EP4230947A1

EP4230947A1 - Heat exchange system, and practical apparatus comprising heat exchange system

Info

Publication number: EP4230947A1
Application number: EP21882408.4A
Authority: EP
Inventors: Taiki Umemoto; Satoshi Ohshiro; Tomoko Tani
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2020-10-19
Filing date: 2021-07-30
Publication date: 2023-08-23
Also published as: CN116134285A; TW202217217A; EP4230947A4; WO2022085267A1

Abstract

Heat exchange system (2) according to a first exemplary embodiment of the present disclosure includes heat exchanger (3) and supply member (4). Here, heat exchanger (3) has a plurality of fins (5) in contact with air containing moisture, and cools the air by exchanging heat via fins (5) between a refrigerant flowing inside and the air. Furthermore, supply member (4) supplies an additive for reducing a contact angle with respect to fins (5) to the moisture adhering to fins (5) by cooling of heat exchanger (3).

Description

TECHNICAL FIELD

The present disclosure relates to a heat exchange system and an application device including the heat exchange system, and particularly relates to a technology for improving heat exchange efficiency of the heat exchange system.

BACKGROUND ART

A heat exchange system mounted on an air conditioning device or the like includes, for example, a heat exchanger having a plurality of fins, and exchanges heat between air and a heat medium circulating inside through the plurality of fins. When the fins are cooled by heat exchange at the time of driving the heat exchange system, the air comes into contact with the fins, so that moisture in the air may aggregate and adhere to the fins. When moisture adheres to the fins, the heat exchange efficiency of the heat exchanger decreases due to the influence of specific heat, thermal conductivity, latent heat, sensible heat, or the like of the moisture. Furthermore, when moisture adheres to the plurality of fins, a gap between the fins is closed by the moisture. As a result, circulation of air in the heat exchanger is hindered, and heat exchange efficiency is reduced.
Therefore, for example, PTL 1 discloses a method in which a hydrophilic membrane containing a hydrophilic resin and a silicone resin is formed on a surface of a fin of a heat exchanger, moisture adhering to the fin is quickly discharged, and antifouling properties are imparted to the fin.

Citation List

Patent Literature

PTL 1: Unexamined Japanese Patent Publication No. 2014-29248

SUMMARY OF THE INVENTION

However, in the method of PTL 1, the hydrophilicity of the hydrophilic membrane tends to decrease due to the oil repellency of the silicone resin. Furthermore, in this method, it is difficult to sufficiently obtain antifouling properties, dirt adheres to the fin, and the hydrophilicity of the hydrophilic membrane decreases. As a result, in the method of PTL 1, the heat exchange efficiency of the heat exchanger decreases.
Therefore, an object of the present disclosure is to provide a heat exchange system capable of obtaining excellent heat exchange efficiency over a relatively long period from an initial stage of driving even when moisture adheres to fins of a heat exchanger during driving, and an application device including the heat exchange system.
A heat exchange system according to one aspect of the present disclosure includes a heat exchanger and a supply member. The heat exchanger includes a plurality of fins in contact with air containing moisture, and cools the air by exchanging heat via the fins between a refrigerant flowing inside and the air. The supply member supplies an additive that reduces a contact angle with respect to the fins to the moisture attached to the fins by cooling of the heat exchanger.
Furthermore, an application device according to one aspect of the present disclosure includes the heat exchange system described above.
The heat exchange system according to one aspect of the present disclosure and the application device according to one aspect of the present disclosure can obtain excellent heat exchange efficiency over a relatively long period from the initial stage of driving even when moisture adheres to the fins of the heat exchanger during driving.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view illustrating a configuration of an indoor unit of an application device according to a first exemplary embodiment.
Fig. 2 is an enlarged schematic view illustrating a state in which an additive is supplied from a supply member in Fig. 1 to moisture adhering to fins.
Fig. 3 is an enlarged view illustrating an internal structure of the supply member in Fig. 1.
Fig. 4 is a schematic diagram illustrating a schematic configuration of an application device according to a second exemplary embodiment.
Fig. 5A is a diagram illustrating a state in which moisture adheres to a fin of a heat exchanger in a conventional freezing device.
Fig. 5B is a diagram illustrating a state in which water adhering to the fin of the heat exchanger in the conventional freezing device is dissolved and a state in which water remains in the fin.
Fig. 5C is a diagram illustrating a state in which frost accumulates on the fin of the heat exchanger in the conventional freezing device.
Fig. 6A is a diagram illustrating a state in which moisture adheres to a fin of a heat exchanger in the application device of the second exemplary embodiment.
Fig. 6B is a diagram illustrating a state in which water slides down from the fin of the heat exchanger in the application device of the second exemplary embodiment.
Fig. 6C is a diagram illustrating the fin of the defrosted heat exchanger in the application device of the second exemplary embodiment.
Fig. 7 is a graph illustrating a relationship between an operation cycle time and a heating capability of each application device of Example 4 and Comparative Example 4 in a test result of Test 5.
Fig. 8 is a graph illustrating a relationship between the number of defrosting times and a defrosting time of each application device of Example 5 and Comparative Examples 6 and 7 in a test result of Test 6.
Fig. 9 is a graph illustrating a relationship between the number of defrosting times and a cooling time of each application device of Example 5 and Comparative Examples 6 and 7 in the test result of Test 6.
Fig. 10 is a diagram illustrating a photograph of a heat exchanger of Example 5 before defrosting.
Fig. 11 is a diagram illustrating a photograph of the heat exchanger of Example 5 after defrosting.
Fig. 12 is a diagram illustrating a photograph of a heat exchanger of Comparative Example 6 before defrosting.
Fig. 13 is a diagram illustrating a photograph of the heat exchanger of Comparative Example 6 after defrosting.
Fig. 14 is a diagram illustrating a photograph of a heat exchanger of Comparative Example 7 before defrosting.
Fig. 15 is a diagram illustrating a photograph of the heat exchanger of Comparative Example 7 after defrosting.
Fig. 16 is a graph illustrating a relationship between an operating time and a freezing chamber temperature of each application device of Example 5 and Comparative Example 6 in the test result of Test 6.
Fig. 17 is a graph illustrating a relationship between the number of defrosting times and the freezing chamber temperature in each application device of Example 5 and Comparative Examples 6 and 7 in the test result of Test 6.

DESCRIPTION OF EMBODIMENT

A heat exchange system according to one aspect of the present disclosure includes a heat exchanger and a supply member. The heat exchanger includes a plurality of fins in contact with air containing moisture, and cools the air by exchanging heat via the fins between a refrigerant flowing inside and the air. The supply member supplies an additive that reduces a contact angle with respect to the fins to the moisture attached to the fins by cooling of the heat exchanger.
According to the above configuration, in the heat exchange system according to one aspect of the present disclosure, when moisture adheres to the fins of the heat exchanger at the time of cooling the air by heat exchange with the refrigerant, the contact angle of the moisture with respect to the fins is reduced by the additive supplied from the supply member. This improves the wettability of a surface of the fins, and the heat exchange system according to one aspect of the present disclosure can thin a water membrane formed on the surface of the fins. Furthermore, since a surface tension of the moisture decreases, the heat exchange system according to one aspect of the present disclosure can easily discharge the moisture from the surface of the fins. As a result, in the heat exchange system according to one aspect of the present disclosure, it is possible to prevent a decrease in heat exchange efficiency due to the moisture attached to the fins, or a decrease in heat exchange efficiency of the heat exchange system because of inhibition of air flow in the heat exchanger due to the moisture attached to the surface of the fins. Furthermore, since the thin water membrane is formed on the surface of the fins, even when impurities in the air adhere to the fins, the impurities are quickly discharged together with the water membrane, and the heat exchange system according to one aspect of the present disclosure can maintain the fins in a clean state.
Furthermore, these effects are sustained by supplying the additive to the moisture adhering to the fins by the supply member. Moreover, in the heat exchange system according to one aspect of the present disclosure, since the additive can be supplied to the moisture adhering to the fins by the supply member, the trouble of supplying the additive can be omitted. Therefore, the heat exchange system according to one aspect of the present disclosure can obtain excellent heat exchange efficiency over a relatively long period of time even when moisture or dirt adheres to the fins of the heat exchanger during driving.
Furthermore, in the heat exchange system according to one aspect of the present disclosure, the additive may be supplied from the supply member to the moisture adhering to the fins by free fall. As a result, the heat exchange system according to one aspect of the present disclosure can automatically and efficiently add the additive from the supply member to the fins using gravity, and can simplify a structure of the heat exchange system according to one aspect of the present disclosure.
Furthermore, in the heat exchange system according to one aspect of the present disclosure, the supply member may be disposed so as to be in contact with the fins. As a result, the heat exchange system according to one aspect of the present disclosure can easily supply the additive from the supply member to the moisture adhering to the fins.
Furthermore, in the heat exchange system according to one aspect of the present disclosure, the plurality of fins may extend in a vertical direction and be arranged side by side in an intersecting direction intersecting the vertical direction, and the supply member may have an elongated shape in the intersecting direction and be disposed to be in contact with end surfaces of the plurality of fins. As a result, the heat exchange system according to one aspect of the present disclosure can easily diffuse and supply the additive from the supply member along the surface extending in the vertical direction of each fin with respect to the moisture attached to the plurality of fins.
Furthermore, in the heat exchange system according to one aspect of the present disclosure, the supply member may be detachably disposed with respect to the heat exchanger. As a result, the heat exchange system according to one aspect of the present disclosure can improve maintainability of the heat exchange system according to one aspect of the present disclosure, and the supply member can be easily replaced as necessary. Therefore, the heat exchange system according to one aspect of the present disclosure can maintain stable heat exchange efficiency for a relatively long period of time.
Furthermore, in the heat exchange system according to one aspect of the present disclosure, the supply member may include a plurality of carriers that carry the additive, and a support that supports the plurality of carriers in a state where the plurality of carriers is dispersed so that the additive can be released from the carriers to the outside of the supply member.
According to the above configuration, the heat exchange system according to one aspect of the present disclosure can easily supply the additive to a wide range of the moisture adhering to the fins from each carrier by carrying the additive by the plurality of dispersed carriers. Furthermore, in the heat exchange system according to one aspect of the present disclosure, the support supports the plurality of carriers so that the additive can be released from the plurality of carriers to the outside of the supply member, whereby the additive can be stably supplied from the supply member to the fins while the carriers are supported.
Furthermore, in the heat exchange system according to one aspect of the present disclosure, the carriers may be porous granules. As a result, the heat exchange system according to one aspect of the present disclosure can hold an abundant additive in holes of the carriers and slowly release the additive from the supply member to the fins. Therefore, the heat exchange system according to one aspect of the present disclosure can supply the additive to the moisture adhering to the fins over a relatively long period from the initial stage of driving of the heat exchange system according to one aspect of the present disclosure.
Furthermore, in the heat exchange system according to one aspect of the present disclosure, the additive may be a surfactant. As a result, the heat exchange system according to one aspect of the present disclosure can easily favorably reduce the contact angle of the moisture attached to the fins. Furthermore, the heat exchange system according to one aspect of the present disclosure can improve the degree of freedom in designing the heat exchange system according to one aspect of the present disclosure by using, for example, an existing surfactant as the additive.
Furthermore, in the heat exchange system according to one aspect of the present disclosure, the additive may be dissolved, dispersed, or diffused with respect to the moisture attached to the fins. As a result, the heat exchange system according to one aspect of the present disclosure can quickly spread the additive from the supply member to the moisture adhering to the fins.
An application device according to one aspect of the present disclosure includes any of the heat exchange systems described above. The application device according to one aspect of the present disclosure can obtain excellent heat exchange efficiency over a relatively long period of time even when moisture or dirt adheres to the fins of the heat exchanger during driving.
Furthermore, the application device according to one aspect of the present disclosure may be an air conditioning device including an indoor unit, and the heat exchange system may be mounted on the indoor unit.
Furthermore, the application device according to one aspect of the present disclosure may be an air conditioning device including an outdoor unit and may include a defrosting mechanism that removes frost adhering to the heat exchanger, and the heat exchange system may be mounted on the outdoor unit.
Furthermore, the application device according to one aspect of the present disclosure may be a freezing device including a defrosting mechanism that removes frost adhering to the heat exchanger, and refrigerating or freezing an object.
Hereinafter, each exemplary embodiment will be described with reference to the drawings.

(First exemplary embodiment)

[Heat exchange system and application device]

Fig. 1 is a perspective view illustrating a configuration of indoor unit 10 of application device 1 according to a first exemplary embodiment. Fig. 2 is an enlarged schematic view illustrating a state in which an additive is supplied from supply member 4 in Fig. 1 to moisture adhering to fins 5. As an example, application device 1 illustrated in Fig. 1 is an air conditioning device including indoor unit 10 and an outdoor unit (not illustrated). This air conditioning device functions as a cooling device in the present exemplary embodiment. Application device 1 includes heat exchange system 2. Heat exchange system 2 is mounted on indoor unit 10.
In application device 1, a refrigerant circulates between indoor unit 10 and the outdoor unit. Heat exchange system 2 exchanges heat between indoor air and a refrigerant. Heat exchange system 2 includes heat exchanger (evaporator) 3 that has a plurality of fins 5 in contact with air containing moisture and through which the refrigerant flows, and a plurality of supply members 4 that supply an additive for reducing a contact angle with respect to fins 5 to the moisture attached to fins 5.
When the air conditioning device is driven as a cooling device, heat exchanger 3 cools indoor air by exchanging heat via fins 5 between the refrigerant flowing inside and the indoor air. As an example, the plurality of fins 5 extend in a vertical direction and are arranged side by side at intervals in an intersecting direction (here, a horizontal direction) intersecting the vertical direction. As an example, fins 5 contain a metal material (aluminum or the like) having excellent thermal conductivity, but the material of fins 5 is not limited thereto. The plurality of fins 5 are in contact with flow pipe 6 through which the refrigerant of heat exchanger 3 flows.
Each of supply members 4 supplies an additive for reducing a contact angle with respect to fins 5 to the moisture adhering to fins 5 when the indoor air is cooled. Accordingly, as described later, supply member 4 can thin a water membrane formed on a surface of fins 5. In the present exemplary embodiment, supply member 4 is disposed so as to be in contact with fins 5, and the additive of supply member 4 is supplied from supply member 4 to the moisture adhering to fins 5 by free fall. Supply member 4 gradually releases the additive so as to continuously supply the additive to the moisture adhering to fins 5 for a predetermined period (for example, about several years). Supply member 4 comes into contact with the moisture to release the additive to the outside while dispersing the additive in water.
As illustrated in Figs. 1 and 2, as an example, supply member 4 is elongated in the intersecting direction, and is disposed so as to be in contact with end surfaces of the plurality of fins 5. Supply member 4 is formed in a strip shape, and is disposed such that the longitudinal direction is along an arrangement direction of the plurality of fins 5. Supply member 4 is detachably disposed with respect to heat exchanger 3. That is, supply member 4 is exchangeable with respect to heat exchanger 3 at a predetermined timing.
Heat exchange system 2 of the present exemplary embodiment includes the plurality of supply members 4 arranged apart from each other. One of supply members 4 is in contact with the end surface of each of fins 5 while extending in a thickness direction of the plurality of fins 5 of heat exchanger 3. As illustrated in Fig. 1, heat exchanger 3 includes, as an example, a plurality of blocks 3a to 3c disposed to be bent from each other in a circumferential direction of columnar fan 11 of indoor unit 10. The plurality of supply members 4 are disposed so as to overlap with blocks 3a to 3c. As a result, each of supply members 4 supplies the additive to the moisture adhered to the plurality of fins 5 of each of blocks 3a to 3c. In the present exemplary embodiment, at least one supply member 4 is disposed between filter 7 included in indoor unit 10 and heat exchanger 3.
Fig. 3 is an enlarged view illustrating an internal structure of supply member 4 in Fig. 1. As illustrated in Fig. 3, supply member 4 includes a plurality of carriers 40 that carry the additive, and a support 41 that supports the plurality of carriers 40 in a state where the plurality of carriers 40 are dispersed so that the additive can be released from the carriers 40 to the outside of supply member 4.
Carriers 40 of the present exemplary embodiment are a porous granular material. An outer diameter of the granular material can be appropriately set, and for example, can be set to a value of several µm. As an example, the granular material can have a pore volume set to a value of several mL/g, a pore diameter set to a value of a dozen or so nanometers, and a specific surface area set to a value of several hundred m²/g. The particle size, specific surface area, and pore size of the granular material are set to values suitable for sustained release of the additive required for supply member 4, for example. By constituting carriers 40 with the porous granular material, for example, an abundant additive can be carried inside carriers 40. Carriers 40 of the present exemplary embodiment contains an inorganic component. As an example, carriers 40 are made of porous glass containing glass such as amorphous silica. As a material of carriers 40, at least one of porous glass, activated carbon, zeolite, and porous concrete can be exemplified.
Support 41 of the present exemplary embodiment contains a water-insoluble component. The water-insoluble component is, for example, a water-insoluble resin. Examples of the water-insoluble resin include at least one of polyethylene, polypropylene, polyamide, polyethylene terephthalate, polybutylene terephthalate, and acrylic-modified polyethylene (for example, "Acryft" manufactured by Sumitomo Chemical Co., Ltd.).
In supply member 4, a gap between the plurality of carriers 40 is filled with support 41. As a result, the plurality of carriers 40 are supported by support 41 in a state of being in contact with or separated from each other. When supply member 4 comes into contact with water, for example, an additive is supplied from carriers 40 located on a surface layer of supply member 4 and elutes in water. As a result, the concentration of the additive in carriers 40 on the surface layer decreases. Thereafter, the additive moves from carriers 40 located inside supply member 4 toward carriers 40 located on the surface layer of supply member 4, and the concentration of the additive in carriers 40 on the surface layer increases. The additive of carriers 40 on the surface layer is eluted in water. By this repetition, the additive is supplied from supply member 4 to the external water.
This additive can be appropriately selected as long as it reduces a contact angle with respect to fins 5 with respect to the moisture attached to fins 5. Examples of the additive include a surfactant. The surfactant herein refers to a compound having a hydrophilic group and a hydrophobic group in a molecular structure. Examples of the surfactant include fatty acid salts, N-acylsarcosine salts, N-acylglutamate salts, alkylbenzene sulfonate salts, malic acid amides, alkane sulfonate salts, alkyl sulfates, polyoxyethylene alkyl ether sulfates, α-olefin sulfonate salts, N-acyl-N-methyltaurate salts, N-sulfofatty acid esters, and alkyl phosphates in the case of an anionic surfactant. Furthermore, examples of the cationic surfactant include an alkyltrimethylammonium salt, an alkylbenzalkonium chloride, a fatty acid amidopropyl cation, a fatty acid amidobutylguanidine, and a dialkyldimethylammonium salt. Furthermore, examples of the amphoteric surfactant include alkyldimethylacetate betaine, fatty acid amidopropyl betaine, alkyldimethylhydroxysulfobetaine, amino acid salt, alkylamine oxide, and alkylimidazolinium betaine. Furthermore, examples of the nonionic surfactant include oxyalkylene alkyl ether-based surfactants such as fatty acid glycerin ester, fatty acid sorbitan ester, fatty acid sucrose ester, alkyl polyglucoside, polyoxyethylene propylene alkyl ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, and polyoxyethylene polyoxypropylene glycol. The surfactant is not limited thereto, and can be suitably selected according to the object to be used and the environment.
As an example, supply member 4 contains 20 wt% or more and 50 wt% or less of support 41, 10 wt% or more and 30 wt% or less of carriers 40 (porous granules before carrying the additive), and a composition formed from the remainder. The additive is contained in the remainder. The composition ratio of supply member 4 is not limited thereto.
As illustrated in Fig. 2, by using the surfactant as the additive, when the additive is supplied to the moisture adhering to the plurality of fins 5, the contact angle can be favorably reduced, and the additive can be diffused over a wide area of each fin 5. Examples of the additive include a water-soluble organic solvent in addition to a surfactant. Examples of the organic solvent include alcohols, ketones, esters, and ethers. Among these, for example, a lower alcohol is suitable. Examples of the lower alcohol include ethanol, propanol, isopropyl alcohol, and butanol.
The additive of the present exemplary embodiment dissolves, disperses, or diffuses with respect to the moisture attached to fins 5. This makes it possible to quickly spread the additive from supply member 4 to the moisture adhering to fins 5 even in the direction intersecting the vertical direction, for example.
Next, a method of manufacturing supply member 4 will be exemplified. As an example, first, the carriers 40 (porous granular material before carrying the additive), support 41, and the additive are heated and kneaded to form a strand. Next, the strand is cut into a predetermined size, and then the cut piece is injection molded to obtain supply member 4 having a desired shape. When supply member 4 is manufactured by injection molding, the shape of supply member 4 can be easily set in accordance with, for example, the shape of heat exchanger 3. As described above, when supply member 4 is manufactured by heating and kneading and injection molding the material, the material of carriers 40 preferably has strength that can withstand kneading and heat resistance in a temperature range during injection molding. Furthermore, as materials of support 41 and the additive, those having heat resistance in a temperature range during the injection molding are suitable.
The shape of supply member 4 is not limited to the elongated shape, and may be, for example, a spherical shape such as an elliptical sphere or a rectangular parallelepiped. When a single or small amount of supply member 4 is disposed in indoor unit 10, for example, by disposing cylindrical supply member 4 on a top of heat exchanger 3 such that the longitudinal direction is along the arrangement direction of the plurality of fins 5, the additive can be efficiently diffused over a wide area of each fin 5.
Supply member 4 may contain other components. Examples of the components include, but are not limited to, at least one of surfactants, esters, salts, defoamers, viscosity modifiers, fragrances, colorants, pH adjusters, antioxidants, and inorganic substances such as talc and silica different from the above-described additives. Furthermore, the number of supply members 4 included in heat exchange system 2 is not limited.
When application device 1 is driven as a cooling device, for example, a low-temperature refrigerant supplied from a compressor included in the outdoor unit flows through heat exchanger 3 of indoor unit 10. The indoor air comes into contact with the plurality of fins 5 of heat exchanger 3. As a result, the indoor air is cooled by heat exchange with the refrigerant flowing inside heat exchanger 3 via the plurality of fins 5. The cooled air is discharged from indoor unit 10 into the room. Since the indoor air contains moisture, moisture adheres to fins 5 when fins 5 cooled by the refrigerant come into contact with the indoor air. The refrigerant used for the heat exchange is sent from indoor unit 10 to the outdoor unit. The refrigerant is condensed by heat exchange with the outside air by the condenser of the outdoor unit, compressed by the compressor, and supplied to indoor unit 10 again.
Here, the moisture adhering to the fins in the conventional heat exchange system is, for example, aggregated into water droplets. When waterdrops adhere to the fins in the conventional heat exchange system, the heat exchange efficiency of the heat exchanger in the conventional heat exchange system decreases due to the influence of specific heat, thermal conductivity, latent heat, sensible heat, or the like of water. Furthermore, when a waterdrop adheres to the plurality of fins in the conventional heat exchange system, a gap between the fins is closed by the waterdrop, circulation of air in the heat exchanger in the conventional heat exchange system is hindered, and heat exchange efficiency is reduced. Furthermore, impurities in the air adhere to the fins in the conventional heat exchange system, and the fins are contaminated, so that the heat exchange efficiency is lowered.
On the other hand, the heat exchange system 2 of the present exemplary embodiment includes heat exchanger 3 and supply member 4. Heat exchanger 3 has the plurality of fins 5 in contact with air containing moisture, and cools the air by exchanging heat via fins 5 between the refrigerant flowing inside and the air. Supply member 4 supplies an additive for reducing the contact angle with respect to fins 5 to the moisture adhering to fins 5 by the cooling of heat exchanger 3.
With this configuration, in heat exchange system 2 of the present exemplary embodiment, when the moisture adheres to fins 5 of heat exchanger 3 at the time of cooling the air by heat exchange with the refrigerant, the contact angle of the moisture with respect to fins 5 is reduced by the additive supplied from supply member 4. As a result, the wettability of the surface of fins 5 is improved, and the water membrane formed on the surface of fins 5 can be thinned. Furthermore, since the surface tension of the moisture decreases (in other words, a surface energy of the moisture decreases), the moisture can be easily discharged from the surface of fins 5. As a result, it is possible to prevent a decrease in heat exchange efficiency of heat exchange system 2 due to the moisture adhering to fins 5, and a decrease in heat exchange efficiency because of inhibition of air flow in heat exchanger 3 due to the moisture adhering to fins 5. Furthermore, since the thin water membrane is formed on fins 5, even when impurities in the air adhere to fins 5, the impurities are quickly discharged together with the water membrane, and fins 5 can be maintained in a clean state.
Furthermore, these effects are sustained by supplying the additive to the moisture adhering to fins 5 by supply member 4. As described above, the additive is supplied from supply member 4 to the moisture adhering to fins 5 over a predetermined period (for example, about several years). Furthermore, heat exchange system 2 can supply the additive to the moisture adhering to fins 5 by supply member 4. Therefore, heat exchange system 2 can omit time and effort for supplying the additive. As described above, supply member 4 is exchangeable with respect to heat exchanger 3. Therefore, even when moisture or dirt adheres to fins 5 of heat exchanger 3 during driving, heat exchange system 2 can obtain excellent heat exchange efficiency over a relatively long period (at least several years, and a longer period of time when supply member 4 is replaced) from the initial stage of driving of heat exchange system 2.
In heat exchange system 2 of the present exemplary embodiment, the additive is supplied from supply member 4 to the moisture adhering to fins 5 by free fall. As a result, in heat exchange system 2 of the present exemplary embodiment, the additive can be automatically and efficiently added from supply member 4 to fins 5 using gravity, and a structure of heat exchange system 2 can be simplified.
Furthermore, in heat exchange system 2 of the present exemplary embodiment, supply member 4 is disposed so as to be in contact with fins 5. As a result, heat exchange system 2 of the present exemplary embodiment can easily supply the additive from supply member 4 to the moisture adhering to fins 5.
Furthermore, in heat exchange system 2 of the present exemplary embodiment, the plurality of fins 5 extend in the vertical direction and are arranged so as to be aligned in the intersecting direction intersecting the vertical direction, and supply member 4 has an elongated shape in the intersecting direction and is disposed so as to be in contact with the end surfaces of the plurality of fins 5. As a result, heat exchange system 2 of the present exemplary embodiment can easily diffuse and supply the additive from supply member 4 along the surface extending in the vertical direction of each fin 5 with respect to the moisture attached to the plurality of fins 5.
Furthermore, in heat exchange system 2 of the present exemplary embodiment, supply member 4 is detachably disposed with respect to heat exchanger 3. As a result, in heat exchange system 2 of the present exemplary embodiment, maintainability of heat exchange system 2 can be improved, and supply member 4 can be easily replaced as necessary. Therefore, heat exchange system 2 of the present exemplary embodiment can maintain stable heat exchange efficiency for a relatively long period of time.
Furthermore, in heat exchange system 2 of the present exemplary embodiment, supply member 4 includes, as an example, a plurality of carriers 40 that carry the additive, and support 41 that supports the plurality of carriers 40 in a state where the plurality of carriers 40 are dispersed so that the additive can be released from carriers 40 to the outside of supply member 4.
According to the above configuration, in heat exchange system 2 of the present exemplary embodiment, the additive is carried by the plurality of dispersed carriers 40, so that the additive can be easily supplied from each carrier 40 to a wide range of the moisture adhering to fins 5. Furthermore, in heat exchange system 2 of the present exemplary embodiment, support 41 supports the plurality of carriers 40 so that the additive can be released from each of carriers 40 to the outside of supply member 4, whereby the additive can be stably supplied from supply member 4 to fins 5 while carriers 40 are supported.
In heat exchange system 2 of the present exemplary embodiment, carriers 40 are porous granular material. As a result, heat exchange system 2 of the present exemplary embodiment can hold an abundant additive in the holes of carriers 40, slowly release the additive from supply member 4 to fins 5, and supply the additive to the moisture adhering to fins 5 for a relatively long period from the initial stage of driving of heat exchange system 2.
Furthermore, in heat exchange system 2 of the present exemplary embodiment, the additive is a surfactant. As a result, heat exchange system 2 of the present exemplary embodiment can easily favorably reduce the contact angle of the moisture attached to fins 5. Furthermore, heat exchange system 2 of the present exemplary embodiment can improve the degree of freedom in designing heat exchange system 2 by using, for example, an existing surfactant as the additive.
Furthermore, as illustrated in Fig. 1, in heat exchange system 2 of the present exemplary embodiment, the additive flowing through the surfaces of fins 5 is received by drain pans 8 and 9 of indoor unit 10. As a result, in heat exchange system 2 of the present exemplary embodiment, for example, the additive is favorably prevented from adhering to an unnecessary part of application device 1.
Note that, when application device 1 including heat exchange system 2 is an air conditioning device, the air conditioning device may be a heating device or may also serve as a heating device. When the air conditioning device is driven as a heating device, heat exchange system 2 may be mounted on an outdoor unit. Furthermore, the air conditioning device is not limited to the configuration including indoor unit 10 and the outdoor unit, and may be, for example, a spot air conditioner or a car air conditioner. Furthermore, application device 1 is not limited to the air conditioning device, and may be, for example, a refrigeration device, a freezing device, a drying device, or the like. Heat exchange system 2 may be used for cooling air by heat exchange between the refrigerant flowing inside heat exchanger 3 and air via fins 5 of heat exchanger 3. Hereinafter, a second exemplary embodiment will be described focusing on differences from the first exemplary embodiment.

(Second exemplary embodiment)

Fig. 4 is a schematic diagram illustrating a schematic configuration of application device 101 according to a second exemplary embodiment. Figs. 5A to 5C are diagrams schematically illustrating a fin of a heat exchanger and surroundings of the fin before and after defrosting (defrosting) in a conventional freezing device. Figs. 6A to 6C are diagrams schematically illustrating fin 5 of heat exchanger 3 and the surroundings of the fin before and after defrosting in application device 101 according to the second exemplary embodiment. Application device 101 illustrated in Fig. 4 is a freezing device that refrigerates or freezes an object. Application device 101 includes refrigerating chamber 102, freezing chamber 103, vegetable chamber 104, heat exchanger 3, and defrosting mechanism 105 that removes frost adhering to heat exchanger 3. A defrosting method of defrosting mechanism 105 is, for example, a heater method. The defrosting method of defrosting mechanism 105 is not limited thereto, and may be any of other known methods such as a hot gas method, a water spraying method, and an off-cycle method.
As illustrated in Figs. 5A to 5C, when the fin of the heat exchanger in the conventional freezing device is cooled to below the freezing point, passes through a supercooled state, and the supercooled state is released, moisture (dew condensation water) adhering to the fin of the conventional freezing device is frozen. This causes frost to adhere to the fin of the conventional freezing device (Fig. 5A). When the adhesion of the frost to the fin of the conventional freezing device is repeated, the frost accumulates. The accumulation of the frost reduces heat exchange efficiency. Therefore, by operating the defrosting mechanism of the conventional freezing device in this state, the frost adhering to the fin of the conventional freezing device is melted and removed. However, in a normal defrosting operation of the defrosting mechanism in the conventional freezing device, it is difficult to completely defrost the fin, and some moisture (frost or waterdrops) remains in the fin of the conventional freezing device (Fig. 5B). When a re-cooling operation in which the freezing device re-cools the inside thereof to a set temperature is performed after the defrosting operation in a state where the moisture remains in the fin of the conventional freezing device, the moisture is re-frozen and remains as ice on the surface of the fin of the conventional freezing device. The frost further adheres on the basis of this residue, so that the frost cumulatively accumulates in the conventional freezing device (Fig. 5C). As a result, normal heat exchange of the heat exchanger in the conventional freezing device is hindered, and a heat exchange rate of the conventional freezing device decreases.
As illustrated in Figs. 6A to 6C, on the other hand, in application device 101 of the second exemplary embodiment, the defrosting operation of defrosting mechanism 105 melts the frost and generates a plurality of waterdrops in fin 5 (Fig. 6A). In application device 101, the moisture of the waterdrops attached to fin 5 is modified by the additive supplied by supply member 4. The plurality of adjacent waterdrops are bonded by hydrophilicity to each other, and slide down on a surface of fin 5 by its own weight. As a result, in application device 101, the frost is removed from fin 5 (Fig. 6B). As a result, in application device 101, most of the moisture is discharged from fin 5. As a result, in application device 101, even if the defrosting operation and the re-cooling operation are repeatedly performed, cumulative accumulation of frost on the surface of fin 5 is prevented (Fig. 6C). Therefore, in application device 101, an excellent heat exchange rate can be obtained over a long period of time. Therefore, application device 1 can improve power saving as a whole. Furthermore, since the cumulative accumulation of frost on the surface of fin 5 is prevented, application device 101 can reduce a defrosting amount to be defrosted in one defrosting operation. As a result, the defrosting time is shortened in application device 101. Furthermore, in application device 101, since an amount of heat required for defrosting is suppressed, an increase in the internal temperature during the defrosting operation is also relatively suppressed. Therefore, application device 101 can also suppress a temperature rise of an object in a refrigerator or freezer. Furthermore, since application device 101 can reduce a frequency of the defrosting operation, the above-described effect can be further enhanced.
Next, a modification example of the exemplary embodiment will be described. The application device according to the present modification example is an air conditioning device including an outdoor unit. This application device is driven as a heating device. Examples of the application device driven as the heating device include, but are not limited to, a heat pump water heater, a heat pump hot water heating device, a hot water heating device using hot water supply, and a heat pump heating device dedicated to an electric vehicle (EV). The application device according to this modification example includes, for example, defrosting mechanism 105 that removes frost adhering to heat exchanger 3. Heat exchange system 2 including heat exchanger 3 of the application device according to the modification example is mounted on the outdoor unit. Even in the application device of the present modification example having such a configuration, the same effects as those of application device 101 can be obtained. Note that the frost adhering to heat exchanger 3 in the outdoor unit may be derived from snow.

(Confirmation test)

[Test 1]

Test 1 was performed using an application device according to Example 1 of the present disclosure and an application device of Comparative Example 1. The application device of Example 1 basically has the same configuration as application device 1 that is the air conditioning device according to the first exemplary embodiment, and includes a commercially available dehumidifier ("AR-30HC" manufactured by SUGGEST) and supply member 4. The commercially available dehumidifier has a configuration in which heat exchange system 2 and a condenser are disposed in the same housing, and air that has passed through heat exchanger 3 (evaporator) further passes through the condenser and is discharged to the outside of the housing.
In the application device of Example 1, three strip-shaped supply members 4 whose longitudinal lengths extend in the horizontal direction are disposed apart from each other so as to be in contact with the end surface of each fin 5 above the plurality of fins 5 extending in the vertical direction and arranged in the intersecting direction intersecting the vertical direction. Furthermore, in the application device of Example 1, dumbbell-shaped supply member 4 in which a width dimension of both end parts is larger than a width dimension of the central part in the longitudinal direction in plan view is used.
Furthermore, the application device of Comparative Example 1 is similar to the application device of Example 1 except that a dummy plate body is used instead of supply member 4. In Test 1, the application device of Example 1 and the application device of Comparative Example 1 were driven under the conditions of a room temperature of 27°C and a relative humidity (RH) of 45%, and a performance difference between the application device of Example 1 and the application device of Comparative Example 1 was confirmed up to 100 minutes before the start of driving.
As a result, in the application device of Example 1, it was confirmed that a temperature difference between temperature T1 of air in the vicinity of an introduction port for introducing the air into heat exchanger 3 and temperature T2 of air immediately after passing through heat exchanger 3 was large as compared with the application device of Comparative Example 1. That is, in the application device of Example 1, it was confirmed that heat exchanger 3 appropriately exchanges heat between the air and the refrigerant.

[Test 2]

Test 2 was performed using an application device according to Example 2 of the present disclosure and an application device of Comparative Example 2. The application device of Example 2 basically has the same configuration as application device 1 which is the air conditioning device according to the first exemplary embodiment, and includes a commercially available spot air conditioner ("JA-SPH25J" manufactured by HAIER Corporation) and supply member 4. This commercially available spot air conditioner has a configuration in which heat exchange system 2 and a condenser are disposed in the same housing, and air that has passed through heat exchanger (evaporator) 3 and air that has passed through the condenser are separately discharged. In the application device of Example 2, four columnar supply members 4 having a long side extending in the horizontal direction are disposed apart from each other at an introduction port that is disposed on an equipment side surface and introduces air into heat exchanger 3. Furthermore, the application device of Comparative Example 2 is similar to the application device of Example 2 except that supply member 4 is not used. In Test 2, the application device of Example 2 and the application device of Comparative Example 2 were driven, and a performance difference between the application device of Example 2 and the application device of Comparative Example 2 was confirmed.
As a result, in the application device of Example 2, it was confirmed that the power consumption was reduced as the humidity became higher in a temperature range of 10°C or higher and 35°C or lower under the condition that a suction wind speed was set to 1 m/s. Furthermore, in the application device of Example 2, it was confirmed that the power consumption was reduced as the suction wind speed was lower in a range of the suction wind speed of 4 m/s or less. Furthermore, in the application device of Example 2, it was confirmed that a dehumidification amount increased as the absolute environmental humidity increased in a range where the absolute environmental humidity was 30.0 g/m³ or less, as compared with the application device of Comparative Example 2. Furthermore, under an environment of an air temperature of 27 degrees and a humidity of 70%, it was confirmed that the application device of Example 2 had a lower relative humidity value at an air outlet and a lower temperature of the air discharged from the air outlet than the application device of Comparative Example 2. As a result, it was found that the application device of Example 2 had stable dehumidifying performance and cooling function in this test range.

[Test 3]

Test 3 was performed using a mixture of the additive supplied from supply member 4 and water (Examples 3A and 3B) and water (Comparative Example 3). Example 3A contains the additive at a concentration of 100 ppm and Example 3B contains the additive at a concentration of 1000 ppm. The mixture of the additives of Examples 3A and 3B and water, and the water of Comparative Example 3 were spread on the surface of the drain pan of the air conditioning device, and a remaining amount of water on the surface of the drain pan after a lapse of a certain period of time was checked.
As a result, in both Examples 3A and 3B, it was confirmed that the remaining amount of water was suppressed to about half or less as compared with Comparative Example 3. Furthermore, it was confirmed that the remaining amount of water in Example 3B was smaller than that in Example 3A. As a result, it has been found that when supply member 4 is used, a thin water membrane is formed by bringing the additive into contact with moisture, and the moisture can be removed from the attached surface at an early stage. Therefore, when supply member 4 is applied to heat exchanger 3, it is considered that moisture can be prevented from remaining in fins 5, and generation of mold and the like on the surface of fins 5 can be suppressed.

[Test 4]

Next, Test 4 was performed using an application device according to Example 8 of the present disclosure. The application device of Example 8 is a large air conditioning device, and includes heat exchange system 2 mounted on an indoor unit of the large air conditioning device. A substantially rectangular parallelepiped section (including a plurality of fins 5 and flow pipe 6) having a predetermined size (length: 17.5 cm, width: 9.5 cm, thickness: 9 mm) was cut out from heat exchanger 3 having the plurality of fins 5 of heat exchange system 2 of Example 8. The initial weight of the section was measured by a balance in a state where the section was suspended. Thereafter, a mixed solution obtained by mixing an additive having a predetermined concentration with water using a dropper was supplied to the section. As the additive, "EMLTLGEN LS-106" manufactured by Kao Corporation, which is a nonionic surfactant containing a polyoxyalkylene alkyl ether, was used.

After the mixed liquid started to drip from the section and the section was left for further 3 minutes from the time point when the amount of the mixed liquid supplied to the section was saturated, the weight of the section was measured, and the water capacity of the section was measured by a difference between the measured weight and the initial weight. Table 1 shows the test results. Table 1 shows a measured value of the water capacity of the section measured twice for a mixed solution of each additive concentration, a water capacity average value which is an average value of the two measured values, and a water capacity ratio B/A of the water capacity average value B when the additive concentration is each concentration to the water capacity average value A when the additive concentration is 0.

[Table 1]

	Water capacity of section
Additive concentration (ppm)	Water capacity (g) of section (first measurement)	Water capacity (g) of section (second measurement)	Water capacity average value (g)	Water capacity ratio
0	14.84	15.08	14.96	1.00
20	8.85	9.28	9.07	0.61
50	6.03	6.55	6.29	0.42
100	5.28	5.67	5.48	0.37
250	5.2	5.68	5.44	0.36
500	4.97	5.24	5.11	0.34
1000	5.1	5.53	5.32	0.36

As shown in Table 1, in this test range, it was confirmed that the water capacity of fins 5 can be reduced to almost 60% or less even when the additive concentration of the water (the mixed solution) to which the additive is supplied is several tens of ppm.

[Test 5]

Test 5 was performed using an application device according to Example 4 of the present disclosure and an application device of Comparative Example 4. The application device of Example 4 has the same configuration as the application device driven as the heating device according to the modification example of the second exemplary embodiment. The outdoor unit of the application device of Example 4 includes a plurality of heat exchangers 3 disposed in an up and down (vertical) direction and a horizontal direction in an installed state. In the application device of Example 4, among the plurality of heat exchangers 3 disposed in the horizontal direction, the plurality of elongated supply members 4 is disposed with the longitudinal direction horizontal so as to surround a part of the side surface of heat exchanger 3 with respect to heat exchanger 3 located outside the outdoor unit. Furthermore, the application device of Comparative Example 4 is similar to the application device of Example 4 except that supply members 4 are not provided.
In Test 5, a relationship between a low-temperature heating capacity (kW) in accordance with JIS C 9612:2013 and an operation cycle time was examined for each application device of Example 4 and Comparative Example 4. The operation cycle time is a combination of a time (heating time) required for a temperature rise to a target indoor temperature (20°C) and a time (defrosting time) required for defrosting. In the test, an outdoor dry-bulb temperature was 2°C, an outdoor wet-bulb temperature was 1°C, an indoor dry-bulb temperature was 20°C, and an indoor wet-bulb temperature was 14.5°C. Each application device of Example 4 and Comparative Example 4 was set so that the defrosting mechanisms of Example 4 and Comparative Example 4 operate when a pipe temperature of each of the heat exchangers of Example 4 and Comparative Example 4 became lower than or equal to a reference temperature.
Fig. 7 is a graph illustrating the relationship between the operation cycle time and the heating capability of each application device of Example 4 and Comparative Example 4 in the test result of Test 5. As illustrated in Fig. 7, in the application device of Example 4, the heating capability was slightly improved (about 1%) as compared with the application device of Comparative Example 4. Furthermore, in the application device of Example 4, as compared with Comparative Example 4, the time until frost adheres to fins 5 of heat exchanger 3 after the start of the heating operation was short, and the gradient of capacity decrease after the peak of the heating capacity was large. However, in the application device of Example 4, the defrosting time was shortened as compared with the application device of Comparative Example 4. As a result, it was confirmed that an operation rate over the entire operation cycle time of the application device of Example 4 was higher than that of the application device of Comparative Example 4. Specifically, in this test, it was confirmed that the operation efficiency of the application device of Example 4 was improved by about 3% or more as compared with the application device of Comparative Example 4. Furthermore, in the application device of Example 4, it was confirmed that the stopping time of the heating operation during defrosting was reduced by 25% as compared with the application device of Comparative Example 4. As a result, it was found that the application device of Example 4 can reduce the time when the heating is stopped and the user feels cold during the defrosting operation.

[Test 6]

Test 6 was performed using an application device according to Example 5 of the present disclosure and each application device of Comparative Examples 6 and 7. The application device of Example 5 has the same configuration as application device 101 which is the freezing device according to the second exemplary embodiment. In the application device of Example 5, a plurality of cylindrical supply members 4 whose longitudinal lengths extend in the horizontal direction are disposed. Furthermore, the application device of Comparative Example 6 is similar to the application device of Example 5 except that supply members 4 are not provided. Furthermore, the application device of Comparative Example 7 is the same as that of Comparative Example 6 except that a hydrophilic membrane is disposed on fins of a heat exchanger of Comparative Example 7. As a base configuration of each application device of Example 5 and Comparative Examples 6 and 7, a refrigerator "NR-F606WPX" manufactured by Panasonic Corporation was used. Each application device of Example 5 and Comparative Examples 6 and 7 was placed in a test chamber in which an air conditioning temperature was set to 25°C and humidity was not controlled (about 20 RH%).
In a metal tray were prepared a plurality of sets of test articles containing one sheet of paper waste ("Kimtowel" manufactured by Nippon Paper Group, Inc. Cresia Co., Ltd.) and 200 mL of pure water. Using these test articles, a moisture load was applied to each application device of Example 5 and Comparative Examples 6 and 7 so that frost was adhered to each of the heat exchangers of Example 5 and Comparative Examples 6 and 7 by pure water in the metal tray. Furthermore, the application devices of Example 5 and Comparative Examples 6 and 7 were set such that the defrosting operation was started every 13 hours, and the defrosting operation was ended when the ambient temperature at a predetermined position of each heat exchanger of Example 5 and Comparative Examples 6 and 7 reached 10°C during the defrosting operation.

Furthermore, the application devices of Example 5 and Comparative Examples 6 and 7 were driven by applying loads of different load levels ("Low level", "Medium level 1", "High level", and "Medium level 2") in the same order for a certain period of time. Table 2 shows setting contents of each load level. Table 2 shows, as the type of load, an opening/closing load indicating the degree of opening/closing of the door, and an internal load indicating the number of test articles to be disposed. Specifically, as illustrated in Table 2, in the "Low level", a total of three sets of test articles were used, and two sets of test articles were disposed in the refrigerating chamber (similar to refrigerating chamber 102) and one set of test articles was disposed in the vegetable chamber (similar to vegetable chamber 104). Furthermore, in "Medium level 1", "High level", and "Medium level 2", a total of five sets of test articles were used. Among them, four sets of test articles were disposed in the refrigerating chamber, and one set of test articles was disposed in the vegetable chamber. As illustrated in Table 2, "Medium level 2" has a larger load than "Low level" in that the number of test articles is larger than "Low level", and has a smaller load than "Medium level 1" in that there is no door opening/closing load.

[Table 2]

Load level	Opening/closing load	Internal load
Low	None		3 sets of test articles
Medium level 1	Door opening/closing 1 minute × 4 times/day	5 sets of test articles
High	Open vegetable chamber door by 8 mm	5 sets of test articles
Medium level 1	None	5 sets of test articles

Fig. 8 is a graph illustrating a relationship between the number of defrosting times and the defrosting time of each application device of Example 5 and Comparative Examples 6 and 7 in the test results of Test 6. Fig. 9 is a graph illustrating a relationship between the number of defrosting times and the cooling time of each application device of Example 5 and Comparative Examples 6 and 7 in the test results of Test 6. In the figures, "Medium 1" represents "Medium level 1", and "Medium 2" represents "Medium level 2". As illustrated in Fig. 8, it was confirmed that the defrosting time of the application device of Example 5 was shortened at all load levels as compared with the application devices of Comparative Examples 6 and 7. Furthermore, it was confirmed that the defrosting time was longer in the order of the application device of Example 5, the application device of Comparative Example 7, and the application device of Comparative Example 6. Furthermore, as illustrated in Fig. 9, the application device of Example 5 was found to be able to maintain the re-cooling time after defrosting at substantially the initial value even when the load level was any of "Low level", "Medium level 1", and "Medium level 2". As illustrated in Figs. 8 and 9, in each application device of Comparative Examples 6 and 7, an accumulation amount of frost adhering to and remaining in each of the heat exchangers of Comparative Examples 6 and 7 increased with an increase in the number of times of defrosting (elapse of operating time of each application device of Comparative Examples 6 and 7). Therefore, both the defrosting time and the re-cooling time after defrosting increased in each application device of Comparative Examples 6 and 7 as compared with the application device of Example 5.
Furthermore, according to another test, when the load level was "Low level", the application device of Example 5 was able to reduce the power consumption during the defrosting time by 38.1% as compared with the application device of Comparative Example 6. Furthermore, in this case, it was confirmed that the application device of Example 5 can reduce the power consumption (total power consumption during start-up, stabilization, immediately before defrosting operation, during defrosting operation, and re-cooling period after defrosting) of the entire operation by 12% as compared with the application device of Comparative Example 6.
Here, Fig. 10 is a diagram illustrating a photograph of heat exchanger 3 of Example 5 before defrosting. Fig. 11 is a diagram illustrating a photograph of heat exchanger 3 of Example 5 after defrosting. Fig. 12 is a diagram illustrating a photograph of the heat exchanger of Comparative Example 6 before defrosting. Fig. 13 is diagram illustrating a photograph of the heat exchanger of Comparative Example 6 after defrosting. Fig. 14 is a diagram illustrating a photograph of the heat exchanger of Comparative Example 7 before defrosting. Fig. 15 is a diagram illustrating a photograph of the heat exchanger of Comparative Example 7 after defrosting. Figs. 11, 13, and 15 illustrate states of the heat exchangers according to Example 5 and Comparative Examples 6 and 7 immediately after the seventeenth defrosting operation is performed after the operation of each application device according to Example 5 and Comparative Examples 6 and 7 is started.
As illustrated in Figs. 10 and 11, in the application device of Example 5, it has been confirmed that almost all frost adhering to heat exchanger 3 is defrosted by the defrosting operation in any of the load levels of "Low level", "Medium level 1", and "Medium level 2". Furthermore, in the application device of Example 5, no bridge of frost formed to connect adjacent fins 5 was confirmed in any of the above load levels. As illustrated in Figs. 12 and 13, it has been found that in the application device of Comparative Example 6, a considerable amount of waterdrop frost remains in the fins of Comparative Example 6 even after the defrosting operation, and frost accumulates. Furthermore, in the application device of Comparative Example 6, it was confirmed that the bridge was formed on a lower side of the heat exchanger of Comparative Example 6. Furthermore, as illustrated in Figs. 14 and 15, in the application device of Comparative Example 7, it was confirmed that a certain amount of frost was defrosted by the defrosting operation. However, in the application device of Comparative Example 7, it was confirmed that a lump of frost in a waterdrop shape locally remained on the end parts and the end surfaces of the fins of the heat exchanger of Comparative Example 7 in which the hydrophilic membrane was not disposed, and the surface of the flow pipe of Comparative Example 7.
The reason why the defrosting effect of the application device of Example 5 is high as described above is considered that moisture adhering to fins 5 is modified by the additive supplied by supply member 4. That is, in the application device of Example 5, the moisture adhering to fins 5 is modified by coming into contact with the additive, and the moisture slides down from fins 5 to promote drainage (liquid runout). On the other hand, in the application device of Comparative Example 7, moisture is easily removed to some extent by the action of the hydrophilic membrane disposed on the surfaces of the fins of Comparative Example 7, but the moisture itself is not modified. Therefore, it is considered that in a part of the fins without the hydrophilic membrane in the application device of Comparative Example 7, moisture hardly slips down from the fins of Comparative Example 7. Furthermore, in the application device of Comparative Example 6, moisture was not modified by the additive, and a hydrophilic membrane was not disposed on the surfaces of the fins of Comparative Example 6. Therefore, it is considered that moisture was relatively likely to adhere to the surfaces of the fins of Comparative Example 6 before and after defrosting.
Fig. 16 is a graph illustrating a relationship between the operating time and the freezing chamber temperature of each application device of Example 5 and Comparative Example 6 in the test result of Test 6. Fig. 16 illustrates a comparison result between the application device of Example 5 and the application device of Comparative Example 6 at the load level of "High level". As illustrated in Fig. 16, in the application device of Example 5, even when the load level was "High level", the internal temperature was stable as compared with the application device of Comparative Example 6, and it was confirmed that the temperature rise in the freezing chamber (similar to freezing chamber 103) during the defrosting operation was 4.4°C at the maximum. On the other hand, under similar conditions, it was confirmed that the temperature rise of the application device of Comparative Example 6 reached 11.1°C at the maximum.
Fig. 17 is a graph illustrating a relationship between the number of times of defrosting and the freezing chamber temperature in each application device of Example 5 and Comparative Examples 6 and 7 in the test result of Test 6. As illustrated in Fig. 17, even when the load level is changed among "Low level", "Medium level 1", "High level", and "Medium level 2", it was confirmed that the application device of Example 5 can suppress the temperature change in the freezer during the defrosting operation as compared with each application device of Comparative Examples 6 and 7. It is considered that the application device of Example 5 can stably maintain the temperature in the refrigerator and improve the refrigerating quality and the freezing quality.
The present disclosure is not limited to the above exemplary embodiments, and the configuration and method can be changed, added, or deleted without departing from the gist of the present disclosure. The additive supplied by supply member 4 only needs to reduce the contact angle with respect to fins 5, and may contain a plurality of components. When the additive contains a plurality of components, the additive may contain, for example, a first component having a function of reducing the contact angle of moisture with respect to fins 5, and a second component that activates the function of the first component so as to reduce the contact angle.
Furthermore, the arrangement method of supply member 4 is not limited as long as supply member 4 supplies an additive for reducing the contact angle with respect to fins 5 to the moisture attached to fins 5. Therefore, for example, supply member 4 and fins 5 may be disposed apart from each other. In this case, the additive of supply member 4 may be dropped onto the moisture adhering to fins 5, or the additive may be supplied through a member separate from supply member 4.

REFERENCE MARKS IN THE DRAWINGS

1: application device
2: heat exchange system
3: heat exchanger
3a: block
3b: block
3c: block
4: supply member
5: fin
6: flow pipe
7: filter
8: drain pan
9: drain pan
10: indoor unit
11: fan
40: carrier
41: support
101: application device
102: refrigerating chamber
103: freezing chamber
104: vegetable chamber
105: defrosting mechanism

Claims

A heat exchange system comprising:
a heat exchanger including a plurality of fins in contact with air containing moisture, the heat exchanger being configured to conduct cooling of the air by heat exchange via the plurality of fins between a refrigerant flowing inside the heat exchanger and the air; and

a supply member that supplies an additive that reduces a contact angle with respect to of each of the plurality of fins to the moisture attached to the plurality of fins by the cooling of the heat exchanger.
The heat exchange system according to Claim 1, wherein the additive is supplied from the supply member to the moisture attached to the plurality of fins by free fall.
The heat exchange system according to Claim 1 or 2, wherein the supply member is disposed in contact with the plurality of fins.
The heat exchange system according to Claim 3, wherein
the plurality of fins extends in a vertical direction and is arranged side by side in an intersecting direction intersecting the vertical direction, and

the supply member has an elongated shape in the intersecting direction, and is disposed to be in contact with end surfaces of the plurality of fins.
The heat exchange system according to any one of Claims 1 to 4, wherein the supply member is detachably disposed with respect to the heat exchanger.
The heat exchange system according to any one of Claims 1 to 5, wherein the supply member includes a plurality of carriers that carry the additive, and a support that supports the plurality of carriers in a state where the plurality of carriers is dispersed, the additive being releasable from the plurality of carriers to an outside of the supply member.
The heat exchange system according to Claim 6, wherein the plurality of carriers are porous granules.
The heat exchange system according to any one of Claims 1 to 7, wherein the additive is a surfactant.
The heat exchange system according to any one of Claims 1 to 8, wherein the additive dissolves, disperses, or diffuses with respect to the moisture attached to the plurality of fins.
An application device comprising the heat exchange system according to any one of Claims 1 to 9.
The application device according to Claim 10, being an air conditioning device including an indoor unit,
wherein the heat exchange system is mounted on the indoor unit.
The application device according to Claim 10 or 11, being an air conditioning device including an outdoor unit, the application device comprising a defrosting mechanism that removes frost adhering to the heat exchanger,
wherein the heat exchange system is mounted on the outdoor unit.
The application device according to Claim 10, being a freezing device including a defrosting mechanism that removes frost adhering to the heat exchanger, the freezing device configured to refrigerate or freeze an object.