Cold storage device, parameter optimization solving method and system, processing equipment and storage medium

Abstract

The invention relates to a cold storage device, a parameter optimization solving method and system, processing equipment and a storage medium, and the method comprises the steps: building a cold storage model and a cold release model of the cold storage device according to the basic principles of heat balance and a one-dimensional heat exchange thermal resistance network, the cold storage model comprises an ethylene glycol side heat balance equation, a cold storage plate side heat balance equation and an ethylene glycol and cold storage plate heat transfer equation, and the cold release model comprises an ethylene glycol side heat exchange model and a cold storage plate side heat exchange model; adopting a least square method to fit physical property parameters of a secondary refrigerant and a cold storage agent of the cold storage device; based on the physical property parameters of ethylene glycol and water of the cold storage device, the established cold storage model and the cold release model are solved, the heat transferred to the secondary refrigerant from the cold storage plate of the cold storage device and the cold storage rate, the cold storage capacity, the cold release rate and the cold release capacity of the cold storage device are obtained, and the method can be widely applied to the field of cold storage devices.

Description

Technical Field

[0001] The present invention relates to the field of cold storage devices, and in particular to a cold storage device, a parameter optimization solution method, a system, a processing device and a storage medium. Background Art

[0002] At present, the measures taken to reduce carbon dioxide emissions include: 1) improving energy efficiency, reducing energy consumption, improving energy efficiency, and reducing carbon dioxide emissions by improving energy use, for example, using waste heat and waste pressure, using high-efficiency equipment, and using air conditioning and heating equipment reasonably; 2) using renewable energy sources such as solar energy and wind energy. Using these energy sources instead of fossil fuels can significantly reduce carbon dioxide emissions. As a new green, zero-carbon, and zero-waste method, natural gas pipeline pressure difference power generation and comprehensive energy utilization have the functions of potential conversion and reuse, consumption reduction, energy conservation and emission reduction, and zero carbon, and are currently receiving full attention in the field of natural gas transportation. Natural gas pressure difference power generation uses pressure energy to introduce natural gas into an expansion device, converts pressure energy into mechanical energy through an expander, and then drives the generator to generate electricity, ultimately realizing the conversion of pressure energy into electrical energy.

[0003] Natural gas pressure difference power generation mainly includes three systems: 1) Pressure difference power generation and transmission and distribution system, which is mainly used to expand high-pressure and large-flow natural gas through an impeller or rotor expander according to the isentropic principle. The expansion works on the impeller or rotor to drive the impeller to rotate. The rotating impeller or rotor outputs the expanded gas and transmits the rotational mechanical energy to the generator at the same time. The power generation is transmitted externally, mainly including an expander, a power transmission device, a generator and an auxiliary system. 2) Cold energy extraction and utilization system, according to different cooling needs in different seasons, the expanded low-temperature natural gas is divided into two paths. The two paths are exchanged with cold storage equipment to achieve cold exchange. One path is for the life cold in the station, that is, for the air conditioning system. Usually, ethylene glycol solution is used to exchange cold with low-temperature natural gas. The cold ethylene glycol is exchanged with water again in the non-explosion-proof area. Finally, the cold water enters the cold water air conditioning system to provide cooling for the cabinet room, corridor, dormitory, kitchen and office; the other path is a reserved external ice-making interface, that is, the heat medium inlet and outlet of the cold storage. If the cold energy is not used in ice making, the heat medium inlet and outlet of the cold storage can be closed. 3) Low-temperature natural gas reheating system: In order to meet the specified temperature requirements for natural gas transmission, the cold natural gas after cold energy extraction or expansion needs to be reheated to ≥0°C. A reheating heat exchanger with air as the heat source should be used. When the air temperature is low, an electric heating reheating heat exchanger is used. The combination of the two complements each other to meet production needs. If the seasonal temperature difference changes greatly, the electric heating reheater automatically adjusts the power put into use according to the air temperature reheating output temperature, thereby achieving energy-saving design.

[0004] Therefore, the cold storage equipment in the cold energy extraction and utilization system plays the dual functions of air conditioning cooling and ice making in this link, and plays a vital role in improving the comprehensive utilization efficiency of natural gas pressure difference power generation. The cold storage equipment used for cold storage, air conditioning cooling and ice making in the prior art mainly includes internal melting ice storage equipment, ice packaging cold storage equipment, ice crystal cold storage equipment and water cold storage equipment. However, the internal melting ice storage equipment has the problem of low heat exchange efficiency, the ice packaging cold storage equipment has the problem of uneven coolant flow distribution and low cold storage temperature, the ice crystal cold storage equipment has the problem of small refrigeration capacity and cold storage capacity, and the water cold storage equipment has the problem of easy rusting of pipes. Therefore, there is an urgent need for a device with a large cooling area (the cooling area is increased, which is beneficial to improve the heat exchange efficiency, thereby overcoming the heat exchange problems of the internal melting ice storage equipment The invention relates to a cold storage device with the advantages of: low efficiency), uniform distribution of coolant flow (which can balance the cold storage temperature, thus solving the problems of uneven distribution of coolant flow and low cold storage temperature in ice-packed cold storage equipment), compact structure and small thermal resistance (compact structure is conducive to modular and intensive layout, and multiple modules are compactly combined to achieve higher cold storage capacity in the same floor space; small thermal resistance means low friction in the flow of pipes, which is not easy to scale and rust, thereby improving the small refrigeration capacity and cold storage capacity of ice crystal cold storage equipment, and the easy rust of pipes in water cold storage equipment). Summary of the invention

[0005] In view of the above problems, the purpose of the present invention is to provide a cold storage device, a parameter optimization solution method, a system, a processing equipment and a storage medium, which have the advantages of large cooling area, uniform distribution of coolant flow, compact structure and small thermal resistance.

[0006] To achieve the above-mentioned object, the present invention adopts the following technical solutions: In a first aspect, a cold storage device is provided, comprising a box body, a plurality of cold storage plate groups and a partition, wherein each of the cold storage plate groups comprises a plurality of cold storage plates arranged in a transverse arrangement;

[0007] A plurality of cold storage plate groups are arranged in a transverse arrangement in the box body, and spaces for the passage of coolant are arranged at the upper and lower parts of the box body; a partition is arranged between every two cold storage plate groups; the partitions are numbered 1, 2, 3...n, the tops of the partitions with odd numbers are fixedly connected to the top of the box body, and the bottoms of the partitions with even numbers are fixedly connected to the bottom of the box body; a liquid inlet for the flow of coolant is arranged on one side of the lower part of the box body, and a liquid outlet for the flow of coolant is arranged on one side of the upper part of the box body;

[0008] Each of the cold storage plates contains a coolant, and two rows of protrusion structures are arranged on both sides of each of the cold storage plates, and the protrusion structures of two adjacent cold storage plates are arranged in an alternating manner to form a coolant flow channel.

[0009] Furthermore, the bottom plate of the box body is composed of a first outer partition plate, a perlite concrete layer and a first inner partition plate from outside to inside, and a first waterproof layer is provided on both sides of the perlite concrete layer;

[0010] The side wall of the box body is composed of a second outer partition, a first polyurethane foam plastic layer, a second inner partition and a metal film layer from the outside to the inside, and a second waterproof layer is also arranged between the second inner partition and the metal film layer;

[0011] The cover plate of the box body comprises a third outer partition plate, a second polyurethane foam plastic layer, a third inner partition plate and a rubber layer from the outside to the inside, and a waterproof layer is also arranged between the second polyurethane foam plastic layer and the third inner partition plate.

[0012] Furthermore, a plurality of blind holes are provided in the middle of each of the cold storage plates for bonding two sides of each of the cold storage plates.

[0013] In a second aspect, a parameter optimization solution method is provided, comprising:

[0014] According to the basic principles of heat balance and one-dimensional heat exchange thermal resistance network, a cold storage model and a cold release model of the cold storage device are established, wherein the cold storage model includes the heat balance equation on the ethylene glycol side, the heat balance equation on the cold storage plate side, and the heat transfer equation between the ethylene glycol and the cold storage plate, and the cold release model includes the heat exchange model on the ethylene glycol side and the heat exchange model on the cold storage plate side;

[0015] The least square method is used to fit the physical parameters of the coolant and the coolant storage agent in the cool storage device.

[0016] Based on the physical parameters of ethylene glycol and water in the cold storage device, the established cold storage model and cold release model are solved to obtain the heat transferred from the cold storage plate of the cold storage device to the coolant, as well as the cold storage rate, cold storage capacity, cold release rate and cold release capacity of the cold storage device.

[0017] Furthermore, the heat balance equation on the ethylene glycol side is:

[0018]

[0019] Among them, ΔQ brine It indicates the heat absorbed by the coolant flowing through the △l long pipe section; ρ brine Indicates the density of the coolant; C p,brine Indicates the constant pressure specific heat of the refrigerant; v brine represents the flow rate of the coolant when it flows through the cold storage plate; b represents the width of the coolant flow channel; t brine,in Indicates the liquid inlet temperature; t brine,out Indicates the liquid outlet temperature;

[0020] The heat balance equation on the cold storage plate side in the full water stage is:

[0021]

[0022] Among them, Q wali,i,j represents the heat transferred from the jth micro-element cold storage plate to the coolant during the period from i-1 to i; Q water,i,j represents the sensible heat of water in the jth microelement during the period from i-1 to i; C p,water Indicates the specific heat of the refrigerant at constant pressure; t water,i,j represents the temperature of water at time i and j; m water express The mass of water in the volume, A represents the thickness of the cold storage plate; Δτ represents the time taken by the coolant from entering the microelement to leaving the microelement;

[0023] The heat balance equation of new ice on the cold storage plate side during the ice-water coexistence stage is:

[0024]

[0025] The heat balance equation of old ice on the cold storage plate side during the ice-water coexistence stage is:

[0026]

[0027] Among them, Q ice,i,j′ represents the latent heat of the jth microelement of ice in the period from i-1 to i; Q ice,i,j″ represents the latent heat of the jth microelement of ice at time i; m ice,i-1,j represents the mass of the ice element j during the period from i-1 to i; C p,ice represents the specific heat of ice at constant pressure; t ice,i,j represents the temperature of ice at time i and at the jth element;

[0028] The heat balance equation on the cold storage plate side in the full ice stage is:

[0029]

[0030] Among them, Q ice,i,j represents the sensible heat of the jth microelement of ice in the period from i-1 to i; m ice,i,j represents the mass of the ice element j at time i;

[0031] The heat transfer equation between ethylene glycol and the cold storage plate before freezing is:

[0032]

[0033] Among them, Q wall,i,j ' represents the heat transferred from the cold storage plate to the coolant at time i; R brine,i,j R represents the convection heat transfer resistance between the coolant and the cold storage plate wall at time i; wall,i,j R represents the thermal resistance of the cold storage plate wall at time i; water,i,j represents the comprehensive thermal resistance of the jth infinitesimal water at time i;

[0034] The heat transfer equation between ethylene glycol and the cold storage plate after freezing is:

[0035]

[0036] Among them, R ice,i,j It represents the thermal resistance of the ice element at time i when the whole ice is frozen;

[0037] The heat transfer equation between the cold storage plate wall and the old ice during the freezing process is:

[0038]

[0039] Among them, R ice,i,j′ It represents the thermal resistance of the ice element at time i during the freezing process;

[0040] The heat transfer equation between old ice and new ice during the freezing process is:

[0041]

[0042] Among them, R ice′ Represents the thermal resistance of ice during the freezing process.

[0043] Furthermore, the ethylene glycol side heat exchange model is:

[0044]

[0045] Among them, Δq brine(释冷) Indicates the heat absorbed by the refrigerant flowing through the △l long pipe section during the cooling stage; v brine(释冷) Indicates the flow rate from the cold storage plate to the coolant;

[0046] The heat exchange model of the cold storage plate side is:

[0047]

[0048] Among them, Q wall,i,j(释冷) represents the heat transferred to the coolant from the micro-element cold storage plate 21 during the cooling stage i-1 to the period i j; Q water,i,j(释冷) It represents the sensible heat of the water in the jth microelement during the cooling release stage from i-1 to i period.

[0049] Furthermore, the cold storage rate of the cold storage device is:

[0050] Q s,i =ρ brine ·C brine ·v brine ·n·mb(t brine,i,j -t brine,i,o )

[0051] Among them, Q s,irepresents the cold storage rate of the equipment at time i; n represents the number of coolant flow channels; m represents the height of the coolant flow channel section; b represents the width of the coolant flow channel section; t brine,i,j represents the temperature of the coolant entering the cold storage device at time i; t brine,i,o Indicates the temperature of the coolant leaving the cold storage device at time i;

[0052] The cold storage capacity of the cold storage device is:

[0053]

[0054] Among them, Q s represents the cold storage capacity of the cold storage device; Ts represents the cold storage period; Q s,i Indicates the cold storage capacity of the cold storage device at time i;

[0055] The cooling rate of the cold storage device is:

[0056] Q r,i =ρ brine ·C brine ·v brine ·n·mb(t brine,i,0 -t brine,i,j )

[0057] Among them, Q r,i Indicates the cooling rate of the equipment at time i;

[0058] The cooling capacity of the cold storage device is:

[0059]

[0060] Among them, Q r Indicates the amount of cold released by the cold storage device; Tr indicates the cold release cycle; Q r,i Indicates the amount of cold released by the cold storage device at time i.

[0061] In a third aspect, a parameter optimization solution system is provided, comprising:

[0062] A model building module is used to establish a cold storage model and a cold release model of the cold storage device according to the basic principles of heat balance and one-dimensional heat exchange thermal resistance network, wherein the cold storage model includes a heat balance equation on the ethylene glycol side, a heat balance equation on the cold storage plate side, and a heat transfer equation between the ethylene glycol and the cold storage plate, and the cold release model includes a heat exchange model on the ethylene glycol side and a heat exchange model on the cold storage plate side;

[0063] The parameter fitting module is used to fit the physical parameters of the coolant and the coolant storage agent of the coolant storage device by using the least square method;

[0064] The solution module is used to solve the established cold storage model and cold release model based on the physical properties of ethylene glycol and water in the cold storage device, and obtain the heat transferred from the cold storage plate of the cold storage device to the coolant, as well as the cold storage rate, cold storage capacity, cold release rate and cold release capacity of the cold storage device.

[0065] In a fourth aspect, a processing device is provided, comprising computer program instructions, wherein the computer program instructions, when executed by the processing device, are used to implement the steps corresponding to the above-mentioned parameter optimization solution method.

[0066] In a fifth aspect, a computer-readable storage medium is provided, on which computer program instructions are stored, wherein the computer program instructions, when executed by a processor, are used to implement the steps corresponding to the above-mentioned parameter optimization solution method.

[0067] The present invention adopts the above technical solution, which has the following advantages:

[0068] 1. The present invention has a large cooling area, a stable ice forming and melting rate, a compact layout, and a high cold storage density per unit volume.

[0069] 2. The main functions of the protruding structure arranged on the cold storage plate of the present invention are, first, to organize the flow channel of the coolant ethylene glycol; second, to enhance heat exchange, because ethylene glycol generates disturbance when passing through the protruding structure, thereby increasing the heat transfer coefficient and thus enhancing the heat exchange effect; third, as a buffer space for the volume expansion of water in the plate when it freezes, it plays a buffering role on the expansion force exerted on the cold storage plate itself.

[0070] 3. The cold storage plate of the present invention is provided with blind holes, which can prevent the cold storage plate from bulging in the middle due to expansion when freezing, reducing the ethylene glycol flow channel area and damaging the cold storage device, thereby protecting the cold storage device.

[0071] 4. The coolant of the present invention flows in an orderly manner, has a uniform flow distribution, and has a good cooling effect.

[0072] 5. The heat transfer resistance of the present invention is small, and it can solve the problem that the air layer above the package in the prior art flat plate type cold storage equipment affects the surface heat exchange.

[0073] 6. Based on the principle of thermal balance, the present invention establishes a cold storage and release model and solution method for the device, which can provide a reference for the optimal design and performance improvement of new cold storage equipment.

[0074] In summary, the present invention can be widely used in the field of cold storage devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Throughout the accompanying drawings, the same reference numerals are used to represent the same components. In the accompanying drawings:

[0076] Figure 1 is a schematic structural diagram of a cold storage device provided by an embodiment of the present invention;

[0077] Figure 2 It is a schematic diagram of the structure of a cold storage plate provided by an embodiment of the present invention;

[0078] Figure 3 It is a schematic diagram of the side wall structure of the cold storage plate provided by one embodiment of the present invention;

[0079] Figure 4 It is a schematic diagram of the structure of the bottom plate of the cold storage plate provided by one embodiment of the present invention;

[0080] Figure 5 It is a schematic diagram of the cold storage plate cover structure provided by one embodiment of the present invention;

[0081] Figure 6 This is a schematic diagram of energy balance of a cold storage process provided by an embodiment of the present invention;

[0082] Figure 7 It is a schematic diagram of a parameter optimization solution process provided by an embodiment of the present invention;

[0083] Figure 8 It is a schematic diagram of a process flow in the all-water stage (sensible heat exchange of water) provided by an embodiment of the present invention;

[0084] Fig. 9 It is a schematic diagram of a process flow in a full ice stage (sensible heat exchange of ice) provided by an embodiment of the present invention;

[0085] Fig.10 It is a schematic diagram of a process flow in the ice-water coexistence stage (sensible heat exchange of ice-water mixture) provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0086] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0087] It should be understood that the terms used in the text are only for the purpose of describing specific example embodiments, and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used in the text may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0088] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0089] For ease of description, spatially relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figures, such as "inside", "outside", "inner side", "outer side", "below", "above", etc. Such spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figures.

[0090] The cold storage equipment used for cold storage air conditioning and ice making in the prior art mainly includes internal melting ice storage equipment, ice packaging storage equipment, ice crystal storage equipment and water storage equipment. The main problems of the above equipment are as follows:

[0091] (1) For the internal melting ice storage equipment, also known as the complete freezing ice storage system, it is a heat exchange device composed of coils immersed in a water-filled storage tank. When storing cold, the low-temperature ethylene glycol aqueous solution (or secondary refrigerant) produced by the chiller enters the coil for circulation, causing the water outside the tube to freeze (the water in the ice storage tank can be completely frozen). When releasing cold, the high-temperature ethylene glycol aqueous solution returning from the air-conditioning load end also enters the coil for circulation, gradually melting the ice on the outer surface of the coil; at the same time, the temperature of the ethylene glycol aqueous solution drops and is supplied to the user again. This system has the advantages of low failure rate, high IPF value, steel pipe or plastic pipe, easy maintenance, ethylene glycol solution in the pipe, small capacity, high flow rate, good heat transfer, closed system, not easy to leak and small storage tank volume. However, due to the need for a lower cold storage temperature and the supply of air-conditioning loads through a heat exchanger, there is a problem of low thermal efficiency.

[0092] (2) For ice-encapsulated cold storage equipment, the cold storage medium is encapsulated in a small spherical or plate-shaped container, and many such small cold storage containers are densely stacked in a sealed tank or an open tank body, thereby forming an encapsulated cold storage device. It has similar performance to the internal ice melting system, especially the closed system, simple structure, easy installation, operation and maintenance. The pressure storage tank can be designed as vertical or horizontal with various specifications and capacities according to different construction sites. It can also be set indoors and outdoors, on the ground or on the roof to save floor space, and some can even be used as architectural decorations. Encapsulated ice is a widely used cold storage system. Its main disadvantage is that the amount of refrigerant ethylene glycol used is large and the cold storage temperature is low.

[0093] (3) For ice crystal cold storage equipment, the cold storage freezing temperature is high, and the cold storage and cold release speed is high. However, the biggest disadvantage of this cold storage system is that the ice maker requires special design and manufacturing, which is expensive. At the same time, the refrigeration capacity and cold storage capacity are relatively small, and it is not currently suitable for large air conditioning systems.

[0094] (4) For water storage cooling equipment, the device structure is simple and easy to operate and manage. However, water of different temperatures in the cooling tank is easy to mix, which affects the cooling effect. In order to prevent the mixing of supply and return water, the application design has high requirements. In addition, the cooling density of the water storage system is low, and it only uses the sensible heat of water, which requires a large area and investment. Due to the use of open water storage tanks, water is easy to grow bacteria and algae when it comes into contact with air, and the pipes are easy to rust.

[0095] In summary, combined with the technical characteristics of the cold storage device that generates cold energy by pressure difference, there is an urgent need for a cold storage device with the advantages of large cooling area, uniform distribution of coolant flow, compact structure, and small thermal resistance. At the same time, in view of the current situation of parameter calculation and model lack of cold storage process of cold storage device, there is an urgent need for a cold storage device and its parameter optimization solution method to overcome the technical defects of the existing technology. Therefore, an embodiment of the present invention provides a cold storage device, including a box body, a plurality of cold storage plate groups and partitions, wherein each cold storage plate group includes a plurality of cold storage plates arranged in a transverse arrangement; a plurality of cold storage plate groups are arranged in a transverse arrangement in the box body, and the upper and lower parts of the box body are provided with spaces for the passage of a coolant; a partition is provided between every two cold storage plate groups; the partitions are numbered 1, 2, 3...n, the tops of the partitions numbered odd are fixedly connected to the top of the box body, and the bottoms of the partitions numbered even are fixedly connected to the bottom of the box body; a liquid inlet for the coolant to flow in is provided on one side of the lower part of the box body, and a liquid outlet for the coolant to flow out is provided on one side of the upper part of the box body; coolant is contained in each cold storage plate, and two rows of protrusion structures are provided on both sides of each cold storage plate, and the protrusion structures of two adjacent cold storage plates are staggered to form a coolant flow channel. An embodiment of the present invention also provides a parameter optimization solution method for a cold storage device, comprising: establishing a cold storage model and a cold release model of the cold storage device according to the basic principles of thermal balance and one-dimensional heat exchange thermal resistance network, wherein the cold storage model includes a heat balance equation on the ethylene glycol side, a heat balance equation on the cold storage plate side, and a heat transfer equation between the ethylene glycol and the cold storage plate, and the cold release model includes a heat exchange model on the ethylene glycol side and a heat exchange model on the cold storage plate side; using the least squares method to fit the physical parameters of the coolant and the coolant of the cold storage device; based on the physical parameters of ethylene glycol and water in the cold storage device, solving the established cold storage model and the cold release model to obtain the heat transferred from the cold storage plate to the coolant of the cold storage device, as well as the cold storage rate, cold storage capacity, cold release rate and cold release capacity of the cold storage device.

[0096] Example 1

[0097] like Figure 1 , Figure 2 As shown, this embodiment provides a cold storage device, including a box body 1, a cold storage plate group 2 and a partition 3, wherein the number of the cold storage plate groups 2 is five, and each cold storage plate group 2 includes four cold storage plates 21 arranged transversely.

[0098] The box body 1 is formed by a bottom plate 11, a side wall 12 and a cover plate 13 which are fixedly connected. Five cold storage plate groups 2 are arranged horizontally in the box body 1. Spaces for the passage of the coolant (ethylene glycol aqueous solution) are provided at the upper and lower parts of the box body 1. A partition 3 is provided between every two cold storage plate groups 2. The tops of the first and third partitions 3 in the box body 1 are fixedly connected to the cover plate 13 of the box body 1, and the bottoms of the second and fourth partitions 3 in the box body 1 are fixedly connected to the bottom plate 11 of the box body 1.

[0099] Each cold storage plate 21 contains a cold storage agent (water), and two rows of protrusion structures 22 are arranged on both sides of each cold storage plate 21, and the protrusion structures 22 of two adjacent cold storage plates 21 are arranged in an alternating manner to form a flow channel for the ethylene glycol aqueous solution. The disturbance generated when the ethylene glycol aqueous solution passes through the protrusion structure 22 can increase the heat transfer coefficient and enhance the heat transfer effect. At the same time, the protrusion structure 22 serves as a buffer space for the volume expansion of the water in the cold storage plate 21 when it freezes, and plays a buffering role on the expansion force exerted on the cold storage plate 21 itself.

[0100] A liquid inlet 14 is provided on one side of the lower part of the box 1 for the inflow of low-temperature ethylene glycol aqueous solution, and a liquid outlet 15 is provided on one side of the upper part of the box 1 for the outflow of the ethylene glycol aqueous solution after heat exchange. The low-temperature ethylene glycol aqueous solution is used to transfer cold energy to the chiller air conditioner in the pressure difference power generation cold energy system station or to outside the factory for ice making.

[0101] In a preferred embodiment, Figure 3 , Figure 4 and Figure 5 As shown, considering that the cold storage and cold release processes and the time between the completion of cold storage and the start of cold release are all long, in order to reduce the cold loss caused by heat exchange between the cold storage device and the outside world, the box 1 needs to take good cold preservation measures and also needs to be provided with functional structures such as protective layers and moisture-proof layers. Therefore, the bottom plate 11, side wall 12 and cover plate 13 of the box 1 all adopt a cold preservation structure. The bottom plate 11 of the box 1 is the first outer partition, the perlite concrete layer and the first inner partition from the outside to the inside, and the first waterproof layer is provided on both sides of the perlite concrete layer; the side wall 12 of the box 1 is the second outer partition, the first polyurethane foam plastic layer, the second inner partition and the metal film layer from the outside to the inside, and the first waterproof layer is also provided between the second inner partition and the metal film layer; the cover plate 13 of the box 1 is the third outer partition, the second polyurethane foam plastic layer, the third inner partition and the rubber layer from the outside to the inside, and the third waterproof layer is also provided between the second polyurethane foam plastic layer and the third inner partition.

[0102] In a preferred embodiment, the diameter of the protruding structures 22 on each cold storage plate 21 is 30 mm and the height is 5 mm. The protruding structures 22 on both sides of each cold storage plate 21 are staggered to form a 5 mm ethylene glycol aqueous solution flow channel.

[0103] In a preferred embodiment, three blind holes 23 are provided in the middle of each cold storage plate 21 for bonding the two sides of each cold storage plate 21 to prevent the cold storage plate 21 from bulging in the middle due to expansion when freezing, reducing the flow area of ​​the ethylene glycol aqueous solution and damaging the cold storage plate group 2, thereby protecting the cold storage plate group 2.

[0104] In a preferred embodiment, the coolant is a medium that transports the generated cold to the cold storage agent. The following aspects should be considered in its selection: it is in a liquid state at the operating temperature of the cold storage air conditioning system and does not solidify; it has a high specific heat capacity, and the system flow rate for transporting a certain amount of cold can be reduced; the density is relatively small, which is conducive to reducing the transportation resistance; when the system is running, there is no danger of combustion and explosion. Therefore, freezing temperature, corrosiveness, thermal properties, chemical stability and safety are all key considerations for the selection and proportioning of the coolant. Ethylene glycol is the most commonly used coolant in the cold storage air conditioning system, and additives have been added to prevent metal corrosion, foam formation, etc. Ethylene glycol solutions of different concentrations can be configured according to different needs. Ethylene glycol solutions of different concentrations have different properties. The higher the concentration, the lower the freezing point, but the greater the viscosity, which makes the flow resistance greater and the heat exchange effect worse; the lower the concentration, the better the heat exchange effect, the lower the resistance, but the higher the freezing point. After comprehensive comparison and analysis, the coolant of this embodiment adopts ethylene glycol aqueous solution with a concentration of 50%, which has the advantages of suitable freezing temperature, low corrosiveness, good thermal and chemical stability, safety and reliability, etc.

[0105] Example 2

[0106] This embodiment provides a parameter optimization solution method, comprising the following steps:

[0107] 1) Simplify the cold storage process and cold release process of the cold storage device.

[0108] Specifically, the cold storage process of a single cold storage plate 21 in the cold storage device includes four stages:

[0109] The first stage is when the water starts from an initial temperature T i Start cooling down to temperature T N , at this time ice crystals begin to appear, temperature T h The temperature of the water in the cold storage plate 21 decreases due to the reduction of internal energy, and even if it drops to the freezing point T m Below the supercooling state, its crystal phase still remains in the liquid phase.

[0110] The second stage is the process from the appearance of nucleation to the completion of ice crystal growth, which is called the ice crystal growth process. This process starts with ice crystal nucleation. Once nucleation occurs, dendritic ice crystals will grow from the nucleation point to the supercooled area, and finally form thin flakes of ice distributed in the area where the water has been cooled. In the short period from the beginning of nucleation to the completion of ice crystal growth, the latent heat released during the ice crystal formation process causes the water temperature, which was originally in a supercooled state, to rise to the freezing point corresponding to the pressure inside the ball. Once it rises to the freezing point, the growth of the ice crystal ends.

[0111] The third stage is the phase change process from the completion of ice crystal growth to the freezing of all water in the plate, which is called the water-ice latent heat storage process. This process starts from the completion of ice crystal growth, and the thick ice layer grows from the inner surface of the container to the center below the freezing point until the water in the plate is completely frozen.

[0112] The fourth stage is the process of cooling the ice from the freezing point to the same as the set temperature T of the coolant inlet, which is called the ice sensible heat storage process.

[0113] The cold release process of a single cold storage plate 21 in the cold storage device is opposite to the cold storage process, and the specific process will not be repeated.

[0114] Specifically, in the process of model establishment, in order to facilitate the solution, the minor factors in the complex cold storage process and the cold release process are simplified as follows without affecting the simulation results or having little effect on the simulation results:

[0115] ① Considering the large ratio of the area to the thickness of the cold storage plate 21, it is regarded as an infinitely large plane one-dimensional heat transfer.

[0116] ② Ignore the heat loss of the entire cold storage device.

[0117] ③ Ignore the changes in the volume of ice and water during the freezing and melting processes.

[0118] ④ Ignore the heat storage of the cold storage plate 21 wall.

[0119] ⑤ The heat transfer of the cold storage plate 21 is symmetrical, and the thickness center line of the cold storage plate 21 and the center line of the coolant flow channel are insulation lines.

[0120] 2) Based on the simplified results and the basic principles of heat balance and one-dimensional heat exchange thermal resistance network, a cold storage model of the cold storage device is established, including the heat balance equation on the ethylene glycol side, the heat balance equation on the cold storage plate side, and the heat transfer equation between ethylene glycol and the cold storage plate.

[0121] Specifically, the cold storage plate 21 is divided into n micro-elements along the flow direction of the brine, and each micro-element is calculated using the heat balance equation and the heat transfer equation at each time step, and the ice thickness at each moment is iteratively calculated, and the brine temperature calculated each time is used as the inlet temperature of the next micro-element, and the calculated temperature of each micro-element is used as the initial condition for the heat transfer calculation of the next micro-element, specifically:

[0122] 2.1) Establish the heat balance equation on the ethylene glycol side.

[0123] Specifically, take any microelement in the coolant flow channel as the control body j, with a length of △l. The heat absorbed by the coolant after flowing through the △l long pipe section should be equal to the heat transferred to the coolant by the cold storage plate 21, and the heat balance equation on the ethylene glycol side is obtained:

[0124] ΔQbrine =Q wall,i,j (1)

[0125] Among them, ΔQ brine It indicates the heat absorbed by the coolant flowing through the △l long pipe section, in W; Q wall,i,j It represents the heat transferred from the coolant to the coolant in the period from i-1 to i (i.e. the time required for the coolant to flow through the long pipe section △l) j micro-element cold storage plate 21, in units of W. Q wall,i,j The heat flow direction is from the cold storage plate 21 to the coolant, that is, the value is positive during the cold release process and negative during the cold storage process.

[0126] The above formula (1) is refined to obtain the heat balance equation on the ethylene glycol side:

[0127]

[0128] Among them, ρ brine Indicates the density of the coolant in kg / m 3 ; C p,brine Indicates the constant pressure specific heat of the refrigerant, in J / (kg·℃); v brine represents the flow rate of the coolant when it flows through the cold storage plate 21, in m / s; b represents the width of the coolant flow channel, in m; t brine,in Indicates the liquid inlet temperature in °C; t brine,out Indicates the liquid outlet temperature, which is also the temperature of the coolant entering j+1 microelement, in °C. Figure 6 The figure shows the schematic diagram of energy balance analysis of the control volume.

[0129] 2.2) Establish the heat balance equation on the cold storage plate side.

[0130] Specifically, the cold storage process on the cold storage plate side includes three stages: all water, ice and water coexisting, and all ice.

[0131] Specifically, during the all-water stage:

[0132]

[0133] Among them, Q water,i,j It represents the sensible heat of water in the jth microelement during the period from i-1 to i, in W; C p,water Indicates the specific heat of the refrigerant at constant pressure, in J / (kg·℃); t water,i,j represents the temperature of water at time i and j; m water express The mass of water in the volume, in kg; A represents the thickness of the cold storage plate 21, in m; Δτ represents the time taken by the coolant from entering the microelement to leaving the microelement, Δτ=Δl / v brine , unit is s.

[0134] Specifically, during the ice-water coexistence stage:

[0135] The heat balance equation when ice and water coexist is divided into two parts, one is the heat balance of the newly formed ice (referred to as new ice), and the other is the heat balance of the original ice (referred to as old ice). The water temperature in this process remains unchanged at 0°C. The heat balance equation of the new ice is:

[0136]

[0137] The heat balance equation for old ice is:

[0138]

[0139] Among them, Q ice,i,j′ represents the latent heat of the jth microelement of ice in the period from i-1 to i, in W; Q ice,i,j″ represents the latent heat of the jth microelement of ice at time i; m ice,i-1,j represents the mass of the ice element j during the period from i-1 to i, in kg; C p,ice Indicates the specific heat of ice at constant pressure, in J / (kg·℃); t ice,i,j represents the temperature of the ice at the jth element at time i.

[0140] Specifically, when the entire ice layer is in the stage, the heat balance equation on the cold storage plate side is:

[0141]

[0142] Among them, Q ice,i,j Represents the sensible heat of the jth microelement of ice in the period from i-1 to i, in W; m ice,i,j It represents the mass of the ice element j at time i, in kg.

[0143] 2.3) Establish the heat transfer equation between ethylene glycol and cold storage plate.

[0144] Specifically, the heat transfer equation before freezing is:

[0145]

[0146] Among them, Q wall,i,j ' represents the heat transferred from the cold storage plate to the coolant at time i; R brine,i,j represents the convection heat transfer resistance between the coolant and the cold storage plate wall at time i, in units of m·K / W; R wall,i,j represents the thermal resistance of the cold storage plate wall at time i, in units of m·K / W; R water,i,j It represents the comprehensive thermal resistance of the water element j at time i, in m·K / W:

[0147]

[0148] Here, α represents the convection heat transfer coefficient between the coolant and the outer wall of the cold storage plate 21, and the unit is W / (m·°C).

[0149] Specifically, the heat transfer equation after freezing is:

[0150]

[0151] Among them, R ice,o,j It represents the thermal resistance of the ice element at time i when the whole ice is frozen, in units of m·K / W:

[0152]

[0153] Among them, δ wall Indicates the thickness of the cold storage plate wall, in m; λ wall Indicates the thermal conductivity of the cold storage plate wall, in W / (m·K); λ water Indicates the thermal conductivity of water, in W / (m·K); λ e It represents the equivalent thermal conductivity of water in W / (m·K), and λ is obtained according to the existing empirical formula e =2.82λ water ; ice Represents the equivalent thermal conductivity of ice, with the unit of W / (m·K).

[0154] Specifically, during the freezing process:

[0155] The heat transfer equation between the cold storage plate wall and the old ice is:

[0156]

[0157] Among them, R ice,i,j′ It represents the thermal resistance of the ice element at time i during the freezing process, in units of m·K / W:

[0158]

[0159] Among them, δ ice,i,j It represents the thickness of the ice layer at the i-th moment, in m.

[0160] The heat transfer equation between old ice and new ice is:

[0161]

[0162] Among them, R ice′ It indicates the thermal resistance of ice during the freezing process, in m·K / W.

[0163] Specifically, the concentration of the ethylene glycol solution used as the coolant in the cold storage device of the present invention is about 50%, and the temperature entering the cold storage device is generally -5°C to -11°C. Under this condition, the physical properties of the ethylene glycol solution are: density ρ = 1045 kg / m 3 , dynamic viscosity is μ = 5.95 × 10 -3 Pa·s; thermal conductivity is λ=0.48W / (m·℃). The flow of the coolant in the flow channel is approximately treated as the flow in the tube. In the present invention, the width of the flow channel is 0.005m and the length is 0.49m, then the equivalent diameter d(m) is d=4f / U=(4×0.005×0.49) / (2(0.005+0.49))=0.0099m, where f represents the cross-sectional area of ​​the tube and U represents the circumference of the circle around the location. Re f Reynolds number, μ represents the flow velocity, the unit is m / s; Re f The value of is much smaller than 2300, so the flow of the coolant in the flow channel is laminar flow. The convective heat transfer coefficient α is obtained by the following formula (17):

[0164]

[0165] Among them, Nu f represents the Nusselt number; Pr f represents the Prandtl number, and v represents kinematic viscosity, unit is m 2 / s, a represents the thermal conductivity, the unit is m 2 / s; μ f It indicates the dynamic viscosity coefficient of ethylene glycol at the average temperature of the coolant in the flow channel, in kg / (s·m); μ w It indicates the dynamic viscosity coefficient of ethylene glycol at the temperature of the cold storage plate wall, with the unit of kg / (s·m).

[0166] 2.4) Based on the above heat transfer equation and heat balance equation, a group of equations consisting of the calculation formulas for heat and temperature in each stage of the cold storage model can be obtained, wherein the group of equations for the water cooling stage includes formulas (1), (4) and (7), the group of equations for the freezing stage includes formulas (1), (5), (13) and (14), and the group of equations for the ice cooling stage includes formulas (1), (6) and (9). Each group of equations is calculated by iteration.

[0167] 2.5) Based on the heat balance equation on the ethylene glycol side, the calculation formula for the cold storage rate and cold storage capacity of the cold storage device is determined as follows:

[0168] 2.5.1) Based on the heat balance equation on the ethylene glycol side, the calculation formula for the cold storage rate of the cold storage device is determined. The cold storage rate of the cold storage plate 21 in the cold storage device is equal to the cooling rate of the coolant, that is:

[0169] Q s,i =ρ brine ·C brine ·v brine ·n·mb(t brine,i,j -t brine,i,o )(18)

[0170] Among them, Q s,i represents the cold storage rate of the equipment at time i, in units of W; n represents the number of coolant flow channels; m represents the height of the coolant flow channel cross section, in units of m; b represents the width of the coolant flow channel cross section; t brine,i,j It indicates the temperature of the coolant entering the cold storage device at time i, in °C; t brine,i,o Indicates the temperature of the coolant leaving the cold storage device at time i.

[0171] 2.5.2) Integrate the calculated cold storage rate over time to determine the cold storage capacity of the cold storage device:

[0172]

[0173] Among them, Q s It indicates the cold storage capacity of the cold storage device, in J; Ts indicates the cold storage period, in s; Q s,i Indicates the cold storage capacity of the cold storage device at time i.

[0174] 3) Based on the simplified results, according to the basic principles of thermal balance and one-dimensional heat exchange resistance network, a cold release model of the cold storage device is established, specifically:

[0175] 3.1) Based on the simplified results, a cold release model of the cold storage device is established according to the basic principles of thermal balance and one-dimensional heat transfer thermal resistance network.

[0176] Specifically, Figure 6 The energy balance diagram of the cold release process is shown in FIG. Like the cold storage model of the cold storage device, the cold release model of the cold storage device includes a heat exchange model on the ethylene glycol side and a heat exchange model on the cold storage plate side.

[0177] The calculation of the water temperature rise process, the cold storage rate and the cold storage capacity are the same as the cold storage model. The following only introduces the melting stage of ice. In the melting stage of ice, the sensible heat of ice is ignored, and the heat transferred by the coolant through the cold storage plate wall is all used for melting ice. At the boundary layer between ice and water, the temperature is always kept at 0℃, and the equation form is similar to the cold storage model.

[0178] Specifically, the ethylene glycol side heat exchange model is:

[0179]

[0180] Among them, ΔQ brine(释冷) It indicates the heat absorbed by the refrigerant flowing through the △l long pipe section during the cooling stage, in W; v brine(释冷) It indicates the flow rate from the cold storage plate to the coolant, in m / s.

[0181] Specifically, the heat exchange model of the cold storage plate side is:

[0182]

[0183] Among them, Q wall,i,j(释冷) represents the heat transferred from the micro-element cold storage plate 21 to the coolant during the cooling stage i-1 to the time period i, in W; Q water,i,j(释冷) It represents the sensible heat of the water in the jth period from i-1 to i in the cooling release stage, in units of W.

[0184] 3.2) According to the cold release model of the cold storage device, determine the calculation formula of the cold release rate and cold release amount of the cold storage device:

[0185] 3.2.1) According to the heat balance, the cooling rate of the cooling plate 21 in the cooling device is equal to the heat release rate of the cooling medium, that is, the cooling rate of the cooling device is calculated as:

[0186] Q r,i =ρ brine ·C brine ·v brine ·n·mb(t brine,i,0 -t brine,i,j )(twenty two)

[0187] Among them, Q r,i It indicates the cooling rate of the equipment at time i, in W.

[0188] 3.2.2) Integrate the calculated cooling rate over time to determine the cooling capacity of the cooling storage device:

[0189]

[0190] Among them, Q r It indicates the cooling capacity of the cold storage device, in J; Tr indicates the cooling cycle, in s; Q r,i Indicates the amount of cold released by the cold storage device at time i.

[0191] 4) The least squares method is used to fit the physical parameters of the coolant (ethylene glycol) and the coolant (water) of the cold storage device.

[0192] Specifically, the thermodynamic and thermophysical properties of ethylene glycol and water are the basis for studying the flow and heat transfer of cold storage systems. The traditional chart-checking method is inefficient and inaccurate, and is not suitable for the requirements of system simulation and computer-aided design. It is replaced by a physical property calculation formula with higher accuracy. Since the physical property calculation of ethylene glycol and water must be repeatedly called and iteratively solved in the program, the accuracy, stability and speed of the thermophysical property calculation directly affect the overall calculation effect of the system. The present invention uses the least squares method to give the physical property fitting results of ethylene glycol and water, which has higher accuracy and can meet the results of engineering calculations.

[0193] Specifically, the physical property parameters include thermodynamic property data and thermophysical property data. The thermodynamic property data include density and specific heat at constant pressure. The thermophysical property data include dynamic viscosity, thermal conductivity, kinematic viscosity coefficient and Prandtl number. In the present invention, the concentration of ethylene glycol is 50%, the fitting temperature range is -10°C to 15°C, and the temperature range of water is 0°C to 15°C. The present invention uses a cubic polynomial to fit the physical property parameters of ethylene glycol and water, specifically:

[0194] 4.1) Fit the thermodynamic property data of ethylene glycol.

[0195] Specifically, the density of ethylene glycol (kg / m 3 )for:

[0196]

[0197] Among them, T brine Indicates the critical cooling temperature of ethylene glycol.

[0198] Specifically, the constant pressure specific heat (kJ / (kg·K)) of ethylene glycol is:

[0199]

[0200] 4.2) Fit the thermophysical property data of ethylene glycol.

[0201] Specifically, the thermal conductivity (W / (m·K)) of ethylene glycol is:

[0202]

[0203] Specifically, the dynamic viscosity coefficient of ethylene glycol (Pa·s) is:

[0204]

[0206] Specifically, the kinematic viscosity coefficient γ brine (m 2 / s) and the Prandtl number Pr brine They are:

[0207] γ brine =μ brine / ρ brine (28)

[0208] Pr brine =μ brine C brine ×10 3 / λ brine (29)

[0209] 4.3) Fit the thermodynamic properties data of water.

[0210] Specifically, the density of water (kg / m 3 )for:

[0211] ρ water =1000.5-0.00565×(t water +12) 1.887 (30)

[0212] Specifically, the specific heat of water at constant pressure (kJ / (kg·K)) is:

[0213] C water =-2.379154+5.527069e -2 ×(t water +273.15)-1.544152e -4 ×

[0214] (t water +273.15) 2 +1.440865e -7 ×(t water +273.15) 3 (31)

[0215] 4.4) Fit the thermophysical properties data of water.

[0216] Specifically, the thermal conductivity of water (W / (m·K)) is:

[0217] λ water =-0.369078+5.110079e -3 ×(t water +273.15)-6.189234e -4 ×

[0218] (t water +273.15) 2 +3.693561e -10 ×(t water +273.15) 3 (32)

[0219] Specifically, the data in Table 1 below are the physical property parameters of ethylene glycol and water calculated according to the above formula, and the correlation coefficients with the actual values obtained by referring to industry data tables and manuals are calculated by the following formula:

[0220]

[0221] where x i represents the actual parameter value; y i represents the corresponding parameter value after fitting, the parameter x' = ∑x i / n, and the parameter y' = ∑y i / n.

[0222] It can be seen from Table 1 that the correlation coefficients of all physical property parameters are greater than 0.99, which proves that the calculation formula using cubic polynomial fitting has high accuracy and can be applied in simulation and optimization design:

[0223] Table 1: Physical Property Parameters of Ethylene Glycol and Water

[0224]

[0225] 5) As Figure 7 shown, based on the physical property parameters of ethylene glycol and water of the cold storage device, the established cold storage model and cold release model are solved to obtain the heat transferred from the cold storage plate 21 of the cold storage device to the secondary refrigerant, as well as the cold storage rate, cold storage capacity, cold release rate and cold release capacity of the cold storage device, specifically:

[0226] 5.1) Establish a ice storage model.

[0227] Specifically, during the cold storage process, the phase state of the secondary refrigerant in the cold storage plate 21 first changes from water to ice-water mixture and finally to ice; the cold release process is the opposite. The heat exchange of different phase states with the secondary refrigerant is also different. To facilitate modeling, the ice content X is introduced, which is defined as the percentage of the mass M ice of ice in the cold storage plate 21 to the total mass M of the secondary refrigerant in the cold storage plate 21, and an ice storage model is established:

[0228] X = M ice / M(34)

[0229] where the range of the ice content X is [0, 1]. When X = 0, it means that the secondary refrigerant in the cold storage plate 21 is all water, in the all-water stage; when X = 1, it means that the secondary refrigerant in the cold storage plate 21 is all ice, in the all-ice stage; when 0 < X < 1, it means that the secondary refrigerant in the cold storage plate 21 is an ice-water mixture, in the ice-water coexistence stage.

[0230] 5.2) i = 0.

[0231] 5.3)i=i+Δτ.

[0232] 5.4)j=1.

[0233] 5.5) The mass M of ice in the cold storage plate 21 at time i ice The total coolant mass M in the cold storage plate 21 is input into the constructed ice storage model to determine the phase state in the cold storage plate 21 at time i.

[0234] 5.6) Based on the phase state and cold storage model in the cold storage plate 21 at time i, the cold storage rate and cold storage capacity of the cold storage device are calculated:

[0235] 5.6.1) If Figure 7 , Figure 8 As shown, when the cold storage plate 21 is in the full water stage, based on the cold storage model, the heat Q transferred from the cold storage plate 21 to the coolant is calculated. wall,i,j :

[0236] 5.6.1.1) Assume that the temperature of the water element j at time i is t water,i,j .

[0237] 5.6.1.2) Using the heat balance equation of the cold storage plate side in the cold storage model (3), according to the temperature t of the water element j at time i water,i,j and the physical properties of water, calculate the sensible heat Q of water water,i,j .

[0238] 5.6.1.3) Assume that the outlet temperature at time i is t brine,out .

[0239] 5.6.1.4) Using the heat balance equation of the glycol side in the cold storage model (2), according to the inlet temperature t at time i brine,in and the outlet temperature t brine,out and the physical properties of ethylene glycol, calculate the heat Q transferred from the cold storage plate 21 to the coolant wall,i,j .

[0240] 5.6.1.5) According to the heat transfer equation between ethylene glycol and the cold storage plate in the cold storage model (8), calculate the convective heat transfer coefficient α between the coolant and the outer wall of the cold storage plate 21.

[0241] 5.6.1.6) Based on the calculated convection heat transfer coefficient α, calculate the convection heat transfer resistance R between the coolant and the cold storage plate wall brine,i,j , Thermal resistance R of the cold storage plate wall wall,i,j The comprehensive thermal resistance R watwr,i,j .

[0242] 5.6.1.7) Using the heat transfer equation of ethylene glycol and the cold storage plate in the cold storage model (7), according to the temperature t of the jth element at time i water,i,j, the liquid inlet temperature at time i t brine,in and the outlet temperature t brine,out , the convection heat transfer resistance R between the coolant and the cold storage plate wall brine,i,j , Thermal resistance R of the cold storage plate wall wall,i,j The comprehensive thermal resistance R water,i,j , calculate the heat Q transferred from the cold storage plate 21 to the coolant wall,i,j ′.

[0243] 5.6.1.8) When Q wall,i,j and Q wall,i,j ′When the absolute value of the difference is less than the preset value ε given by the program, go to step 5.6.1.9); otherwise, go to step 5.6.1.3).

[0244] 5.6.1.9) When Q wall,i,j and Q water,i,j When the absolute value of the difference is less than ε, proceed to step 5.6.4); otherwise, proceed to step 5.6.1.1).

[0245] 5.6.2) If Figure 7 , Fig. 9 As shown, when the cold storage plate 21 is in the stage of full ice, the heat Q transferred from the cold storage plate 21 to the coolant is calculated based on the cold storage model. wall,i,j :

[0246] 5.6.2.1) Assume that the temperature of the infinitesimal ice at time j is t ice,i,j .

[0247] 5.6.2.2) Using the heat balance equation of the cold storage plate side in the cold storage model (6), according to the temperature t of the ice element at time i ice,i,j and the physical properties of water, calculate the sensible heat Q of ice ice,i,j .

[0248] 5.6.2.3) Assume that the outlet temperature at time i is t brine,out .

[0249] 5.6.2.4) Using the heat balance equation of the glycol side in the cold storage model (2), according to the inlet temperature t at time i brine,in and the outlet temperature t brine,out and the physical properties of ethylene glycol, calculate the heat Q transferred from the cold storage plate 21 to the coolant wall,i,j .

[0250] 5.6.2.5) According to the heat transfer equation between ethylene glycol and the cold storage plate in the cold storage model (8), calculate the convective heat transfer coefficient α between the coolant and the outer wall of the cold storage plate 21.

[0251] 5.6.2.6) Based on the calculated convection heat transfer coefficient α, calculate the convection heat transfer resistance R between the coolant and the cold storage plate wall brine,i,j , Thermal resistance R of the cold storage plate wall wall,i,j The comprehensive thermal resistance R water,i,j .

[0252] 5.6.2.7) Using the heat transfer equation of ethylene glycol and the cold storage plate in the cold storage model (7), according to the temperature t of the jth element at time i water,i,j , the liquid inlet temperature at time i t brine,in and the outlet temperature t brine,out , the convection heat transfer resistance R between the coolant and the cold storage plate wall brine,i,j , Thermal resistance R of the cold storage plate wall wall,i,j The comprehensive thermal resistance R water,i,j , calculate the heat Q transferred from the cold storage plate 21 to the coolant wall,i,j ′.

[0253] 5.6.2.8) When Q wall,i,j and Q wall,i,j ′When the absolute value of the difference is less than ε, proceed to step 5.6.2.9); otherwise, proceed to step 5.6.2.3).

[0254] 5.6.2.9) When Q wall,i,j and Q ice,i,j When the absolute value of the difference is less than ε, proceed to step 5.6.4); otherwise, proceed to step 5.6.2.1).

[0255] 5.6.3) If Figure 7 , Fig.10 As shown, when the cold storage plate 21 is in the ice-water coexistence stage, based on the cold storage model, the heat Q transferred from the cold storage plate 21 to the coolant is calculated. wall,i,j :

[0256] 5.6.3.1) Assume that the ice content of ice water at time i is X, and then obtain the mass m of ice in the cold storage plate 21 at this time ice,i,j .

[0257] 5.6.3.2) Using the heat balance equation of the cold storage plate side in the cold storage model (4), according to the mass m of ice in the cold storage plate 21 ice,i,j , calculate the latent heat of ice Q ice,i,j′ .

[0258] 5.6.3.3) Assume that the outlet temperature at time i is t brine,out .

[0259] 5.6.3.4) Using the heat balance equation of the glycol side in the cold storage model (2), according to the inlet temperature t at time i brine,in and the outlet temperature tbrine,out and the physical properties of ethylene glycol, calculate the heat Q transferred from the cold storage plate 21 to the coolant wall,i,j .

[0260] 5.6.3.5) According to the heat transfer equation between ethylene glycol and the cold storage plate in the cold storage model (8), calculate the convective heat transfer coefficient α between the coolant and the outer wall of the cold storage plate 21.

[0261] 5.6.3.6) Calculate the convection heat transfer resistance R between the coolant and the cold storage plate wall based on the obtained geometric data and the calculated convection heat transfer coefficient α brine,i,j , Thermal resistance R of the cold storage plate wall wall,i,j , comprehensive thermal resistance of water R water,i,j and the thermal resistance of ice R ice,i,j .

[0262] 5.6.3.7) Assume that the temperature of ice at time t ice,i,j .

[0263] 5.6.3.8) Using the heat transfer equation between ethylene glycol and the cold storage plate in the cold storage model (15), calculate the latent heat of ice Q ice,i,j′ .

[0264] 5.6.3.9) Using the heat transfer equation between ethylene glycol and the cold storage plate in the cold storage model (5), calculate the latent heat of ice Q ice,i,j″ .

[0265] 5.6.3.10) When Q ice,i,j′ and Q ice,i,j″ When the absolute value of the difference is less than ε, proceed to step 5.6.3.11); otherwise, proceed to step 5.6.3.7).

[0266] 5.6.3.11) Using the heat transfer equation between ethylene glycol and the cold storage plate in the cold storage model (9), calculate the heat Q transferred from the cold storage plate 21 to the coolant wall,i,j .

[0267] 5.6.3.12) When Q wall,i,j and Q wall,i,j′ When the absolute value of the difference is less than ε, proceed to step 5.6.3.13); otherwise, proceed to step 5.6.3.3).

[0268] 5.6.3.13) When Q ice,i,j′ and Q ice,i,j″ When the absolute value of the difference is less than ε, proceed to step 5.6.4); otherwise, proceed to step 5.6.3.1).

[0269] 5.6.4) Determine whether the microelement j is greater than the number N of cold storage plates 21. If so, proceed to step 5.6.5); otherwise, set j=j+1 and proceed to step 5.5).

[0270] 5.6.5) Determine whether time i is greater than ice storage time T s , if yes, go to step 5.6.6); otherwise, go to step 5.3).

[0271] 5.6.6) Use formulas (18) and (19) to calculate the cold storage rate and cold storage capacity of the cold storage device.

[0272] 5.7) Based on the phase state and the cold release model in the cold storage plate 21 at time i, the cold release rate and the cold release amount of the cold storage device are calculated. It should be noted that the calculation of the cold release rate and the cold release amount of the cold storage device is similar to the above-mentioned process of calculating the cold storage rate and the cold storage amount of the cold storage device, and no further details are given here.

[0273] Example 3

[0274] This embodiment provides a parameter optimization solution system, including:

[0275] A model building module is used to establish a cold storage model and a cold release model of the cold storage device according to the basic principles of heat balance and one-dimensional heat exchange thermal resistance network, wherein the cold storage model includes a heat balance equation on the ethylene glycol side, a heat balance equation on the cold storage plate side, and a heat transfer equation between the ethylene glycol and the cold storage plate, and the cold release model includes a heat exchange model on the ethylene glycol side and a heat exchange model on the cold storage plate side;

[0276] The parameter fitting module is used to fit the physical parameters of the coolant and the coolant storage agent of the coolant storage device by using the least square method;

[0277] The solution module is used to solve the established cold storage model and cold release model based on the physical properties of ethylene glycol and water in the cold storage device, and obtain the heat transferred from the cold storage plate of the cold storage device to the coolant, as well as the cold storage rate, cold storage capacity, cold release rate and cold release capacity of the cold storage device.

[0278] The system provided in this embodiment is used to execute the above-mentioned method embodiments. Please refer to the above-mentioned embodiments for specific processes and detailed contents, which will not be repeated here.

[0279] Example 4

[0280] This embodiment provides a processing device corresponding to the parameter optimization solution method provided in Embodiment 2. The processing device can be applicable to a client processing device, such as a mobile phone, a laptop computer, a tablet computer, a desktop computer, etc., to execute the method of Embodiment 2.

[0281] The processing device includes a processor, a memory, a communication interface and a bus, and the processor, the memory and the communication interface are connected through the bus to complete mutual communication. The memory stores a computer program that can be run on the processing device, and the processing device executes the parameter optimization solution method provided in this embodiment 2 when running the computer program.

[0282] In some implementations, the memory may be a high-speed random access memory (RAM), and may also include a non-volatile memory, such as at least one disk memory.

[0283] In some other implementations, the processor may be a central processing unit (CPU), a digital signal processor (DSP), or other general-purpose processors of various types, which are not limited herein.

[0284] In addition, the logic instructions in the above-mentioned memory can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0285] Those skilled in the art will understand that the structure of the above-mentioned computing device is only a partial structure related to the solution of the present invention, and does not constitute a limitation on the computing device to which the solution of the present invention is applied. The specific computing device may include more or fewer components, or combine certain components, or have a different arrangement of components.

[0286] Example 5

[0287] This embodiment provides a computer program product corresponding to the parameter optimization solution method provided in Embodiment 2. The computer program product may include a computer-readable storage medium on which computer-readable program instructions for executing the parameter optimization solution method described in Embodiment 2 are loaded.

[0288] Computer readable storage media can be tangible devices that hold and store instructions used by instruction execution devices. Computer readable storage media can be, for example, but not limited to, electronic storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any combination thereof.

[0289] The above embodiment provides a computer-readable storage medium, whose implementation principle and technical effect are similar to those of the above method embodiment, and will not be repeated here.

[0290] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0291] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0292] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0293] The above embodiments are only used to illustrate the present invention, wherein the structure, connection mode and manufacturing process of each component may be changed. Any equivalent transformations and improvements based on the technical solution of the present invention should not be excluded from the protection scope of the present invention.

Claims

1. A cold storage device, characterized in that: It includes a box body, a plurality of cold storage plate groups and a partition, wherein each of the cold storage plate groups includes a plurality of cold storage plates arranged in a transverse arrangement; A plurality of cold storage plate groups are arranged in a transverse arrangement in the box body, and spaces for the passage of coolant are arranged at the upper and lower parts of the box body; a partition is arranged between every two cold storage plate groups; the partitions are numbered 1, 2, 3...n, the tops of the partitions with odd numbers are fixedly connected to the top of the box body, and the bottoms of the partitions with even numbers are fixedly connected to the bottom of the box body; a liquid inlet for the flow of coolant is arranged on one side of the lower part of the box body, and a liquid outlet for the flow of coolant is arranged on one side of the upper part of the box body; Each of the cold storage plates contains a coolant, and two rows of protrusion structures are arranged on both sides of each of the cold storage plates, and the protrusion structures of two adjacent cold storage plates are arranged in an alternating manner to form a coolant flow channel.

2. A cold storage device according to claim 1, characterized in that: The bottom plate of the box body is composed of a first outer partition, a perlite concrete layer and a first inner partition from the outside to the inside, and a first waterproof layer is provided on both sides of the perlite concrete layer; The side wall of the box body is composed of a second outer partition, a first polyurethane foam plastic layer, a second inner partition and a metal film layer from the outside to the inside, and a second waterproof layer is also arranged between the second inner partition and the metal film layer; The cover plate of the box body comprises a third outer partition plate, a second polyurethane foam plastic layer, a third inner partition plate and a rubber layer from the outside to the inside, and a waterproof layer is also arranged between the second polyurethane foam plastic layer and the third inner partition plate.

3. A cold storage device according to claim 1, characterized in that: A plurality of blind holes are arranged in the middle of each cold storage plate for bonding the two sides of each cold storage plate.

4. A parameter optimization solution method for a cold storage device according to any one of claims 1 to 3, characterized in that: include: According to the basic principles of heat balance and one-dimensional heat exchange thermal resistance network, a cold storage model and a cold release model of the cold storage device are established, wherein the cold storage model includes the heat balance equation on the ethylene glycol side, the heat balance equation on the cold storage plate side, and the heat transfer equation between the ethylene glycol and the cold storage plate, and the cold release model includes the heat exchange model on the ethylene glycol side and the heat exchange model on the cold storage plate side; The least square method is used to fit the physical parameters of the coolant and the coolant storage agent in the cool storage device. Based on the physical parameters of ethylene glycol and water in the cold storage device, the established cold storage model and cold release model are solved to obtain the heat transferred from the cold storage plate of the cold storage device to the coolant, as well as the cold storage rate, cold storage capacity, cold release rate and cold release capacity of the cold storage device.

5. A parameter optimization method for a cold storage device as claimed in claim 4, characterized in that: The heat balance equation on the ethylene glycol side is: Among them, ΔQ brine Represents the heat absorbed by the coolant flowing through the △l long pipe section; ρ brine Indicates the density of the coolant; C p,brine Indicates the specific heat of the refrigerant at constant pressure; v brine represents the flow rate of the coolant when it flows through the cold storage plate; b represents the width of the coolant flow channel; t brine,in Indicates the liquid inlet temperature; t brine,out Indicates the liquid outlet temperature; The heat balance equation on the cold storage plate side in the full water stage is: Among them, Q wall,i,j represents the heat transferred from the coolant to the coolant by the coolant storage plate j during the period from i-1 to i; Q water,i,j represents the sensible heat of water in the jth microelement during the period from i-1 to i; C p,water Indicates the specific heat of the refrigerant at constant pressure; t water,t,j represents the temperature of water at time i and j; m water express The mass of water in the volume, A represents the thickness of the cold storage plate; Δτ represents the time taken by the coolant from entering the microelement to leaving the microelement; The heat balance equation of new ice on the cold storage plate side during the ice-water coexistence stage is: The heat balance equation of old ice on the cold storage plate side during the ice-water coexistence stage is: Among them, Q ice,i,j′ represents the latent heat of the jth microelement of ice in the period from i-1 to i; Q ice,i,j″ represents the latent heat of the jth microelement of ice at time i; m ice,i-1,j represents the mass of the ice element j during the period from i-1 to i; C p,ice represents the specific heat of ice at constant pressure; t ice,i,j represents the temperature of ice at time i and at the jth element; The heat balance equation on the cold storage plate side in the full ice stage is: Among them, Q ice,i,j represents the sensible heat of the jth microelement of ice in the period from i-1 to i; m ice,i,j represents the mass of the ice element j at time i; The heat transfer equation between ethylene glycol and the cold storage plate before freezing is: Among them, Q wall,i,j ' represents the heat transferred from the cold storage plate to the coolant at time i; R brine,i,j R represents the convection heat transfer resistance between the coolant and the cold storage plate wall at time i; wall,i,j R represents the thermal resistance of the cold storage plate wall at time i; water,i,j represents the comprehensive thermal resistance of the jth infinitesimal water at time i; The heat transfer equation between ethylene glycol and the cold storage plate after freezing is: Among them, R ice,i,j It represents the thermal resistance of the ice element at time i when the whole ice is frozen; The heat transfer equation between the cold storage plate wall and the old ice during the freezing process is: Among them, R ice,i,j′ It represents the thermal resistance of the ice element at time i during the freezing process; The heat transfer equation between old ice and new ice during the freezing process is: Among them, R ice′ Represents the thermal resistance of ice during the freezing process.

6. A parameter optimization method for a cold storage device as claimed in claim 5, characterized in that: The ethylene glycol side heat exchange model is: Among them, ΔQ brine (Release cold ) Indicates the heat absorbed by the refrigerant flowing through the △l long pipe section during the cooling stage; v brine (Release cold ) Indicates the flow rate from the cold storage plate to the coolant; The heat exchange model of the cold storage plate side is: Among them, Q wall,i,j(释冷) represents the heat transferred to the coolant from the micro-element cold storage plate 21 during the cooling stage i-1 to the period i j; Q water,i,j(释冷) It represents the sensible heat of the jth micro-element of water in the cooling release stage from i-1 to time period i.

7. A parameter optimization method for a cold storage device as claimed in claim 6, characterized in that: The cold storage rate of the cold storage device is: Q s,i =ρ brine ·C brine ·v brine ·n·m.b.(t brine,i,j -t brine,i,o ) Among them, Q s,i represents the cold storage rate of the equipment at time i; n represents the number of coolant flow channels; m represents the height of the coolant flow channel section; b represents the width of the coolant flow channel section; t brine,i,j represents the temperature of the coolant entering the cold storage device at time i; t brine,i,o Indicates the temperature of the coolant leaving the cold storage device at time i; The cold storage capacity of the cold storage device is: Among them, Q s represents the cold storage capacity of the cold storage device; Ts represents the cold storage period; Q s,i Indicates the cold storage capacity of the cold storage device at time i; The cooling rate of the cold storage device is: Q r,i =ρ brine ·C brine ·v brine ·n·m.b.(t brine,i,0 -t brine,i,j ) Among them, Q r,i Indicates the cooling rate of the equipment at time i; The cooling capacity of the cold storage device is: Among them, Q r Indicates the amount of cold released by the cold storage device; Tr indicates the cold release cycle; Q r,i Indicates the amount of cold released by the cold storage device at time i.

8. A parameter optimization solution system based on the parameter optimization solution method according to any one of claims 4 to 7, characterized in that: include: A model building module is used to establish a cold storage model and a cold release model of the cold storage device according to the basic principles of heat balance and one-dimensional heat exchange thermal resistance network, wherein the cold storage model includes a heat balance equation on the ethylene glycol side, a heat balance equation on the cold storage plate side, and a heat transfer equation between the ethylene glycol and the cold storage plate, and the cold release model includes a heat exchange model on the ethylene glycol side and a heat exchange model on the cold storage plate side; The parameter fitting module is used to fit the physical parameters of the coolant and the coolant storage agent of the coolant storage device by using the least square method; The solution module is used to solve the established cold storage model and cold release model based on the physical properties of ethylene glycol and water in the cold storage device, and obtain the heat transferred from the cold storage plate of the cold storage device to the coolant, as well as the cold storage rate, cold storage capacity, cold release rate and cold release capacity of the cold storage device.

9. A processing device, characterized in that: It includes computer program instructions, wherein when the computer program instructions are executed by a processing device, they are used to implement the steps corresponding to the parameter optimization solution method described in any one of claims 4 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, wherein the computer program instructions, when executed by a processor, are used to implement the steps corresponding to the parameter optimization solution method described in any one of claims 4 to 7.

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