JPH10332222A - Absorption cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorption cooling device which is free from high temperature oxidation due to overheat of a fin even if the fin is provided on a wall face, by employing a structure wherein exhaust gas is made to flow along the wall face of an annular cylindrical container part of a heating container. SOLUTION: An outer peripheral fin 25 is omitted at an outer side of a lower part 25a. Therefore, the most upstream end part of the outer peripheral fin 25 is constituted only of an outer peripheral wall face 23b side. The outer peripheral wall face 23b has a good heat sink property, and an extreme high temperature is not reached so that corrosion of the outer peripheral fin 25 due to high temperature oxidation is not caused. In a downstream side an outer side is exposed to exhaust gas, but, since temperature of the exhaust gas is lowered due to progress of heat exchange, high temperature oxidation hardly occurs on the outer peripheral fin 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling apparatus using an absorption refrigeration cycle, and more particularly to a technique for heating an absorption liquid with high-temperature exhaust gas.

[0002]

2. Description of the Related Art FIG. 7 shows an example of the prior art. Heating vessel J2 for heating the absorbing liquid by the exhaust gas of combustion device J1
In addition to covering the burner J3 from above, it has a substantially U-shaped container shape having an annular annular cylindrical container J4, and the exhaust gas flows through the inner peripheral exhaust passage J5 and the outer peripheral exhaust passage J6 of the annular cylindrical container J4. What is provided so that it may flow is known. On the outer peripheral wall J7 of the annular cylindrical container J4,
Outer peripheral fins J8 are joined to efficiently transfer the heat of the exhaust gas to the annular cylindrical container J4.

[0003]

Exhaust gas flows upward from the bottom along the outer peripheral wall J7 of the annular cylindrical container J4. At this time, the lower end of the outer peripheral fin J8 touches a high-temperature exhaust gas whose heat absorption has not progressed as compared with the upper part. As a result, the outer end of the outer fin J8 has a drawback that heat is drawn to the outer wall surface J7 (slow heat transfer) at a lower temperature than the inner end, so that the temperature becomes high and corrosion by high-temperature oxidation proceeds.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to adopt a structure in which exhaust gas flows along the wall surface of an annular cylindrical container portion of a heating container, and to provide fins on the wall surface. However, an object of the present invention is to provide an absorption cooling device that does not cause high-temperature oxidation due to overheating of the fin.

[0005]

[Means for Solving the Problems]

According to a first aspect of the present invention, there is provided an absorption-type cooling apparatus comprising: a burner for burning fuel; a combustion apparatus having a combustion fan for forcibly sending air for combustion to the burner; A heating vessel to which the liquid is supplied,
A regenerator that evaporates part of the absorbing liquid, a condenser that cools and liquefies the vaporized refrigerant generated by the regenerator, and an evaporator that cools the heat medium by evaporating the liquefied refrigerant liquefied by the condenser under low pressure. An absorber for absorbing the vaporized refrigerant evaporated by the evaporator into the absorbent, and an absorption refrigeration cycle including a solution pump for pressure-feeding the absorbent absorbing the vaporized refrigerant in the evaporator to the regenerator. .

[0006] The heating vessel has a substantially U-shaped cross-sectional shape provided with a ring-shaped cylindrical vessel portion while covering the burner from above, and the combustion device discharges exhaust gas generated by the burner into the vessel. An exhaust passage that flows along the wall surface of the annular cylindrical container portion; and a fin that efficiently transfers heat of exhaust gas to the annular cylindrical container portion on the wall surface of the annular cylindrical container portion. The most upstream end is characterized in that a side far from the wall surface is missing.

According to a second aspect of the present invention, in the absorption type cooling apparatus according to the first aspect, the most upstream end portion of the fin is cut obliquely so that the width of the fin becomes smaller toward the downstream side. It is characterized by the following.

According to a third aspect of the present invention, there is provided an absorption-type cooling device, which includes a burner for burning fuel, a combustion device provided with a combustion fan for forcibly sending combustion air to the burner, and a heating device which is heated by the combustion device. A regenerator for vaporizing a part of the absorbing liquid, a condenser for cooling and liquefying the vaporized refrigerant generated in the regenerator, and a liquefied refrigerant for liquefying in the condenser. An evaporator that evaporates under a low pressure to cool the heat medium, an absorber that absorbs the vaporized refrigerant evaporated by the evaporator into an absorbent, and pumps the absorbent that has absorbed the vaporized refrigerant in the evaporator to the regenerator. An absorption refrigeration cycle including a solution pump.

The heating container has a substantially U-shaped cross-sectional shape which covers the burner from above and has an annular tubular container portion. The combustion device converts the exhaust gas generated by the burner into An exhaust passage that flows along the wall surface of the annular cylindrical container portion is provided.The wall surface of the annular cylindrical container portion includes a fin that efficiently transfers heat of exhaust gas to the annular cylindrical container portion. A restriction plate is provided upstream of the fins for guiding exhaust gas to the wall surface side of the annular cylindrical container portion.

According to a fourth aspect of the present invention, in the absorption cooling apparatus of the third aspect, the exhaust passage has an exhaust port for collecting exhaust gas and discharging the exhaust gas to the outside, and the restricting plate is close to the exhaust port. The exhaust area through which the exhaust gas passes is reduced, and the exhaust area through which the exhaust gas passes far from the exhaust port is increased.

[0011]

[Action and effect of the invention]

[Function and Effect of Claim 1] Since the most upstream end of the fin is provided so as to be cut off on the side farther from the wall surface than the downstream side, the amount of heat of the exhaust gas received by the most upstream end of the fin is smaller than that of the fin. Only on the wall side. The fins on the wall surface side conduct heat transfer to the wall surface and have good heat dissipation, so that the fins do not become extremely high in temperature and corrosion due to high-temperature oxidation is suppressed.

According to the second aspect of the present invention, since the upstream side where the temperature is likely to be high becomes larger, the fin has a portion cut off according to the possibility of the high temperature oxidation. While preventing this, it is possible to minimize the decrease in the heat exchange efficiency.

According to the third aspect of the present invention, a restriction plate for guiding the exhaust gas to the wall surface is provided in the exhaust passage on the upstream side of the fin, so that the far side from the wall surface of the fin becomes a blind spot of the flow of the exhaust gas. Therefore, the amount of heat received on the side far from the wall surface of the fin is reduced, and the side far from the wall surface of the fin does not become extremely high in temperature, so that corrosion due to high-temperature oxidation is suppressed. In addition,
The fins on the wall surface to which the exhaust gas flows receive heat from the wall surface and have good heat dissipation, so that the fins do not become extremely high in temperature and corrosion due to high-temperature oxidation is suppressed. In addition, since the effect of the blind spot by the limiting plate becomes smaller toward the downstream, the flow of the exhaust gas also hits the fins farther from the wall surface, but heat exchange with the absorbing liquid proceeds and the temperature of the exhaust gas decreases. For,
There is no problem that the fin is oxidized at high temperature.

According to a fourth aspect of the present invention, the restriction plate provides a small exhaust area for exhaust gas near the exhaust port and a large exhaust area for exhaust gas far from the exhaust port. Thereby, the amount of exhaust gas in the entire circumference of the exhaust passage is made uniform, and local overheating of the fins can be further prevented.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described based on examples and modifications. [Structure of the First Embodiment] In this embodiment, the absorption cooling device of the present invention is applied to an air conditioner, and will be described with reference to FIGS. FIG. 2 is a schematic configuration diagram of the air conditioner of the present embodiment.

(Schematic Description of Air Conditioning Apparatus 1) An air conditioning apparatus 1 shown in this embodiment is a relatively small one used for home use or the like, and has an outdoor unit A disposed outdoors and an outdoor unit A disposed indoors. And an indoor air conditioner B. The outdoor unit A cools the combustion device 2 that heats the absorbing liquid (a lithium bromide aqueous solution in the present embodiment) and cold / hot water (a heat medium for cooling and heating the room, water in the present embodiment) used for indoor air conditioning. Alternatively, a double effect absorption refrigeration cycle 3 for heating and an absorption refrigeration cycle 3
And a cooling tower 4 for cooling cooling water mainly used for cooling a vaporized refrigerant (steam in this embodiment). Each electric functional component mounted on the air conditioner 1 is controlled by the control device 5 arranged in the outdoor unit A.

(Explanation of Combustion Apparatus 2) The combustion apparatus 2 of this embodiment generates heat by burning gas as a fuel, and heats the heating vessel 10 of the absorption refrigeration cycle 3 by the generated heat. A gas combustion device that heats a low-concentration absorbing liquid (hereinafter referred to as a low liquid) supplied to a container 10, a gas burner 11 that burns gas, a gas supply pipe 12 that supplies gas to the gas burner 11, and a gas burner 11. It comprises a combustion fan 13 for supplying air for combustion. The gas supply pipe 12 has a gas on-off valve 12 for opening and closing the gas supply pipe 12.
a and a gas amount control valve 12b for adjusting the combustion amount by adjusting the gas supply amount. The details of the structures of the combustion device 2 and the heating vessel 10 will be described later.

(Explanation of Absorption Refrigeration Cycle 3) The absorption refrigeration cycle 3 includes a heating vessel 10 heated by the combustion device 2, and the low liquid supplied into the heating vessel 10 is heated to reduce the temperature. A high-temperature regenerator 15 that evaporates (evaporates) a refrigerant (water) contained in the liquid into a medium-concentration absorbing liquid (hereinafter, medium liquid), and utilizes heat of condensation of the vaporized refrigerant in the high-temperature regenerator 15, A low-temperature regenerator 16 that heats an intermediate liquid supplied from the high-temperature regenerator 15 using a pressure difference, vaporizes a refrigerant contained in the intermediate liquid, and turns the intermediate liquid into a high-concentration absorbing liquid (hereinafter, high liquid). And a condenser 17 for cooling and liquefying the vaporized refrigerant (steam) from the high-temperature regenerator 15 and the low-temperature regenerator 16
And an evaporator 18 for evaporating the liquefied refrigerant (water) liquefied in the condenser 17 under a pressure close to vacuum, and an evaporator 18
An absorber 19 for absorbing the vaporized refrigerant evaporated in the high-temperature liquid obtained by the low-temperature regenerator 16 and a solution pump 2 for pressure-feeding the low liquid absorbed by the vaporized refrigerant in the absorber 19 to the heating vessel 10
0.

In the absorption refrigeration cycle 3 of the present embodiment, in addition to the cooling operation by the above-described operation, in order to perform the heating operation, the high-temperature absorption liquid heated by the combustion device 2 is sent to the evaporator 18. The air conditioner includes a heating pipe 21 for guiding and a switching valve 22 for opening and closing the heating pipe 21. The cooling / heating switching valve 22 is opened during the heating operation to guide the high-temperature absorbing liquid to the evaporator 18,
The hot and cold water supplied to the indoor air conditioner B is heated.

(Explanation of operation of cooling operation) When an instruction for cooling is given to the control device 5, the operation of each electric functional component causes
The combustion device 2 and the absorption refrigeration cycle 3 operate. In the absorption refrigeration cycle 3, when the combustion device 2 heats the heating vessel 10, the high-temperature regenerator 15 removes the vaporized refrigerant and the middle liquid from the low liquid, and the low-temperature regenerator 16
Vaporized refrigerant and high liquid are taken out of the middle liquid.

The vaporized refrigerant taken out by the high-temperature regenerator 15 and the low-temperature regenerator 16 is condensed and liquefied by the condenser 17 and then dispersed in the evaporator 18 to be vaporized from the cold and hot water supplied to the indoor air conditioner B. Take away heat and evaporate. Then, the cold and hot water cooled by the evaporator 18 is supplied to the indoor air conditioner B to cool the room.

The vaporized refrigerant evaporated in the evaporator 18 flows into the absorber 19. In the absorber 19, the low temperature regenerator 1
The high liquid taken out at 6 is sprayed, and the vaporized refrigerant flowing from the evaporator 18 is absorbed by the sprayed high liquid. Note that the absorption heat generated when the vaporized refrigerant is absorbed by the high liquid is absorbed by the cooling water supplied from the cooling tower 4, so that a decrease in absorption capacity is prevented. And the absorber 19
The high liquid that has absorbed the vaporized refrigerant in step (1) becomes a low liquid, is sucked by the solution pump 20, returned to the heating vessel 10 again, and repeats the above cycle.

(Description of Heating Vessel 10)
As shown in FIG. 1, a stainless steel container having a substantially U-shaped cross section that covers an upper part of the burner 11 is connected to an upper part of an outlet cylinder 10 a. The annular cylindrical container portion 23 of the heating container 10 having an annular shape is formed inside the inner peripheral wall surface 23a and the outer peripheral wall surface 23a.
b, the combustion gas flows along the outside, and on the outer peripheral wall surface 23b of the annular cylindrical container portion 23, as shown in FIG. 1, for the purpose of improving the heat exchange rate between the exhaust gas and the heating container 10,
Outer peripheral fins 25 made of a material having excellent thermal conductivity (for example, copper) are joined by joining means such as brazing.

(Description of Combustion Apparatus 2) The combustion apparatus 2 causes the air supply passage 26 for sending the air flow generated by the combustion fan 13 to the burner 11 and the exhaust gas generated by the combustion in the burner 11 to contact the heating vessel 10. And an exhaust passage 28 leading to the exhaust port 27. The exhaust passage 28 is connected to the burner 11
Exhaust gas generated in the inner peripheral wall surface 2 of the annular cylindrical container portion 23
An inner exhaust passage 28a that flows downward from above along 3a, and an outer exhaust passage 28b that flows upward from below along the outer peripheral wall surface 23b of the annular cylindrical container portion 23 are provided.

(Description of Outer Fins 25) Outer Fins 25
Is formed by joining corrugated fins obtained by bending a thin copper plate into a large number of waves along the outer peripheral wall surface 23b. A lower portion 25a (corresponding to the most upstream end portion) of the outer peripheral fins 25 is
The outer peripheral side is cut off and provided compared to the upper part 25b. Specifically, in the present embodiment, the outer periphery of the lower end of the outer peripheral fin 25 is provided in a shape cut obliquely (see FIG. 3). The shape of the cut is cut diagonally so that the cut-off width becomes smaller toward the downstream side. For example, as shown in FIG. 4, the cut is cut into a width of 4 mm and a length along the flow direction of 40 mm. ing.

[Effects of the embodiment] The outer peripheral fin 25 is provided with the lower end outer peripheral side thereof being cut off.
The amount of heat of exhaust gas received by the outer peripheral side of the lower end of the
5 only on the outer peripheral wall surface 23b side. This outer peripheral wall 23b
The outer peripheral fin 25 on the side is transferred from the outer peripheral wall surface 23b to the internal absorbing liquid and has good heat dissipation, so that the temperature does not become extremely high and corrosion due to high-temperature oxidation is suppressed. In addition, the lower side, which is likely to be heated to a high temperature, is formed in a shape that is cut larger, so that the outer peripheral fin 25 has a shape in which a portion corresponding to the possibility of high-temperature oxidation is cut. A decrease in the efficiency of heat exchange between the liquid and the absorbing liquid can be minimized.

[Second Embodiment] FIG. 5 shows a second embodiment and is a sectional view of the combustion apparatus 2 and the heating vessel 10.
In the second embodiment, the width of the lower portion 25a having a predetermined height (for example, 40 mm) from the lowermost end of the outer peripheral fin 25 is set to, for example, 6 mm, and is 3 times smaller than the width of the upper portion 25b (for example, 9 mm).
mm.

[Third Embodiment] FIG. 6 shows a third embodiment, and is a sectional view of the combustion apparatus 2 and the heating vessel 10.
In the first and second embodiments, the lower portion 2 of the outer peripheral fin 25
5a is removed from the upper part 25b, so that the outer fin 2
5 shows an example in which high-temperature oxidation due to overheating of the lower end outside is prevented. On the other hand, in the third embodiment, the outer peripheral fin 25
A restricting plate 30 (for example, made of stainless steel) for guiding the exhaust gas to the inside of the outer peripheral fins 25 is provided in the outer peripheral exhaust passage 28b immediately below the outer exhaust passage 28b to form a gap through which the exhaust gas passes only inside the outer peripheral exhaust passage 28b. Is formed so that the outside of the lower end of the outer peripheral fin 25 is not overheated by forming a blind spot where the flow does not directly hit.

Due to the positional relationship with the exhaust port 27 in the outer peripheral exhaust passage 28b, a small exhaust gap (corresponding to the exhaust area) by the restriction plate 30 is provided on the exhaust port 27 side.
On the side distant from 7, a large exhaust gap is provided by the restriction plate 30. For this reason, the amount of exhaust gas in the entire circumference of the outer peripheral exhaust passage 28b is made uniform, and local overheating of the outer peripheral fin 25 can be further prevented. In this embodiment, an example is shown in which an exhaust gap is provided between the limiting plate 30 and the outer peripheral wall surface 23b to guide the exhaust gas to the outer peripheral wall surface 23b side. Exhaust gas is supplied to the outer peripheral wall 23b at the position of the hole.
It may be provided so as to guide to the side. In addition, the passage resistance of the exhaust gas is adjusted according to the size and number of the holes, and the outer peripheral exhaust passage 2 is adjusted.
The exhaust gas amount in the entire circumference of 8b may be made uniform.

[Modification] In the above embodiment, the double-effect absorption refrigeration cycle 3 has been described as an example of the absorption refrigeration cycle. However, a single-effect absorption refrigeration cycle may be used. A triple effect or more multi-effect absorption refrigeration cycle may be used. In addition, when the middle liquid is injected into the low-temperature regenerator 16, an example is shown in which the medium is injected from above the low-temperature regenerator 16.
It may be injected from below.

Although the Bunsen type is shown as an example of the burner 11, an all-primary gas burner that burns an air-rich mixture of gas and combustion air may be used,
A premixed Bunsen gas burner that burns a gas-rich mixture of a gas and combustion air and supplies secondary air to a combustion unit may be used. As an example of the burner 11, an example in which a plurality of flattened bodies are provided and provided is shown.
Other burners such as a ceramic burner may be used. Although a combustion device that burns gas is shown as an example of the combustion device 2, a combustion device that burns with liquid fuel may be used.

Although an aqueous solution of lithium bromide has been described as an example of the absorbing liquid, other absorbing liquids such as an aqueous ammonia solution using ammonia as a refrigerant and water as an absorbent may be used. As an example of the heat medium, tap water is used and shared with the cooling water in the cooling water circuit. However, other heat medium such as antifreeze or oil different from the cooling water in the cooling water circuit may be used. Although the example in which the heat exchanger for condensation, the heat exchanger for evaporation, and the heat exchanger for absorption are provided in a coil shape is shown, the heat exchanger of another type such as a tube and fin or a stacked heat exchanger is used. Is also good.

In the above-described embodiment, an example in which the present invention is applied to the outer peripheral fin 25 provided on the outer peripheral wall surface 23b has been described. However, the inner peripheral fin is provided on the inner peripheral wall surface 23a, and the most upstream end of the inner peripheral fin is provided. May be provided at the upper end, or the restriction plate 30 may be provided upstream of the inner peripheral fin. In this case, the outer peripheral fin 25 may be provided with a missing portion,
It is not necessary to provide the restriction plate 30 on the upstream side.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a combustion device and a heating vessel (first example).
Example).

FIG. 2 is a schematic diagram of an air conditioner using an absorption refrigeration cycle (first embodiment).

FIG. 3 is a sectional view of a main part of an outer peripheral fin (first embodiment).

FIG. 4 is an enlarged view of a main part of an outer peripheral fin (first embodiment).

FIG. 5 is a sectional view of a combustion device and a heating vessel (second example).
Example).

FIG. 6 is a sectional view of a combustion device and a heating vessel (third view).
Example).

FIG. 7 is a cross-sectional view of a combustion device and a heating vessel (conventional example).

[Explanation of symbols]

 Reference Signs List 2 Combustion device 3 Absorption refrigeration cycle 10 Heating vessel 11 Burner 13 Combustion fan 15 High temperature regenerator 16 Low temperature regenerator 17 Condenser 18 Evaporator 19 Absorber 20 Solution pump 23 Annular cylindrical container part 23b Outer peripheral wall surface 25 Outer peripheral fin 25a Outer peripheral fin Lower part 27 exhaust port 28b outer peripheral exhaust passage 30 restriction plate

Claims (4)

[Claims] 1. A burner for burning fuel, a combustion device provided with a combustion fan for forcibly sending air for combustion to the burner, and a heating vessel heated by the combustion device and supplied with an absorbing liquid. A regenerator that evaporates a part of the absorbing liquid, a condenser that cools and liquefies the vaporized refrigerant generated by the regenerator, and cools the heat medium by evaporating the liquefied refrigerant liquefied by the condenser under low pressure. An evaporator, an absorber that absorbs the vaporized refrigerant evaporated by the evaporator into an absorbent, an absorption refrigeration cycle including a solution pump that pumps the absorbed liquid that has absorbed the vaporized refrigerant in the evaporator to the regenerator, In the absorption type cooling device provided, the heating container covers the burner from above and presents a substantially U-shaped container shape having an annular tubular container portion, and the combustion device is generated by the burner. An exhaust passage for flowing gas gas along a wall surface of the annular cylindrical container portion; a fin for efficiently transmitting heat of exhaust gas to the annular cylindrical container portion on a wall surface of the annular cylindrical container portion; An uppermost end of the fin in the exhaust passage is missing a portion farther from the wall surface. 2. The absorption cooling device according to claim 1, wherein the most upstream end portion of the fin is cut obliquely so that a chipped width decreases toward a downstream side. Absorption cooling device. 3. A burner for burning fuel, a combustion device provided with a combustion fan for forcibly sending air for combustion to the burner, and a heating vessel heated by the combustion device and supplied with an absorbing liquid. A regenerator that evaporates a part of the absorbing liquid, a condenser that cools and liquefies the vaporized refrigerant generated by the regenerator, and cools the heat medium by evaporating the liquefied refrigerant liquefied by the condenser under low pressure. An evaporator, an absorber that absorbs the vaporized refrigerant evaporated by the evaporator into an absorbent, an absorption refrigeration cycle including a solution pump that pumps the absorbed liquid that has absorbed the vaporized refrigerant in the evaporator to the regenerator, In the absorption cooling device provided, the heating container covers the burner from above and presents a substantially U-shaped container shape having an annular tubular container portion, and the combustion device is generated by the burner. An exhaust passage for flowing gas gas along a wall surface of the annular cylindrical container portion; a fin for efficiently transmitting heat of exhaust gas to the annular cylindrical container portion on a wall surface of the annular cylindrical container portion; An absorption-type cooling device, wherein the exhaust passage includes a restriction plate on an upstream side of the fin to guide exhaust gas to a wall surface side of the annular cylindrical container portion. 4. The absorption cooling device according to claim 3, wherein the exhaust passage has an exhaust port for collecting exhaust gas and discharging the exhaust gas to the outside, and the restricting plate is provided for exhaust gas on a side close to the exhaust port. An absorption type cooling apparatus characterized in that an exhaust area through which the exhaust gas passes is reduced and an exhaust area through which exhaust gas farther from the exhaust port passes is increased.