Refrigeration cycle equipment

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

[Technical Field]

[0001] This disclosure relates to a refrigeration cycle system that sprays water onto a condenser. [Background technology]

[0002] In refrigeration cycle systems, it is known that when the outside air temperature is high, water is sprayed onto the air heat exchanger, which acts as a condenser in the outdoor unit, and the condenser is cooled by 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 having plate fins. In Patent Document 1, multiple spray nozzles are arranged in front of the heat exchanger, and a water spraying operation is performed in which mist-like water is sprayed when the heat exchanger is in cooling operation, functioning as a condenser. By performing the water spraying operation, the condensation temperature can be reduced and the output of the compressor motor can be limited. After the water spraying operation is completed, the compressor and fan motor are stopped, and the sprayed liquid adhering to the heat exchanger dries naturally by heat conduction or radiant heat absorption from the surrounding air or the heat exchanger material in contact with the sprayed liquid. The water used for water spraying is generally tap water. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 5880019 [Overview of the project] [Problems that the invention aims to solve]

[0005] As in the case of Patent Document 1, the water used for watering is tap water, which contains metal ions, and if it adheres to an aluminum air heat exchanger, corrosion will occur. If the water is dried naturally after watering by heat conduction or radiant heat absorption from the surrounding air or the heat exchanger material in contact with the water, it takes time to dry, and the water remains on the heat exchanger for an extended period, causing corrosion to progress.

[0006] The present disclosure aims to provide a refrigeration cycle device that can suppress the progression of corrosion when water is sprayed onto an air heat exchanger made of aluminum. [Means for solving the problem]

[0007] The refrigeration cycle device according to this disclosure comprises a condenser through which a refrigerant flows, a blower that blows air into the condenser, a water spraying device that sprays water onto the condenser, and a control device that continues the operation of the blower after the water spraying by the water spraying device is completed. The control device comprises a compressor for compressing the refrigerant flowing through the condenser, and the control device continues to operate the blower until a first time has elapsed after the watering by the watering device has finished, and continues to operate the compressor until a second time, which is shorter than the first time, has elapsed. It is. [Effects of the Invention]

[0008] According to the refrigeration cycle device described herein, since the blower continues to operate after the water spraying is finished, the time it takes for the water sprayed onto the air heat exchanger, which acts as a condenser, to dry is shortened due to the absorption of heat by the water sprayed through forced convection. As a result, the time the water sprayed onto the air heat exchanger is shortened, and corrosion of the air heat exchanger can be suppressed. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram of the refrigeration cycle device according to Embodiment 1. [Figure 2] This is a functional configuration diagram of the control device for the refrigeration cycle system according to Embodiment 1. [Figure 3] This is a schematic perspective view of the outdoor heat exchanger according to Embodiment 1. [Figure 4] This is a schematic diagram illustrating the watering device of a refrigeration cycle system according to Embodiment 1. [Figure 5] It is a schematic diagram explaining the principle of corrosion by tap water in an outdoor heat exchanger. [Figure 6] It is a schematic diagram explaining the principle of galvanic corrosion in an outdoor heat exchanger. [Figure 7] It is a flowchart explaining the process of the drying operation in the refrigeration cycle device according to Embodiment 1. [Figure 8] It is a time chart in the control of the refrigeration cycle device according to the comparative example. [Figure 9] It is a time chart in the control of the refrigeration cycle device according to Embodiment 1. [Figure 10] It is a flowchart explaining the process of the drying operation in the refrigeration cycle device according to a modified example of Embodiment 1. [Figure 11] It is a time chart in the control of the refrigeration cycle device according to a modified example of Embodiment 1. [Figure 12] It is a graph showing the transition of the inlet water temperature and the outlet water temperature in the water heat exchanger when the cooling operation is being performed in the refrigeration cycle device according to Embodiment 1. [Figure 13] It is a graph showing the transition of the inlet water temperature and the outlet water temperature in the water heat exchanger when the cooling operation stops in the refrigeration cycle device according to Embodiment 1. [Figure 14] It is a graph showing the transition of the inlet water temperature and the outlet water temperature in the water heat exchanger when the drying operation is performed after the cooling operation stops in the refrigeration cycle device according to Embodiment 1. [Figure 15] It is a graph showing the transition of the inlet water temperature and the outlet water temperature in the water heat exchanger when the drying operation is performed after the cooling operation stops in the refrigeration cycle device according to the comparative example of Embodiment 1. [Figure 16] It is a flowchart explaining the process of the drying operation in the refrigeration cycle device according to Embodiment 2. [Figure 17] It is a time chart in the control of the refrigeration cycle device according to Embodiment 2.

Mode for Carrying Out the Invention

[0010] Embodiments of this disclosure will be described below with reference to the drawings. However, this disclosure is not limited to the embodiments described below. Also, the relationships of the sizes of the components in the drawings below, including Figure 1, may differ from those in reality. Furthermore, in the following description, terms indicating direction will be used as appropriate to facilitate understanding of this disclosure, but these terms are for illustrative purposes only and do not limit this disclosure. Examples of terms indicating direction include "up," "down," "right," "left," "front," or "back."

[0011] Embodiment 1. <Configuration of the refrigeration cycle system> Figure 1 is a schematic diagram of the refrigeration cycle device 100 according to Embodiment 1. The refrigeration cycle device 100 of this Embodiment 1 is, for example, an air-cooled chilling unit that generates chilled water.

[0012] As shown in Figure 1, the refrigeration cycle device 100 is composed of a main circuit A and an injection circuit B. The main circuit A and injection circuit B are refrigerant circuits through which the refrigerant circulates. As the refrigerant, for example, single refrigerants such as R-22 and R-134a, pseudo-azeotropic mixed refrigerants such as R-410A and R-404A, or non-azeotropic mixed refrigerants such as R-407C can be used. In addition, as the refrigerant, refrigerants with a relatively low global warming potential, such as CF3CF=CH2, which contain a double bond in their chemical formula, or mixtures thereof, or natural refrigerants such as CO2 or propane can be used.

[0013] <Configuration of Main Circuit A> 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 inhaled refrigerant. The compressor 10 is driven via a compressor inverter drive device (not shown) or the like. Based on instructions from the control device 3, the compressor 10 can change its capacity, which is the amount of refrigerant delivered per unit time, by arbitrarily changing the drive frequency. A condensation temperature detection means 17 is provided between the compressor 10 and the outdoor heat exchanger 12 to detect the condensation temperature of the refrigerant discharged from the compressor 10. The condensation temperature detection means 17 is, for example, a pressure sensor. The control device 3 calculates the condensation temperature by converting the pressure value detected by the condensation temperature detection means 17 to the saturation temperature.

[0014] The outdoor heat exchanger 12 is an air heat exchanger that performs heat exchange between the refrigerant and the outside air. In the cooling operation to cool water, the outdoor heat exchanger 12 functions as a condenser, performing heat exchange between the high-pressure refrigerant flowing in from the compressor 10 side and the air, condensing and liquefying the refrigerant.

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

[0016] Furthermore, the outdoor fan 16 supplies air to the outdoor heat exchanger 12, promoting heat exchange between the refrigerant and the air. Here, the outdoor fan 16 is driven via a fan inverter drive device (not shown) or the like. The airflow of the outdoor fan 16 can be changed by arbitrarily changing the drive frequency based on instructions from the control device 3. The outdoor fan 16 corresponds, for example, on a one-to-one basis with the outdoor heat exchanger 12. The correspondence between the outdoor fan 16 and the outdoor heat exchanger 12 is not limited to this. Note that the outdoor fan 16 is an example of a blower.

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

[0018] The water heat exchanger 14, which acts as a heat transfer medium heat exchanger, performs heat exchange between the water, which is the heat transfer medium, and the refrigerant. The water heat exchanger 14 has a refrigerant flow path 14a through which the refrigerant of the main circuit A circulates and a water flow path 14b through which the water, which is the heat transfer medium, circulates. During cooling operation, the water heat exchanger 14 functions as an evaporator, performing heat exchange between the refrigerant flowing in from the expansion valve 13 side and the water, evaporating and vaporizing the refrigerant, and cooling the water.

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

[0020] Each accumulator 15 is located on the suction side of the compressor 10 and stores excess refrigerant in the refrigerant circuit.

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

[0022] The injection valve 19 expands and depressurizes the refrigerant flowing through the injection circuit B, which is branched from the main circuit A. Similar to the expansion valve 13, the injection valve 19 is an electronic expansion valve that changes its opening degree based on instructions from the control device 3, for example. Note that the refrigeration cycle device 100 may also be configured without the injection circuit B.

[0023] <Configuration of control device 3> Figure 2 is a functional configuration diagram of the control device 3 of the refrigeration cycle device 100 according to Embodiment 1. As shown in Figure 2, the control device 3 comprises a memory 7, a CPU 8, and a timer 6. The control device 3 controls the operation of the entire refrigeration cycle device 100. The control device 3 is composed of a computer equipped with the memory 7 and CPU 8, dedicated hardware such as an ASIC or FPGA, or both. The memory 7 stores the 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 device 100 based on detection information such as temperature sensors or pressure sensors equipped in the refrigeration cycle device 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, and the water spraying of the water spraying device 5.

[0024] <Configuration of the outdoor heat exchanger 12> Figure 3 is a schematic perspective view of an outdoor heat exchanger 12 according to Embodiment 1. As shown in Figure 3, the outdoor heat exchanger 12 comprises a heat exchange section 120 consisting of 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 a 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 easier to process than copper because it is easy to manufacture heat exchangers with micro or mini channels such as flat tubes, and it is also cheaper than copper. By using aluminum for the outdoor heat exchanger 12, it is possible to make the outdoor heat exchanger 12 smaller, lighter, more efficient, and reduce its internal volume, i.e., reduce the amount of refrigerant used. Reducing the amount of refrigerant makes it possible to address environmental issues.

[0026] The heat transfer tube 121 is a flattened tube with multiple flow channels formed inside. Each heat transfer tube 121 is positioned extending between a pair of headers 123. Each heat transfer tube 121 is spaced apart from each other in a direction perpendicular to the direction of extension. The direction of extension of each heat transfer tube 121 is, for example, the horizontal direction. The pair of headers 123 are positioned vertically, perpendicular to the direction of extension 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 shape. Each fin 122 is positioned extending between a pair of headers 123. Each fin 122 is positioned between two adjacent heat transfer tubes 121 of a plurality of heat transfer tubes 121, and the two adjacent heat transfer tubes 121 are connected by the fin 122.

[0028] <Configuration of the sprinkler system 5> Figure 4 is a schematic diagram illustrating the sprinkler device 5 of the refrigeration cycle device 100 according to Embodiment 1. As shown in Figure 4, the sprinkler device 5 includes, for example, a first pipe 50a, a second pipe 50b, and connecting pipes 52 connected to the first pipe 50a and the second pipe 50b, respectively. The sprinkler device 5 sprays water onto the outdoor heat exchanger 12, which is an air heat exchanger. This lowers the condensation temperature in the outdoor heat exchanger 12, suppressing the output of the motor in the compressor 10.

[0029] The watering device 5 is attached, for example, to a housing that holds the outdoor heat exchanger 12. The watering device 5 and the outdoor heat exchanger 12 are spaced apart in the depth direction. The watering device 5 performs watering operation under the control of the control device 3. Watering operation promotes an improvement in 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 each pipe is connected to a connecting pipe 52. The connecting pipe 52 is connected to a water pipe or the like. Water flowing in from the connecting pipe 52 is supplied to the first pipe 50a and the second pipe 50b, respectively. The connecting pipe 52 is equipped with a valve (not shown) for adjusting the water flow rate. The control device 3 controls the valve of the sprinkler system 5, thereby controlling the start, stop, and amount of water sprayed by the sprinkler system 5.

[0031] The first pipe 50a and the second pipe 50b are arranged facing each other. The first pipe 50a is arranged extending vertically outside one horizontal end of the heat exchange section 120. The second pipe 50b is arranged extending vertically outside the other horizontal end of the heat exchange section 120.

[0032] The first pipe 50a is provided with a plurality of first nozzles 51a. For example, the first pipe 50a is provided with five first nozzles 51a. The number of first nozzles 51a may be four or fewer, or six or more. Each first nozzle 51a is a hollow conical nozzle that sprays mist-like water at a spray angle of 60°. Each first nozzle 51a is arranged at vertical intervals and sprays water toward the heat exchange section 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, the second pipe 50b is provided with five second nozzles 51b. The number of second nozzles 51b may be four or fewer, or six or more. Each second nozzle 51b is a hollow conical nozzle that sprays mist-like water at a spray angle of 60°, for example. Each second nozzle 51b is arranged at vertical intervals and sprays water toward the heat exchange section 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 watering operation by the watering device 5 is controlled by the control device 3. For example, when the cooling operation in which chilled water is generated in the water heat exchanger 14 is completed, the control device 3 starts the watering operation by the watering device 5.

[0035] <Principles 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 remains in contact with aluminum material for an extended period, the aluminum material will corrode. Tap water generally contains metal ions. When tap water comes into contact with 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 dissolves. This reaction is called a substitution reaction. If tap water used for watering remains in contact with the outdoor heat exchanger 12, which uses aluminum material, a substitution reaction will occur in the outdoor heat exchanger 12.

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

[0037] <Drying operation> Figure 7 is a flowchart illustrating the drying operation process in the refrigeration cycle device 100 according to Embodiment 1. As shown in Figure 7, in step S11, the control device 3 determines whether or not the watering operation by the watering device 5 has finished. When the cooling operation that generates chilled water is finished, the control device 3 simultaneously terminates the watering operation by the watering device 5 and performs the drying operation. In step S11, if the control device 3 determines that the watering operation by the watering device 5 has not finished (NO in step S11), it repeats the process, and if it determines that it has finished (YES in step S11), it proceeds to step S12.

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

[0039] In step S14, the control device 3 stops the operation of the compressor 10 and 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. For example, the first time T1 is 1 hour. For example, the second time T2 is 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 process is repeated. 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 process proceeds to step S16.

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

[0042] In the drying operation, after the water spraying is finished, the fan motor of the outdoor fan 16 continues to operate for a certain period of time, for example, the first hour T1. This forces convection into the air surrounding 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] Furthermore, after the water spraying is completed, the compressor 10 continues to operate for a certain period of time, for example, the second hour T2. This allows the high-temperature gaseous refrigerant to flow into the outdoor heat exchanger 12, which is an air heat exchanger, supplying heat to the sprayed water. This further shortens the time it takes for the outdoor heat exchanger 12 to dry, preventing corrosion of the outdoor heat exchanger 12.

[0044] Furthermore, the control device 3 may control the fan motor of the outdoor fan 16 to continue operation for a first time T1 after the water spraying operation is completed, and the compressor 10 to stop operation simultaneously with the completion of the water spraying operation. The first time T1 and the second time T2 may be set according to the conditions of the environment or installation location where the outdoor heat exchanger 12 is installed.

[0045] <Comparative Example> Figure 8 is a time chart for the control of the refrigeration cycle device 100 according to the comparative example. The vertical axis of Figure 8 shows the On / Off state and the drying state, and the horizontal axis shows time. As shown in Figure 8, when the water spraying operation of the refrigeration cycle device 100 according to the comparative example is completed, the fan motors of the compressor 10 and the outdoor fan 16 simultaneously stop. The drying time for the air heat exchanger is from the time T0 when the water spraying operation is completed until time Td1. In this case, since the water sprayed onto the air heat exchanger dries naturally, the state in which water is retained on the air heat exchanger continues.

[0046] <Effects of drying operation> Figure 9 is a time chart for the control of the refrigeration cycle device 100 according to Embodiment 1. In Figure 9, the vertical axis shows the On / Off state and the drying state, and the horizontal axis shows time. Also in Figure 9, the relationship between the amount of spray liquid adhering and the outlet water temperature is shown by a solid line for Embodiment 1 and by a dashed line for the comparative example. The outlet water temperature is the temperature of the water flowing out from the water heat exchanger 14.

[0047] As shown in Figure 9, in Embodiment 1, when a time Td2 has elapsed from time T0, when the watering operation has ended, which is shorter than time Td1, the amount of water adhering to the surface becomes zero. By continuing to operate the compressor 10 and the outdoor fan 16 after the watering operation has ended, the reduction in the amount of water adhering to the surface is accelerated, and the drying time until the surface becomes dry after the watering operation has ended is shortened from time Td1 to time Td2.

[0048] If the air heat exchanger is designed with copper tubing, even if it is subjected to watering, a displacement reaction like that seen with aluminum will not occur. Furthermore, if the air heat exchanger is a finned-tube type, even if it is subjected to watering, water is less likely to remain between the fins and tubes, so corrosion is less likely to occur even if water remains in the air heat exchanger for an extended period.

[0049] On the other hand, the outdoor heat exchanger 12 used in the air-cooled chilling unit is, for example, a parallel flow type heat exchanger with corrugated fins. A parallel flow type heat exchanger is also called a PFC heat exchanger or Parallel Flow Condenser. The wavy parts of the corrugated fins are prone to a liquid junction state in which water is retained. Even in this case, when a drying operation is performed, the sprayed water dries up, and the liquid junction state does not persist, even if the outdoor heat exchanger 12 has a characteristic of being prone to a liquid junction state.

[0050] Furthermore, although the outdoor heat exchanger 12 is an all-aluminum air heat exchanger, meaning it is made of aluminum, corrosion is less likely to occur in the outdoor heat exchanger 12 because the liquid junction condition is not maintained during dry operation. Therefore, it is possible to prevent the progression of corrosion in the outdoor heat exchanger 12 from being accelerated and the refrigerant from leaking from corroded areas.

[0051] <Variation> Figure 10 is a flowchart illustrating the drying operation process of the refrigeration cycle device 100 according to a modified example of Embodiment 1. The modified example 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 water spraying operation is completed. In the modified example of Embodiment 1, parts common to Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted, and the explanation will focus on the differences from Embodiment 1.

[0052] As shown in Figure 10, after processing in step S11, the control device 3 proceeds to step S112. In step S112, the control device 3 determines whether the injection valve 19 is in a closed state or not. If it determines that it is not in a closed state (NO in step S112), it proceeds to step S12 and starts the operation of the timer 6. On the other hand, if the control device 3 determines in step S112 that the injection valve 19 is in a closed state (YES in step S112), it 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. In step S13, if the timer 6 determines that the second time T2 has elapsed (YES in step S13), it proceeds to step S114. In step S114, the control device 3 stops the operation of the compressor 10, closes the injection valve 19, and proceeds to step S15.

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

[0055] In Embodiment 1, the outlet water temperature temporarily rises immediately after the water spraying operation ends, but then continues to decrease until the compressor 10 stops operating, that is, until the second time T2 has elapsed. This is because, when the water spraying operation ends, the compressor 10 is operating during the drying operation, and the low-pressure gas and water exchange heat in the water heat exchanger 14, which is functioning as an evaporator, cause the water temperature to decrease.

[0056] As shown in the modified example, by keeping the injection valve 19 open while the compressor 10 is running, refrigerant flows into the injection circuit B, reducing the amount of refrigerant circulating into the water heat exchanger 14, which acts as an evaporator. This suppresses the decrease in the outlet temperature of the water heat exchanger 14.

[0057] Figure 11 is a time chart for the control of a refrigeration cycle device 100 according to a modified example of Embodiment 1. In Figure 11, the relationship between the amount of spray liquid adhering and the outlet water temperature is shown by a solid line for Embodiment 1, a dashed line for a modified example of Embodiment 1, and a dashed line for a comparative example.

[0058] As shown in Figure 11, after the water spraying operation ends, the injection circuit B remains ON until the second time T2 has elapsed, allowing refrigerant to flow through the injection circuit B. The flow of a portion of the refrigerant from the main circuit A through the injection circuit B reduces the amount of refrigerant circulating into the water heat exchanger 14, which acts as an evaporator. This reduces the amount of heat exchanged in the water heat exchanger 14, causing the outlet water temperature to rise compared to Embodiment 1, as indicated by the white arrows, thus preventing a decrease in the outlet water temperature, which is the temperature of the water flowing out of the water heat exchanger 14.

[0059] <Changes in inlet and outlet water temperature in the water heat exchanger 14> Figure 12 is a graph showing the changes in the inlet water temperature and outlet water temperature in the water heat exchanger 14 when the refrigeration cycle device 100 according to Embodiment 1 is in cooling operation. In Figure 12, the dotted line represents the inlet water temperature, and the solid line represents the outlet water temperature. As shown in Figure 12, when the cooling operation is in progress, that is, when the compressor 10 and the outdoor fan 16 are operating, both 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 constant.

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

[0061] [Mathematics 1] Q c = m × C p ×ΔT

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

[0063] Furthermore, the heat balance of the refrigerant in the water heat exchanger 14 is expressed as follows. [Number 2] Q c ’ = G r ×Δh

[0064] Here, Q c ’ is the amount of heat taken away from water by the refrigerant by the heat exchanger 14. G r is the refrigerant circulation amount, which 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, which is refrigerant outlet enthalpy - refrigerant inlet enthalpy. [[ID=|16]]

[0065] And in the heat balance between the refrigerant and water, the following relationship holds.

[0066] [Number 3] Q c = Q c ’

[0067] In the heat exchanger 14, when the cooling operation is being performed, the frequency of the compressor 10 is automatically adjusted so that the outlet water temperature becomes the water temperature required by the user, so the outlet water temperature becomes constant. Also, the water flow rate and the specific heat of water are constant values. Also, Δh changes according to the frequency of the compressor 10. Also, the water flowing out of the heat exchanger 14 is heated in the heat source machine used on the user side and returns to the heat exchanger 14, so the inlet water temperature is generally constant. Therefore, the following relationship holds.

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

[0069] Note that the heat source machine is generally a fan coil unit composed of a heat exchanger, a fan motor unit, and an air filter.

[0070] Figure 13 is a graph showing the changes in the inlet water temperature and outlet water temperature in the water heat exchanger 14 when the cooling operation is stopped in the refrigeration cycle device 100 according to Embodiment 1. As shown in Figure 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 stops, the compressor 10 stops and the frequency of the compressor 10 becomes zero, so the refrigerant circulation amount G r The current also becomes zero, and no heat exchange occurs in the water heat exchanger 14. Therefore, the outlet water temperature becomes the inlet water temperature. Also, the heat source unit used by the user is stopped, and the water that flows out of the water heat exchanger 14 returns to the water heat exchanger 14 without being heated, so the inlet water temperature is the outlet water temperature. Therefore, the following relationship holds.

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

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

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

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

[0076] The relationship during drying operation is the same as that during cooling operation, except that the inlet water temperature decreases along with the outlet water temperature. Note that during drying operation, the water temperature temporarily rises immediately after the cooling operation stops, which is due to the reduction in the frequency of compressor 10.

[0077] Figure 15 is a graph showing the changes in the inlet and outlet water temperatures in the water heat exchanger 14 when a drying operation is performed after the cooling operation is stopped in the refrigeration cycle device 100 according to a comparative example of Embodiment 1. As shown in Figure 15, when the drying operation is started after the cooling operation is stopped and the injection circuit B is turned ON, the inlet and outlet water temperatures decrease, but the rate of decrease is reduced compared to the case of Embodiment 1. In this case, the following relationship holds.

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

[0079] Here, T win This decreases in accordance with the decrease in outlet water temperature. In this way, after the cooling operation is stopped, the drying operation is started and injection circuit B is turned on, which suppresses the decrease in outlet water temperature during the drying operation.

[0080] As described above, the refrigeration cycle device 100 according to Embodiment 1 is configured such that the outdoor fan 16 continues to operate after the watering operation by the watering device 5 has finished. This forces convection into the air surrounding the outdoor heat exchanger 12, shortening the time it takes for the outdoor heat exchanger 12 to dry, and reducing the time that the watering liquid from the watering device 5 remains on the outdoor heat exchanger 12, thereby suppressing corrosion of the outdoor heat exchanger 12.

[0081] Furthermore, since the control device 3 continues the operation of the outdoor fan 16 until a first time T1, for example 1 hour, has elapsed after the watering operation has finished, the time that the water sprayed by the watering device 5 adheres to the outdoor heat exchanger 12 is shortened, and corrosion of the outdoor heat exchanger 12 can be suppressed.

[0082] Furthermore, after the watering operation is completed, the control device 3 continues the operation of the compressor 10 for a second time T2, which is shorter than the first time T1. In this way, high-temperature gaseous refrigerant flows into the outdoor heat exchanger 12, supplying heat to the watering solution. As a result, the time required for the outdoor heat exchanger 12 to dry is further shortened, 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 water spraying operation has finished. As a result, refrigerant flows into the injection circuit B, and the amount of refrigerant circulating into the water heat exchanger 14, which acts as an evaporator, decreases. This helps to suppress the decrease in the outlet temperature of the water heat exchanger 14.

[0084] Furthermore, the control device 3 terminates the watering operation of the watering device 5 at the same time as the operation of chilled water generation by the water heat exchanger is completed. This lowers the condensation temperature in the outdoor heat exchanger 12, reduces the motor output of the compressor 10, and suppresses the amount of water used by the watering device 5.

[0085] Embodiment 2. Figure 16 is a flowchart illustrating the drying operation process in the refrigeration cycle device 100 according to Embodiment 2. Embodiment 2 differs from Embodiment 1 in that the water spraying operation is completed before the cooling operation is completed. In Embodiment 2, parts common to Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted, and the explanation will focus on the differences from Embodiment 1.

[0086] As shown in Figure 16, in step S11, the control device 3 determines whether the watering operation by the watering device 5 has finished. If the watering operation by the watering device 5 has finished, the control device 3 initiates the drying operation. At this time, the cooling operation that generates chilled water has not finished. In step S11, if the control device 3 determines that the watering operation by the watering device 5 has finished (YES in step S11), it proceeds to step S12, starts the operation of the timer 6, and proceeds to step S13. In S13, if the control device 3 determines that the time measured by the timer 6 has reached the second time T2 (YES in step S13), it proceeds to step S131.

[0087] In step S131, the control device 3 determines whether the cooling operation that generates chilled water has stopped. If the control device 3 determines in step S131 that the cooling operation has stopped (YES in step S131), it proceeds to step S114, stops the operation of the compressor 10, 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, which is the second time T2 set according to the installation environment, the process of step S114 as a drying operation is not performed. Alternatively, the process of stopping the operation of the compressor 10 without performing the process of step S114 may be performed, as shown in Figure 10, which is step S14 in Figure 10, i.e., without operating the injection valve 19.

[0088] In step S15, if the control device 3 determines that the time measured by the timer 6 has reached the first time T1, it proceeds to step S132 to determine whether the cooling operation that generates chilled water has stopped. In step S132, if the control device 3 determines that the cooling operation has stopped (YES in step S132), it proceeds to step S16, stops the operation of the outdoor fan 16, and the process ends. In step S132, if the control device 3 determines 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 elapsed to the first time T1, which is the time set according to the installation environment, the drying operation will not be performed.

[0089] During cooling operation, the motors of the compressor 10 and the outdoor fan 16 are operating. Therefore, if cooling operation continues after the water spraying operation has finished, the same operation as drying operation is achieved. Consequently, if cooling operation continues after the water spraying operation has finished, corrosion can be suppressed while shortening the time required for the outdoor heat exchanger 12 to dry, or without performing a drying operation.

[0090] Figure 17 is a time chart for the control of the refrigeration cycle device 100 according to Embodiment 2. In Figure 17, the relationship between the amount of spray liquid adhering and the outlet water temperature is shown by a solid line for Embodiment 1, a dashed line for a modified example of Embodiment 1, a double dashed line for Embodiment 2, and a dashed line for a comparative example.

[0091] As shown in Figure 17, in the second embodiment, even after the watering operation has finished and the timer 6 has started measuring time, the cooling operation continues until, for example, the third time T3 has elapsed. When the cooling operation continues after the watering operation has finished, the compressor 10 and the outdoor fan 16 continue to operate, creating a state similar to the drying operation, and the water sprayed on the outdoor heat exchanger 12 dries out. In this way, by starting the timer 6 to measure time after the watering operation has finished and continuing the cooling operation, the unnecessary drying operation can be suppressed. Furthermore, as indicated by the white arrows, the outlet water temperature rises due to the continuation of the cooling operation, which can further suppress the decrease in the outlet water temperature during the drying operation compared to the modified example of the first embodiment.

[0092] As described above, according to the refrigeration cycle device 100 of Embodiment 2, the cooling operation continues even after the water spraying operation is completed. During the cooling operation, the motors of the compressor 10 and the outdoor fan 16 are operating, so by ending the water spraying operation before the cooling operation is completed, operation equivalent to the drying operation can be achieved. This further shortens the time required for the outdoor heat exchanger 12 to dry, and corrosion in the outdoor heat exchanger 12 can be suppressed. [Explanation of symbols]

[0093] 1 Internal heat exchanger, 1a First flow path, 1b Second flow path, 3 Control device, 5 Sprayer, 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 Fins, 123 Header, A Main circuit, B Injection circuit.

Claims

1. A condenser through which the refrigerant flows, A blower that supplies air to the condenser, A watering device for spraying water onto the condenser, A control device that continues the operation of the blower after the watering by the watering device has finished, A compressor for compressing the refrigerant flowing through the condenser, Equipped with, The control device is After the watering by the watering device is completed, the operation of the blower is continued until a first hour has elapsed, and the operation of the compressor is continued until a second hour, which is shorter than the first hour, has elapsed. Refrigeration cycle device.

2. A throttling device for adjusting the pressure of the refrigerant, An evaporator that generates chilled water through heat exchange between the refrigerant and water, The condenser, the compressor, the throttling device, and the evaporator are connected by piping, and the refrigerant circulates through a main circuit. An injection circuit that directs a portion of the refrigerant flowing from the condenser to the throttle device into the compressor, An injection valve provided in the injection circuit, Furthermore, The control device is After the watering by the aforementioned watering device is completed, the injection valve is opened, and after the second time has elapsed, it is closed. The refrigeration cycle apparatus according to claim 1.

3. The evaporator is a water heat exchanger that generates chilled water through heat exchange between the refrigerant and water. The control device is Simultaneously with the termination of watering by the aforementioned sprinkler, the operation of generating chilled water by the aforementioned heat exchanger is terminated. The refrigeration cycle apparatus according to claim 2.

4. The evaporator is a water heat exchanger that generates chilled water through heat exchange between the refrigerant and water. The control device is Even after the watering by the aforementioned sprinkler system is completed, the operation of generating chilled water by the heat exchanger is continued. The refrigeration cycle apparatus according to claim 2.

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