TW202340660A - Refrigeration device and temperature adjustment system - Google Patents

Abstract

This refrigeration device 10 comprises a high-temperature-side refrigeration circuit 20 and a low-temperature-side refrigeration circuit 30. A water cooler 38 is provided between a compressor and a condenser in the low-temperature-side refrigeration circuit 30. When the refrigeration capacity of an evaporator of the low-temperature-side refrigeration circuit 30 is CL (Kw), the compression power of the compressor of the low-temperature-side refrigeration circuit 30 is PA (Kw), the cooling capacity of the water cooler 38 is CW (Kw), the refrigeration capacity of an evaporator of the high-temperature-side refrigeration circuit 20 is CH (Kw), the refrigerant circulation amount of the high-temperature-side refrigeration circuit 20 is F1 (Kg/hour), and the refrigerant circulation amount of the low-temperature-side refrigeration circuit 30 is F2 (Kg/hour), the refrigeration device 10 operates so as to satisfy such relationships [0.25*(CL+PA) ≤ CW ≤ 0.4*(CL+PA), 0.6*(CL+PA) ≤ CH ≤ 0.75*(CL+PA), 0.5*PA ≤ CW, and F1 ≤ F2].

Description

Refrigeration device and temperature control system

An embodiment of the present invention relates to a multi-type refrigeration device and a temperature control system equipped with a plurality of refrigeration circuits.

Binary refrigeration equipment, which is an example of a multi-type refrigeration equipment, is equipped with a high-temperature side refrigeration circuit and a low-temperature side refrigeration circuit, and is composed of an evaporator of the high-temperature side refrigeration circuit and a condenser of the low-temperature side refrigeration circuit. Cascade condensers that exchange heat with each other's refrigerants. At the cascade condenser, the high-temperature side refrigerant that has been expanded after condensation in the high-temperature side refrigeration circuit condenses the low-temperature side refrigerant that has been compressed in the low-temperature side refrigeration circuit. A large degree of supercooling is given to the condensed low-temperature side refrigerant, and then it is expanded and cooled. By this, if the binary refrigeration device is used, the temperature control object can be cooled down to an extremely low temperature region (JP6727422B).

Since the binary refrigeration device has two refrigeration circuits, its size is usually larger than that of the unit refrigeration device. In addition, in order to obtain high refrigeration capacity, it is necessary to use a compressor with high flow rate and high compression ratio. In this case, not only the size will further increase, but the cost of parts will also increase, and the energy consumption will also increase.

The inventor of this case aims at "auxiliary cooling of the high-temperature and high-pressure low-temperature side refrigerant flowing out from the compressor of the low-temperature side refrigeration circuit by using a water cooler (hereinafter referred to as a water cooler). We have examined the issue of obtaining the desired freezing capacity while suppressing the size and energy consumption of the entire device." If a water cooler is used, the environmental burden caused by the device can also be suppressed.

However, for example, when the refrigerant is evaporated at extremely low temperatures such as -70°C or below in the low-temperature side refrigeration circuit or when high refrigeration capacity output is required, the evaporator of the high-temperature side refrigeration circuit is connected. It is also necessary to ensure that there is a large freezing capacity. In other words, a large condensation load is required in the low-temperature side refrigeration circuit. In this case, if a water cooler is used, it will not make much contribution to the expected condensation load. Therefore, when extremely low temperatures or high refrigeration capacity are required, a high-temperature side refrigeration circuit with a large output or a large size will eventually be required. Even if a water cooler is used, it is difficult to effectively control the device size and energy. Consumption is suppressed.

In addition, the water used in the water cooler will have temperature changes according to the seasons. Therefore, in response to temperature changes of the water used in the water cooler, it may be necessary to adjust the refrigeration capacity required of the high-temperature side refrigeration circuit. In this case, if the stability of the control is taken into consideration, it is ideal that the adjustment range of the refrigeration capacity should be as small as possible relative to the steady-state operation.

In addition, the inventor of the present case has also learned that the setting of the refrigerant circulation amount of the high-temperature side refrigeration circuit and the low-temperature side refrigeration circuit affects the stable output of the desired refrigeration capacity and energy consumption when using the water cooler. It has a great influence on the suppression of quantity, the reasonable setting of compressor performance and the size of the device.

However, the inventors of the present case conducted diligent research taking into account the above-mentioned problems and knowledge, and discovered a multi-type refrigeration system that can suppress the increase in size, energy consumption, and environmental burden by using a water cooler. conditions to ensure the desired freezing capacity stably in the device.

An object of the present invention is to provide a refrigeration device and a temperature control system that can stably obtain desired refrigeration capabilities while suppressing enlargement, energy consumption, and environmental burden.

A refrigeration device according to one embodiment of the present invention is provided with a high-temperature side refrigeration circuit and a low-temperature side refrigeration circuit, and the evaporator of the high-temperature side refrigeration circuit and the condenser of the low-temperature side refrigeration circuit form a cascade condenser. Between the compressor and the condenser of the low-temperature side refrigeration circuit, there is a water cooler that cools the low-temperature side refrigerant circulated in the low-temperature side refrigeration circuit with water. Let the refrigeration capacity of the evaporator of the low-temperature side refrigeration circuit be CL (Kw), Let the compression power of the compressor of the low-temperature side refrigeration circuit be PA (Kw), And set the cooling capacity of the aforementioned water cooler to CW (Kw), And the refrigeration capacity of the evaporator of the aforementioned high-temperature side refrigeration circuit is set to CH (Kw), And set the refrigerant circulation volume of the aforementioned high-temperature side refrigeration circuit to F1 (Kg/hour), And when the refrigerant circulation volume of the low-temperature side refrigeration circuit is set to F2 (Kg/hour), Based on the relationship of 0.25×(CL+PA)≦CW≦0.4×(CL+PA) and 0.6×(CL+PA)≦CH≦0.75×(CL+PA) and 0.5×PA≦CW and F1≦F2, to operate.

The refrigeration device in one embodiment may be configured to operate in the relationship of 0.5×F2<F1≦0.7×F2.

The refrigeration device according to one embodiment may be configured such that the refrigerant circulation amount F1 of the high-temperature side refrigeration circuit is set to 470Kg/hour or more and 600Kg/hour or less, and the refrigerant circulation amount F2 of the low-temperature side refrigeration circuit is set to It operates at a temperature of 880Kg/hour or more and 920Kg/hour or less.

The system may be configured such that the water cooler cools the low-temperature side refrigerant with water in a range of 5°C or more and 28°C or less.

The system may be configured such that the water cooler circulates water from a water source without temperature adjustment to cool the low-temperature side refrigerant.

The refrigeration capacity CL of the evaporator of the low-temperature side refrigeration circuit may also be 30Kw or less.

The refrigeration capacity CL of the evaporator of the low-temperature side refrigeration circuit may also be 20Kw or more and 30Kw or less.

The refrigeration capacity CL of the evaporator of the low-temperature side refrigeration circuit may be 2 to 3 times the lower limit of the cooling capacity CW of the water cooler.

Furthermore, the refrigeration apparatus according to one of the embodiments may be further provided with a low-temperature side hot gas circuit that flows out from the compressor of the low-temperature side refrigeration circuit and passes through the water cooler; The low-temperature side refrigerant before the condenser of the low-temperature side refrigeration circuit is sent to the downstream side of the expansion valve of the low-temperature side refrigeration circuit and the upstream side of the evaporator.

Furthermore, a temperature control system according to one embodiment includes: the above-mentioned refrigeration device; and a fluid circulation device that circulates the fluid cooled by the evaporator of the low-temperature side refrigeration circuit.

According to the present invention, it is possible to obtain the desired refrigeration capability stably while suppressing the increase in size, energy consumption, and environmental burden.

Below, one of the implementation forms is described in detail with reference to the attached drawings.

〈Composition of temperature control system and refrigeration device〉 FIG. 1 is a diagram schematically showing a temperature control system S including a refrigeration device 10 according to one of the embodiments. The temperature control system S shown in FIG. 1 is equipped with a refrigeration device 10, a water supply device 100, a fluid circulation device 200, and a controller 300.

The refrigeration device 10 is a binary refrigeration device. The refrigeration device 10 includes a high-temperature side refrigeration circuit 20 and a low-temperature side refrigeration circuit 30 . The refrigeration device 10 uses the cascade condenser CC formed between the high-temperature side refrigeration circuit 20 and the low-temperature side refrigeration circuit 30 to make the high-temperature side refrigerant circulated in the high-temperature side refrigeration circuit 20 and the low-temperature side refrigeration circuit 30 The refrigerant on the low temperature side of the cycle performs heat exchange.

The high-temperature side refrigeration circuit 20 includes a high-temperature side refrigerant circulation unit 25, a subcooling circuit unit 26, and a high-temperature side hot gas circuit 27. The high-temperature side refrigerant circulation unit 25 combines the high-temperature side compressor 21 and the high-temperature side condenser. 22. The high-temperature side expansion valve 23 and the high-temperature side evaporator 24 are connected in this order to circulate the high-temperature side refrigerant.

The subcooling circuit unit 26 is provided with a subcooling flow path 26A, a subcooling control valve 26B provided in the subcooling flow path 26A, and a subcooling control valve 26B provided downstream of the subcooling flow path 26A. The subcooling heat exchanger 26C is located on the side. The subcooling flow path 26A connects "the portion on the downstream side of the high-temperature side condenser 22 and the upstream side of the high-temperature side expansion valve 23 in the high-temperature side refrigerant circulation section 25" to the high-temperature side compressor 21 .

The subcooling flow path 26A can send part of the high-temperature side refrigerant flowing out from the high-temperature side condenser 22 to the high-temperature side compressor 21 . By opening the subcooling control valve 26B, the high-temperature side refrigerant flowing in the subcooling flow path 26A expands and cools down, and then sends the refrigerant to the subcooling heat exchanger 26C.

The subcooling heat exchanger 26C cools the high-temperature side refrigerant flowing from the high-temperature side condenser 22 to the high-temperature side expansion valve 23 by the high-temperature side refrigerant flowing out from the subcooling control valve 26B. This makes it possible to provide a degree of subcooling to the high-temperature side refrigerant flowing from the high-temperature side condenser 22 to the high-temperature side expansion valve 23 .

The high-temperature side hot gas circuit 27 is provided with a high-temperature side hot gas flow path 27A, and a high-temperature side hot gas control valve 27B provided at the high-temperature side hot gas flow path 27A. "The portion downstream of the high-temperature side compressor 21 and upstream of the high-temperature side condenser 22 in the circulation section 25" and "the downstream side of the high-temperature side expansion valve 23 in the high-temperature side refrigerant circulation section 25 and the high-temperature side evaporator 24 Connect it to the "upstream part".

The high-temperature side hot gas flow path 27A can send the high-temperature side refrigerant flowing out from the high-temperature side compressor 21 to the downstream side of the high-temperature side expansion valve 23 and the upstream side of the high-temperature side evaporator 24 . By opening the high-temperature side hot gas control valve 27B, the high-temperature side refrigerant flowing in the high-temperature side hot gas flow path 27A can be mixed with the high-temperature side refrigerant flowing out from the high-temperature side expansion valve 23 .

The low-temperature side refrigeration circuit 30 includes a low-temperature side refrigerant circulation part 35, a low-temperature side hot gas circuit 36, and an injection circuit 37. The low-temperature side refrigerant circulation part 35 combines a low-temperature side compressor 31, a low-temperature side condenser 32, The low-temperature side expansion valve 33 and the low-temperature side evaporator 34 are connected in this order to circulate the low-temperature side refrigerant.

The low-temperature side hot gas circuit 36 is provided with a low-temperature side hot gas flow path 36A and a low-temperature side hot gas control valve 36B provided at the low-temperature side hot gas flow path 36A. "The portion downstream of the low-temperature side compressor 31 and upstream of the low-temperature side condenser 32 in the circulation section 35" and "the downstream side of the low-temperature side expansion valve 33 in the low-temperature side refrigerant circulation section 35 and the low-temperature side evaporator 34 Connect it to the "upstream part".

The low-temperature side hot gas flow path 36A can send the low-temperature side refrigerant flowing out from the low-temperature side compressor 31 to the downstream side of the low-temperature side expansion valve 33 and the upstream side of the low-temperature side evaporator 34 . By opening the low-temperature side hot gas control valve 36B, the low-temperature side refrigerant flowing in the low-temperature side hot gas flow path 36A can be mixed with the low-temperature side refrigerant flowing out from the low-temperature side expansion valve 33 .

The injection circuit 37 is provided with an injection flow path 37A, which connects the low-temperature side condenser 32 in the low-temperature side refrigerant circulation section 35, and an injection control valve 37B provided in the injection flow path 37A. The portion downstream of the low-temperature side expansion valve 33 and upstream of the low-temperature side expansion valve 33 is connected to the portion downstream of the low-temperature side evaporator 34 and upstream of the low-temperature side compressor 31 at the low-temperature side refrigerant circulation section 35 .

The injection flow path 37A can send the low-temperature side refrigerant flowing out from the low-temperature side condenser 32 to the downstream side of the low-temperature side evaporator 34 and the upstream side of the low-temperature side compressor 31 . By opening the injection control valve 37B, the low-temperature side refrigerant flowing in the injection flow path 37A can be mixed with the low-temperature side refrigerant flowing out from the low-temperature side evaporator 34 .

The above-mentioned cascade condenser CC is composed of the high-temperature side evaporator 24 of the high-temperature side refrigeration circuit 20 and the low-temperature side condenser 32 of the low-temperature side refrigeration circuit 30 . At the cascade condenser CC, the high-temperature side refrigerant expanded by the high-temperature side expansion valve 23 and became low temperature and low pressure exchanges heat with the low-temperature side refrigerant flowing out from the low-temperature side compressor 31 . Thereby, the low-temperature side refrigerant flowing out from the cascade condenser CC is condensed. Thereafter, the condensed low-temperature side refrigerant is expanded by the low-temperature side expansion valve 33 to become low temperature and low pressure, and flows into the low temperature side evaporator 34 . The types of high-temperature side refrigerant and low-temperature side refrigerant are not particularly limited. For example, the high-temperature side refrigerant system can also be R449A, and the low-temperature side refrigerant system can also be R508B.

In addition, the low-temperature side refrigeration circuit 30 is equipped with a water cooler 38 . The water cooler 38 is a heat exchanger and receives water and low-temperature side refrigerant inside. Thereafter, the water cooler 38 cools the low-temperature side refrigerant before flowing into the cascade condenser CC (low-temperature side condenser 32) by the water flowing inside. That is, in the refrigeration device 10, the low-temperature side refrigerant flowing out from the low-temperature side compressor 31 is first cooled by the water cooler 38, and then is cooled by the cascade condenser CC. for cooling. This provides a large degree of supercooling to the low-temperature side refrigerant system. In addition, the low-temperature side hot gas flow path 36A is configured to send the low-temperature side refrigerant flowing out from the low-temperature side compressor 31 before passing through the water cooler 38 and the low-temperature side condenser 32 (cascade condenser CC). On the downstream side of the side expansion valve 33 and on the upstream side of the low temperature side evaporator 34 .

The water used by the water cooler 38 is supplied from the water supply device 100 . The water supply device 100 is connected to the water source 101, and sends the water from the water source 101 to the water cooler 38 and the high temperature side condenser 22. The water supply device 100 is equipped with a water pump 102. Driven by the water pump 102, water is sent to the water cooler 38 and the high-temperature side condenser 22.

The water source 101 may be, for example, a tap water supply unit, a factory water supply unit, a well, or a tank storing water. In the water supply device 100 in this embodiment, energy saving is taken into consideration, and the water supply device 100 is not equipped with a device for adjusting the temperature of the water. That is, the water cooler 38 circulates the water from the water source 101 without adjusting its temperature to cool the low-temperature side refrigerant. However, a temperature regulating machine with water can also be used.

When the water source 101 is a tap water supply unit, a factory water supply unit, a well, a tank storing water, etc., the temperature of the water supplied by the water supply device 100 may vary depending on the season in most areas. It will fluctuate in the range of above 5℃ and below 28℃. Here, the water supply device 100 can also circulate water in the range of 10 L/min or more and 25 L/min or less. In this case, since the power of the water pump 102 is relatively suppressed, the energy consumption is suppressed. However, in the case of the above flow rate range, the cooling capacity (Kw) of the water supply device 100 may vary within a range of approximately 10 Kw or less and 16 Kw based on seasonal factors.

The water supply device 100 shown in the figure is provided with a first supply path 103A and a second supply path 103B that are branched into two from a common water source 101. The water from the first supply path 103A is supplied to the water cooler 38 , and the water from the second supply path 103B is supplied to the high temperature side condenser 22 . In addition, a constant flow valve 104 is provided on the downstream side of the water discharge port in the water cooler 38 . Thereby, the flow rate of the water flowing into the water cooler 38 is controlled to a specific value. In addition, the system may also adopt a structure in which the flow rate of water can be adjusted by a valve.

The fluid circulation device 200 circulates the fluid cooled by the low-temperature side refrigerant in the low-temperature side evaporator 34 of the low-temperature side refrigeration circuit 30 . The circulating fluid may be brine, etc., but the fluid is not particularly limited.

The fluid circulation device 200 includes a circulation flow path 201 connected to the low-temperature side evaporator 34, a three-way valve 202 constituting a part of the circulation flow path 201, a bypass flow path 203, and a circulation valve. Pu204. The low-temperature side evaporator 34 has a low-temperature side refrigerant passage portion and a fluid passage portion. The circulation flow path 201 has an upstream side flow path 201U connected to one of the openings of the passage portion of the fluid in the low-temperature side evaporator 34, and a flow path 201U connected to the fluid in the low-temperature side evaporator 34. The downstream side flow path 201D is connected through the opening on the other side of the part.

The three-way valve 202 forms a part of the downstream flow path 201D through the portion between two of the three ports. The remaining ports of the three-way valve 202 are A bypass flow path 203 is connected. The bypass flow path 203 connects the three-way valve 202 and the upstream side flow path 201U. The circulation pump 204 is provided in the upstream side flow path 201U. By driving the circulation pump 204, the fluid system circulates.

At the fluid circulation device 200, the fluid circulates in response to the driving of the circulation pump 204. The low-temperature side evaporator 34 is cooled by the low-temperature side refrigerant, and the fluid flowing out from the low-temperature side evaporator 34 is sent to a temperature control target (not shown) through the downstream side flow path 201D. The fluid that has passed through the temperature control object returns to the low-temperature side evaporator 34 via the upstream side flow path 201U. In addition, the three-way valve 202 can bypass the flow rate of the fluid returning to the low-temperature side evaporator 34 to the downstream side of the low-temperature side evaporator 34 without returning to the low-temperature side evaporator 34 . The flow rate of the fluid at the place is adjusted. This makes it possible to bypass the fluid cooled by the low-temperature side evaporator 34 to the downstream side of the low-temperature side evaporator 34 without returning to the low-temperature side evaporator 34 By adjusting the mixing ratio between "fluids", the temperature of the fluid sent to the temperature control object can be quickly adjusted.

The controller 300 controls the components of the refrigeration device 10 and the components of the fluid circulation device 200 . Specifically, the controller 300 can control the circulation amount (Kg/hour) of the high-temperature side refrigerant by controlling the drive state (number of revolutions) of the high-temperature side compressor 21 . In addition, the controller 300 can control the opening and closing and the opening degree of the high-temperature side hot gas control valve 27B. In addition, the controller 300 can control the circulation amount (Kg/hour) of the low-temperature side refrigerant by controlling the drive state (number of revolutions) of the low-temperature side compressor 31 . In addition, the controller 300 can control the opening and closing and the opening degree of the low-temperature side hot gas control valve 36B. In addition, the controller 300 can control the opening and closing and the opening degree of the injection control valve 37B.

The controller 300 can also be configured by a computer equipped with a CPU, ROM, RAM, etc., and controls the operations of the above-mentioned components according to a stored program. In addition, the controller 300 can also be configured by other processors or electrical circuits (such as FPGA (Field Programmable Gate Alley), etc.).

<Operating conditions> Next, the operating conditions of the refrigeration device 10 in this embodiment will be described. That is, in the refrigeration device 10 in this embodiment, the refrigeration capacity of the low-temperature side evaporator 34 of the low-temperature side refrigeration circuit 30 is set to CL (Kw), and the low-temperature side compressor 31 of the low-temperature side refrigeration circuit 30 is The compression power is set to PA (Kw), the cooling capacity of the water cooler 38 is set to CW (Kw), the refrigeration capacity of the high-temperature side evaporator 24 of the high-temperature side refrigeration circuit 20 is set to CH (Kw), and When the refrigerant circulation amount of the high-temperature side refrigeration circuit 20 is set to F1 (Kg/hour), and the refrigerant circulation amount of the low-temperature side refrigeration circuit 30 is set to F2 (Kg/hour), "0.25×(CL+PA) ≦CW≦0.4×(CL+PA) and 0.6×(CL+PA)≦CH≦0.75×(CL+PA) and 0.5×PA≦CW and F1≦F2” to operate.

In particular, the refrigerant circulation amount F1 of the high-temperature side refrigeration circuit 20 and the refrigerant circulation amount F2 of the low-temperature side refrigeration circuit 30 are preferably operated in the relationship of 0.5×F2<F1≦0.7×F2. Specifically, for example, when the refrigeration capacity CL of the low-temperature side evaporator 34 of the low-temperature side refrigeration circuit 30 is 30 Kw or less, more specifically, when it is 20 Kw or more and 30 Kw or less, the high-temperature side can be refrigerated. The refrigerant circulation amount F1 of the circuit 20 is set to 400Kg/hour or more and 800Kg/hour or less, and the refrigerant circulation amount F2 of the low-temperature side refrigeration circuit 30 is set to 780Kg/hour or more and 1400Kg/hour or less, and the operation is performed.

More specifically, for example, when the refrigeration capacity CL of the low-temperature side evaporator 34 is 20Kw or more and 24Kw, under the "relationship of 0.5×F2<F1≦0.7×F2", the high-temperature side refrigeration circuit 20 can also be The refrigerant circulation amount F1 is set to 470Kg/hour or more and 600Kg/hour or less, and the refrigerant circulation amount F2 of the low temperature side refrigeration circuit 30 is set to 880Kg/hour or more and 920Kg/hour or less, and the operation is performed. In addition, this numerical condition is only one example, and of course, the present invention is not limited to such conditions.

FIG. 2 is a Mollier chart illustrating the operating state of the low-temperature side refrigeration circuit 30 . Referring to FIG. 2 , in the low-temperature side refrigeration circuit 30 , the low-temperature side compressor 31 compresses the low-temperature side refrigerant through the transition shown by "1→2". With the transition shown by "2→3", the low-temperature side refrigerant is cooled by the water cooler 38. With the transition shown by "3→4", the low-temperature side refrigerant is cooled by the high-temperature side refrigerant at the cascade condenser CC. With the transition indicated by "4→5", the low-temperature side refrigerant is expanded by the low-temperature side expansion valve 33 and becomes a gas-liquid mixed state, thereby becoming a low-temperature and low-pressure state. Thereafter, through the transition shown by "5→1", the low-temperature side refrigerant exchanges heat with the fluid flowing through the fluid circulation device 20.

In FIG. 2 , the refrigeration capacity CL (Kw) of the low-temperature side evaporator 34 of the low-temperature side refrigeration circuit 30 and the compression power PA (Kw) of the low-temperature side compressor 31 of the low-temperature side refrigeration circuit 30 are used in the operating conditions. ), the cooling capacity CW (Kw) of the water cooler 38 and the refrigeration capacity CH (Kw) of the evaporator of the high-temperature side refrigeration circuit 20 are shown. The compression power PA is calculated from the refrigerant circulation amount F2×(h2-h1) of the low-temperature side refrigerant. h1 is the specific enthalpy at point "1" in Figure 2. h2 is the specific enthalpy at point "2" in Figure 2. When obtaining the compression power PA in this specification, the specific enthalpy h1 can be determined by measuring the inflow from the low-temperature side evaporator 34 to the low-temperature side compressor using a sensor based on the type of low-temperature side refrigerant. The pressure and temperature of the low-temperature side refrigerant before 31 are specified, and the measured pressure and temperature of the low-temperature side refrigerant are specified on the Morris line diagram (p-h line diagram, refrigerant physical property data) corresponding to the low-temperature side refrigerant. "The position corresponding to the temperature" is obtained. The specific enthalpy h2 can be determined by measuring the pressure and temperature of the low-temperature side refrigerant flowing out from the low-temperature side compressor 31 before flowing into the water cooler 38 by using sensors based on the type of low-temperature side refrigerant. On the Morris line diagram (p-h line diagram, refrigerant physical property data) corresponding to the low-temperature side refrigerant, the position corresponding to the measured pressure and temperature of the low-temperature side refrigerant is specified and obtained.

The above-described operating conditions are realized by the controller 300 mainly by controlling the drive state (number of revolutions) of the high-temperature side compressor 21 and the drive state (number of revolutions) of the low-temperature side compressor 31 . However, when operating under these operating conditions, the refrigeration device 10 can obtain a desired refrigeration capability while suppressing enlargement, energy consumption, and environmental burden. This matter is described in detail below.

First, under the relationship of "0.25×(CL+PA)≦CW≦0.4×(CL+PA) and 0.6×(CL+PA)≦CH≦0.75×(CL+PA)", through the low temperature side evaporator The refrigeration capacity CL of 34 + the compression power PA of the low-temperature side compressor 31, and the condensation load (CL + PA) required of the low-temperature side refrigeration circuit 30 are specified. However, in the above relationship, it is specified that the burden ratio of the cooling capacity CW (Kw) of the water cooler 38 in the condensation load (CL + PA) is 25% to 40%. However, the burden ratio of the cooling capacity CW (Kw) of the water cooler 38 is to increase the refrigeration capacity CL of the low-temperature side evaporator 34 as much as possible, and the size of the high-temperature side compressor 21 and the high-temperature side refrigeration circuit 20 This is an effective condition from the viewpoint of suppressing the overall size, energy consumption and environmental burden, and improving the stability of temperature control.

In addition, when the burden ratio of the cooling capacity CW (Kw) of the water cooler 38 generally becomes too large, for example, 60% or more, the condensed low-temperature side refrigerant cannot be sufficiently subcooled, and It becomes difficult to increase the refrigeration capacity CL of the low temperature side evaporator 34. On the other hand, when the burden ratio of the cooling capacity CW (Kw) of the water cooler 38 is generally too small, for example, 10% or less, the cooling system of the water cooler 38 does not function effectively, and It will be necessary to use a high-performance high-temperature side compressor. Based on this point of view, the burden ratio of the cooling capacity CW (Kw) of the water cooler 38 becomes 25% to 40%. In order to increase the refrigeration capacity CL of the low-temperature side evaporator 34 as much as possible, and to increase the cooling capacity CL of the high-temperature side compressor 21 This is good from the viewpoint of suppressing the size and the overall size of the high-temperature side refrigeration circuit 20. In addition, the cooling capacity CW of the water cooler 38 is within a wide range of the "condensation load required where compression power is not required". Therefore, it is important for the suppression of energy consumption and environmental burden. , the system becomes favorable.

In addition, when the burden ratio of the cooling capacity CW (Kw) of the water cooler 38 changes in the range of 25% to 40%, the refrigeration capacity CH of the high-temperature side evaporator 24 of the high-temperature side refrigeration circuit 20 is relatively It varies in the range of 60 to 75% depending on the condensation load (CL+PA). At this time, for example, when the basic operating state is assumed to be "a refrigeration capacity of 60% relative to the condensation load (CL + PA)", the maximum variation with respect to the cooling capacity CW of the water cooler 38 is The change rate of freezing capacity CH is 25%. Therefore, when the burden ratio of the cooling capacity CW (Kw) of the water cooler 38 is 25% to 40%, even if the cooling capacity CW (Kw) of the water cooler 38 changes, there is no need to deal with high temperatures. The refrigeration capacity CH of the high-temperature side evaporator 24 of the side refrigeration circuit 20 is greatly adjusted. In this case, since the operating driving range of the high-temperature side compressor 21 is suppressed to a relatively narrow range, it is possible to limit the high-temperature side compressor 21 to an ideal operating range in terms of stability. This operation also ensures excessive high performance without the need for a compressor. As a result, this is advantageous from the viewpoint of the stability of temperature control.

Next, in the relationship "0.5×PA≦CW", it is determined that the ratio of the cooling capacity CW (Kw) of the water cooler 38 to the compression power PA (Kw) of the low-temperature side compressor 31 is larger. . That is, the ratio of the cooling capacity CW (Kw) of the water cooler 38 to the compression power PA (Kw) of the low-temperature side compressor 31 is specified as the compression power PA (Kw) of the low-temperature side compressor 31 ) more than half. This relationship is the same as the above, and represents that "the cooling capacity CW (Kw) of the water cooler 38 is within a large range of the required condensation load", and it is able to obtain high-temperature side refrigeration. Device protection function when circuit 20 fails or stops. That is, even when the high-temperature side refrigeration circuit 20 breaks down or stops, similarly, when the cooling capacity CW (Kw) of the water cooler 38 is "0.5×PA" or more, By having the ability to offset more than half of the compression power PA of the low-temperature side compressor 31, the low-temperature side refrigerant system is cooled relatively early, and piping and the like can be protected. Based on this point of view, the relationship "0.5×PA≦CW" is valid.

In addition, under the relationship "F1≦F2", the refrigerant circulation amount F1 (Kg/hour) of the high-temperature side refrigeration circuit 20 is equal to or less than the refrigerant circulation amount F2 (Kg/hour) of the low-temperature side refrigeration circuit 30. Generally speaking, in a binary refrigeration device, the refrigerant circulation volume of the high-temperature side refrigeration circuit is larger than the refrigerant circulation volume of the lower-temperature side refrigeration circuit. On the other hand, in this embodiment, the refrigerant circulation amount F1 (Kg/hour) of the high-temperature side refrigeration circuit 20 is equal to or less than the refrigerant circulation amount F2 (Kg/hour) of the low-temperature side refrigeration circuit 30 . This case is advantageous from the viewpoint of miniaturization and cost reduction of the high-temperature side refrigeration circuit 20 . In particular, when the refrigeration device 10 is configured to operate in the relationship of 0.5×F2<F1≦0.7×F2, it is extremely advantageous from the viewpoint of miniaturization and cost reduction.

For example, when the refrigeration capacity CL of the low-temperature side evaporator 34 is 20Kw or more and 24Kw as described above, the refrigerant circulation amount F1 of the high-temperature side refrigeration circuit 20 can also be set to 470Kg/hour or more and 600Kg/hour or less, and The refrigeration device 10 is operated by setting the refrigerant circulation amount F2 of the low-temperature side refrigeration circuit 30 to 880Kg/hour or more and 920Kg/hour or less. The refrigerant circulation amount F1 of the high-temperature side refrigeration circuit 20 under these numerical conditions is a very small setting that is usually not adopted in the high-temperature side refrigeration circuit of a general binary refrigeration device between 20Kw and 24Kw. In this embodiment, by using the water cooler 38, it is possible to set such a very small circulation amount. However, when the relationship of 0.5×F2<F1≦0.7×F2 is set, specifically, when the refrigerant circulation amount F1 of the high-temperature side refrigeration circuit 20 is generally very small as described above, the high-temperature side can be refrigerated. The circuit 20 is effectively miniaturized. For example, the liquid receiver can be omitted, or even if the liquid receiver is used, the capacity can be kept small. Therefore, it is advantageous from the viewpoint of miniaturization and cost reduction of the high-temperature side refrigeration circuit 20 . In addition, generally speaking, a binary refrigeration device is configured to accommodate a high-temperature side refrigeration circuit and a low-temperature side refrigeration circuit in one housing. At this time, in this embodiment, the piping members of the water supply device 100 that introduce water into the water cooler 38 can also be housed in the same housing. At this time, if the high-temperature side refrigeration circuit 20 is large, it will be difficult to arrange the piping components of the water supply device 100 with good space efficiency. On the other hand, in this embodiment, the size of the high-temperature side refrigeration circuit 20 is reduced by suppressing the usage amount of the high-temperature side refrigerant. This makes it easy to downsize the entire apparatus. In addition, the refrigeration capacity CL of the low-temperature side evaporator 34 of the low-temperature side refrigeration circuit 30 may be 2 to 3 times the lower limit of the cooling capacity CW of the water cooler 38 . In this case, the water cooler 38 can be effectively operated, and good operating performance and temperature control performance can be obtained. The inventor of this case discovered this condition through various simulations and experiments.

As described above, in the refrigeration device 10 in this embodiment, the refrigeration capacity of the low-temperature side evaporator 34 of the low-temperature side refrigeration circuit 30 is set to CL (Kw), and the low-temperature side of the low-temperature side refrigeration circuit 30 is The compression power of the compressor 31 is set to PA (Kw), the cooling capacity of the water cooler 38 is set to CW (Kw), and the refrigeration capacity of the high-temperature side evaporator 24 of the high-temperature side refrigeration circuit 20 is set to CH (Kw). ), and when the refrigerant circulation amount of the high-temperature side refrigeration circuit 20 is set to F1 (Kg/hour), and the refrigerant circulation amount of the low-temperature side refrigeration circuit 30 is set to F2 (Kg/hour), "0.25×(CL +PA)≦CW≦0.4×(CL+PA) and 0.6×(CL+PA)≦CH≦0.75×(CL+PA) and 0.5×PA≦CW and F1≦F2” to operate. This makes it possible to obtain the desired refrigeration capability stably while suppressing enlargement, energy consumption, and environmental burden.

In particular, the refrigerant circulation amount F1 of the high-temperature side refrigeration circuit 20 and the refrigerant circulation amount F2 of the low-temperature side refrigeration circuit 30 are preferably operated in the relationship of 0.5×F2<F1≦0.7×F2. This case is advantageous from the viewpoint of miniaturization and cost reduction of the high-temperature side refrigeration circuit 20 . That is, in this embodiment, the piping members of the water supply device 100 that introduce water into the water cooler 38 can also be housed in the housing housing the high temperature side refrigeration circuit 20 and the low temperature side refrigeration circuit 30 . At this time, if the high-temperature side refrigeration circuit 20 is large, it will be difficult to arrange the piping components of the water supply device 100 with good space efficiency. On the other hand, in this embodiment, the size of the high-temperature side refrigeration circuit 20 is reduced by suppressing the usage amount of the high-temperature side refrigerant. This makes it easy to downsize the entire apparatus. Specifically, the high-temperature side refrigeration circuit 20 and the low-temperature side refrigeration circuit 30 are connected to form the cascade condenser CC, and the water cooler 38 is arranged close to these. When the refrigerant circulation amounts in the high temperature side refrigeration circuit 20 and the low temperature side refrigeration circuit 30 have the above relationship, in a common design, the low temperature side refrigeration circuit 30 is designed to be the higher temperature side refrigeration circuit 20 instead of the higher temperature side refrigeration circuit 20 . In this case, the piping and the like of the water supply device 100 can be arranged in a space at a position where the high-temperature side refrigeration circuit 20 is recessed relative to the low-temperature side refrigeration circuit 30 .

The embodiments of the present invention have been described above. However, the present invention is not limited to the above-mentioned embodiments. For example, although the refrigeration device 10 in the above embodiment is a two-dimensional refrigeration device, the present invention can also be applied to a three-dimensional refrigeration device. In this case, the refrigerant circulated in the mid-temperature side refrigeration circuit and/or the refrigerant circulated in the low-temperature side refrigeration circuit is cooled by the water cooler 38 .

10: Refrigeration device 20: High temperature side refrigeration circuit 21: High temperature side compressor 22: High temperature side condenser 23:High temperature side expansion valve 24:High temperature side evaporator 25: High temperature side refrigerant circulation department 26: Supercooling circuit part 26A: Supercooling flow path 26B: Subcooling control valve 26C: Subcooled heat exchanger 27: High temperature side hot gas circuit 27A: High temperature side hot air flow path 27B: High temperature side hot gas control valve 30: Low temperature measurement of refrigeration circuit 31: Low temperature side compressor 32: Low temperature side condenser 33: Low temperature side expansion valve 34:Low temperature side evaporator 35: Low temperature side refrigerant circulation department 36: Low temperature side hot gas circuit 36A: Low temperature side hot air flow path 36B: Low temperature side hot gas control valve 37:Injection circuit 37A: Jet flow path 37B:Injection control valve 38:Water cooler 100:Water supply device 101:Water source 102:Water pump 103A: 1st supply path 103B: Second supply path 104:Constant flow valve 200: Fluid circulation device 201: Circulation flow path 201D: Downstream side flow path 201U: Upstream side flow path 202: Three-way valve 203:Bypass flow path 204: Circulation pump 300:Controller CC: Cascade Cooler S: Temperature regulating device

[Fig. 1] is a diagram schematically showing a temperature control system including a refrigeration device according to one of the embodiments. [Fig. 2] is a Mollier chart illustrating the operating state of the low-temperature side refrigeration circuit included in the refrigeration device shown in Fig. 1. [Fig.

10: Refrigeration device

20: High temperature side refrigeration circuit

21: High temperature side compressor

22: High temperature side condenser

23:High temperature side expansion valve

24:High temperature side evaporator

25: High temperature side refrigerant circulation department

26: Supercooling circuit part

26A: Supercooling flow path

26B: Subcooling control valve

26C: Subcooled heat exchanger

27: High temperature side hot gas circuit

27A: High temperature side hot air flow path

27B: High temperature side hot gas control valve

30: Low temperature measurement of refrigeration circuit

31: Low temperature side compressor

32: Low temperature side condenser

33: Low temperature side expansion valve

34:Low temperature side evaporator

35: Low temperature side refrigerant circulation department

36: Low temperature side hot gas circuit

36A: Low temperature side hot air flow path

36B: Low temperature side hot gas control valve

37:Injection circuit

37A: Jet flow path

37B:Injection control valve

38:Water cooler

100:Water supply device

101:Water source

102:Water pump

103A: 1st supply path

103B: Second supply path

104:Constant flow valve

200: Fluid circulation device

201: Circulation flow path

201D: Downstream side flow path

201U: Upstream side flow path

202: Three-way valve

203:Bypass flow path

204: Circulation pump

300:Controller

CC: Cascade Cooler

S: Temperature regulating device

Claims (10)

A refrigeration device is provided with a high-temperature side refrigeration circuit and a low-temperature side refrigeration circuit, and the evaporator of the high-temperature side refrigeration circuit and the condenser of the low-temperature side refrigeration circuit form a cascade condenser, Between the compressor and the condenser in the low-temperature side refrigeration circuit, there is a water cooler that cools the low-temperature side refrigerant circulated in the low-temperature side refrigeration circuit with water. Let the refrigeration capacity of the evaporator of the low-temperature side refrigeration circuit be CL (Kw), Let the compression power of the compressor of the low-temperature side refrigeration circuit be PA (Kw), And set the cooling capacity of the aforementioned water cooler to CW (Kw), And the refrigeration capacity of the evaporator of the aforementioned high-temperature side refrigeration circuit is set to CH (Kw), And set the refrigerant circulation volume of the aforementioned high-temperature side refrigeration circuit to F1 (Kg/hour), And when the refrigerant circulation volume of the low-temperature side refrigeration circuit is set to F2 (Kg/hour), Based on the relationship of 0.25×(CL+PA)≦CW≦0.4×(CL+PA) and 0.6×(CL+PA)≦CH≦0.75×(CL+PA) and 0.5×PA≦CW and F1≦F2, to operate. A refrigeration device as described in claim 1, wherein, The operation is based on the relationship of 0.5×F2<F1≦0.7×F2. A refrigeration device as described in claim 2, wherein, The operation is performed by setting the refrigerant circulation amount F1 of the high-temperature side refrigeration circuit to 470Kg/hour or more and 600Kg/hour or less, and setting the refrigerant circulation amount F2 of the low-temperature side refrigeration circuit to 880Kg/hour or more and 920Kg/hour or less. The refrigeration device described in any one of claims 1 to 3, wherein, The water cooler uses water in the range of 5°C to 28°C to cool the low-temperature side refrigerant. A refrigeration device as described in claim 1, wherein, The water cooler circulates water from a water source without temperature adjustment to cool the low-temperature side refrigerant. A refrigeration device as described in claim 1, wherein, The refrigeration capacity CL of the evaporator of the aforementioned low-temperature side refrigeration circuit is 30Kw or less. A refrigeration device as described in claim 6, wherein, The refrigeration capacity CL of the evaporator of the aforementioned low-temperature side refrigeration circuit is 20Kw or more and 30Kw or less. A refrigeration device as described in claim 1, wherein, The refrigeration capacity CL of the evaporator of the low-temperature side refrigeration circuit is not less than 2 times but not more than 3 times the lower limit of the cooling capacity CW of the water cooler. A refrigeration device as described in claim 1, wherein, The system is further provided with: a low-temperature side hot gas circuit, which sends the low-temperature side refrigerant flowing out from the compressor of the aforementioned low-temperature side refrigeration circuit and passing through the aforementioned water cooler and before the condenser of the aforementioned low-temperature side refrigeration circuit to the aforementioned low temperature side. The part on the downstream side of the expansion valve of the side refrigeration circuit and on the upstream side of the evaporator. A temperature control system, the system has: A refrigeration device as described in claim 1; and The fluid circulation device circulates the fluid cooled by the evaporator of the low-temperature side refrigeration circuit.

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