Refrigeration cycle device

Abstract

This refrigeration cycle device includes a condenser in which a refrigerant circulates, a fan that blows air to the condenser, a sprinkler device that sprinkles water on the condenser, and a control device that continues an operation of the fan after the end of a sprinkle operation by the sprinkler device.

Description

Refrigeration cycle equipment

[0001] The present disclosure relates to a refrigeration cycle device that sprays water onto a condenser.

[0002] In a refrigeration cycle device, when the outside air temperature is high, it is known to spray water on the air heat exchanger that serves as the condenser in the outdoor unit, and cool the condenser using the heat of vaporization of the water, thereby improving the condensation capacity of the refrigerant.

[0003] For example, Patent Document 1 discloses a spraying device equipped with multiple spray nozzles for spraying water onto a heat exchanger with plate fins. In Patent Document 1, multiple spray nozzles are arranged in front of the heat exchanger, and a spraying operation is performed to spray mist-like water during cooling operation in which the heat exchanger functions as a condenser. The spraying operation reduces the condensation temperature and limits the output of the compressor's electric motor. After the spraying operation is completed, the compressor and fan motor are stopped, and the sprayed water adhering to the heat exchanger dries naturally by absorbing heat through thermal conduction or radiant heat from the surrounding air or the heat exchanger material with which the sprayed water is in contact. Furthermore, the water used for spraying water is generally tap water.

[0004] Patent No. 5880019

[0005] As in the case of Patent Document 1, the water used for sprinkling is tap water, which contains metal ions, and therefore corrosion occurs when it adheres to an aluminum air heat exchanger. If the water after sprinkling is dried by natural drying, which absorbs heat by heat conduction or radiant heat from the surrounding air or the heat exchanger material that the sprinkled liquid is in contact with, it takes time to dry, and corrosion progresses as the sprinkled liquid continues to be held in the heat exchanger.

[0006] An object of the present disclosure is to provide a refrigeration cycle device that can suppress the progression of corrosion when water is sprayed on an air heat exchanger made of aluminum material.

[0007] The refrigeration cycle device of the present disclosure includes a condenser through which a refrigerant flows, a blower that blows air onto the condenser, a sprinkler device that sprays water onto the condenser, and a control device that continues operating the blower after the sprinkler device has finished spraying water.

[0008] In the refrigeration cycle device according to the present disclosure, the operation of the blower continues after the end of the sprinkling operation, and the time it takes for the sprinkled liquid adhering to the air heat exchanger serving as the condenser to dry is shortened due to the heat absorption of the sprinkled liquid by heat transfer through forced convection. This shortens the time that the sprinkled liquid remains on the air heat exchanger, thereby suppressing corrosion of the air heat exchanger.

[0009] 1 is a schematic configuration diagram of a refrigeration cycle apparatus according to Embodiment 1. FIG. 2 is a functional configuration diagram of a control device of the refrigeration cycle apparatus according to Embodiment 1. FIG. 3 is a schematic perspective view of an outdoor heat exchanger according to Embodiment 1. FIG. 4 is a schematic configuration diagram illustrating a sprinkler device of the refrigeration cycle apparatus according to Embodiment 1. FIG. 5 is a schematic diagram illustrating the principle of corrosion by tap water in an outdoor heat exchanger. FIG. 6 is a schematic diagram illustrating the principle of galvanic corrosion in an outdoor heat exchanger. FIG. 7 is a flowchart illustrating processing of a drying operation in the refrigeration cycle apparatus according to Embodiment 1. FIG. 8 is a time chart illustrating control of a refrigeration cycle apparatus according to a comparative example. FIG. 9 is a time chart illustrating control of a refrigeration cycle apparatus according to Embodiment 1. FIG. 10 is a flowchart illustrating processing of a drying operation in a refrigeration cycle apparatus according to a modification of Embodiment 1. FIG. 11 is a time chart illustrating control of a refrigeration cycle apparatus according to a modification of Embodiment 1. FIG. 12 is a graph illustrating changes in inlet water temperature and outlet water temperature in a water heat exchanger when a cooling operation is performed in the refrigeration cycle apparatus according to Embodiment 1. FIG. 13 is a graph illustrating changes in inlet water temperature and outlet water temperature in a water heat exchanger when the cooling operation is stopped in the refrigeration cycle apparatus according to Embodiment 1. 1 is a graph showing the transitions of the inlet water temperature and the outlet water temperature in the water heat exchanger when a drying operation is performed after the cooling operation is stopped in the refrigeration cycle apparatus according to embodiment 1. FIG. 2 is a graph showing the transitions of the inlet water temperature and the outlet water temperature in the water heat exchanger when a drying operation is performed after the cooling operation is stopped in the refrigeration cycle apparatus according to a comparative example of embodiment 1. FIG. 3 is a flowchart illustrating the processing of the drying operation in the refrigeration cycle apparatus according to embodiment 2. FIG. 4 is a time chart in the control of the refrigeration cycle apparatus according to embodiment 2.

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the present disclosure is not limited to the embodiments described below. Furthermore, in the following drawings, including FIG. 1, the size relationships of the components may differ from the actual ones. Furthermore, in the following description, terms indicating directions are used as appropriate to facilitate understanding of the present disclosure, but these terms are used only to explain the present disclosure and do not limit the present disclosure. Examples of terms indicating directions include "up," "down," "right," "left," "front," and "rear."

[0011] Embodiment 1. <Configuration of Refrigeration Cycle Apparatus> Fig. 1 is a schematic configuration diagram of a refrigeration cycle apparatus 100 according to Embodiment 1. The refrigeration cycle apparatus 100 of this embodiment 1 is, for example, an air-cooled chilling unit that produces cold water.

[0012] As shown in FIG. 1, the refrigeration cycle device 100 is composed of a main circuit A and an injection circuit B. The main circuit A and the injection circuit B are refrigerant circuits in which a refrigerant circulates. As the refrigerant, for example, a single refrigerant such as R-22 or R-134a, a pseudo-azeotropic refrigerant mixture such as R-410A or R-404A, or a non-azeotropic refrigerant mixture such as R-407C can be used. In addition, as the refrigerant, a CF refrigerant containing a double bond in its chemical formula can be used. ３ CF=CH ２ Refrigerants with relatively low global warming potential, such as refrigerants or mixtures thereof, or CO ２ Alternatively, a natural refrigerant such as propane can be used.

[0013] <Configuration of Main Circuit A> The main circuit A is a refrigerant circuit in which a compressor 10, an outdoor heat exchanger 12, an internal heat exchanger 1, an expansion valve 13, a water heat exchanger 14, and an accumulator 15 are connected by piping. The compressor 10 compresses and discharges the refrigerant it draws in. The compressor 10 is driven via a compressor inverter drive device (not shown) or the like. The compressor 10 can change its capacity, which indicates the amount of refrigerant discharged per unit time, by arbitrarily changing its drive frequency based on instructions from the control device 3. A condensing temperature detection means 17 is provided between the compressor 10 and the outdoor heat exchanger 12 to detect the condensing temperature of the refrigerant discharged from the compressor 10. The condensing temperature detection means 17 is, for example, a pressure sensor. The control device 3 converts the pressure value detected by the condensing temperature detection means 17 into a saturation temperature to calculate the condensing temperature.

[0014] The outdoor heat exchanger 12 is an air heat exchanger that exchanges heat between the refrigerant and the outside air. During the cooling operation for cooling water, the outdoor heat exchanger 12 functions as a condenser, exchanging heat between the high-pressure refrigerant that has flowed in from the compressor 10 side and the air, thereby condensing and liquefying the refrigerant.

[0015] A sprinkler device 5 (see FIG. 4) is attached to the outdoor heat exchanger 12. The sprinkler device 5 sprinkles water onto the outdoor heat exchanger 12. The outdoor heat exchanger 12 and the sprinkler device 5 will be described in detail later.

[0016] The outdoor fan 16 sends air into the outdoor heat exchanger 12 to promote heat exchange between the refrigerant and the air. The outdoor fan 16 is driven via a fan inverter drive device (not shown) or the like. The outdoor fan 16 can change the airflow rate by arbitrarily changing the drive frequency based on instructions from the control device 3. The outdoor fans 16 correspond to the outdoor heat exchangers 12 on a one-to-one basis, for example. The correspondence between the outdoor fans 16 and the outdoor heat exchangers 12 is not limited to this. The outdoor fans 16 are an example of a blower.

[0017] The internal heat exchanger 1 has a first flow path 1 a and a second flow path 1 b. The internal heat exchanger 1 exchanges heat between a refrigerant flowing through the first flow path 1 a and a refrigerant flowing through the second flow path 1 b.

[0018] The water heat exchanger 14, which serves as a heat medium heat exchanger, exchanges heat between the refrigerant and water, which serves as a heat medium. The water heat exchanger 14 has a refrigerant flow path 14a through which the refrigerant from the main circuit A circulates and a water flow path 14b through which the water, which serves as a heat medium, circulates. The water heat exchanger 14 functions as an evaporator during cooling operation, exchanging heat between the refrigerant that flows in from the expansion valve 13 side and the water, evaporating the refrigerant and cooling the water.

[0019] The expansion valve 13, which serves as a throttling device, adjusts the pressure of the refrigerant passing through the water heat exchanger 14, for example, by changing its opening. The expansion valve 13 is configured, for example, as an electronic expansion valve that changes its opening based on instructions from the control device 3. However, the expansion valve 13 is not limited to this, and may be, for example, a temperature-sensitive expansion valve that changes its opening based on the temperature of the refrigerant.

[0020] The accumulators 15 are provided on the suction side of the compressors 10, respectively, and store surplus refrigerant in the refrigerant circuit.

[0021] <Configuration of Injection Circuit> The injection circuit B is a refrigerant circuit that branches off from the main circuit A between the internal heat exchanger 1 and the expansion valve 13 and is connected to the compressor 10 via the injection valve 19 and the internal heat exchanger 1. The injection circuit B branches off a portion of the refrigerant that has circulated through the internal heat exchanger 1 and circulates it. The injection circuit B causes medium-pressure refrigerant flowing between the internal heat exchanger 1 and the injection valve 19 to flow into the internal heat exchanger 1, thereby exchanging heat with high-pressure refrigerant flowing through the first flow path 1a. The injection circuit B is provided to reduce the refrigerant temperature in the first flow path 1a and to flow the refrigerant into the compressor 10, thereby suppressing the discharge temperature of the compressor 10.

[0022] The injection valve 19 expands and decompresses the refrigerant flowing through an injection circuit B branched off from the main circuit A. Like the expansion valve 13, the injection valve 19 is configured, for example, as an electronic expansion valve that changes its opening degree based on instructions from the control device 3. Note that the refrigeration cycle apparatus 100 may not have the injection circuit B.

[0023] <Configuration of Control Device 3> FIG. 2 is a functional configuration diagram of the control device 3 of the refrigeration cycle apparatus 100 according to the first embodiment. As shown in FIG. 2, the control device 3 includes a memory 7, a CPU 8, and a timer 6. The control device 3 controls the overall operation of the refrigeration cycle apparatus 100. The control device 3 is configured by a computer including the memory 7 and the CPU 8, dedicated hardware such as an ASIC or FPGA, or both. The memory 7 stores data and programs necessary for control. The CPU 8 executes the programs. The timer 6 measures time. The control device 3 controls each part of the refrigeration cycle apparatus 100 based on detection information from a temperature sensor or a pressure sensor included in the refrigeration cycle apparatus 100 and instructions from a remote control (not shown). Specifically, the control device 3 controls the drive frequency of the compressor 10, the rotation speed of the outdoor fan 16, the opening degree of the expansion valve 13, the sprinkling of water by the sprinkler device 5, etc.

[0024] <Configuration of outdoor heat exchanger 12> Fig. 3 is a schematic perspective view of the outdoor heat exchanger 12 according to embodiment 1. As shown in Fig. 3, the outdoor heat exchanger 12 includes a heat exchange section 120 including a plurality of heat transfer tubes 121 and a plurality of fins 122, and a header 123. The outdoor heat exchanger 12 is an air heat exchanger in which the refrigerant flowing through the heat transfer tubes 121 exchanges heat with air.

[0025] The outdoor heat exchanger 12 is, for example, a parallel flow condenser (PFC) heat exchanger. The outdoor heat exchanger 12 is made of, for example, aluminum. Aluminum is easy to manufacture into heat exchangers with micro- or mini-channels, such as flat tubes. Compared to copper, aluminum is easier to process and is less expensive. Using aluminum for the outdoor heat exchanger 12 enables the outdoor heat exchanger 12 to be made smaller, lighter, and more powerful, while also reducing its internal volume, i.e., the amount of refrigerant used. Reducing the amount of refrigerant used can address environmental issues.

[0026] The heat transfer tubes 121 are flat tubes with multiple flow paths formed therein. Each heat transfer tube 121 is arranged to extend between a pair of headers 123. The heat transfer tubes 121 are arranged at intervals in a direction perpendicular to the extension direction. The extension direction of each heat transfer tube 121 is, for example, the horizontal direction. The pair of headers 123 are arranged in a vertical direction perpendicular to the extension direction of each heat transfer tube 121. The direction perpendicular to the horizontal and vertical directions is referred to as the depth direction.

[0027] The fins 122 are corrugated fins having a wave-like folded shape. Each fin 122 is disposed to extend between a pair of headers 123. Each fin 122 is disposed between two adjacent heat transfer tubes 121 of the plurality of heat transfer tubes 121, and the two adjacent heat transfer tubes 121 are connected by the fin 122.

[0028] <Configuration of Sprinkler Device 5> Fig. 4 is a schematic diagram illustrating the configuration of the sprinkler device 5 of the refrigeration cycle apparatus 100 according to the first embodiment. As shown in Fig. 4, the sprinkler device 5 includes, for example, a first pipe 50a, a second pipe 50b, and connection pipes 52 connected to the first pipe 50a and the second pipe 50b. The sprinkler device 5 sprays water onto the outdoor heat exchanger 12, which is an air heat exchanger. This reduces the condensation temperature in the outdoor heat exchanger 12, and suppresses the output of the electric motor in the compressor 10.

[0029] The sprinkler device 5 is attached to, for example, a housing that holds the outdoor heat exchanger 12. The sprinkler device 5 and the outdoor heat exchanger 12 are arranged with a gap between them in the depth direction. The sprinkler device 5 performs sprinkler operation under the control of the control device 3. The sprinkler operation promotes improvement of the heat exchange efficiency of the outdoor heat exchanger 12.

[0030] The first pipe 50a and the second pipe 50b are independent of each other, and one end of the first pipe 50a and one end of the second pipe 50b are each connected to a connection pipe 52. The connection pipe 52 is connected to a water pipe or the like. Water flowing in from the connection pipe 52 is supplied to the first pipe 50a and the second pipe 50b, respectively. The connection pipe 52 is provided with a valve (not shown) that adjusts the water flow rate. The control device 3 controls the valve of the sprinkler device 5, thereby controlling the start and stop of sprinkling by the sprinkler device 5 and the amount of water sprinkled.

[0031] The first pipe 50a and the second pipe 50b are arranged opposite each other. The first pipe 50a is arranged to extend in the vertical direction outside one horizontal end of the heat exchanger 120. The second pipe 50b is arranged to extend in the vertical direction outside the other horizontal end of the heat exchanger 120.

[0032] The first pipe 50a is provided with a plurality of first nozzles 51a. For example, five first nozzles 51a are provided in the first pipe 50a. The number of first nozzles 51a may be four or less or six or more. Each first nozzle 51a is a hollow cone nozzle that sprays mist-like water at a spray angle of 60°, for example. The first nozzles 51a are arranged at intervals in the vertical direction and spray water toward the heat exchange unit 120. Each first nozzle 51a sprays water from one horizontal end of the outdoor heat exchanger 12 toward the center of the outdoor heat exchanger 12.

[0033] The second pipe 50b is provided with a plurality of second nozzles 51b. For example, five second nozzles 51b are provided in the second pipe 50b. The number of second nozzles 51b may be four or less or six or more. Each second nozzle 51b is a hollow cone nozzle that sprays mist-like water at a spray angle of 60°, for example. The second nozzles 51b are arranged at intervals in the vertical direction and spray water toward the heat exchange unit 120. Each second nozzle 51b sprays water from the other horizontal end of the outdoor heat exchanger 12 toward the center of the outdoor heat exchanger 12.

[0034] The sprinkler operation by the sprinkler device 5 is controlled by the control device 3. For example, when the cooling operation in which cold water is produced in the water heat exchanger 14 is completed, the control device 3 starts the sprinkler operation in which water is sprinkled by the sprinkler device 5.

[0035] <Principle of Corrosion> Figure 5 is a schematic diagram illustrating the principle of corrosion caused by tap water in the outdoor heat exchanger 12. As shown in Figure 5, if tap water continues to adhere to an aluminum material, the aluminum material will corrode. Tap water generally contains metal ions. When tap water adheres to an aluminum material, the metal ions contained in the tap water cause metal to precipitate from the tap water, and at the same time, the aluminum material is eluted. This reaction is called a substitution reaction. If tap water used for watering continues to adhere to the outdoor heat exchanger 12, which uses aluminum material, a substitution reaction occurs in the outdoor heat exchanger 12.

[0036] 6 is a schematic diagram illustrating the principle of galvanic corrosion in the outdoor heat exchanger 12. As shown in FIG. 6, metals precipitated from tap water by a substitution reaction undergo an oxidation-reduction reaction with aluminum material, resulting in galvanic corrosion. When tap water used for watering adheres to the outdoor heat exchanger 12, which uses aluminum material, substitution and oxidation-reduction reactions occur, causing corrosion of the aluminum material. Therefore, in the refrigeration cycle apparatus 100, after the watering operation is completed, a drying operation is performed in which the outdoor fan 16 and the compressor 10 continue to operate.

[0037] <Drying Operation> Figure 7 is a flowchart illustrating the processing of the drying operation in the refrigeration cycle apparatus 100 according to the first embodiment. As shown in Figure 7, in step S11, the control device 3 determines whether the sprinkler operation by the sprinkler device 5 has ended. When the cooling operation for producing chilled water ends, the control device 3 simultaneously ends the sprinkler operation by the sprinkler device 5 and starts the drying operation. In step S11, if the control device 3 determines that the sprinkler operation by the sprinkler device 5 has not ended (NO in step S11), the control device 3 repeats the processing, and if it determines that the sprinkler operation has ended (YES in step S11), the control device 3 proceeds to step S12.

[0038] In step S12, the control device 3 starts the operation of the timer 6, and proceeds to step S13 to determine whether the time measured by the timer 6 has reached the second time T2. If the control device 3 determines in step S13 that the time measured by the timer 6 has not reached the second time T2 (NO in step S13), the process is repeated. If the control device 3 determines in step S13 that the time measured by the timer 6 has reached the second time T2 (YES in step S13), the process proceeds to step S14.

[0039] In step S14, the control device 3 stops the operation of the compressor 10, and then proceeds to step S15.

[0040] In step S15, the control device 3 determines whether the time measured by the timer 6 has reached the first time T1. The first time T1 is longer than the second time T2. The first time T1 is, for example, one hour. The second time T2 is, for example, 30 minutes. In step S15, if the control device 3 determines that the time measured by the timer 6 has not reached the first time T1 (NO in step S15), the control device 3 repeats the process. In step S15, if the control device 3 determines that the time measured by the timer 6 has reached the first time T1 (YES in step S15), the control device 3 proceeds to step S16.

[0041] In step S16, the control device 3 stops the operation of the outdoor fan 16 and ends the process. In this way, after the spraying of water is completed, the control device 3 continues the operation of the fan motor of the outdoor fan 16 and the operation of the compressor 10 as the drying operation.

[0042] In the drying operation, after the spraying of water is completed, the fan motor of the outdoor fan 16 continues to operate for a certain period of time, for example, a first period of time T1. This forces convection to occur in the air around the outdoor heat exchanger 12, shortening the time it takes for the outdoor heat exchanger 12 to dry and preventing corrosion of the outdoor heat exchanger 12.

[0043] After the water spraying is completed, the compressor 10 continues to operate for a certain time, for example, a second time T2. This allows the high-temperature gas refrigerant to flow into the outdoor heat exchanger 12, which is an air heat exchanger, and heat is supplied to the sprayed water. This further shortens the time it takes for the outdoor heat exchanger 12 to dry, and prevents corrosion of the outdoor heat exchanger 12.

[0044] The control device 3 may control the fan motor of the outdoor fan 16 to continue operating for a first time T1 after the end of the sprinkler operation, and may control the compressor 10 to stop operating simultaneously with the end of the sprinkler operation. The first time T1 and the second time T2 may be set depending on the conditions of the environment or installation location in which the outdoor heat exchanger 12 is installed.

[0045] <Comparative Example> Fig. 8 is a time chart for controlling the refrigeration cycle apparatus 100 according to the comparative example. The vertical axis of Fig. 8 represents the on / off state and the dry state, and the horizontal axis represents time. As shown in Fig. 8, in the refrigeration cycle apparatus 100 according to the comparative example, when the sprinkler operation ends, the compressor 10 and the fan motor of the outdoor fan 16 are simultaneously stopped. The air heat exchanger requires a drying time from time T0 when the sprinkler operation ends to time Td1 until it dries. In this case, the sprinkler liquid adhering to the air heat exchanger dries naturally, so water remains retained in the air heat exchanger.

[0046] <Effects of Drying Operation> Figure 9 is a time chart for controlling the refrigeration cycle apparatus 100 according to the first embodiment. In Figure 9, the vertical axis represents the on / off state and the dry state, and the horizontal axis represents time. In Figure 9, the relationship between the amount of sprinkled liquid adhered and the outlet water temperature is shown by a solid line for the first embodiment and by a dashed line for the comparative example. The outlet water temperature is the temperature of the water flowing out of the water heat exchanger 14.

[0047] 9 , in the case of the first embodiment, the amount of adhering sprinkler liquid becomes zero when a time Td2, which is shorter than the time Td1, has elapsed from the time T0 when the sprinkler operation ended. By continuing to operate the compressor 10 and the outdoor fan 16 after the sprinkler operation ends, the decrease in the amount of adhering sprinkler liquid is promoted, and the drying time until the system becomes dry after the sprinkler operation ends is shortened from the time Td1 to the time Td2.

[0048] If the air heat exchanger has copper pipes, even if it is subjected to water spraying, the substitution reaction that occurs with aluminum materials will not occur. Also, if the air heat exchanger is a fin-tube type, even if it is subjected to water spraying, water is less likely to be retained between the fins and tubes, so corrosion is less likely to occur even if water is retained in the air heat exchanger for a long time.

[0049] On the other hand, the outdoor heat exchanger 12 used in an air-cooled chilling unit is, for example, a parallel-flow heat exchanger with corrugated fins. Parallel-flow heat exchangers are also called PFC heat exchangers or parallel-flow condensers. The wavy portions of the corrugated fins tend to form a liquid junction, a state in which water is retained. In this case, too, even if the outdoor heat exchanger 12 has the characteristic of being prone to a liquid junction, performing a drying operation causes the sprayed water to dry out, preventing the liquid junction from continuing.

[0050] Furthermore, the outdoor heat exchanger 12 is an all-aluminum air heat exchanger, that is, is made of aluminum, but because a liquid junction state does not continue during dry operation, corrosion is unlikely to occur in the outdoor heat exchanger 12. This prevents the progression of corrosion in the outdoor heat exchanger 12 from accelerating and causing refrigerant leakage from corroded areas.

[0051] <Modification> Fig. 10 is a flowchart illustrating the processing of the drying operation of the refrigeration cycle apparatus 100 according to a modification of embodiment 1. The modification of embodiment 1 differs from embodiment 1 in that the control device 3 controls the opening and closing of the injection valve 19 after the sprinkler operation ends. In the modification of embodiment 1, parts that are common to embodiment 1 are assigned the same reference numerals and description thereof will be omitted, and the description will focus on the differences from embodiment 1.

[0052] 10, after the process of step S11, the control device 3 proceeds to step S112. In step S112, the control device 3 determines whether the injection valve 19 is closed. If the control device 3 determines that the injection valve 19 is not closed (NO in step S112), the control device 3 proceeds to step S12 and starts the operation of the timer 6. On the other hand, if the control device 3 determines that the injection valve 19 is closed (YES in step S112), the control device 3 proceeds to step S113, opens the injection valve 19, proceeds to step S12, and starts the operation of the timer 6.

[0053] Next, the control device 3 proceeds to step S13. If the timer 6 determines in step S13 that the second time T2 has elapsed (YES in step S13), the control device 3 proceeds to step S114. In step S114, the control device 3 stops the operation of the compressor 10 and closes the injection valve 19, and then proceeds to step S15.

[0054] Next, the control device 3 proceeds to step S16, where it stops the operation of the outdoor fan 16, and the process ends.

[0055] In the first embodiment, the outlet water temperature rises temporarily immediately after the end of the water sprinkler operation, but then continues to fall until the operation of the compressor 10 stops, that is, until the second time T2 has elapsed. This is because when the water sprinkler operation ends, the compressor 10 is operating during the drying operation, and so low-pressure gas and water exchange heat in the water heat exchanger 14, which functions as an evaporator, causing the water temperature to fall.

[0056] As in the modified example, while the compressor 10 continues to operate, the injection valve 19 is kept open, so that the refrigerant flows through the injection circuit B, and the amount of refrigerant circulating in the water heat exchanger 14, which serves as an evaporator, is reduced. This prevents a decrease in the outlet temperature of the water heat exchanger 14.

[0057] Fig. 11 is a time chart for controlling the refrigeration cycle apparatus 100 according to a modified example of embodiment 1. In Fig. 11, the relationship between the amount of sprinkled liquid adhered and the outlet water temperature is shown by a solid line for embodiment 1, a dashed line for the modified example of embodiment 1, and a dashed line for the comparative example.

[0058] 11 , after the water sprinkler operation ends, injection circuit B is turned ON and refrigerant flows through injection circuit B until second time T2 has elapsed. By having some of the refrigerant from main circuit A flow through injection circuit B, the amount of refrigerant circulating in water heat exchanger 14, which serves as an evaporator, is reduced. This reduces the amount of heat exchanged in water heat exchanger 14, and the outlet water temperature rises compared to the first embodiment, as indicated by the open arrow, preventing a decrease in the outlet water temperature, which is the temperature of the water flowing out of water heat exchanger 14.

[0059] <Changes in inlet water temperature and outlet water temperature in water heat exchanger 14> Figure 12 is a graph showing changes in the inlet water temperature and outlet water temperature in the water heat exchanger 14 when cooling operation is being performed in the refrigeration cycle apparatus 100 according to embodiment 1. In Figure 12, the dotted line indicates the inlet water temperature, and the solid line indicates the outlet water temperature. As shown in Figure 12, when cooling operation is being performed, that is, when the compressor 10 and the outdoor fan 16 are operating, the inlet water temperature, which is the temperature of the water flowing into the water heat exchanger 14, and the outlet water temperature, which is the temperature of the water flowing out of the water heat exchanger 14, are both constant.

[0060] The heat balance of the water in the water heat exchanger 14 can be expressed as follows:

[0061] [Equation 1] Q ｃ = m × C ｐ ×ΔT

[0062] Here, Q ｃ is the amount of heat transferred from the water to the refrigerant by the water heat exchanger 14; m is the water flow rate; C ｐ is the specific heat of water. ΔT is the water outlet temperature T ｗｏｕｔ and the water inlet temperature T ｗｉｎ The temperature difference between the water inlet temperature T ｗｉｎ -Water outlet temperature T ｗｏｕｔ is.

[0063] The heat balance of the refrigerant in the water heat exchanger 14 is expressed as follows: [Equation 2] Q ｃ '=G ｒ ×Δh

[0064] Here, Q ｃ ' is the amount of heat that the refrigerant removes from the water by the water heat exchanger 14. G ｒ is the amount of refrigerant circulating, and is a value proportional to the frequency of the compressor 10. Δh is the difference between the enthalpy of the refrigerant at the outlet and the enthalpy of the refrigerant at the inlet, ie, refrigerant outlet enthalpy - refrigerant inlet enthalpy.

[0065] In the heat balance between the refrigerant and water, the following relationship holds:

[0066] [Equation 3] Q ｃ =Q ｃ '

[0067] When the water heat exchanger 14 is performing a cooling operation, the frequency of the compressor 10 is automatically adjusted so that the outlet water temperature becomes the water temperature required by the user, and therefore the outlet water temperature is constant. The water flow rate and the specific heat of water are constant. Δh also changes depending on the frequency of the compressor 10. The water flowing out of the water heat exchanger 14 is heated in the heat source device used by the user and returns to the water heat exchanger 14, so the inlet water temperature is generally constant. Therefore, the following relationship holds:

[0068] [Equation 4] m×C ｐ × (T ｗｉｎ -T ｗｏｕｔ ) = G ｒ ×Δh

[0069] The heat source unit is generally a fan coil unit made up of a heat exchanger, a fan motor unit, and an air filter.

[0070] Fig. 13 is a graph showing changes in the inlet water temperature and the outlet water temperature in the water heat exchanger 14 when the cooling operation is stopped in the refrigeration cycle apparatus 100 according to Embodiment 1. As shown in Fig. 13, when the cooling operation is stopped, that is, when the compressor 10 and the outdoor fan 16 are stopped, the inlet water temperature gradually decreases, while the outlet water temperature gradually increases, until the inlet water temperature and the outlet water temperature become equal.

[0071] When the cooling operation is stopped, the compressor 10 stops and the frequency of the compressor 10 becomes zero, so the refrigerant circulation amount G ｒ becomes zero, and no heat exchange occurs in the water heat exchanger 14. Therefore, the outlet water temperature becomes the inlet water temperature. Also, since the heat source machine being used on the user side is stopped and the water flowing out of the water heat exchanger 14 returns to the water heat exchanger 14 without being heated, the inlet water temperature is the outlet water temperature. Therefore, the following relationship holds:

[0072] [Equation 5] m × C ｐ × (T ｗｉｎ -T ｗｏｕｔ ) = 0 × Δh

[0073] 14 is a graph showing changes in the inlet water temperature and the outlet water temperature in the water heat exchanger 14 when the drying operation is performed after the cooling operation is stopped in the refrigeration cycle apparatus 100 according to Embodiment 1. As shown in FIG. 14 , when the drying operation is started after the cooling operation is stopped, both the inlet water temperature and the outlet water temperature decrease.

[0074] During the drying operation, the compressor 10 continues to operate, and the refrigerant circulation amount G ｒ does not become zero, heat exchange occurs in the water heat exchanger 14, and the outlet water temperature decreases. Also, since the heat source device used by the user is stopped and the water flowing out of the water heat exchanger 14 returns to the water heat exchanger 14 without being heated, the inlet water temperature is the outlet water temperature. Therefore, both the inlet water temperature and the outlet water temperature decrease. Therefore, the following relationship holds:

[0075] [Equation 6] m × C ｐ × (T ｗｉｎ -T ｗｏｕｔ ) = G ｒ ×Δh

[0076] The relationship when the drying operation is performed is the same as when the cooling operation is performed, except that the inlet water temperature decreases together with the outlet water temperature. Note that during the drying operation, the water temperature temporarily rises immediately after the cooling operation is stopped, but this is due to the slowdown of the frequency of the compressor 10.

[0077] Fig. 15 is a graph showing changes in the inlet water temperature and outlet water temperature in the water heat exchanger 14 when the drying operation is performed after the cooling operation is stopped in the refrigeration cycle apparatus 100 according to the comparative example of embodiment 1. As shown in Fig. 15, when the drying operation is started after the cooling operation is stopped and the injection circuit B is turned on, the inlet water temperature and outlet water temperature decrease, but the rate of decrease is slower than in the case of embodiment 1. In this case, the following relationship holds:

[0078] [Equation 7] m×C ｐ × (T ｗｉｎ -T ｗｏｕｔ ) = G ｒ '×Δh

[0079] Here, T ｗｉｎdecreases in accordance with the decrease in the outlet water temperature. In this way, after the cooling operation is stopped, the drying operation is started and the injection circuit B is turned on, so that the decrease in the outlet water temperature during the drying operation can be suppressed.

[0080] As described above, the refrigeration cycle apparatus 100 according to the first embodiment is configured to continue operation of the outdoor fan 16 after the sprinkler operation by the sprinkler device 5 is completed. This forcibly generates convection in the air around the outdoor heat exchanger 12, shortening the time it takes for the outdoor heat exchanger 12 to dry and shortening the time that the water sprayed by the sprinkler device 5 remains on the outdoor heat exchanger 12, thereby suppressing corrosion of the outdoor heat exchanger 12.

[0081] In addition, the control device 3 continues operating the outdoor fan 16 until the first time T1, for example, one hour, has elapsed after the sprinkler operation has ended, thereby shortening the time that the sprinkler liquid from the sprinkler device 5 remains attached to the outdoor heat exchanger 12 and suppressing corrosion of the outdoor heat exchanger 12.

[0082] Furthermore, after the end of the sprinkling operation, the control device 3 continues operating the compressor 10 for a second time T2 that is shorter than the first time T1, so that high-temperature gas refrigerant flows into the outdoor heat exchanger 12 and supplies heat to the sprinkling liquid. This further shortens the time it takes for the outdoor heat exchanger 12 to dry, and corrosion of the outdoor heat exchanger 12 can be suppressed.

[0083] Furthermore, the control device 3 keeps the injection valve 19 open until the second time T2 has elapsed after the end of the water spray operation, so that the refrigerant flows into the injection circuit B, and the amount of refrigerant circulating in the water heat exchanger 14, which serves as an evaporator, is reduced. This makes it possible to suppress a decrease in the outlet temperature of the water heat exchanger 14.

[0084] Furthermore, the control device 3 terminates the sprinkling operation of the sprinkler device 5 at the same time as the end of the operation of generating chilled water by the water heat exchanger. This reduces the condensation temperature in the outdoor heat exchanger 12, suppresses the motor output of the compressor 10, and reduces the amount of water sprinkled by the sprinkler device 5.

[0085] Embodiment 2. Fig. 16 is a flowchart illustrating the processing of the drying operation in the refrigeration cycle apparatus 100 according to embodiment 2. Embodiment 2 differs from embodiment 1 in that the water sprinkling operation ends before the cooling operation ends. In embodiment 2, parts that are common to embodiment 1 are assigned the same reference numerals and description thereof will be omitted, and the description will focus on the differences from embodiment 1.

[0086] As shown in Fig. 16, in step S11, the control device 3 determines whether the sprinkler operation by the sprinkler device 5 has ended. If the sprinkler operation by the sprinkler device 5 has ended, the control device 3 executes the drying operation. At this time, the cooling operation for producing cold water has not ended. If the control device 3 determines in step S11 that the sprinkler operation by the sprinkler device 5 has ended (YES in step S11), the control device 3 proceeds to step S12, starts the operation of the timer 6, and proceeds to step S13. If the control device 3 determines in S13 that the time measured by the timer 6 has reached the second time T2 (YES in step S13), the control device 3 proceeds to step S131.

[0087] In step S131, the control device 3 determines whether the cooling operation for producing chilled water has stopped. If the control device 3 determines in step S131 that the cooling operation has stopped (YES in step S131), the control device 3 proceeds to step S114, where it stops the operation of the compressor 10 and closes the injection valve 19, and proceeds to step S15. On the other hand, if the control device 3 determines in step S131 that the cooling operation has not stopped (NO in step S131), it proceeds to step S15 without going through step S114. In other words, if the cooling operation continues even after the time measured by the timer 6 has elapsed the second time T2, which is a time set depending on the installation environment, the process of step S114 as the drying operation is not performed. Note that step S114 may be omitted and step S14 of FIG. 10 may be performed, i.e., the process of stopping the operation of the compressor 10 without operating the injection valve 19.

[0088] If the control device 3 determines in step S15 that the time measured by the timer 6 has reached the first time T1, the process proceeds to step S132, where it determines whether the cooling operation that produces chilled water has stopped. If the control device 3 determines in step S132 that the cooling operation has stopped (YES in step S132), the process proceeds to step S16, where it stops the operation of the outdoor fan 16 and ends the process. If the control device 3 determines in step S132 that the cooling operation has not stopped (NO in step S132), the process ends without going through step S16. In other words, if the cooling operation continues even after the time measured by the timer 6 has passed the first time T1, which is a time set depending on the installation environment, the drying operation is not performed.

[0089] During cooling operation, the compressor 10 and the motor of the outdoor fan 16 are in operation, so if cooling operation is continued after the water spray operation is completed, an operation equivalent to drying operation is realized. Therefore, if cooling operation is continued after the water spray operation is completed, corrosion can be suppressed while shortening the time required for the outdoor heat exchanger 12 to dry, or without performing the drying operation.

[0090] Fig. 17 is a time chart for controlling the refrigeration cycle apparatus 100 according to embodiment 2. In Fig. 17, the relationship between the amount of spray liquid adhered and the outlet water temperature is shown by a solid line for embodiment 1, a dashed line for the modified example of embodiment 1, a two-dot chain line for embodiment 2, and a dashed line for the comparative example.

[0091] As shown in FIG. 17 , in the second embodiment, the cooling operation continues even after the timer 6 starts measuring time after the water spray operation ends, for example, until the third time T3 has elapsed. If the cooling operation continues after the water spray operation ends, the compressor 10 and the outdoor fan 16 continue to operate, resulting in a state similar to that of the drying operation, and the sprayed water in the outdoor heat exchanger 12 dries. In this way, the timer 6 starts measuring time after the water spray operation ends, and the cooling operation continues, thereby preventing unnecessary drying operations. Furthermore, as the cooling operation continues, the outlet water temperature rises, as indicated by the open arrow, and the decrease in the outlet water temperature during the drying operation can be further prevented than in the modified example of the first embodiment.

[0092] As described above, in the refrigeration cycle apparatus 100 according to the second embodiment, the cooling operation continues even after the sprinkler operation ends. During the cooling operation, the compressor 10 and the motor of the outdoor fan 16 are in operation. Therefore, by ending the sprinkler operation before the cooling operation ends, an operation equivalent to the drying operation is achieved. This further shortens the time required for the outdoor heat exchanger 12 to dry, and corrosion of the outdoor heat exchanger 12 can be suppressed.

[0093] 1 Internal heat exchanger, 1a First flow path, 1b Second flow path, 3 Control device, 5 Sprinkler device, 6 Timer, 7 Memory, 8 CPU, 10 Compressor, 11 Four-way valve, 12 Outdoor heat exchanger, 13 Expansion valve, 14 Water heat exchanger, 14a Refrigerant flow path, 14b Water flow path, 15 Accumulator, 16 Outdoor fan, 17 Condensation temperature detection means, 19 Injection valve, 21 Indoor flow rate adjustment device, 23 Indoor fan, 50 Pump, 50a First piping, 50b Second piping, 51a First nozzle, 51b Second nozzle, 52 Connecting piping, 100 Refrigeration cycle device, 120 Heat exchange section, 121 Heat transfer tube, 122 Fin, 123 Header, A Main circuit, B Injection circuit.

Claims

1. a condenser through which a refrigerant flows; A blower that blows air to the condenser; A water sprinkler for sprinkling water on the condenser; A control device that continues the operation of the blower after the sprinkler has finished sprinkling water; a compressor that compresses the refrigerant flowing through the condenser; Equipped with The control device includes: After the sprinkler has finished sprinkling water, the operation of the blower is continued until a first time has elapsed, and the operation of the compressor is continued until a second time that is shorter than the first time has elapsed. Refrigeration cycle equipment.

2. A throttle device for adjusting the pressure of the refrigerant; an evaporator for producing cold water by heat exchange between the refrigerant and water; a main circuit in which the condenser, the compressor, the throttling device, and the evaporator are connected by piping and in which the refrigerant circulates; an injection circuit for causing a portion of the refrigerant flowing from the condenser to the throttling device to flow into the compressor; an injection valve provided in the injection circuit; Further comprising: The control device includes: After the sprinkler has finished sprinkling, the injection valve is opened, and when the second time has elapsed, the injection valve is closed. The refrigeration cycle device according to claim 1.

3. The evaporator is a water heat exchanger that generates cold water by heat exchange between the refrigerant and water, The control device includes: The operation of producing cold water by the water heat exchanger is terminated at the same time as the end of the sprinkling by the sprinkler device. The refrigeration cycle device according to claim 2.

4. The evaporator is a water heat exchanger that generates cold water by heat exchange between the refrigerant and water, The control device includes: The operation of producing cold water by the water heat exchanger is continued even after the end of the water sprinkling by the water sprinkler. The refrigeration cycle device according to claim 2.