mesh knitted with a very fine wire mesh to cover the heat exchanger. Since they cannot be in close contact with each other, a method is required in which expanded metal or the like having coarser eyes from the outside is used to increase the degree of closeness of the wire mesh.
[0007]
[Problems to be solved by the invention]
However, it is difficult to increase the degree of adhesion of a thin wire mesh evenly over the entire surface of the filler even with an expanded metal or the like, and after taking measures such as tightening to prevent distortion in some places, it is difficult to save time and effort. Was.
Using a relatively strong reinforcing agent such as expanded metal to hold down the wire mesh from above increases weight, increases the ineffective heat capacity, increases the amount of heat required during regeneration and cooling of the adsorbent, and increases the coefficient of performance. Had the disadvantage of becoming worse.
[0008]
In the prior art shown in FIG. 2, when a large capacity adsorbent heat exchanger is required, the size of the adsorbent heat exchanger for each sheet is increased, and the heat exchanger is assembled in multiple layers. However, if the size is increased, the adsorbent will bend due to its own weight, and the adsorbent will fall off or move from the fin portion, and the function of the adsorbent will be greatly reduced.
Furthermore, even when the heat exchanger is assembled as a whole, there is a partial deflection during lifting and moving during assembly, which creates a gap between the wire mesh and the fin surface, and the small sorbent drops down. There was a drawback that it would.
[0009]
However, the prior art shown in FIG. 2 takes a configuration in which a thin wire mesh is covered around the fins and then covered with expanded metal. However, economies of scale could not be exhibited, and as a result, it was difficult to reduce costs and greatly improve performance.
[0010]
An object of the present invention is to provide a fin-type adsorbent heat exchanger that can be easily and inexpensively manufactured and that can easily exhibit economies of scale in view of the drawbacks of the related art.
Another object of the present invention is to improve the efficiency of adsorbent regeneration and cooling compared to the prior art without the adsorbent dropping or moving from the fin portion and the function of the adsorbent being significantly reduced. It is an object of the present invention to provide a fin-type adsorbent heat exchanger capable of improving the coefficient of performance.
[0011]
[Means for Solving the Problems]
According to the present invention, as shown in FIG. 1, a large number of plate-like fins 2 are integrally fitted to a plurality of heat transfer tubes 4 arranged in a row via a predetermined gap, as shown in FIG. And a plurality of heat exchange units 10 having upper and lower surfaces of the plate fin portion 2A sandwiching adsorbent drop-prevention wire meshes 5a and 5b. At the same time, an elastic body 6 having good thermal conductivity and capable of passing fluid is interposed between the units 10 so as to apply an elastic force over substantially the entire area of the wire meshes 5a and 5b. Characterized in that the units 10 are held together via the.
Preferably, a fine expanded metal or a punched metal is provided on the bottom surface of the wire mesh 5a for preventing the adsorbent from falling off at the lowermost layer or on the upper surface of the wire mesh 5b for preventing the adsorbent from falling off at the uppermost layer. It is good to arrange 7.
It is preferable that the elastic body 6 is a corrugated lattice made of a spring wire.
[0012]
[Action]
According to such technical means, every time the heat exchanging units 10 are stacked, the entirety can be easily and quickly assembled by assembling the heat exchange units 10 while keeping the pitch interval, the movement of the adsorbent, and the prevention of falling off.
Further, the elastic body 6 holding the spring reaction force is sandwiched between the stacked heat exchange units 10, and the corrugated sheet pitch between the fins of the upper and lower units 10 is approximately 3 cm through the wire meshes 5a and 5b. When the entire adsorbent is completed, the wire nets 5a and 5b can be brought into close contact with the upper surface of the fin 2 so that the filled adsorbent does not move or spill when the entire adsorbent heat exchanger is completed.
Further, only one elastic body 6 is required for a pair of upper and lower adsorbent heat exchange units, and the elastic body is made of a spring wire, so that the resistance at the time of adsorption and desorption of steam is small, and the specific heat The heat capacity of the elastic body 6 can be small.
Further, since the elastic body 6 interposed between the units 10 can be used because it has a small apparent specific heat and a light weight, the amount of ineffective heat during regeneration and cooling can be reduced, thereby improving the coefficient of performance of the adsorption refrigerator. Can be.
Therefore, according to such a technical means, when the whole is assembled, none of the heat exchange units 10 moves the adsorbent 3 and does not fall off from the fin portions 2A, and conventionally, a holding plate is provided for each fin portion 2A. What is required is that only one elastic body 6 is interposed between the units 10, so that the weight is reduced and the heat capacity is reduced.
[0013]
【Example】
An adsorbent heat exchanger according to an embodiment of the present invention will be described with reference to FIGS. 1 and 3 along a manufacturing procedure.
Although the heat exchanger adopts a horizontal stacking method of the heat exchange units 10 as a manufacturing procedure, it is optional to use the heat exchange units 10 horizontally or vertically in use. The size of the cooling tube, the size / shape of the plate-like fins, and the type of the adsorbent can be arbitrarily selected, and the following embodiments are merely examples.
First, a plurality of fin heat exchangers are formed into a substantially square shape by fitting a large number of plate-like fins 2 through a predetermined gap integrally with a plurality of heat transfer tubes 4 arranged in a row. prepare.
[0014]
Next, the rectangular punching metal 7 is placed on a horizontal table (not shown), and a 40-mesh wire mesh 5a having a mesh size enough to prevent the adsorbent 3 from falling off is placed thereon. The mesh of the wire meshes 5a and 5b is determined by the particle size of the adsorbent 3 to be filled. The punching metal 7 is provided for the purpose of suppressing the swelling below the 40 mesh wire mesh 5a when the adsorbent 3 is filled.
After disposing the fin heat exchanger on the wire mesh 5a, the periphery of the outer frame 11 of the fin heat exchanger, the wire mesh 5a and the punching metal 7 are integrally fixed by spot welding or the like.
[0015]
Thereafter, the adsorbent 3 flows into the fin portion 20 and is sufficiently filled so that it does not protrude from the upper portion of the fin 2. At this time, it is preferable that the filling be performed while vibrating with a vibrator or the like, since the filling can be easily performed to every corner.
After completion of the filling, the upper surface of the fin portion of the unit 10 is sealed using the 40 mesh wire mesh 5b, and the wire mesh 5b and the unit outer frame 11 are fixed by spot welding or the like, thereby completing the first-stage unit 10A.
[0016]
The uppermost unit 10 is manufactured in the same manner as the first-stage unit 10A. However, at the time of lamination described later, the punching metal 7 is arranged so as to be located on the upper surface side of the wire mesh 5b.
In the heat exchange unit 10B located at an intermediate portion except for the uppermost position and the lowermost position, the fin heat exchanger filled with the adsorbent 3 is sandwiched between the pair of wire nets 5a and 5b without providing only the punching metal 7. Formed by spot welding.
After each heat exchange unit 10 is manufactured as described above, the frame fixing bolts 8 are passed through the four evens of the outer frame 11 of the first-stage heat exchange unit 10A, and the pipe seat 9 is inserted into each of the four bolts 8. Attach it.
[0017]
The pipe seat 9 functions as a washer for adjusting the interval between the units 10 so that the gap L between the units 10 is set to be constant. The distance L is set to a minimum value such that the vapor passage for adsorption and desorption is not blocked, for example, about 10 mm.
Next, before stacking the second-stage heat exchange unit 10B, when the free dimension L1 is higher than the interval dimension L and pressed on the upper surface of the wire mesh 5b of the first-stage heat exchange unit 10A at the interval dimension L, The corrugated elastic body 6 set so as to exert a spring force is overlaid.
The elastic body 6 is formed in a coarse corrugated sheet shape using a spring wire having good heat conductivity, and has a small heat capacity, and has a large corrugated sheet such that its top and bottom cover the entire area of the fin portion 2A. It is preferable to form a lattice.
[0018]
Then, the second-stage heat exchange unit 10 is inserted into the frame fixing bolt 8 from above the elastic body 6 and stacked and arranged. At this stage, the interval dimension L between the upper and lower heat exchange units 10 and the heat exchanger defined by the pipe seat 9 is larger than the free dimension L1 of the elastic body 6 (defined by the size and material, but approximately 15 mm to 20 mm). Since the elastic body 6 is set to a small value of about 10 mm, the elastic body 6 sufficiently sinks, and at the same time, the tension acts on the metal nets 5a and 5b by urging the corresponding fin portions 2A of the respective units 10 with elastic force.
[0019]
At this time, if the corrugated plate pitch interval P of the elastic body 6 is too wide, the wire nets 5a and 5b are loosened at the time of completion, and the adsorbent 3 moves on the fin portion 2A or spills out of the fin portion 2A. Therefore, a corrugated plate pitch of about 30 mm is appropriate. In addition, if the wire of the elastic body 6 is thick or clogged, the resistance of the steam passage and the apparent specific heat of the elastic body 6 increase, so that the elastic body 6 is manufactured with a reduced free dimension height. There is a limit in increasing the diameter of the spring wire.
[0020]
Hereinafter, similarly to the above, the second-stage and third-stage heat exchange units 10 are stacked and arranged via the elastic body 6. The punched metal 7 is fixed on the wire mesh 5b on the upper surface of the uppermost unit 10, and the elastic body 6 is interposed on the wire mesh 5a on the bottom face as described above.
Then, after all the heat exchange units 10 are stacked and arranged, the nut 81 is tightly tightened to the holding bolt 8 to be fixed.
[0021]
In particular, when the number of stages is large and the weight is large, simply fixing the outer frame 11 of the heat exchanger 10 with the bolts 8 may result in insufficient strength. May be.
Although not shown in the figure, the connection of the heat transfer tube 4 to the header and the method of switching between the cooling water and the heat medium for operating as a system are the same as those in the related art.
[0022]
【The invention's effect】
According to the present invention as described above,
In view of the drawbacks of the prior art, the present invention makes it possible to obtain a fin-type adsorbent heat exchanger that can be manufactured easily and at low cost and can easily exhibit the merits of scale. The efficiency of adsorbent regeneration and cooling is greatly increased as compared with the above-mentioned prior art, and the coefficient of performance can be improved without drastically lowering and lowering the function of the adsorbent.
Therefore, according to the present invention, it is possible to establish a method of manufacturing a high-performance adsorption heat exchanger using a low-cost conventional plate heat exchange unit.
By using the lightened adsorbent heat exchanger manufactured in this way, it is possible to improve the performance of the adsorption refrigerator.
And so on.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a main configuration of an adsorbent heat exchanger according to an embodiment of the present invention.
FIG. 2 is a perspective view showing a configuration of a main part of an adsorbent heat exchanger according to the related art.
FIG. 3 is an enlarged perspective view showing a fin portion of FIG. 1;
[Explanation of symbols]
Reference Signs List 10 heat exchange unit 2 plate fin 2A fin part 3 adsorbent 4 heat transfer tube 5a, 5b mesh wire mesh 6 elastic body 7 punching metal (for lowermost reinforcement)
8 Frame fixing bolt 9 Tube seat (Heat exchange unit spacing adjustment washer)

Claims (3)

A plurality of plate-like fins are fitted into a plurality of heat transfer tubes arranged in a row, with a predetermined gap therebetween, and the fin interval is filled with a particulate adsorbent. A plurality of heat exchange units sandwiching an adsorbent drop-prevention wire mesh are stacked one above the other, and a good heat conductivity between the units can be applied to the elastic force over substantially the entire area of the wire mesh. A fin-type adsorbent heat exchanger, wherein an elastic body through which a fluid can pass is interposed, and the units are held via the elastic body. An expanded metal or a punching metal is disposed on the bottom surface of the wire mesh for preventing the adsorbent from falling off at the lowermost layer or on the upper surface of the wire mesh for preventing the adsorbent from falling off at the uppermost layer. Item 6. A fin type adsorbent heat exchanger according to item 1. 2. The fin type adsorbent heat exchanger according to claim 1, wherein the elastic body is a corrugated open lattice body made of a spring wire.

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