Patent Application
20230392829
The present disclosure relates to a refrigerant circuit for cooling and/or heating purposes. In particular, the disclosure relates to a refrigerant circuit for a refrigeration apparatus with a thermal storage particularly a thermal storage with a phase changing material (PCM). Even more particular, the disclosure relates to a refrigerant circuit for a refrigeration apparatus with a thermal storage using CO2 as a refrigerant.
As described in EP 2 402 681 A1, conventionally, a refrigerating apparatus has been known, which includes a refrigerant circuit performing a refrigeration cycle. The refrigerating apparatus of this type has been widely used for coolers such as refrigerators and freezers for storing food etc. and air conditioners for cooling/heating an inside of a room.
Moreover, EP 2 844 924 B1 discloses an air-conditioning system comprising: a chiller system including a compressor, a condenser, an expansion device and an evaporator, a phase change material in thermal communication with the condenser, an actuator coupled to the phase change material; and a controller providing a trigger signal to the actuator to initiate changing the phase change material from a supercooled state to a solid state, wherein the phase change material includes a coolant supply line in thermal communication with the phase change material and the coolant supply line is coupled to the chiller system. The phase change material is selected so that the phase change material transitions from liquid to solid when cooling demand on the chiller system is low or non-existent. This may occur in the evening, when ambient temperatures are lower. During the day, the solid or frozen phase change material absorbs energy from the condenser, improving the efficiency of the condenser when the chiller system is running and increasing efficiency and capacity of the chiller system.
The air-conditioning system described in EP 2 844 924 B1 aims to provide a system that is capable of balancing cooling demand by using a phase change material as a heat buffer between the condenser and the ambient air temperature. During the day, the phase change material absorbs the heat from the condenser and release it to the outside air. Due to its thermal capacity and the latent heat release, the phase change material will heat up slower than air and thus result in higher energy efficiency. At night, the phase change material is cooled down faster by the fresher air temperature using the fan only.
However, active cooling of the phase change material with the fan is inefficient, therefore, said system is particularly not suitable for regions with warmer climates, where air temperatures at night remain high. Moreover, the described system is not able to realize big improvements with regard to energy efficiency but will “flatten out” the energy consumption pattern due to the thermal response time of the phase change material. This is in particular true, since the active cooling of the phase change material also causes heating of the condenser, as the condenser is in thermal communication with the phase change material, and no control of the use of the phase change material is possible.
Additionally, fluorocarbon has been conventionally used as a refrigerant in refrigeration systems. However, following the Montreal Protocol in 1987 and the Kyoto Protocol in 1997, artificially developed substitute chlorofluorocarbons, whose ozone depletion potential is low, have become commonly used as refrigerants. Yet, in recent years, the development of technology using even more environmentally friendly substitutes, particularly using natural refrigerants such as carbon dioxide, ammonia, hydrocarbons (isobutene, propane, etc.), water and air, has progressed. These natural refrigerants are materials that have the property that, when compared with the afore-mentioned chlorofluorocarbons and substitute chlorofluorocarbons, their GWP (Global Warming Potential) value is extremely low.
Among these, carbon dioxide is known as a material whose ozone depletion potential is zero, whose global warming potential is also much lower in comparison to conventional refrigerants, which has no toxicity, is non-flammable, and whose efficiency in creating a high temperature is good among natural refrigerants, and from environmental/energy aspects and safety aspects, carbon dioxide is garnering attention as a refrigerant in air conditioners.
However, carbon dioxide (CO2) performs at high outside temperatures with a lower efficiency than fluorinated refrigerants. Accordingly, on an annual base the performance of an air conditioner system using CO2 as a refrigerant is lower compared to fluorinated refrigerants, particularly in warmer climates.
In view of the above, there is the desire to provide a refrigerant circuit for a refrigeration apparatus with a thermal storage, which is using carbon dioxide (CO2) as refrigerant, allowing the storage of thermal energy, particularly cold, for example when outside temperatures are low, preferably during the night, and use the thermal energy during peak temperatures during the day when transcritical conditions occur or during peak demand, in order to substantially prevent a decrease in cooling efficiency, which is particularly due to the use of a natural refrigerant like carbon dioxide, while ensuring a high cooling capacity and providing flexibility with regard to charging the thermal storage with cold. Additionally, if circumstances require it or allow it, the provided refrigerant circuit should also be able to store thermal energy, particularly cold, even during peak temperatures when for example much/excess PV power (CO2 neutral energy generation) is available.
This aim may be achieved by a refrigerant circuit as defined in claim 1. Embodiments may be found in the dependent claims, the following description and the accompanying drawings.
According to a first aspect of present disclosure, a refrigerant circuit for a refrigeration apparatus with a thermal storage, which is using carbon dioxide (CO2) as refrigerant, includes: at least one compressor, a heat-source-side heat exchanger, an expansion device, and a thermal storage, including a thermal storage material, particularly a phase changing material (PCM) from the group: organic PCMs like bio-based, paraffin, carbohydrate or lipid derived, or water, wherein the refrigerant circuit further includes: a first fluid communication pipe communicating between a fluid side of the heat-source-side heat exchanger and one side of the thermal storage, and a second fluid communication pipe communicating between the expansion device and the other side of the thermal storage.
Hence, a refrigerant circuit is provided, capable of storing thermal energy, particularly cold, when for example outside temperatures are low, and using the stored thermal energy during peak temperatures during the day when transcritical conditions occur or during peak demand, in order to substantially prevent a decrease in cooling efficiency, which is particularly due to the use of a natural refrigerant like carbon dioxide, while ensuring a high cooling capacity and providing flexibility with regard to charging the thermal storage with cold. Additionally, the provided refrigerant circuit also allows to store thermal energy, particularly cold, during peak temperatures, if other circumstances require it or make it possible, like for example excess of PV (photovoltaic) power or other CO2 neutral generated electric power. Accordingly, the provided refrigerant circuit can not only store thermal energy when low outside temperatures allow it, but also by availability of excessive renewable electricity, which in total will decrease CO2 emissions even further, even if the refrigerant circuit is less efficient.
As regards the term “natural” concerning the “natural refrigerant”, the term defines in the present disclosure refrigerants that occur naturally.
Moreover, in the present disclosure the term “fluid” concerning the “fluid communication pipe(s)” and the “fluid port(s)” is used as the fluid, particularly the CO2, flowing there through is in a supercritical condition (supercritical fluid), which means, the fluid is at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist. Accordingly, the “fluid communication pipe(s)” and the “fluid port(s)” are common “liquid communication pipe(s)” and “liquid port(s)”, only emphasizing that the fluid flowing there through is in a supercritical condition.
According to a second aspect, the refrigerant circuit further includes a first switching mechanism located/provided on the first fluid communication pipe and communicating among the heat-source-side heat exchanger, the thermal storage, a third fluid communication pipe, and a first gas communication pipe, wherein the third fluid communication pipe communicates to the expansion device and the first gas communication pipe communicates to a suction side of the compressor.
According to a third aspect, the first switching mechanism may include: a first valve, which is a three-way valve, communicating among the heat-source-side heat exchanger, the expansion device and the thermal storage, and preferably a second valve, which is a three-way valve and located/provided between the first valve and the thermal storage, communicating among the first valve, the thermal storage and the first gas communication pipe.
According to a fourth aspect, the first switching mechanism may include: a first valve, which is a four-way valve, communicating among the heat-source-side heat exchanger, the thermal storage, the first gas communication pipe and the expansion device, wherein the first switching mechanism preferably further comprises a check valve that stops a backflow from the third fluid communication pipe to the first valve.
According to a fifth aspect, the refrigerant circuit may include a second switching mechanism located/provided on the second fluid communication pipe and communicating among the thermal storage, the expansion device and a fourth fluid communication pipe, wherein the fourth fluid communication pipe is communicating to a utilization-side heat exchanger.
According to a sixth aspect, the second switching mechanism may be a valve, which is a three-way valve, communicating among the thermal storage, the expansion valve and the utilization-side heat exchanger, wherein preferably an expansion device is provided on the fourth fluid communication pipe, located/provided between the second switching mechanism and the utilization-side heat exchanger.
According to a seventh aspect, the refrigerant circuit further comprising a receiver, which is preferably located/provided on the third fluid communication pipe, preferably between the expansion device and a/the utilization-side heat exchanger, wherein the receiver is configured to separate liquid refrigerant and gas refrigerant.
According to a eighth aspect, the refrigerant circuit further includes a subcooling heat exchanger, which is preferably located/provided between a/the utilization-side heat exchanger and the expansion device, more preferably between the utilization-side heat exchanger and a/the receiver.
According to a ninth aspect, the refrigerant circuit further includes an expansion device, particularly a storage side expansion valve, located on the fourth fluid communication pipe and between the second switching mechanism and the utilization-side heat exchanger, and a controller configured to select modes of operation, wherein the modes comprise:
According to a tenth aspect, the refrigerant circuit may further include an outside temperature sensor, a gas cooler out temperature sensor, a thermal storage medium temperature sensor, and a discharge side pressure sensor, provided on the high pressure side of the at least one compressor.
According to a eleventh aspect, the refrigerant circuit may further include a thermal storage unit having the thermal storage and comprising a water circuit, a refrigerant to phase change material (PCM) circuit or a refrigerant to water to phase change material (PCM) circuit, wherein the refrigerant to water to phase change material (PCM) circuit includes a heat exchanger, particularly a plate heat exchanger, and a circulating pump.
According to a twelfth aspect, the refrigerant circuit may further include a thermal storage unit including the first switching mechanism and the second switching mechanism.
According to a thirteenth aspect, the refrigerant circuit with the receiver may further include a heat exchange unit including the receiver and the subcooling heat exchanger.
According to a fourteenth aspect, a method for controlling a refrigerant circuit, particularly the above described refrigerant circuit, for a refrigerant apparatus with a thermal storage which is using CO2 as refrigerant, the method comprising different modes of operation, wherein the modes comprise:
According to a fifteenth aspect, in the method the first fluid communication pipe may communicate between a fluid side of a heat-source-side heat exchanger and one side of the thermal storage, the second fluid communication pipe may communicate between an expansion device and the other side of the thermal storage, the third fluid communication pipe may communicate to the expansion device, and/or the first gas communication pipe may communicate to a suction side of at least one compressor.
The modes of operation may further include a simultaneous cold storage making and refrigeration and/or cooling mode, wherein the controller is configured to prioritize refrigeration and/or cooling over cold storage making.
Yet, the cold storage making mode may include: a cold storage making mode only and a cold storage making and a refrigeration and/or cooling mode, and the cold storage using mode comprises: a refrigerant and/or cooling and using cold storage mode.
The method for controlling a refrigerant circuit can be used for controlling the refrigerant circuit of the disclosure. The method can also be used for controlling the thermal storage unit described above, or vice versa. Therefore, the further features disclosed in connection with the above description of the method for controlling a refrigerant circuit may also be applied to the refrigerant circuit or the thermal storage unit of the disclosure. The same applies vice versa for the heat exchange unit.
A more complete appreciation of the present disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings.
Several embodiments of the present disclosure will now be explained with reference to the drawings. It will be apparent to those skilled in the field of air-conditioning from this disclosure that the following description of the embodiments is provided for illustration only and not for the purpose of limiting the disclosure as defined by the appended claims.
The system of
Moreover, the condenser coil 112 as shown in
The phase change material 126 is selected so that the phase change material transitions from liquid to solid when cooling demand on the chiller system is low or non-existent. This may occur in the evening, when ambient temperatures are low. During the day, the solid or frozen phase change material 126 absorbs energy from the condenser 112 when the chiller system is running and increasing efficiency and capacity of the chiller system.
Furthermore,
In this regard, the term “connect” is used in the present disclosure to define that two entities, for example the “one side of the thermal storage” and the “thermal storage”, are connected with each other by a connecting means such as a “liquid pipe” or a “gas pipe” in such a manner that a fluid like a refrigerant can be liquid-tight and gas-tight transferred/exchanged/flow from one entity to the other one. In other words, the connecting means provide a fluidic connection.
The refrigerant circuit 1 further includes a first switching mechanism 31, which is located on the first fluid communication pipe 30 and fluidically connects the heat-source-side heat exchanger 11, the thermal storage 20, a third fluid communication pipe 50 and a first gas communication pipe 60 with each other, wherein the third fluid communication pipe 50 is fluidically connecting to the expansion device 12 and the first gas communication pipe 60 is fluidically connecting to a suction side of the compressor 10.
The shown refrigerant circuit 1 further includes a second switching mechanism 41 located on the second fluid communication pipe 40 and fluidically connects the thermal storage 20, the expansion device 12 and a fourth fluid communication pipe 70 with each other, wherein the fourth fluid communication pipe 70 is fluidically connecting to a utilization-side heat exchanger 80A.
The shown refrigerant circuit 1 also indicates that the refrigerant circuit 1 can further include an additional utilization-side heat exchanger 80B communicating on its liquid side with the expansion device 12 via the receiver 201 and on its gas side with the compressor 10.
As illustrated in
The shown thermal storage unit 100 further includes the first switching mechanism 31 communicating among the second thermal storage unit fluid port 32A, the third thermal storage fluid port 52A, the thermal storage unit gas port 62 and one side of the thermal storage 20, and the second switching mechanism 41 communicating among the first thermal storage unit fluid port 72, the third thermal storage unit fluid port 52A and the other side of the thermal storage 20.
Moreover, the in
According to the shown embodiment, the first switching mechanism 31 includes: a first valve 31A, which is a three-way valve, communicating among the second thermal storage unit fluid port 32A, the third thermal storage unit fluid port 52A and the thermal storage 20, and a second valve 31B, which is a three-way valve and located between the first valve 31A and the thermal storage 20, communicating among the first valve 31A, the thermal storage 20 and the thermal storage unit gas port 62.
Between the first valve 31A and the third thermal storage unit fluid port 52A is a check valve 31A provided that stops a backflow from the third thermal storage unit fluid port 52A to the first valve 31A.
The shown second switching mechanism 41 is a valve, which is a three-way valve, fluidically connecting the first thermal storage unit fluid port 72, the third thermal storage unit fluid port 52A and the thermal storage 20 with each other, wherein an expansion device 101 is located between the second switching mechanism 41 and the first thermal storage unit fluid port 72.
The second thermal storage unit fluid communication pipe 40 is connected with the third thermal storage unit fluid communication pipe 50 between the third thermal storage unit fluid port 52A and the check valve 53. A thermal storage unit gas communication pipe 60 fluidically connects the thermal storage unit gas port 62 and the first switching mechanism 31, particularly the second valve 31B, with each other.
Additionally, the thermal storage unit 100 includes a circulating pump 103 that is located on the second thermal storage unit fluid communication pipe 40, between the heat exchanger 102 and the thermal storage 20. Accordingly, the thermal storage has a closed loop, particularly using water as coolant. The circulating pump circulates the coolant through the thermal storage 20, thereby the coolant exchanges heat with the thermal storage material 21 of the thermal storage, and then to the heat exchanger 102, where the coolant again exchanges heat with the refrigerant of the refrigerant circuit 1. Hence, the circulating pump 103 is able to control the amount of thermal energy exchanged between the thermal storage 20, particularly the thermal storage material 21, and the refrigerant of the refrigerant circuit 1.
The in connection with
The shown heat exchange unit 200 further includes a heat exchange unit gas communication pipe 90 communicating between the heat exchange unit gas port 92 and the at least one compressor 10, a first heat exchange unit fluid communication pipe 30 communicating between the second heat exchange unit fluid port 32B and the heat-source-side heat exchanger 11, and a second heat exchange unit fluid communication pipe 50 communicating between the third heat exchange unit fluid port 52B and the first heat exchange unit fluid port 96.
The expansion device 12 is located on the second heat exchange unit fluid communication pipe 50, between the first heat exchange unit fluid port 96 and the third heat exchange unit fluid port 52B.
The shown heat exchange unit 200 further includes the above described receiver 201, which is located on the second heat exchange unit fluid communication pipe 50, between the first heat exchange unit fluid port 96 and the expansion device 12, wherein the receiver 201 is configured to separate liquid refrigerant and gas refrigerant. The heat exchange unit 200 further includes a fourth heat exchange unit fluid port 203 fluidically connecting the expansion device 12 and the additional utilization-side heat exchanger 80B disposed outside the heat exchange unit 200.
The shown heat exchange unit 200 further includes a third heat exchange unit fluid communication pipe 202 fluidically connecting the fourth heat exchange unit fluid port 203 with the expansion device 12 and is connected with the second heat exchange unit fluid communication pipe 50 between the first heat exchange unit fluid port 96 and the receiver 201.
The shown heat exchange unit 200 further includes a subcooling heat exchanger 204, which is located between the first heat exchange unit fluid port 96 and the receiver 201.
The refrigeration apparatus 300 includes three coolers such as refrigerators and freezers for storing food etc. and three air conditioners (indoor units) for cooling/heating an inside of a room, particularly a show room/shopping room. The three indoor units are each provided with one utilization-side heat exchanger 380A-380C and the three refrigerators are each provided with one additional utilization-side heat exchanger 301A-301C.
Additionally, the shown heat exchange unit 200 further includes a second compressor 310B and a third compressor 310C that are provided parallel to each other and upstream of the above described compressor 10 of the basic configuration. In this way, the three compressors 310A-310B build a two-stage compressor system, wherein the second compressor 310B communicates with the additional utilization-side heat exchangers 301A-301C to build a refrigeration circuit and the third compressor 310C communicates with the utilization-side heat exchangers 380A-380C to build an air-conditioning circuit. The three compressors 310A-310C can be variable capacity compressors and/or fixed capacity compressors, depending on the requirements of the refrigerant apparatus. All of the three compressors 310A-310C are hermetic scroll compressors.
The shown heat exchange unit 200 further includes an injection pipe 206 fluidically connecting a gas side of the receiver 201 with a suction side of the first compressor 10, 310A, wherein the injection pipe 206 is configured to inject intermediate-pressure refrigerant collected by the receiver 201 into the first compressor 10, 310A. As shown in
Additionally, the injection pipe 206 is provided with an expansion device 207, which is preferably located before the connection point of the injection pipe 206 with the high-pressure pipes 207, 208.
As already mentioned above,
Subsequently, the intermediate-pressure refrigerant flows to the receiver 201, a part of the refrigerant, particularly liquid intermediate-pressure refrigerant, flows from the receiver 201 to a first flow path 204A of the subcooling heat exchanger 204. The refrigerant flowing into the first flow path 204A is cooled by intermediate-pressure refrigerant flowing through the second flow path 204B, and the degree of subcooling of such refrigerant is increased. A part of the so subcooled liquid refrigerant flows through an expansion device 205, particularly a subcooling expansion valve, thereby reducing the pressure of the intermediate-pressure refrigerant further. The intermediate-pressure refrigerant flows into the second flow path 204B of the subcooling heat exchanger 204 and is evaporated by absorbing heat from the refrigerant flowing through the first flow path 204A of the subcooling heat exchanger 204.
The subcooled intermediate-pressure refrigerant flows so as to be branched into two main pipes providing the refrigerant to the refrigeration circuit and the air-conditioning circuit, where the refrigerant is branched again into three pipes providing the utilization-side heat exchangers 380A-380C of the indoor units and the additional utilization-side heat exchangers 301A-301C of the coolers with liquid refrigerant. Before entering the utilization-side heat exchangers 380A-380C, 301A-301C, the refrigerant flows through an expansion device, particularly an air-conditioning expansion valve or a cooler expansion valve, where the pressure of the intermediate-pressure refrigerant is reduced. Such refrigerant flows through the utilization-side heat exchangers and is evaporated by absorbing heat from example room air supplied by an air-conditioning fan of the indoor units.
The evaporated refrigerant of the utilization-side heat exchangers 380A-380C of the indoor units is rejoined and flows via a suction pipe back to a suction side of the third compressor 310C. The evaporated refrigerant of the additional utilization-side heat exchangers 301A-301C of the coolers is rejoined and flows via a suction pipe back to a suction side of the second compressor 310B. Thereby, the air-conditioning circuit and the refrigeration circuit are a closed loop. The evaporated refrigerant of the subcooling heat exchanger 204 is joined with intermediate-pressure refrigerant discharged from the second compressor 310B and the third compressor 310C and provided to the suction side of the first compressor 310A.
Additionally, gas intermediate-pressure refrigerant separated by the receiver 201 from the liquid intermediate-pressure refrigerant of the supercritical refrigerant, flows through an expansion device to reduce the pressure to a similar pressure as the pressure of the intermediate-pressure refrigerant discharged by the second compressor 310B and the third compressor 310C.
As described above, a part of the refrigerant, particularly liquid intermediate-pressure refrigerant, flows then from the receiver 201 to the first flow path 204A of the subcooling heat exchanger 204. The refrigerant flowing into the first flow path 204A is cooled by intermediate-pressure refrigerant flowing through the second flow path 204B, and the degree of subcooling of such refrigerant is increased. A part of the so subcooled liquid refrigerant flows through the expansion device 205 thereby reducing the pressure of the intermediate-pressure refrigerant further. The intermediate-pressure refrigerant flows into the second flow path 204B of the subcooling heat exchanger 204 and is evaporated by absorbing heat from the refrigerant flowing through the first flow path 204A of the subcooling heat exchanger 204.
The subcooled intermediate-pressure refrigerant flows then so as to provide the refrigerant only to the refrigeration circuit and not to the air-conditioning circuit, where the refrigerant is branched again into three pipes providing the additional utilization-side heat exchangers 301A-301C of the coolers with liquid refrigerant. Before entering the additional utilization-side heat exchangers 301A-301C, the refrigerant flows through the cooler expansion valve, where the pressure of the intermediate-pressure refrigerant is reduced. Such refrigerant flows through the additional utilization-side heat exchangers and is evaporated by absorbing heat from storage room air within the coolers.
Since the cooling operation is turned off, only the second compressor 310B and the first compressor 310A are in use, the third compressor 310 is turned off. Hence, the second compressor 310 draws low pressure refrigerant from the additional utilization-side heat exchangers 301A-301C of the coolers and provides intermediate-pressure refrigerant via the high-pressure pipe 207 to the first compressor 310A, which further compresses the refrigerant and discharges high-pressure refrigerant which flows to the heat-source-side heat exchanger 11, which acts as a gas cooler. Such refrigerant is cooled by dissipating heat to outdoor air supplied by an outdoor fan. The high-pressure refrigerant flowing out from the heat-source-side heat exchanger 11 flows then via the first fluid communication pipe 30 back to the first switching mechanism 31, thereby closing the refrigerant circuit.
Such refrigerant flows then as described above through the thermal storage 20, the expansion device 12, the receiver 201, the subcooling heat exchanger 204 and is then branched into the two main pipes providing the refrigerant to the refrigeration circuit and the air-conditioning circuit, closing the refrigerant circuit.
In this operation only the third compressor 310C and the first compressor 310A are in use, the second compressor 310B is turned off. The third compressor 310C draws the refrigerant directly from the thermal storage 20 and provides intermediate-pressure refrigerant to the first compressor which compresses the refrigerant further and discharges high-pressure refrigerant which flows to the heat-source-side heat exchanger 11, which acts as a gas cooler. The high-pressure refrigerant flowing out from the heat-source-side heat exchanger 11 flows then via the first fluid communication pipe 30 to the first switching mechanism 31. In this control mode the first valve 31A is set in such a manner that the high-pressure refrigerant flows as described above with
The subcooled intermediate-pressure refrigerant flows then via the second valve 31B back to the thermal storage 20 and by flowing through the thermal storage 20 cools the thermal storage 20, in particular the thermal storage material, thereby charges the thermal storage with cold.
The refrigeration operation while charging the thermal storage is similar to the above with regard to
Moreover, the capacity increasing unit may include a closed refrigerant circuit including a heat exchanger, a compressor, a heat-source-side heat exchanger cooled by a fan and an expansion device, wherein the heat exchanger exchanges heat with the heat exchange unit.
According to a further aspect, the combi unit may include a capacity increasing unit, comprising a closed refrigerant circuit including a heat exchanger, a compressor, a heat-source-side heat exchanger cooled by a fan and an expansion device, and a thermal storage unit comprising a heat exchanger, a thermal storage, including a thermal storage material, particularly a phase changing material (PCM), and a circulating pump, wherein the heat exchanger exchanges heat with the heat exchange unit.
[PTL 1] EP 2 402 681 A1
[PTL 2] EP 2 844 924 B1
| Number | Date | Country | Kind |
|---|---|---|---|
| 20205893.9 | Nov 2020 | EP | regional |
| 20205894.7 | Nov 2020 | EP | regional |
| 20205899.6 | Nov 2020 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2021/040591 | 11/4/2021 | WO |
