Heat transmission device

Abstract

A heat transmission device (1000) comprises a first heat medium circuit (C1) and a second heat medium circuit (C2). The first heat medium circuit (C1) is provided with a first heat-radiating unit (13) that radiates heat from a first heat medium, and a first heat-receiving unit (17) that receives heat and provides the heat to the first heat medium. The second heat medium circuit (C2) is provided with a second heat-radiating unit (24) that radiates heat from a second heat medium, and a second heat-receiving unit (27) that receives heat and provides the heat to the second heat medium. The second heat-radiating unit (24) is configured to radiate heat provided from the second heat medium as radiant heat. The first heat-receiving unit (17) is configured to receive the radiant heat radiated from the second heat-radiating unit and provide the radiant heat to the first heat medium.

Description

Heat Transfer Device

[0001] The present disclosure relates to heat transfer devices.

[0002] Devices that exchange heat between a space to be cooled or heated and the outside include heat pump devices, refrigeration cycle devices, etc. Some of these devices use multiple types of heat transfer media.

[0003] For example, International Publication No. 2021 / 106084 (Patent Document 1) discloses a two-stage refrigeration cycle device that uses a flammable refrigerant as a high-stage side refrigerant and a non-flammable refrigerant as a low-stage side refrigerant.

[0004] International Publication No. 2021 / 106084

[0005] When a flammable refrigerant is used in the high-temperature side circuit, in a system in which the refrigerant and the refrigerant or heat transfer medium are exchanged in adjacent flow paths, such as a plate heat exchanger, if the heat exchanger becomes corroded or damaged, the refrigerant on the high-temperature side may mix with the refrigerant on the low-temperature side, causing flammable refrigerant to flow into the room.Not only this, but in systems that use multiple types of heat transfer mediums and exchange heat between them, there is a risk of different heat transfer mediums mixing due to corrosion of the plate heat exchanger, etc.

[0006] The present disclosure is intended to solve the above-mentioned problems, and has an object to provide a heat transfer device in which the risk of mixing between heat transfer media is reduced.

[0007] The present disclosure relates to a heat transfer device. The heat transfer device includes a first heat medium circuit through which a first heat medium circulates and a second heat medium circuit through which a second heat medium circulates. The first heat medium circuit includes a first heat radiating section that radiates heat from the first heat medium and a first heat receiving section that receives heat and provides it to the first heat medium. The second heat medium circuit includes a second heat radiating section that radiates heat from the second heat medium and a second heat receiving section that receives heat and provides it to the second heat medium. The second heat radiating section is configured to radiate heat provided by the second heat medium as radiant heat. The first heat receiving section is configured to receive radiant heat radiated from the second heat radiating section and provide it to the first heat medium.

[0008] According to the heat transfer device of the present disclosure, the two heat medium circuits are separated, reducing the risk of different heat mediums mixing with each other.

[0009] Fig. 1 is a diagram showing a configuration of a heat transfer device according to a first embodiment. Fig. 2 is a diagram showing a configuration of a heat transfer device according to a modified example of the first embodiment. Fig. 3 is a diagram showing a configuration of a heat transfer device according to a second embodiment. Fig. 4 is a diagram showing a configuration of a heat transfer device according to a modified example of the second embodiment. Fig. 5 is a diagram showing a configuration of a heat transfer unit 100A.

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Below, embodiments including multiple modifications will be described, but it was originally intended that the configurations described in each embodiment be combined as appropriate. Note that identical or corresponding parts in the drawings will be designated by the same reference numerals, and their description will not be repeated.

[0011] Embodiment 1. Fig. 1 is a diagram showing the configuration of a heat transfer device according to embodiment 1. The heat transfer device 1000 shown in Fig. 1 includes a first heat medium circuit C1 through which a first heat medium circulates and a second heat medium circuit C2 through which a second heat medium circulates. In embodiment 1, both the first heat medium and the second heat medium use refrigerants that condense and evaporate during circulation.

[0012] The first heat medium circuit C1 includes a first heat radiating section 13 that radiates heat from the first heat medium and a first heat receiving section 17 that receives heat and provides it to the first heat medium. In the first embodiment, the first heat radiating section 13 is a condenser that performs heat exchange between outside air and the refrigerant using a fan 13F. The first heat medium circuit C1 also includes a pressure reducing device 15. The pressure reducing device 15 is, for example, an expansion valve that reduces the pressure of the refrigerant condensed in the first heat radiating section 13 and flows the reduced pressure to the first heat receiving section 17.

[0013] The second heat medium circuit C2 includes a second heat radiating section 24 that radiates heat from the second heat medium and a second heat receiving section 27 that receives heat and provides it to the second heat medium. In the first embodiment, the second heat receiving section 27 is an evaporator that performs heat exchange between the indoor air and the refrigerant using a fan 27F. The first heat medium circuit C1 also includes a pressure reducing device 25. The pressure reducing device 25 is, for example, an expansion valve that reduces the pressure of the refrigerant condensed in the second heat radiating section 24 and flows the refrigerant to the second heat receiving section 27.

[0014] For example, propane (R290) is used as the first heat medium and CO ２ It is conceivable to use refrigerant R744. In this case, the heat transfer device 1000 is a cascade refrigeration cycle device. In recent years, the use of flammable refrigerants has been considered due to their low global warming potential. However, flammable refrigerants are preferably used outdoors because their concentration in the air tends to increase if they leak indoors. Therefore, a flammable refrigerant is used on the high-side side, and a non-flammable refrigerant is used on the low-side side.

[0015] In a cascade refrigeration cycle system, a plate heat exchanger or the like is often used to exchange heat between the high-side refrigerant and the low-side refrigerant. However, since the high-side refrigerant and the low-side refrigerant exchange heat through a single metal layer in a plate heat exchanger, if a hole develops in the metal layer due to corrosion or the like, the high-side refrigerant may be mixed with the low-side refrigerant. This would result in a portion of the flammable refrigerant circulating in the indoor evaporator, which is undesirable in the event of a leak.

[0016] Therefore, in the first embodiment, thermal radiation is used to transfer heat from the low-temperature side to the high-temperature side. All objects emit electromagnetic waves carrying thermal energy, i.e., light. The heat transfer unit 100 transports this light and performs radiant heat transfer, which is absorbed by the object. The heat transfer unit 100 is composed of a second heat radiating unit 24 and a first heat receiving unit 17. The second heat radiating unit 24 is configured to emit heat provided by the second heat medium as radiant heat, as indicated by the arrows. The first heat receiving unit 17 is configured to receive the radiant heat provided by the second heat radiating unit and provide it to the first heat medium.

[0017] The heat radiating section 24 is a radiant heat exchanger in which the surface area with the highest emissivity is the largest, and the heat receiving section 17 is a radiant heat exchanger in which the surface area with the highest absorptivity is the largest.

[0018] In this way, by transferring heat by radiation, the first heat medium circuit C1 and the second heat medium circuit C2 can be physically separated, thereby reducing the possibility of the high-temperature side refrigerant being mixed with the low-temperature side refrigerant.

[0019] The first heat medium circuit C1 is a refrigeration cycle device, and is configured so that a refrigerant such as propane (R290) flows through the compressor 11, the heat dissipation section 13 (condenser), the pressure reduction device 15 (expansion valve), and the heat receiving section 17 (evaporator) in this order, and then returns to the compressor 11.

[0020] The second heat medium circuit C2 is a refrigeration cycle device. ２ A refrigerant such as R744 flows through the compressor 21, heat radiating section 24 (condenser), pressure reducing device 25 (expansion valve), and heat receiving section 27 (evaporator) in that order, before returning to the compressor 21. In FIG. 1, a heat exchanger 23 is disposed between the compressor 21 and the heat radiating section 24, and heat that cannot be fully removed by the heat radiating section 24 is previously radiated into the air (upstream) by the heat exchanger 23 and fan 23F. However, if the heat removed by the heat radiating section 24 is sufficient, the heat exchanger 23 is not necessarily provided.

[0021] Modification of First Embodiment. FIG. 2 is a diagram showing the configuration of a heat transfer device according to a modification of the first embodiment. The heat transfer device 1000A shown in FIG. 2 includes a first heat medium circuit C1 through which a first heat medium circulates and a second heat medium circuit C2A through which a second heat medium circulates. The configuration of the first heat medium circuit C1 is the same as that of the first embodiment. In addition, in the modification of the first embodiment, refrigerants that condense and evaporate during circulation are used as both the first heat medium and the second heat medium.

[0022] The second heat medium circuit C2A is obtained by switching the positions of the heat exchanger 23 and the heat radiator 24 in the second heat medium circuit C2 shown in Fig. 1. The other configurations of the second heat medium circuit C2A are the same as those of the second heat medium circuit C2, and therefore description thereof will not be repeated.

[0023] 2, the heat exchanger 23 is disposed between the heat radiating section 24 and the pressure reducing device 25, and the heat that cannot be completely removed by the heat radiating section 24 is later (downstream) radiated into the air by the heat exchanger 23 and the fan 23F. Depending on the temperature of the heat radiating section 24, it may be better to first radiate the radiant heat from the high-temperature refrigerant and then have the refrigerant exchange heat with the air.

[0024] In the modified example of the first embodiment, the possibility of refrigerant contamination can be reduced, similarly to the first embodiment.

[0025] Second Embodiment. Figure 3 is a diagram showing the configuration of a heat transfer device according to a second embodiment. The heat transfer device 1001 shown in Figure 3 includes a first heat medium circuit C1 through which a first heat medium circulates and a second heat medium circuit C12 through which a second heat medium circulates. In the first embodiment, the first heat medium is a refrigerant that condenses and evaporates during circulation, and the first heat medium circuit C1 is a refrigeration cycle device. On the other hand, the second heat medium is a liquid medium that maintains a liquid phase during circulation, such as water or brine.

[0026] The first heat medium circuit C1 includes a first heat radiating section 13 that radiates heat from the first heat medium and a first heat receiving section 17 that receives heat and provides it to the first heat medium. In the second embodiment, the first heat radiating section 13 is a condenser that performs heat exchange between outside air and the refrigerant using a fan 13F. The first heat medium circuit C1 also includes a pressure reducing device 15. The pressure reducing device 15 is, for example, an expansion valve that reduces the pressure of the refrigerant condensed in the first heat radiating section 13 and flows the reduced pressure to the first heat receiving section 17.

[0027] The second heat medium circuit C12 includes a second heat dissipation section 24 that dissipates heat from the second heat medium and a second heat receiving section 27 that receives heat and provides it to the second heat medium. In the second embodiment, the second heat receiving section 27 is also an evaporator that performs heat exchange between the indoor air and the refrigerant using a fan 27F.

[0028] The second heat medium circuit C12 further includes a liquid pump 35. In Fig. 3, the liquid pump 35 is disposed between the outlet of the heat radiating section 24 and the inlet of the second heat receiving section 27, but may be disposed anywhere on the circulation path of the liquid medium in the second heat medium circuit C12.

[0029] For example, a flammable refrigerant such as propane (R290) may be used as the first heat medium, and water or brine may be used as the second heat medium. Even in this case, if a plate heat exchanger or the like is used to exchange heat between the refrigerant and the water or brine, the flammable refrigerant may be contaminated with the water or brine if a hole develops in the metal layer due to corrosion or other reasons. This would result in a portion of the flammable refrigerant circulating in the indoor evaporator, which is undesirable in the event of a leak.

[0030] Therefore, in the second embodiment, heat radiation is also used to transfer heat from the refrigerant to the liquid medium. The heat transfer unit 100 is composed of a second heat radiating unit 24 and a first heat receiving unit 17. The second heat radiating unit 24 is configured to radiate heat provided by the second heat medium as radiant heat. The first heat receiving unit 17 is configured to receive the radiant heat radiated from the second heat radiating unit and provide it to the first heat medium. In this way, heat transfer by radiation can physically separate the first heat medium circuit C1 and the second heat medium circuit C12, thereby reducing the possibility of a flammable refrigerant being mixed into the water or brine.

[0031] The second heat medium circuit C12 is configured so that a liquid medium such as water or brine flows through the liquid pump 35, the heat receiving section 27 (evaporator), the heat radiating section 24 (condenser) in this order, and then returns to the liquid pump 35. In Fig. 3, the heat exchanger 23 is disposed between the heat receiving section 27 and the heat radiating section 24, and heat that cannot be completely removed by the heat radiating section 24 is previously radiated into the air (upstream) by the heat exchanger 23 and the fan 23F. However, if the heat radiating section 24 can sufficiently remove heat, the heat exchanger 23 is not necessarily provided.

[0032] Modification of Embodiment 2. FIG. 4 is a diagram showing the configuration of a heat transfer device according to a modification of Embodiment 2. The heat transfer device 1001A shown in FIG. 4 includes a first heat medium circuit C1 through which a first heat medium circulates and a second heat medium circuit C12A through which a second heat medium circulates. The configuration of the first heat medium circuit C1 is the same as that of Embodiment 2. Also in this modification of Embodiment 2, the first heat medium is a refrigerant that condenses and evaporates during circulation, and the first heat medium circuit C1 is a refrigeration cycle device. On the other hand, the second heat medium is a liquid medium that maintains a liquid phase during circulation, such as water or brine.

[0033] The second heat medium circuit C12A is obtained by switching the positions of the heat exchanger 23 and the heat radiator 24 in the second heat medium circuit C12 shown in Fig. 3. The other configurations of the second heat medium circuit C12A are the same as those of the second heat medium circuit C12, and therefore description thereof will not be repeated.

[0034] 4, the heat exchanger 23 is disposed between the heat radiating section 24 and the liquid pump 35, and the heat that cannot be completely removed by the heat radiating section 24 is later (downstream) radiated into the air by the heat exchanger 23 and the fan 23F. Depending on the temperature of the heat radiating section 24, it may be better to first radiate the radiant heat from the high-temperature refrigerant and then have the refrigerant exchange heat with the air.

[0035] In the modified example of the second embodiment, the possibility of refrigerant contamination can be reduced, similarly to the second embodiment.

[0036] Embodiment 3 In embodiment 3, in any of the heat transfer devices of embodiment 1, the modified embodiment of embodiment 1, embodiment 2, and the modified embodiment of embodiment 2, the configuration of the heat transfer unit 100 is changed to a heat transfer unit 100A.

[0037] FIG. 5 is a diagram showing the configuration of the heat transfer unit 100A. The heat transfer unit 100A includes a transparent columnar body 101 that transmits radiant heat emitted from the second heat dissipation unit 24 as indicated by the arrows and sends it to the first heat receiving unit 17. The columnar body 101 has a first end face 111, a second end face 112, and a side face 113. The columnar body 101 is disposed between the second heat dissipation unit 24 and the first heat receiving unit 17. The columnar body 101 is disposed so that the radiant heat emitted from the second heat dissipation unit 24 passes from the first end face 111 into the columnar body 101 and is sent from the second end face 112 to the first heat receiving unit 17. The columnar body 101 is configured to totally reflect radiant heat (light, infrared rays, radiation, etc.) from the second heat dissipation unit 24 toward the first heat receiving unit 17 on the inner surface of the side face 113. For example, a radiation transmission cable using total reflection, an optical fiber, or the like can be used as the transparent columnar body 101. Note that lenses may be disposed between the columnar body 101 and the first heat receiving part 17, and between the columnar body 101 and the second heat dissipating part 24, for example, to focus light.

[0038] The longer the distance, the more difficult it becomes to transport heat through the pipes through which the refrigerant passes, due to factors such as heat radiation or absorption loss, pressure loss, and refrigeration oil retention. Furthermore, due to the distance limitations on heat transport, it has been necessary to install the outdoor unit (heat source) close to the indoor unit (utilization equipment). For example, for a typical refrigerator, the connecting pipes connecting the indoor unit (such as a showcase) are limited to a length of 100 meters.

[0039] According to the heat transfer device of embodiment 3, the columnar body 101 can minimize losses, so that long-distance heat transfer is achieved by radiation, eliminating heat radiation / absorption losses and pressure losses, and enabling the provision of cold over a wide area.

[0040] [Summary] The present disclosure will be summarized again with reference to the drawings.

[0041] (Section 1) The present disclosure relates to a heat transfer device 1000. The heat transfer device 1000 includes a first heat medium circuit C1 through which a first heat medium circulates and a second heat medium circuit C2 through which a second heat medium circulates. The first heat medium circuit C1 includes a first heat radiating section 13 that radiates heat from the first heat medium and a first heat receiving section 17 that receives heat and provides it to the first heat medium. The second heat medium circuit C2 includes a second heat radiating section 24 that radiates heat from the second heat medium and a second heat receiving section 27 that receives heat and provides it to the second heat medium. The second heat radiating section 24 is configured to radiate heat provided by the second heat medium as radiant heat. The first heat receiving section 17 is configured to receive radiant heat radiated from the second heat radiating section and provide it to the first heat medium.

[0042] (Item 2) In the heat transfer device 1000 described in item 1, the first heat medium and the second heat medium are refrigerants that condense and evaporate during circulation. The first heat medium circuit C1 further includes a first compressor 11 that compresses the first heat medium that has passed through the first heat receiving portion 17, and a first pressure reducing device 15 that reduces the pressure of the first heat medium that has passed through the first heat radiating portion 13. The second heat medium circuit C2 further includes a second compressor 21 that compresses the second heat medium that has passed through the second heat receiving portion 27, and a second pressure reducing device 25 that reduces the pressure of the second heat medium that has passed through the second heat radiating portion 24.

[0043] (Section 3) In the heat transfer device 1000 described in Section 2, the second heat medium circuit C2 further includes a heat exchanger 23 arranged between the discharge portion of the second compressor 21 and the second heat dissipation portion 24, and configured to perform heat exchange between air and the second heat medium.

[0044] (Item 4) In the heat transfer device 1001 described in item 1, the first heat medium is a refrigerant that condenses and evaporates during circulation, and the second heat medium is a liquid medium that maintains a liquid phase during circulation. The first heat medium circuit C1 further includes a compressor 11 that compresses the first heat medium that has passed through the first heat receiving portion 17, and a pressure reducing device 15 that reduces the pressure of the first heat medium that has passed through the first heat radiating portion 13. The second heat medium circuit C12 is arranged between the second heat receiving portion 27 and the second heat radiating portion 24, and further includes a liquid pump 35 that circulates the second heat medium.

[0045] (5) In the heat transfer device 1001 described in 4, the second heat medium circuit C12 further includes a heat exchanger 23 arranged in a flow path through which the second heat medium flows from the second heat receiving portion 27 toward the second heat dissipation portion 24, and configured to exchange heat between air and the second heat medium.

[0046] (Item 6) The heat transfer device described in any one of Items 1 to 5 further includes a transparent columnar body 101 having a first end face 111, a second end face 112, and a side face 113. The columnar body is arranged so that radiant heat emitted from the second heat dissipation unit 24 passes from the first end face 111 into the columnar body 101 and is sent from the second end face 112 to the first heat receiving unit 17. The columnar body 101 is configured so that radiant heat (infrared rays) directed from the second heat dissipation unit 24 toward the first heat receiving unit 17 is totally reflected by the inner surface of the side face.

[0047] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims.

[0048] 11, 21 Compressor, 13, 24 Heat dissipation section, 13F, 23F, 27F Fan, 15, 25 Pressure reduction device, 17, 27 Heat receiving section, 23 Heat exchanger, 35 Liquid pump, 100, 100A Heat transfer section, 101 Columnar body, 1000, 1000A, 1001, 1001A Heat transfer device, C1 First heat medium circuit, C2A, C2, C12A, C12 Second heat medium circuit.

Claims

1. A heat transfer device comprising: a first heat medium circuit through which a first heat medium circulates; and a second heat medium circuit through which a second heat medium circulates; the first heat medium circuit comprising: a first heat radiating section which radiates heat from the first heat medium; and a first heat receiving section which receives heat and provides it to the first heat medium; the second heat medium circuit comprising: a second heat radiating section which radiates heat from the second heat medium; and a second heat receiving section which receives heat and provides it to the second heat medium; the second heat radiating section is configured to radiate the heat provided by the second heat medium as radiant heat; and the first heat receiving section is configured to receive the radiant heat radiated from the second heat radiating section and provide heat to the first heat medium.

2. A heat transfer device as described in claim 1, wherein the first heat medium and the second heat medium are refrigerants which condense and evaporate during circulation, the first heat medium circuit further comprises a first compressor which compresses the first heat medium which has passed through the first heat receiving portion, and a first pressure reducing device which reduces the pressure of the first heat medium which has passed through the first heat radiating portion, and the second heat medium circuit further comprises a second compressor which compresses the second heat medium which has passed through the second heat receiving portion, and a second pressure reducing device which reduces the pressure of the second heat medium which has passed through the second heat radiating portion.

3. The heat transfer device as described in claim 2, wherein the second heat medium circuit further includes a heat exchanger arranged between the discharge portion of the second compressor and the second heat dissipation portion and configured to perform heat exchange between air and the second heat medium.

4. The heat transfer device described in claim 1, wherein the first heat medium is a refrigerant that condenses and evaporates during circulation, the second heat medium is a liquid medium that maintains a liquid phase state during circulation, the first heat medium circuit further includes a compressor that compresses the first heat medium that has passed through the first heat receiving portion and a pressure reducing device that reduces the pressure of the first heat medium that has passed through the first heat radiating portion, and the second heat medium circuit further includes a liquid pump that is disposed between the second heat receiving portion and the second heat radiating portion and circulates the second heat medium.

5. The heat transfer device described in claim 4, wherein the second heat medium circuit is arranged in a flow path through which the second heat medium flows from the second heat receiving portion to the second heat radiating portion, and further includes a heat exchanger configured to exchange heat between air and the second heat medium.

6. A heat transfer device as described in any one of claims 1 to 5, further comprising a transparent columnar body having a first end face, a second end face, and a side face, the columnar body being arranged so that radiant heat emitted from the second heat dissipation section passes from the first end face into the columnar body and is sent from the second end face to the first heat receiving section, and the columnar body is configured to totally reflect the radiant heat directed from the second heat dissipation section toward the first heat receiving section at the inner surface of the side face.

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