JPH0578742B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to an adsorption heat pipe that transfers heat by utilizing the refrigerant adsorption/desorption action of an adsorbent, and an adsorption heat pipe that utilizes the heat transfer action of the adsorption heat pipe. This invention relates to an adsorption refrigerator that performs refrigeration operation, heat pump operation, etc.

(Prior art) Adsorption refrigerators, which generate cold heat by utilizing the refrigerant adsorption and desorption effect of adsorbents, not only can effectively utilize low-grade heat sources such as factory waste heat, but also can be used in compressor type refrigerators. In comparison, there are fewer moving parts such as pumps, the equipment cost is relatively low, the operating cost can be kept low, and it has many advantages such as low operating noise.

FIG. 5 shows a cross section of an example of such an adsorption refrigerator.

This adsorption refrigerator consists of a horizontally long cylindrical vacuum container 1 filled with a required amount of refrigerant, a heat transfer tube 2 with fins through which a low-temperature heat medium obtained from a solar heat collector or the like passes, and a user side heat transfer tube 2. A linear manifold 3, 3' through which the medium passes and an integral evaporation condensing plate 4, 4' are horizontally housed at a required interval, and a cylindrical evaporation-proofing plate is placed around the evaporating condensing plate 4, 4'. It has a structure in which it is surrounded by shields 5 and 5', and a solid adsorbent 7 such as zeolite, activated carbon, activated alumina, or silica gel is attached to the opposing gap between the fins 6 on the outer periphery of the heat transfer tube 2. In,
When the liquid supplied from the heat source is passed through the heat transfer tube 2 and the solid adsorbent 7 is heated and desorbed, the refrigerant vapor desorbed from the solid adsorbent 7 is condensed on the surfaces of the evaporation condensation plates 4 and 4'. It sticks to this. Also,
During adsorption operation, when cooling water is flowed through the heat transfer tube 2 to cool the solid adsorbent 7, the solid adsorbent 7 absorbs the refrigerant vapor in the vacuum vessel 1 and the refrigerant on the surfaces of the evaporation and condensation plates 4 and 4'. When the refrigerant evaporates in the container 1, it removes heat from the evaporation condensation plates 4, 4' and passes through the linear manifolds 3, 3' that are integrated with the evaporation and condensation plates 4, 4'. It is designed to cool the side heating medium.

In this way, the user-side heating medium is cooled by the refrigerant adsorption/desorption action of the solid adsorbent 7, and is used for air conditioning of buildings, etc. (For example, see Japanese Patent Application Laid-Open No. 60-36852.) (Problems to be Solved by the Invention) However, in such a conventional adsorption refrigerator, a plurality of It houses heat exchanger tubes 2 and linear manifolds 3, 3' and integral evaporation condensation plates 4, 4', and each of these heat medium inlets and outlets is connected to external equipment such as a fan coil unit or cooling tower. When switching from operation to desorption operation, the temperature difference between the inlet and outlet of each heat exchanger increases, so it takes a considerable amount of time for these to equalize and produce a constant output, which reduces the operation cycle time. This resulted in a limit to the improvement of system efficiency.

That is, at the moment when the operation is switched from adsorption to desorption, the temperature near the inlet of the heat transfer tube 2 is high and the temperature near the outlet is low for a while, so the refrigerant desorbed from the solid adsorbent 7 near the inlet is transferred to the vicinity of the outlet. One of the reasons for this is that it is adsorbed by the solid adsorbent 7, resulting in energy loss.

In addition, in the case of a conventional adsorption refrigerator, the vacuum container 1
The size of the container 1 is considerable, and since it is necessary to maintain a single vacuum system inside the container 1, a considerable amount of pressure resistance is required for the container 1 itself, which leads to problems such as an increase in the weight of the device and a rise in manufacturing costs. It was hot.

The present invention has been made by focusing on the problems caused by the structure of such conventional adsorption refrigerators. The primary purpose is to construct a unitized adsorption heat pipe by maintaining a vacuum system of A second object of the present invention is to provide an adsorption refrigerator that eliminates energy loss due to the difference in entrance and exit temperatures by switching the flow of the heat medium passing through each fluid passage, thereby increasing the efficiency of the refrigeration system. purpose.

(Means for Solving the Problems) The configuration of the present invention for achieving the above object will be described with reference to FIGS. 1 and 2, which correspond to embodiments.

The adsorption heat pipe a, which is the first invention of this application, has a closed pipe 1 having a required length and having good thermal conductivity.
1, a solid adsorbent 12 is housed at one end thereof, a heat transfer fin 15 is housed at the other end, and a required amount of refrigerant is sealed inside the closed tube 11. is in a vacuum state.

Further, an adsorption refrigerator, which is a second invention of this application, uses a plurality of adsorption heat pipes a having the above configuration, and connects them to a plurality of adjacent fluid passages 23, 2.
The adsorption type heat pipe a penetrates through a heat insulating wall 22 placed at the boundary of the adsorbent 1.
The end _a1 on the side filled with 2 is inserted into the first fluid passage 23 through which the heat medium on the heat source side passes, and the other end side is inserted into the second fluid passage 23 through which the heating medium on the utilization side passes.
It is inserted in 4.

(Function) Therefore, the adsorption heat pipe a of the present invention having the above configuration heats the end a ₁ on the adsorbent filling side from the outside, and at the same time cools the end a ₂ on the heat transfer fin housing side. At this time, the solid adsorbent 12 is thermally desorbed, and the released refrigerant vapor is cooled and condensed on the surface of the fins 15, and is retained on the surface of the fins 15 in a liquid film state.

Next, when the adsorbent-accommodating side end a ₁ of the adsorption heat pipe a is cooled from the outside, the solid adsorbent 12 adsorbs the refrigerant vapor filling the internal space 13, so that it adheres to the surface of the heat transfer fin 15. The refrigerant liquid actively evaporates and takes away the heat of vaporization from the heat transfer fins 15, and the heat transfer fin housing side end a ₂ of the adsorption heat pipe a.
Cools the user-side heating medium that is in contact with the outer surface of the Therefore, the adsorbent accommodation side end a ₁ of the adsorption type heat pipe a is, for example, the heat source side heat medium flow path 2 of 80° C. or less.
For example, 30 ml of water obtained from a cooling tower etc. is inserted into the channel 24 into which the other end A ₂ is inserted.
When cooling water of ~32°C is supplied, the solid adsorbent 12 is desorbed in the adsorption heat pipe a,
When this is completed, the flow path is switched and the adsorbent accommodation side end a ₁ is inserted into the flow path 23 at the temperature of 30 to 32°C.
At the same time, the end of the heat transfer fin housing side
When the heat medium on the user side is supplied to the flow path 24 in which A ₂ is inserted, the refrigerant adsorption action of the solid adsorbent 12 starts within the adsorption heat pipe a, and the heat medium on the user side is cooled to an inlet temperature of 12°C. In order to satisfy the temperature condition of a general air conditioning system where the outlet temperature is around 7°C, cooling operation can be performed by supplying the utilization side heat medium to the fan coil unit disposed in the area to be air conditioned.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a sectional view showing an example of an adsorption heat pipe according to the present invention.

In the figure, 11 is a closed tube constituting the main body container of the adsorption heat pipe a, and 12 is the closed tube 11.
A granular solid adsorbent such as silica gel, zeolite, activated carbon, or activated alumina is filled toward one end of the internal space 13 of the solid adsorbent 12;
15 is a large number of heat transfer fins disposed biased toward the other end of the internal space 13 of the closed tube 11. The internal space 13 housing these is filled with a required amount of refrigerant liquid such as water, and the inside of the closed tube 11 is always kept in a vacuum state.

The above-mentioned adsorption heat pipe a is normally manufactured by a process as shown in FIG.

That is, as shown in FIG. 2A, one end of a metal pipe of a required length made of aluminum or copper, which is a base material for the closed tube 11 and has good thermal conductivity, is closed by span processing. A predetermined amount of granular solid adsorbent 12 is packed, and a corrosion-resistant wire mesh 14 made of stainless steel or the like previously formed into a dish shape or a test tube shape is press-fitted thereon, and the solid adsorbent 12 is inserted into the closed tube 11.
Fix it in contact with the inner surface of the Next, as shown in FIG. 2B, a perforated circular plate made of an aluminum plate or a copper plate with good thermal conductivity is press-molded, and a fin 15 is formed by forming annular rising portions 15a and 15b on the inner and outer peripheries. Closed tube 1 with multiple layers stacked
1, the open end of the closed tube 11 is inserted into the second tube.
It is drawn as shown in Figure C, and a thin tube 16 is attached to its tip by means such as welding (brazing).

Then, the thin tube 16 is connected to a deaerator 17 as shown in FIG. Pinch, cut off the excess portion, and braze the ends to seal the closed tube 11.

Note that the heat transfer fin 15 can freely set the fin pitch P by adjusting the height _h1 of the rising portion 15a on the outer periphery, and the upper surface of the fin 15 can be adjusted by the rising portion 15b on the inner periphery. Formed in a refrigerant liquid receptacle.

In addition to the above-mentioned method, the heat transfer fins 15 may be formed by forming a metal band plate made of aluminum or copper into a spiral shape having an outer diameter D slightly larger than the inner diameter of the closed tube 11, as shown in FIG. It is also possible to use slope-shaped fins, insert them into the closure tube 11 while squeezing them in a direction that reduces the outer diameter, remove external force, spring-huck the fins, and attach the fins in close contact with the inner surface of the closure tube 11. It is. Of course,
In this case, the fins 11 are corrugated perpendicular to the spiral direction, thereby increasing the surface area of the fins 11 and preventing the refrigerant liquid from flowing down naturally.

Furthermore, the amount of refrigerant sealed inside the closed pipe 11 is
The minimum amount necessary within the operating temperature range under the preset operating conditions of the refrigerator, that is, almost the entire amount of refrigerant is in the state of a liquid film of an appropriate thickness on the entire surface of the heat transfer fin 15 at the time of completion of desorption. The amount is defined as the amount that is retained and the entire amount is adsorbed by the solid adsorbent 12 when the adsorption is completed.

Therefore, based on the adsorption amount of the solid adsorbent 12, the surface area, number, etc. of the fins 15 are determined based on this, and also, based on the amount of refrigerant held by the fins 15, the adsorption amount of the solid adsorbent 12 is determined. The filling amount will be determined automatically.

FIG. 4 is a schematic diagram showing an example of an adsorption refrigerator according to the present invention. In the figure, 21 is the main body of the refrigerator, 2
2 is a heat insulating wall that partitions the inside of the main body 21 into a first fluid passage 23 and a second fluid passage 24,
A plurality of adsorption type heat pipes a shown in FIG. 1 are installed through the heat insulating wall 22 with the adsorbent housing side end a ₁ and the heat transfer fin housing side end a ₂ aligned. The end portions a ₁ and a ₂ project into the first and second fluid passages 23 and 24, respectively.

25 is an inlet port of the first fluid passage 23;
6 is an outlet port of the passage 23, 27 is an inlet port of the second fluid passage 24, and 28 is an outlet port of the passage.

The adsorption heat pipe and adsorption refrigerator of the present invention have the above-mentioned configurations. Next, to explain their function, first, the first fluid passage 23 is equipped with a solar collector or a waste heat recovery device. Heat medium on the heat source side obtained from a heat exchanger, etc. (e.g. water at 60-80℃)
is supplied to heat the adsorbent housing side end a ₁ of the adsorption heat pipe a to desorb the solid adsorbent 12 inside, and at the same time, the second fluid passage 24 is heated with 30 to 32°C generated by a cooling tower or the like. When cooling water is supplied to cool the heat transfer fin housing side end a ₂ of the adsorption heat pipe a, the refrigerant vapor discharged into the internal space 13 due to the desorption of the adsorbent 12 flows onto the surface of the heat transfer fins 15. It is cooled, condensed, and adheres to the surface in the form of a liquid film.

After desorbing the solid adsorbent 12 in this way, the flow path is switched, cooling water (30 to 32°C) is supplied to the first fluid path 23, and the adsorption heat pipe a
The solid adsorbent 12 is cooled by cooling the adsorbent housing side end _a1 of the solid adsorbent 12.
When the refrigerant vapor in the internal space 13 is adsorbed, the refrigerant held on the surface of the heat transfer fins 15 actively evaporates, and is vaporized from the heat transfer fins 15 and the closed tube 11 in contact with the heat transfer fins 15. In order to remove heat, the user-side heating medium flowing through the _second fluid passage 24 that is in contact with the outer surface of the heat transfer fin housing side end a 2 of the adsorption heat pipe a is cooled from an inlet temperature of 12°C to an outlet temperature of about 7°C. be done. Therefore, the second fluid passage 24
By circulating the user-side heat medium that has passed through and been cooled to a fan coil unit placed in an air-conditioned area such as a factory or office, the desired cooling operation can be performed.

Note that when switching from the adsorption operation to the desorption operation, a temperature difference occurs between the inlet and the outlet in the flow paths 23 and 24, but if we look at one adsorption heat pipe a, the closed pipe 11 Since the adsorbent accommodating side end a ₁ and the heat transfer fin accommodating side end a ₂ of the heat pipe a are heated or cooled almost all at once over their entire length, energy loss within the heat pipe a is almost negligible. In addition, between the heat pipes a, there is a difference in the adsorption/desorption process start time between the one near the inlet and the one near the outlet, but the heat medium in the fluid passages 23 and 24 Since the time required for replacing the solid adsorbent 12 can be much shorter than the adsorption/desorption cycle time of the solid adsorbent 12, the energy loss caused by this can be almost ignored.

In addition, in the above embodiment, the solid adsorbent 12
As a means for fixing the solid adsorbent to the inner surface of the closed tube 11, a case has been described in which the wire mesh 14 is used. It is also possible to glue it to the inner surface. Further, if necessary, a highly thermally conductive substance such as copper powder may be mixed into the solid adsorbent 12 and the binder.

Further, the heat transfer fins 15 can also be constructed by fixing wire fins to the inner surface of the closed tube 11 by means of brazing or the like, in addition to the plate-type fins shown in the drawings.

(Effects of the Invention) As described above, the adsorption heat pipe of the present invention has a solid adsorbent housed inside a closed pipe of a required length with good thermal conductivity, biased toward one end thereof, and , heat transfer fins are housed on the other end side in contact with the inner surface of the closed tube, and a required amount of refrigerant is sealed in the internal space of the closed tube, and the internal space is brought into a vacuum state. Since the important operating parts of the refrigeration system are built into a single closed pipe and are unitized, the vacuum system for moving the refrigerant is small, and energy loss due to uneven temperature can be greatly reduced. Since it can be constructed with a thin pipe, it is easy to maintain an airtight state and manufacture it, and it has the excellent effect of suppressing the rise in manufacturing costs of adsorption refrigerators using it.

Further, the adsorption refrigerator of the present invention uses a plurality of adsorption heat pipes having the above-mentioned configuration, these are installed through the partition walls of a plurality of adjacent fluid passages, and the adsorption heat pipe has an adsorbent housing side. One end of the heat transfer fin is inserted into a fluid passage through which a heating medium passes through on the heat source side, and the other end on the heat transfer fin housing side is inserted into a fluid passage through which a heating medium on the user side passes. Since the heat transfer function of the pipe is used to transfer heat between multiple fluid passages, when each fluid passage is switched and adsorption operation and desorption operation are performed alternately, there is a Even when a large temperature difference occurs, each adsorption heat pipe suffers almost no energy loss due to temperature imbalance, greatly improving the system efficiency of the entire device.
Since heat transfer between channels takes place in the internal space of the adsorption heat pipe, the main body of the refrigerator does not need to be a separate vacuum container, and high pressure resistance and airtightness are not required, making manufacturing and maintenance extremely easy. It has the excellent effect of making things easier.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of the adsorption heat pipe of the present invention, Fig. 2 A to D are explanatory diagrams showing an example of the manufacturing process of the adsorption heat pipe, and Fig. 3 is a cross-sectional view showing an example of the adsorption heat pipe according to the present invention. FIG. 4 is a perspective view showing an example of an applicable heat transfer fin, FIG. 4 is a schematic diagram showing an example of an adsorption refrigerator according to the present invention, and FIG. 5 is a sectional view of a conventional adsorption refrigerator. a... Adsorption heat pipe, 11... Closed pipe,
12...Solid adsorbent, 13...Inner space, 15...
...Heat transfer fin, 23...Heat source side heat medium flow path, 24...
...Using side heat medium flow path, a ₁ ...Adsorbent accommodation side end, a ₂
...The end of the heat transfer fin housing side.

Claims (1)

[Scope of Claims] 1. A solid adsorbent is housed inside a closed tube of a required length with good thermal conductivity, biased toward one end thereof, and a solid adsorbent is housed inside the closed tube at the other end. 1. An adsorption heat pipe characterized in that heat transfer fins are disposed in contact with each other, and a required amount of refrigerant is sealed in the internal space of the closed tube to create a vacuum state in the internal space. 2. The adsorption heat pipe according to claim 1, wherein the amount of refrigerant sealed in the closed pipe is set to the minimum amount necessary within the operating temperature range under certain operating conditions. 3. The adsorption heat pipe according to claim 1 or 2, wherein the solid adsorbent is housed in the internal space in direct contact with the inner surface of the closed tube. 4 A solid adsorbent is housed inside a closed tube of a required length with good thermal conductivity, biased toward one end, and heat transfer fins are placed at the other end in contact with the inner surface of the closed tube. At the same time, a required amount of refrigerant is sealed in the internal space of the closed pipe, and a plurality of adsorption heat pipes are used to create a vacuum state in the internal space, and these are connected to the walls between the adjacent fluid passages. At the same time, the adsorbent housing side end of the adsorption heat pipe is inserted into the fluid passage through which the heat source side heat medium passes, and the other heat transfer fin housing side end is inserted into the user side heat medium. An adsorption refrigerator characterized in that each of the adsorption refrigerators is inserted into a fluid passage through which the refrigerator passes.