Cold storage tank structure with expansion device

Abstract

The invention relates to a cold storage tank structure with an expansion device, which comprises a refrigerating unit, a first cold release pump, a cold storage pump, a second cold release pump, a chilled water supply pipe, a chilled water return pipe and a far-end cold storage tank, and the refrigerating unit, the chilled water supply pipe, a user terminal, the chilled water return pipe and the first cold release pump are sequentially communicated to form a refrigerating unit cold release loop. A far-end expansion assembly is arranged on the inner top of the far-end cold storage tank in a communicating mode and used for containing the volume variation caused by the temperature difference after cold storage and cold release of chilled water in the far-end cold storage tank and balancing the hydraulic power between the cold storage tanks. By designing the expansion device, overflowing chilled water is stored in the expansion device, the expansion device is arranged at the top of the cold storage tank, the system is simple in structure, stable and reliable in operation and low in cost, the problem of volume change of the chilled water before and after cold storage and discharge can be effectively solved, meanwhile, the problem of unbalanced resistance between the cold storage tanks can be solved, and the service life of the system is prolonged. Overflow is prevented, and low-carbon and energy-saving operation of the cold storage air conditioning system is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of air conditioning control technology, and more particularly to a cold storage tank structure with an expansion device. Background Technology

[0002] With the rapid development of my country's economy and the rapid growth of the tertiary industry, public buildings account for a large share of new construction. Central air conditioning is widely used, and its energy consumption accounts for about 40% of the total energy consumption of public buildings. In many cities, the air conditioning load can reach 50% of the local power grid's peak load. Therefore, energy-saving research in the air conditioning field has become a crucial part of my country's energy conservation efforts, and its significance for energy conservation is immense. Since the 1990s, the domestic refrigeration and heating industry has begun to adopt cold storage air conditioning systems. Among them, water-based cold storage air conditioning systems have been widely used in various projects due to their excellent economic benefits. Water-based cold storage technology utilizes off-peak electricity hours at night to produce chilled water using conventional refrigeration units. This chilled water is stored in tanks, and during peak electricity consumption hours the following day, it is used to supply cooling to users. However, due to objective differences in the length, local resistance, and installation elevation of the branch pipe networks of each cold storage tank, inherent hydraulic imbalances exist between the branches. This imbalance frequently leads to overflow of the chilled water tanks in practical water-based cooling systems. This is due to both the imbalance of resistance between the tanks and the expansion and contraction of the chilled water before and after storage and release. Frequent overflows not only waste water resources but also cause cooling losses in the air conditioning system. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a cold storage tank structure with an expansion device, addressing the shortcomings of the prior art.

[0004] The technical solution of this invention to solve the above-mentioned technical problems is as follows: A cold storage tank structure with an expansion device, applied to heat exchange in a user terminal, includes a refrigeration unit, a first cold release pump, a cold storage pump, a second cold release pump, a chilled water supply pipe, a chilled water return pipe, and a remote cold storage tank. The refrigeration unit, chilled water supply pipe, user terminal, chilled water return pipe, and first cold release pump are sequentially connected to form a refrigeration unit cold release circuit. The remote cold storage tank, second cold release pump, chilled water supply pipe, user terminal, and chilled water return pipe are sequentially connected... A remote cold storage tank cold release circuit is formed by connecting the refrigeration unit, the remote cold storage tank, and the cold storage pump in sequence to form a remote cold storage tank cold storage circuit; the first cold release pump is installed on the refrigeration unit return water pipe between the chilled water return pipe and the return water port of the refrigeration unit, the cold storage pump is installed on the cold storage hot end pipe branch between the refrigeration unit and the hot end pipe section of the remote cold storage tank, and the second cold release pump is installed on the cold release cold end pipe branch between the chilled water supply pipe and the cold end pipe section of the remote cold storage tank; The top of the remote cold storage tank is connected to a remote expansion assembly, which is used to accommodate the volume change of the chilled water in the remote cold storage tank caused by the temperature difference after cold storage and release, and to balance the hydraulic pressure between the pipelines.

[0005] Based on the above technical solution, the present invention can be further improved as follows: Further: The distal expansion assembly is cylindrical, including a distal expansion tank, and its radius... Determined by the following formula:

[0006]

[0007]

[0008] in, The volume of the distal expansion tank. The preset height for the remote expansion tank. α The coefficient of thermal expansion of chilled water is denoted as . For the volume of the remote cold storage tank, The density of the chilled water before cooling. This is the density of the chilled water after cooling.

[0009] The beneficial effects of the above-mentioned further solution are: due to the volume change caused by the temperature difference between the chilled water in the remote cold storage tank after cold storage and cold release, the radius of the remote expansion tank can be accurately calculated using the above formula. This can prevent chilled water from overflowing, avoid water waste, and reduce the cold loss of the air conditioning system.

[0010] This invention also provides a cold storage tank structure with an expansion device, applied to user terminal heat exchange, including a refrigeration unit, a first cold release pump, a cold storage pump, a second cold release pump, a chilled water supply pipe, a chilled water return pipe, a remote cold storage tank, and a near-end cold storage tank. The refrigeration unit, chilled water supply pipe, user terminal, chilled water return pipe, and first cold release pump are sequentially connected to form a refrigeration unit cold release circuit. The remote cold storage tank, second cold release pump, chilled water supply pipe, user terminal, and chilled water return pipe are sequentially connected to form a remote cold storage tank cold release circuit. The near-end cold storage tank, second cold release pump, chilled water supply pipe, user terminal, and chilled water return pipe are sequentially connected to form a remote cold storage tank cold release circuit. Water pipes are connected in sequence to form a near-end cold storage tank cold release circuit. The refrigeration unit, the far-end cold storage tank, and the cold storage pump are connected in sequence to form a far-end cold storage tank cold storage circuit. The refrigeration unit, the near-end cold storage tank, and the cold storage pump are connected in sequence to form a near-end cold storage tank cold storage circuit. The first cold release pump is installed on the refrigeration unit return water pipe between the chilled water return pipe and the return water port of the refrigeration unit. The cold storage pump is installed on the cold storage hot end pipe branch between the refrigeration unit and the hot end pipe section of the far-end cold storage tank. The second cold release pump is installed on the cold release cold end pipe branch between the chilled water supply pipe and the cold end pipe section of the far-end cold storage tank. The top of the distal cold storage tank is connected to a distal expansion assembly, which is used to accommodate the volume change of the chilled water in the distal cold storage tank caused by the temperature difference after cold storage and release, and to balance the hydraulic pressure between the various pipelines; the top of the proximal cold storage tank is connected to a proximal expansion assembly, which is used to accommodate the volume change of the chilled water in the proximal cold storage tank caused by the temperature difference after cold storage and release, and to balance the hydraulic pressure between the various pipelines.

[0011] Based on the above technical solution, the present invention can be further improved as follows: Further: The distal expansion assembly includes a distal expansion tank, the bottom of which is connected to the internal space of the distal cold storage tank, for accommodating the volume change caused by the temperature difference of the chilled water in the distal cold storage tank after cold storage and cold release; The proximal expansion assembly includes a proximal expansion tank and a proximal expansion pipe. The bottom of the proximal expansion tank is connected to the internal space of the proximal cold storage tank to accommodate the volume change caused by the temperature difference of the chilled water in the proximal cold storage tank after cold storage and release. The proximal expansion pipe is connected and disposed above the proximal expansion tank to balance the unbalanced resistance between the distal cold storage tank and the proximal cold storage tank.

[0012] The beneficial effects of the above-mentioned further solution are: by setting up a remote expansion tank and a near-end expansion tank, the volume change caused by the temperature difference between the chilled water in the cold storage tank after storage and release can be accommodated, that is, the expansion of the chilled water in the cold storage tank. Furthermore, by setting up the near-end expansion pipe, the unbalanced resistance value between the remote cold storage tank and the near-end cold storage tank can be balanced, that is, the additional friction resistance and local resistance of the remote cold storage tank and the near-end cold storage tank can be stored, thereby further preventing chilled water from overflowing.

[0013] Furthermore: the distal expansion tank is cylindrical, and its radius... Determined by the following formula:

[0014]

[0015]

[0016] in, The volume of the distal expansion tank. The preset height for the remote expansion tank. α The coefficient of thermal expansion of chilled water is denoted as . For the volume of the remote cold storage tank, The density of the chilled water before cooling. This is the density of the chilled water after cooling. The proximal expansion tank is cylindrical, and its radius is... Determined by the following formula:

[0017]

[0018]

[0019] in, The volume of the near-end expansion tank. The preset height for the near-end expansion tank. α The coefficient of thermal expansion of chilled water is denoted as . For the volume of the near-end cold storage tank, The density of the chilled water before cooling. This is the density of the chilled water after cooling.

[0020] The beneficial effects of the above-mentioned further solution are as follows: Since the volume change of chilled water in the remote cold storage tank and the near cold storage tank will be caused by the temperature difference after cold storage and cold release, the radius of the remote expansion tank and the near expansion tank can be accurately calculated by the above formula. This can avoid chilled water overflow, avoid water waste, and also reduce the cold loss of the air conditioning system.

[0021] Furthermore: the proximal expansion tube is tubular, and its height... Determined by the following formula:

[0022]

[0023]

[0024]

[0025]

[0026] in, β This is the residual coefficient. ab The pipe section refers to the additional return water pipe section that the distal cold storage tank passes through compared to the proximal cold storage tank. a Point is the return water pipe ab The branching point of the pipe section, b The point is the end point of the additional straight pipe section traversed by the distal cold storage tank compared to the proximal cold storage tank. cd The pipe section refers to the additional water supply pipe section that the distal cold storage tank passes through compared to the proximal cold storage tank. c Point for cd The confluence point of the pipe section, d The point is the starting point of the additional straight pipe section that the distal cold storage tank traverses compared to the proximal cold storage tank. The unbalanced resistance value between the far-end cold storage tank and the near-end cold storage tank under cold storage conditions. The unbalanced resistance value between the far-end cold storage tank and the near-end cold storage tank under cooling conditions. The larger one, for ab The unbalanced resistance value of the pipe section, for ab Friction resistance along the pipe section, for a Point and b The sum of the local resistances of the corresponding resistance components at the point. for a The point corresponds to the local resistance of the resistance component. for ab The frictional resistance coefficient of the pipe section, for ab The length of the pipe section for ab The diameter of the pipe section, The density of chilled water, The flow rate of the chilled water. for a Point and b The sum of the local resistance coefficients of the corresponding resistance components at the point. for aThe local resistance coefficient of the resistance component at the point. for ab Specific friction of the pipe section.

[0027] The beneficial effect of the above-mentioned further solution is that, in a system of multiple cold storage tanks, the cold storage tank farther from the confluence point has a greater frictional resistance, which will cause an imbalance in the water level between the cold storage tanks. By calculating the difference in unbalanced resistance between the far-end cold storage tank and the near-end cold storage tank, the height of the near-end expansion tube can be accurately determined, ensuring that the chilled water will not overflow under both cooling and cooling conditions.

[0028] Further: If If <0, then the distal expansion assembly further includes a distal expansion tube, which is connected above the distal expansion tank to balance the unbalanced resistance between the distal cold storage tank and the proximal cold storage tank.

[0029] The beneficial effect of the above further solutions is: if If the value is less than 0, it indicates that the chilled water in the remote expansion tank may overflow. Therefore, installing a remote expansion pipe can completely prevent chilled water from overflowing in extreme cases.

[0030] Further: The height of the distal expansion tube is .

[0031] Furthermore: the number of the near-end cold storage tanks is multiple, and the height of the near-end expansion tube is determined by the following method: First, determine the height of the proximal expansion tube of the proximal cold storage tank that is closest to the distal cold storage tank according to the calculation formula; Then, based on the height of the proximal expansion tube of the proximal cold storage tank closest to the distal cold storage tank, calculate the height of the proximal expansion tube of the next closest proximal cold storage tank, and so on, until the height of the proximal expansion tube of the proximal cold storage tank furthest from the distal cold storage tank is calculated.

[0032] The beneficial effect of the above-mentioned further scheme is that when there are multiple near-end cold storage tanks, the height of the near-end expansion tube of the nearest near-end cold storage tank can be calculated first for the far-end cold storage tank and the nearest near-end cold storage tank. Then, the height of the near-end expansion tube of the two tanks can be calculated together with that of the next closest near-end cold storage tank. This gives the height of the near-end expansion tube of the next closest near-end cold storage tank, thus allowing the calculation of the height of the near-end expansion tube of each near-end cold storage tank. Similarly, to ensure standardized processing, cost control, and maximum safety, each expansion device is designed based on the resistance value of the most unfavorable branch.

[0033] The beneficial effects of this invention are as follows: The cold storage tank structure with an expansion device of this invention stores overflowing chilled water in the expansion device. The system has an expansion device installed at the top of the cold storage tank, which is simple in structure, stable and reliable in operation, and low in cost. It can effectively solve the problem of volume change of chilled water before and after storage and release, and can also solve the problem of resistance imbalance between cold storage tanks, prevent overflow, and thus ensure the low-carbon and energy-saving operation of the cold storage air conditioning system. It is suitable for the renovation of existing cold storage tank systems and new construction projects. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of a cold storage tank structure with an expansion device according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a cold storage tank structure with an expansion device according to another embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a distal expansion assembly according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a distal expansion assembly according to another embodiment of the present invention; Figure 5 This is a schematic diagram of a cold storage tank structure with an expansion device according to another embodiment of the present invention.

[0035] The attached diagram lists the components represented by each number as follows: 1. Refrigeration unit; 2. First cold release pump; 3. Cold storage pump; 4. Second cold release pump; 5. First electric valve; 6. Second electric valve; 7. Third electric valve; 8. Fourth electric valve; 9. Fifth electric valve; 10. Sixth electric valve; 11. Chilled water supply pipe; 12. Chilled water return pipe; 13. Remote cold storage tank; 14. Near-end cold storage tank. 13-1, Distal expansion assembly; 13-3, Distal hot-end valve; 13-4, Distal cold-end valve; 13-5, Distal expansion tube; 13-6, Distal expansion tank; 14-1, Proximal expansion assembly; 14-3, Proximal hot-end valve; 14-4, Proximal cold-end valve; 14-5, Proximal expansion tube; 14-6, Proximal expansion tank. Detailed Implementation

[0036] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0037] like Figure 1As shown, a cold storage tank structure with an expansion device is used for heat exchange at a user terminal. It includes a refrigeration unit 1, a first cold release pump 2, a cold storage pump 3, a second cold release pump 4, a chilled water supply pipe 11, a chilled water return pipe 12, and a remote cold storage tank 13. The refrigeration unit 1, chilled water supply pipe 11, user terminal, chilled water return pipe 12, and first cold release pump 2 are sequentially connected to form a refrigeration unit cold release circuit. The remote cold storage tank 13, second cold release pump 4, chilled water supply pipe 11, user terminal, and chilled water return pipe 12 are sequentially connected to form a remote cold storage tank. The cold storage tank cold release circuit is formed by sequentially connecting the refrigeration unit 1, the remote cold storage tank 13, and the cold storage pump 3; the first cold release pump 2 is installed on the refrigeration unit return pipe between the chilled water return pipe 12 and the return port of the refrigeration unit 1; the cold storage pump 3 is installed on the cold storage hot end pipe branch between the refrigeration unit 1 and the hot end pipe section of the remote cold storage tank 13; and the second cold release pump 4 is installed on the cold release cold end pipe branch between the chilled water supply pipe 11 and the cold end pipe section of the remote cold storage tank 13. The top of the remote cold storage tank 13 is connected to a remote expansion assembly 13-1, which is used to accommodate the volume change caused by the temperature difference of the chilled water in the remote cold storage tank 13 after cold storage and release, and to balance the hydraulic pressure between the pipelines.

[0038] In one or more embodiments of the present invention, the distal expansion assembly 13-1 is cylindrical, including a distal expansion tank 13-6, and its radius... Determined by the following formula:

[0039]

[0040]

[0041] in, For the volume of the distal expansion tank 13-6, The preset height for the distal expansion tank 13-6, α The coefficient of thermal expansion of chilled water is denoted as . For the volume of the remote cold storage tank 13, The density of the chilled water before cooling. This is the density of the chilled water after cooling.

[0042] Since the volume change of the chilled water in the remote cold storage tank 13 is caused by the temperature difference after cold storage and cold release, the radius of the remote expansion tank 13-6 can be accurately calculated using the above formula. This can prevent chilled water from overflowing, avoid water waste, and reduce the cold loss of the air conditioning system.

[0043] like Figure 2As shown, the present invention also provides a cold storage tank structure with an expansion device, applied to user terminal heat exchange, including a refrigeration unit 1, a first cold release pump 2, a cold storage pump 3, a second cold release pump 4, a chilled water supply pipe 11, a chilled water return pipe 12, a remote cold storage tank 13, and a near-end cold storage tank 14. The refrigeration unit 1, chilled water supply pipe 11, user terminal, chilled water return pipe 12, and first cold release pump 2 are sequentially connected to form a refrigeration unit cold release circuit. The remote cold storage tank 13, second cold release pump 4, chilled water supply pipe 11, user terminal, and chilled water return pipe 12 are sequentially connected to form a remote cold storage tank cold release circuit. The near-end cold storage tank 14, second cold release pump 4, chilled water supply pipe 11, user terminal, and user terminal are sequentially connected to form a remote cold storage tank cold release circuit. The chilled water return pipe 12 and the remote cold storage tank 13 are connected in sequence to form a cold release circuit. The chiller unit 1, the remote cold storage tank 13 and the cold storage pump 3 are connected in sequence to form a cold storage circuit. The chiller unit 1, the remote cold storage tank 14 and the cold storage pump 3 are connected in sequence to form a cold storage circuit. The first cold release pump 2 is installed on the chiller unit return pipe between the chilled water return pipe 12 and the return port of the chiller unit 1. The cold storage pump 3 is installed on the cold storage hot end pipe branch between the chiller unit 1 and the hot end pipe section of the remote cold storage tank 13. The second cold release pump 4 is installed on the cold release cold end pipe branch between the chilled water supply pipe 11 and the cold end pipe section of the remote cold storage tank 13. The top of the distal cold storage tank 13 is connected to a distal expansion assembly 13-1, which is used to accommodate the volume change of the chilled water in the distal cold storage tank 13 due to the temperature difference after cold storage and release, and to balance the hydraulic pressure between the various pipelines; the top of the proximal cold storage tank 14 is connected to a proximal expansion assembly 14-1, which is used to accommodate the volume change of the chilled water in the proximal cold storage tank 14 due to the temperature difference after cold storage and release, and to balance the hydraulic pressure between the various pipelines.

[0044] In an embodiment of the present invention, a valve assembly is further provided on the pipeline, specifically including: a remote hot end valve 13-3, a proximal hot end valve 14-3, a remote cold end valve 13-4, and a proximal cold end valve 14-4. The remote hot end valve 13-3 and the proximal hot end valve 14-3 are respectively provided on the hot end pipe sections of the remote cold storage tank 13 and the proximal cold storage tank 14, and the remote cold end valve 13-3 and the proximal cold end valve 13-4 are respectively provided on the cold end pipe sections of the remote cold storage tank 13 and the proximal cold storage tank 14. The valve assembly further includes a first electric valve 5, a second electric valve 6, a third electric valve 7, a fourth electric valve 8, a fifth electric valve 9, and a sixth electric valve 10. The first electric valve 5 is installed on the water supply pipe of the refrigeration unit 1, the second electric valve 6 is installed on the water return pipe of the refrigeration unit 1, the third electric valve 7 is installed on the branch pipe of the cold storage hot end section, the fourth electric valve 8 is installed on the branch pipe of the cold storage cold end section, the fifth electric valve 9 is installed on the branch pipe of the cold release hot end section, and the sixth electric valve 10 is installed on the branch pipe of the cold storage cold end section.

[0045] The cooling rate of different cold storage tanks can be kept consistent by adjusting the opening of the valves. At the same time, different pipeline switching can be achieved by setting the first electric valve 5, the second electric valve 6, the third electric valve 7, the fourth electric valve 8, the fifth electric valve 9 and the sixth electric valve 10.

[0046] like Figure 3 As shown, in one or more embodiments of the present invention, the distal expansion assembly 13-1 includes a distal expansion tank 13-6, the bottom of which is connected to the internal space of the distal cold storage tank 13, for accommodating the volume change caused by the temperature difference of the chilled water in the distal cold storage tank 13 after cold storage and cold release. like Figure 4 As shown, the proximal expansion assembly 14-1 includes a proximal expansion tank 14-6 and a proximal expansion tube 14-5. The bottom of the proximal expansion tank 14-6 is connected to the internal space of the proximal cold storage tank 14 and is used to accommodate the volume change caused by the temperature difference of the chilled water in the proximal cold storage tank 14 after cold storage and cold release. The proximal expansion tube 14-5 is connected and disposed above the proximal expansion tank 13-6 and is used to balance the unbalanced resistance between the distal cold storage tank 13 and the proximal cold storage tank 14.

[0047] By setting up a remote expansion tank 13-6 and a near-end expansion tank 14-6, the volume change caused by the temperature difference between the chilled water in the cold storage tank after storage and release can be accommodated, that is, the expansion of the chilled water in the cold storage tank. Furthermore, by setting up the near-end expansion pipe 14-5, the unbalanced resistance value between the remote cold storage tank 13 and the near-end cold storage tank 14 can be balanced, that is, the additional friction resistance and local resistance of the remote cold storage tank 13 compared to the near-end cold storage tank 14 can be stored, thereby further preventing chilled water from overflowing.

[0048] In one or more embodiments of the present invention, the distal expansion tank 13-6 is cylindrical, and its radius is... Determined by the following formula:

[0049]

[0050]

[0051] in, For the volume of the distal expansion tank 13-6, The preset height of the distal expansion tank 13-6 (1m in the embodiment of the present invention). α The coefficient of thermal expansion of chilled water is denoted as . For the volume of the remote cold storage tank 13, The density of the chilled water before cooling. This is the density of the chilled water after cooling. The proximal expansion tank 14-6 is cylindrical, and its radius is... Determined by the following formula:

[0052]

[0053]

[0054] in, For the volume of the proximal expansion tank 14-6, The preset height of the near-end expansion tank 14-6 (1m in the embodiment of the present invention). α The coefficient of thermal expansion of chilled water is denoted as . The volume of the near-end cold storage tank 14, The density of the chilled water before cooling. This is the density of the chilled water after cooling.

[0055] Since the temperature difference between the chilled water in the remote cold storage tank 13 and the near cold storage tank 14 after cold storage and cold release will cause volume changes, the radius of the remote expansion tank 13-6 and the near expansion tank 14-6 can be accurately calculated using the above formula. This can prevent chilled water from overflowing, avoid water waste, and reduce the cooling loss of the air conditioning system.

[0056] It should be noted that, in this invention, after calculating the radius of the near-end expansion tank 14-6, the actual value of the radius of the near-end expansion tank 14-6 can be taken as the nominal diameter that is slightly larger than the calculated value.

[0057] In one or more embodiments of the present invention, the proximal expansion tube 14-5 is tubular, and its height Determined by the following formula:

[0058]

[0059]

[0060]

[0061]

[0062] in, β This is the margin coefficient (taken as 0.5 in this embodiment). ab The pipe section refers to the additional return water pipe section that the distal cold storage tank 13 passes through compared to the proximal cold storage tank 14. a Point is the return water pipe ab The branching point of the pipe section, b The point is the end point of the additional straight pipe section that the distal cold storage tank 13 traverses compared to the proximal cold storage tank 14. cd The pipe section refers to the additional water supply pipe section that the distal cold storage tank 13 passes through compared to the proximal cold storage tank 14. c Point for cd The confluence point of the pipe section, d The point is the starting point of the additional straight pipe section that the distal cold storage tank 13 traverses compared to the proximal cold storage tank 14. The unbalanced resistance value between the distant cold storage tank 13 and the near-end cold storage tank 14 under cold storage conditions. The unbalanced resistance value between the far-end cold storage tank 13 and the near-end cold storage tank 14 under cooling conditions The larger one, for ab The unbalanced resistance value of the pipe section, for ab Friction resistance along the pipe section, for a Point and b The sum of the local resistances of the corresponding resistance components at the point. for a The point corresponds to the local resistance of the resistance component. for ab The frictional resistance coefficient of the pipe section, for ab The length of the pipe section for ab The diameter of the pipe section, The density of chilled water, For the rate of chilled water, for a Point and b The sum of the local resistance coefficients of the corresponding resistance components at the point. for a The local resistance coefficient of the resistance component at the point. for ab Specific friction resistance of the pipe section. Considering practical engineering practices, the minimum pipe diameter for the distal expansion pipe 13-5 and the proximal expansion pipe 14-5 can be DN100.

[0063] In a system of multiple cold storage tanks, the cold storage tank farther from the confluence point experiences greater frictional resistance, which can cause an imbalance in water level between the tanks. Calculating the additional imbalance resistance between the far-end and near-end cold storage tanks can be used to accurately determine the height of the near-end expansion tube 14-5. By configuring expansion tubes for each cold storage tank according to the height of the most unfavorable expansion device, it is possible to ensure that chilled water does not overflow during both cooling and cold storage conditions, while also standardizing processing, controlling costs, and maximizing safety.

[0064] In an embodiment of the present invention, during cold storage, the flow rate of each cold storage tank in the remote cold storage tank 13 and the near cold storage tank 14 is half of the flow rate of the cold storage pump 3 under operating conditions; during cold release, the flow rate of each cold storage tank in the remote cold storage tank 13 and the near cold storage tank 14 is half of the flow rate of the cold release pump 4 under operating conditions, and the flow rates under cold storage and cold release conditions are equal.

[0065] Optionally, in one or more embodiments of the present invention, if If <0, then the distal expansion assembly 13-1 further includes a distal expansion tube 13-5, which is connected above the distal expansion tank 13-6 to balance the unbalanced resistance between the distal cold storage tank 13 and the proximal cold storage tank 14.

[0066] If the calculated unbalanced resistance value between the remote cold storage tank 13 and the near-end cold storage tank 14 is less than 0, it indicates that the chilled water in the remote expansion tank 13-6 may overflow. Therefore, installing the remote expansion pipe 13-5 can completely prevent the chilled water from overflowing in extreme cases.

[0067] In one or more embodiments of the present invention, the height of the distal expansion tube 13-5 is At this point, considering standardized processing, better cost control, and maximum safety, the proximal expansion assembly 14-1 is also equipped with a height of [missing information]. The proximal expansion tube 14-5.

[0068] In one or more embodiments of the present invention, the number of the proximal cold storage tanks 14 is plurality of, and the height of the proximal expansion tubes 14-5 is determined by the following method: First, determine the height of the proximal expansion tube 14-5 of the proximal cold storage tank 14, which is closest to the distal cold storage tank 13, according to the calculation formula. Then, based on the height of the proximal expansion tube 14-5 of the proximal cold storage tank 14 that is closest to the distal cold storage tank 13, the height of the proximal expansion tube 14-5 of the second closest proximal cold storage tank 14 to the distal cold storage tank 13 is calculated, and so on, until the height of the proximal expansion tube 14-5 of the proximal cold storage tank 14 that is farthest from the distal cold storage tank 13 is calculated. Finally, the expansion tube heights are unified to the maximum value of all expansion tube heights.

[0069] When there are multiple near-end cold storage tanks 14, the height of the proximal expansion tube 14-5 of the nearest near-end cold storage tank 14 can be calculated first for the far-end cold storage tank 13 and the nearest near-end cold storage tank 14. Then, the two are treated as a whole and calculated together with the proximal expansion tube 14-5 of the next nearest near-end cold storage tank 14 to obtain the height of the proximal expansion tube 14-5 of the next nearest near-end cold storage tank 14. In this way, the height of the proximal expansion tube 14-5 of each near-end cold storage tank 14 can be calculated. Finally, the expansion tube height is unified to the maximum value of all expansion tube heights to meet more application scenarios and enhance its versatility.

[0070] The following explanation uses two cold storage tanks as examples: In this invention, the aforementioned parameters are taken as follows:

[0071]

[0072]

[0073]

[0074]

[0075]

[0076] According to the table, at a temperature of 5℃, the kinematic viscosity is... At a temperature of 10℃, the kinematic viscosity In this embodiment, the supply and return water temperatures are respectively , and The heights of the distal cold storage tank 13 and the proximal cold storage tank 14 are respectively. and The radii of the distant cold storage tank 13 and the near-end cold storage tank 14 are respectively. and

[0077] These represent the flow rates through pipes ab and cd, respectively. The flow rate is given under certain operating conditions, and the pump flow rates are equal under both cold storage and cold release conditions.

[0078] Based on the above data, the volumes of the distal expansion tank 13-6 and the proximal expansion tank 14-6 can be calculated first, specifically as follows:

[0079] When the height of the distal expansion tank is 13-6 Height of the near-end expansion tank 14-6 When the diameter is 1m, the required diameter can be calculated:

[0080] At this point, DN1700 can be used as the distal expansion tank 13-6 and the proximal expansion tank 14-6 in this case.

[0081] Next, calculate the unbalanced resistance value between the far-end cold storage tank 13 and the near-end cold storage tank 14, and determine the dimensions of the far-end expansion pipe 1-5 and the near-end expansion pipe 2-5. This calculation takes the cold storage condition as an example, and the specific implementation is as follows: For cold storage operation, chilled water at 10°C enters chiller unit 1 through pipe section ab, is processed by chiller unit 1 to 5°C, and then returns to the cold storage tank through pipe section cd. Therefore, regarding the resistance of pipe section ab:

[0082] The flow is in a turbulent state at this point. The specific frictional resistance at this time can be obtained by consulting relevant documents. Therefore, we can obtain :

[0083] This represents the additional frictional resistance lost by the chilled water in the far-end cold storage tank 13 compared to the chilled water in the near-end cold storage tank 14.

[0084] For local resistance In this embodiment, there is only one tee and a 90° welded elbow. The calculated local resistance coefficient is: Therefore, it can be calculated that :

[0085] This indicates the local resistance of the remote cold storage tank 13 in the ab pipe section.

[0086] Regarding the resistance of pipe segment cd, since the calculated flow is also turbulent, the same resistance value can be obtained. Therefore:

[0087]

[0088] Since the near-end cold storage tank 14 has relatively no frictional resistance, but only local resistance at one point. Its drag coefficient is Therefore:

[0089] The difference in resistance values ​​can be calculated from the above:

[0090] Furthermore, after considering a 50% margin factor, the height of the proximal expansion tube 14-5 can be calculated:

[0091] When we calculate using the method described above, if Then we need to install a distal expansion tube 13-5, the height of which is Furthermore, to ensure standardized processing, better cost control, and maximum safety, all expansion tanks and expansion pipes of the cold storage tanks are installed according to the specifications calculated based on the most unfavorable unbalanced resistance value. Specifically, both the far-end cold storage tank 13 and the near-end cold storage tank 14 are installed with DN100 expansion tubes and a height of [missing information]. Expansion tube.

[0092] like Figure 5 The diagram shows the structure of three cold storage tanks. Starting from the farthest tank (13) and moving closer, the same calculation method is used for the farthest cold storage tank 13 and the middle near-end cold storage tank 14, with a slight difference: the flow rate is one-third of the original flow rate. After calculating the resistance difference between the farthest cold storage tank 13 and the middle near-end cold storage tank 14, the height of the near-end expansion pipe 14-5 of the middle near-end cold storage tank 14 without any margin is obtained. Then, the unbalanced resistance between the nearest near-end cold storage tank 14 and the middle cold storage tank 14 is calculated using the same method. Therefore, the height of the near-end expansion pipe 14-5 of the nearest cold storage tank 14 can be designed.

[0093] Finally, also for the sake of standardized processing, better cost control, and ensuring safety as much as possible, all cold storage tanks will be installed with a DN100 diameter and a height of [missing information]. The expansion tube. Similarly, for systems with more cold storage tanks, we can design them using the same method.

[0094] The present invention relates to a cold storage tank structure with an expansion device. By designing an expansion device, overflowing chilled water is stored within the expansion device. This system features an expansion device at the top of the cold storage tank, resulting in a simple structure, stable and reliable operation, and low cost. It effectively solves the problem of volume changes in chilled water before and after storage and release, and also addresses the issue of resistance imbalance between cold storage tanks, preventing overflow. This ensures the low-carbon and energy-saving operation of the cold storage air conditioning system and is suitable for the retrofitting of existing cold storage tank systems and new construction projects. The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A cold storage tank structure with an expansion device, used for heat exchange in a user terminal, characterized in that: The system includes a refrigeration unit (1), a first cooling pump (2), a cold storage pump (3), a second cooling pump (4), a chilled water supply pipe (11), a chilled water return pipe (12), and a remote cold storage tank (13). The refrigeration unit (1), chilled water supply pipe (11), user terminal, chilled water return pipe (12), and first cooling pump (2) are sequentially connected to form a refrigeration unit cooling circuit. The remote cold storage tank (13), second cooling pump (4), chilled water supply pipe (11), user terminal, and chilled water return pipe (12) are sequentially connected to form a remote cold storage tank cooling circuit. The unit (1), the remote cold storage tank (13) and the cold storage pump (3) are connected in sequence to form a cold storage circuit of the remote cold storage tank; the first cold release pump (2) is set on the return water pipe of the refrigeration unit between the chilled water return pipe (12) and the return water port of the refrigeration unit (1); the cold storage pump (3) is set on the cold storage hot end pipe branch between the refrigeration unit (1) and the hot end pipe section of the remote cold storage tank (13); and the second cold release pump (4) is set on the cold release cold end pipe branch between the chilled water supply pipe (11) and the cold end pipe section of the remote cold storage tank (13). The top of the remote cold storage tank (13) is connected to a remote expansion assembly (13-1) to accommodate the volume change caused by the temperature difference between the chilled water in the remote cold storage tank (13) after cold storage and cold release, and to balance the hydraulic pressure between the pipelines.

2. The cold storage tank structure with an expansion device according to claim 1, characterized in that: The distal expansion assembly (13-1) is cylindrical, including a distal expansion tank (13-6), and its radius... Determined by the following formula: ； ； ； in, For the volume of the distal expansion tank (13-6), The preset height for the remote expansion tank (13-6) α The coefficient of thermal expansion of chilled water is denoted as . For the volume of the remote cold storage tank (13), The density of the chilled water before cooling. This is the density of the chilled water after cooling.

3. A cold storage tank structure with an expansion device, used for heat exchange at a user terminal, characterized in that: The system includes a refrigeration unit (1), a first cold release pump (2), a cold storage pump (3), a second cold release pump (4), a chilled water supply pipe (11), a chilled water return pipe (12), a remote cold storage tank (13), and a near-end cold storage tank (14). The refrigeration unit (1), chilled water supply pipe (11), user terminal, chilled water return pipe (12), and first cold release pump (2) are sequentially connected to form a refrigeration unit cold release circuit. The remote cold storage tank (13), second cold release pump (4), chilled water supply pipe (11), user terminal, and chilled water return pipe (12) are sequentially connected to form a remote cold storage tank cold release circuit. The near-end cold storage tank (14), second cold release pump (4), chilled water supply pipe (11), user terminal, and chilled water return pipe (12) are sequentially connected to form a remote cold storage tank cold release circuit. A near-end cold storage tank cold release circuit is formed. The refrigeration unit (1), the far-end cold storage tank (13) and the cold storage pump (3) are connected in sequence to form a far-end cold storage tank cold storage circuit. The refrigeration unit (1), the near-end cold storage tank (14) and the cold storage pump (3) are connected in sequence to form a near-end cold storage tank cold storage circuit. The first cold release pump (2) is set on the refrigeration unit return water pipe between the chilled water return pipe (12) and the return water port of the refrigeration unit (1). The cold storage pump (3) is set on the cold storage hot end pipe branch between the refrigeration unit (1) and the hot end pipe section of the far-end cold storage tank (13). The second cold release pump (4) is set on the cold release cold end pipe branch between the chilled water supply pipe (11) and the cold end pipe section of the far-end cold storage tank (13). The top of the far-end cold storage tank (13) is connected to a far-end expansion assembly (13-1) to accommodate the volume change caused by the temperature difference between the chilled water in the far-end cold storage tank (13) after cold storage and cold release, and to balance the hydraulic pressure between the various pipelines; the top of the near-end cold storage tank (14) is connected to a near-end expansion assembly (14-1) to accommodate the volume change caused by the temperature difference between the chilled water in the near-end cold storage tank (14) after cold storage and cold release, and to balance the hydraulic pressure between the various pipelines.

4. The cold storage tank structure with an expansion device according to claim 3, characterized in that: The distal expansion assembly (13-1) includes a distal expansion tank (13-6), the bottom of which is connected to the internal space of the distal cold storage tank (13) to accommodate the volume change caused by the temperature difference of the chilled water in the distal cold storage tank (13) after cold storage and cold release. The proximal expansion assembly (14-1) includes a proximal expansion tank (14-6) and a proximal expansion tube (14-5). The bottom of the proximal expansion tank (14-6) is connected to the internal space of the proximal cold storage tank (14) to accommodate the volume change caused by the temperature difference of the chilled water in the proximal cold storage tank (14) after cold storage and cold release. The proximal expansion tube (14-5) is connected above the proximal expansion tank (13-6) to balance the unbalanced resistance between the distal cold storage tank (13) and the proximal cold storage tank (14).

5. The cold storage tank structure with an expansion device according to claim 4, characterized in that: The distal expansion tank (13-6) is cylindrical, and its radius... Determined by the following formula: ； ； ； in, For the volume of the distal expansion tank (13-6), The preset height for the remote expansion tank (13-6) α The coefficient of thermal expansion of chilled water is denoted as . For the volume of the remote cold storage tank (13), The density of the chilled water before cooling. This is the density of the chilled water after cooling. The proximal expansion tank (14-6) is cylindrical, and its radius... Determined by the following formula: ； ； ； in, The volume of the proximal expansion tank (14-6) This is the preset height for the near-end expansion tank (14-6). α The coefficient of thermal expansion of chilled water is denoted as . For the volume of the near-end cold storage tank (14), The density of the chilled water before cooling. This is the density of the chilled water after cooling.

6. The cold storage tank structure with an expansion device according to claim 4, characterized in that: The proximal expansion tube (14-5) is tubular, and its height... Determined by the following formula: ； ； ； ； ； in, β This is the residual coefficient. ab The pipe section refers to the additional return water pipe section that the distal cold storage tank (13) passes through compared to the proximal cold storage tank (14). a Point is the return water pipe ab The branching point of the pipe section, b The point is the end point of the additional straight pipe section that the distal cold storage tank (13) traverses compared to the proximal cold storage tank (14). cd The pipe section refers to the additional water supply pipe section that the distal cold storage tank (13) passes through compared to the proximal cold storage tank (14). c Point for cd The confluence point of the pipe section, d The point is the starting point of the additional straight pipe section that the distal cold storage tank (13) passes through compared to the proximal cold storage tank (14). The unbalanced resistance value between the far-end cold storage tank (13) and the near-end cold storage tank (14) under cold storage conditions. The unbalanced resistance value between the far-end cold storage tank (13) and the near-end cold storage tank (14) under the cooling condition. The larger one, for ab Unbalanced resistance value of the pipe section for ab Friction resistance along the pipe section, for a Point and b The sum of the local resistances of the corresponding resistance components at the point. for a The point corresponds to the local resistance of the resistance component. for ab The frictional resistance coefficient of the pipe section, for ab The length of the pipe section for ab The diameter of the pipe section, The density of chilled water, The flow rate of the chilled water. for Point and b The sum of the local resistance coefficients of the corresponding resistance components at the point. for a The local resistance coefficient of the resistance component at the point. for ab Specific friction of the pipe section.

7. The cold storage tank structure with an expansion device according to claim 6, characterized in that: like If <0, the distal expansion assembly (13-1) further includes a distal expansion tube (13-5), which is connected above the distal expansion tank (13-6) to balance the unbalanced resistance between the distal cold storage tank (13) and the proximal cold storage tank (14).

8. The cold storage tank structure with an expansion device according to claim 7, characterized in that: The height of the distal expansion tube (13-5) is .

9. The cold storage tank structure with an expansion device according to any one of claims 3-8, characterized in that: The number of the near-end cold storage tanks (14) is multiple, and the height of the near-end expansion tubes (14-5) is determined by the following method: First, determine the height of the proximal expansion tube (14-5) of the proximal cold storage tank (14) that is closest to the distal cold storage tank (13) according to the calculation formula described in claim 6; Then, based on the height of the proximal expansion tube (14-5) of the proximal cold storage tank (14) that is closest to the distal cold storage tank (13), calculate the height of the proximal expansion tube (14-5) of the proximal cold storage tank (14) that is next to the distal cold storage tank (13), and so on, until the height of the proximal expansion tube (14-5) of the proximal cold storage tank (14) that is furthest from the distal cold storage tank (13) is calculated. Finally, unify the height of all expansion tubes to the height of the expansion tube with the largest height.

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