Refrigeration system and method of adding and draining refrigerant

Abstract

The present application relates to the technical field of refrigeration, and discloses a refrigeration system and a method for charging and discharging the refrigeration system. The refrigeration system comprises a circulation module, a charging and discharging module and an expansion compensation module. The circulation module comprises a circulation pipeline, which is sequentially connected with a load, a circulation pump and a one-way valve. The circulation pipeline is filled with a heat-conducting medium, which is used for cooling the load. The charging and discharging module is connected to the pipeline between the load and the one-way valve. The expansion compensation module is in communication with the suction side pipeline of the circulation pump, and a part of the heat-conducting medium is stored in the expansion compensation module, which is used for compensating the volume fluctuation of the heat-conducting medium in the circulation module. The refrigeration system and the method for charging and discharging the refrigeration system can actively compensate the volume fluctuation of the medium by the expansion compensation module, can avoid the abnormal pressure or cavitation phenomenon of the refrigeration system, can ensure the stability of the volume flow and pressure in the circulation module, and can further ensure the continuity and reliability of cooling the load.

Description

Technical Field

[0001] This invention relates to the field of refrigeration technology, and in particular to a refrigeration system and a method for adding and draining liquid therefrom. Background Technology

[0002] In the field of refrigeration system technology, heat transfer medium circulation systems are widely used in the temperature control processes of various industrial equipment, experimental devices, and precision instruments. Traditional refrigeration systems typically use a circulating pump to drive the heat transfer medium to circulate in pipelines, flowing through the load area to achieve heat exchange and cooling.

[0003] In the design and application of refrigeration systems, the stability, energy efficiency, and economy of system operation largely depend on the system's ability to compensate for fluctuations in the volume of its internal heat transfer medium and the convenience and thoroughness of its filling and draining operations. Traditional refrigeration systems typically employ fixed-volume tank structures to cope with the thermal expansion and contraction of the medium. However, in practical engineering, the tank volume of such systems often relies on empirical estimations or rough calculations, lacking precise matching with key parameters of the target load and the physical properties of the heat transfer medium. This often results in an unreasonable tank volume: too small a volume leads to insufficient compensation capacity, causing abnormal system pressure, cavitation, or unstable flow; too large a volume increases equipment costs, expands the footprint, and raises energy consumption, resulting in resource waste. This contradiction is particularly prominent in diverse application scenarios, ranging from small laboratory testing equipment to large industrial lasers and injection molding machines, becoming a key bottleneck restricting the balance between energy efficiency and operating costs in refrigeration systems.

[0004] Furthermore, during the renovation, upgrading, or evaluation and reuse of existing refrigeration systems, engineers often struggle to quickly and accurately determine whether the capacity of the existing refrigeration system is suitable for the new or changed load. Incorrect decisions can either result in insufficient refrigeration system capacity affecting the normal operation of the new load, or excessive refrigeration system capacity leading to idle equipment and wasted investment. Summary of the Invention

[0005] Therefore, the purpose of this invention is to overcome the system instability problem caused by the volume fluctuation of the heat transfer medium in the operation of the refrigeration system in the prior art, and to provide a refrigeration system and its liquid addition and drainage method. By actively compensating for the volume fluctuation of the medium through the expansion compensation module, the abnormal pressure or cavitation phenomenon of the refrigeration system can be avoided, ensuring the stability of the volume flow rate and pressure in the circulation module, thereby ensuring the continuity and reliability of cooling the load.

[0006] To address the aforementioned technical problems, this invention provides a refrigeration system, comprising: a circulation module including a circulation pipeline sequentially connected to a load, a circulation pump, and a one-way valve; the circulation pipeline is filled with a heat-conducting medium for cooling the load; a loading and unloading module connected to the pipeline between the load and the one-way valve; and an expansion compensation module connected to the suction side pipeline of the circulation pump, the expansion compensation module storing a portion of the heat-conducting medium to compensate for volume fluctuations of the heat-conducting medium in the circulation module; the loading and unloading module includes: a dual-purpose loading and unloading tank; and a ninth pipe. The ninth pipeline has a first end connected to the dual-purpose filling and draining tank and extends into the bottom of the tank; the second end of the ninth pipeline is connected to the pipeline between the load and the one-way valve; a power switching device is configured to selectively apply positive or negative pressure to the dual-purpose filling and draining tank; wherein, when positive pressure is applied, the dual-purpose filling and draining tank is configured to fill the circulation module and the expansion compensation module with heat-conducting medium; when negative pressure is applied, the dual-purpose filling and draining tank is configured to recover the heat-conducting medium from the circulation module and the expansion compensation module.

[0007] Preferably, the volume of the expansion compensation module is configured to be greater than the sum of the system stagnation volume, the system thermal expansion compensation volume, and the system dynamic buffer volume; wherein, the system stagnation volume is configured to include at least the amount of heat-conducting medium charged in the pipeline and components from the suction side of the circulating pump to the one-way valve; the system thermal expansion compensation volume is configured to be the volume fluctuation of the heat-conducting medium in the load; and the system dynamic buffer volume is configured to be the product of the volumetric flow rate in the circulating pipeline and the preset buffer time.

[0008] Preferably, the expansion compensation module includes: a circulation tank containing a heat-conducting medium, the circulation tank being connected to a second pipeline of the circulation pipeline, a first end of the second pipeline extending into the bottom of the circulation tank, and a second end of the second pipeline connected to the outlet of the load; an expansion level tank having a breather valve at its top, and containing a portion of the heat-conducting medium; and a first pipeline, a first end of which is connected to the expansion level tank and extends into the bottom of the expansion level tank, and a second end of which is connected to the top of the circulation tank.

[0009] Preferably, the volume of the circulation tank is configured to be greater than the sum of the system stagnant volume and the system dynamic buffer volume; the volume of the expansion level tank is configured to be greater than or equal to the system thermal expansion compensation volume.

[0010] Preferably, the power switching device includes: a vacuum generator, wherein the charging end of the vacuum generator is connected to a compressed air source, the exhaust end of the vacuum generator is connected to the atmospheric environment, and the vacuum generating end of the vacuum generator is connected to the top of the liquid filling and discharging tank.

[0011] Preferably, the addition / discharge module further includes: a maintenance manual valve, which is connected in parallel with the check valve; and a liquid addition / discharge manual valve, which is installed on the ninth pipeline.

[0012] Preferably, the dual-purpose tank for adding and discharging liquid is equipped with: a feeding valve connected to a heat transfer medium source; a discharge valve connected to a medium recovery device; and a pressure relief valve connected to the atmospheric environment.

[0013] On the other hand, the present invention provides a method for adding and draining liquid in a refrigeration system, comprising the steps of: when liquid needs to be added: turning off the venting function of the adding and draining module to apply positive pressure to the adding and draining liquid dual-purpose tank of the adding and draining module; under the positive pressure drive, the heat-conducting medium in the adding and draining liquid dual-purpose tank is forced into the circulation module and the expansion compensation module until the liquid level in the expansion compensation module reaches a first preset position; wherein, the first preset position is determined according to the volume of the expansion liquid level tank in the compensation module and the volume fluctuation of the heat-conducting medium in the circulation pipeline; when liquid needs to be drained: turning on the venting function of the adding and draining module to apply negative pressure to the adding and draining liquid dual-purpose tank of the adding and draining module; under the negative pressure suction, the heat-conducting medium in the circulation module and the expansion compensation module is recovered to the adding and draining liquid dual-purpose tank until no heat-conducting medium flows out of the recovery flow path.

[0014] The above-described technical solution of the present invention has the following beneficial effects compared with the prior art.

[0015] The refrigeration system described in this invention achieves forced circulation of the heat transfer medium through a circulation module, ensuring continuous cooling of the load. By connecting the filling and draining modules to the circulation loop, the filling and draining operations do not require modification of the main circulation pipeline, facilitating daily maintenance and medium replacement of the refrigeration system. The expansion compensation module actively compensates for fluctuations in medium volume, avoiding abnormal pressure or cavitation in the refrigeration system and ensuring the stability of volumetric flow rate and pressure within the circulation module, thereby guaranteeing the continuity and reliability of cooling the load.

[0016] The liquid addition and drainage method described in this invention achieves the liquid addition and drainage process through pressure drive and valve control, resulting in fast operation and simple operation, facilitating fully automatic liquid addition and drainage control. Furthermore, the liquid addition endpoint is determined by the expansion compensation module reaching a first preset level, ensuring the reliability of the filling volume; the liquid drainage endpoint is determined by the absence of heat-conducting medium flowing out of the recovery flow path, ensuring thorough recovery. This method not only guarantees consistent operational results but also reduces reliance on operator experience, minimizes labor input, and improves operational safety. Attached Figure Description

[0017] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0018] Figure 1 This is a schematic diagram of a refrigeration system in one embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of another structure of the refrigeration system in one embodiment of the present invention.

[0020] Figure 3 This is a schematic flowchart of a liquid addition and drainage method in one embodiment of the present invention.

[0021] Explanation of reference numerals in the accompanying drawings: 1. Expansion compensation module; 11. Circulation tank; 12. Expansion level tank; 121. Breathing valve; 3. Circulation pump; 4. Check valve; 5. Circulation pipeline; 51. First pipeline; 52. Second pipeline; 53. Third pipeline; 54. Fourth pipeline; 57. Seventh pipeline; 58. Eighth pipeline; 59. Ninth pipeline; 591. First mounting interface; 592. Second mounting interface; 7. Evaporator; 8. Load; 9. Addition and drainage module; 91. Vacuum generator; 911. Inflation end; 912. Exhaust end; 913. Vacuum generating end; 921. Inspection valve; 922. Addition and drainage valve; 93. Dual-purpose tank for adding and draining liquids; 931. Pressure relief valve. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0023] In order to overcome the system instability problem caused by the volume fluctuation of the heat transfer medium during the operation of the refrigeration system in the prior art, and to solve the problems of incomplete venting and incomplete liquid drainage in the prior art, the present invention provides a refrigeration system and a liquid filling and drainage method thereof.

[0024] Example 1: This embodiment of the invention discloses a refrigeration system, including: a circulation module, an exhaust module 9, and an expansion compensation module 1.

[0025] In application, the circulation module is filled with a heat-conducting medium (such as water, fluorinated liquid, etc.) and circulated as a cold source. The circulation module achieves forced circulation of the heat-conducting medium, ensuring continuous cooling of load 8. Furthermore, the expansion compensation module 1 is connected to the circulation module and stores a portion of the heat-conducting medium to compensate for volume fluctuations in the circulation module. By actively compensating for medium volume fluctuations, the expansion compensation module 1 avoids abnormal pressure or cavitation in the refrigeration system, ensuring stable flow rate and pressure within the circulation module, thereby guaranteeing the continuity and reliability of cooling load 8. Additionally, the addition and drainage module 9 is connected to the circulation module and is used to add or recover heat-conducting medium from the circulation module and expansion compensation module 1 by switching the internal pressure state of the addition and drainage module 9. This allows for liquid addition and drainage operations without modifying the main circulation pipeline 5, facilitating routine maintenance and medium replacement of the refrigeration system.

[0026] In practical applications, the average height of the expansion module 9 is lower than the average height of the circulation module, and the average height of the circulation module is lower than the average height of the expansion compensation module 1.

[0027] The circulation module of the present invention includes a circulation pipeline 5 filled with a heat-conducting medium and components on the circulation pipeline 5. The heat-conducting medium is used to cool the load 8, which can be replaced according to user requirements. The type of heat-conducting medium can be adjusted according to the temperature variation range required by the load 8, such as water, fluorinated liquid, etc.

[0028] When applying, refer to Figure 1 and Figure 2 The components on the circulation line 5 include, in sequence, a circulation pump 3, a check valve 4, and a load 8. Further, refer to... Figure 2 An evaporator 7, such as a heat exchanger, is also provided between the one-way valve 4 and the load 8.

[0029] In practical applications, the circulation pipeline 5 includes a second pipeline 52, a third pipeline 53, a fourth pipeline 54, a seventh pipeline 57, and an eighth pipeline 58. Specifically, the first end of the second pipeline 52 is connected to the expansion compensation module 1 and inserted into its bottom; the second end of the second pipeline 52 is connected to the outlet of the load 8. The first end of the third pipeline 53 is connected to the bottom of the expansion compensation module 1; the second end of the third pipeline 53 is connected to the suction side of the circulation pump 3. The first end of the fourth pipeline 54 is connected to the discharge side of the circulation pump 3; the second end of the fourth pipeline 54 is connected to a one-way valve 4. The first end of the seventh pipeline 57 is connected to the one-way valve 4; the second end of the seventh pipeline 57 is connected to the evaporator 7. The first end of the eighth pipeline 58 is connected to the evaporator 7; the second end of the eighth pipeline 58 is connected to the inlet of the load 8.

[0030] In actual implementation, when the circulation pump 3 and the one-way valve 4 are opened, the heat transfer medium in the expansion compensation module 1 participates in the circulation process of the circulation module. The heat transfer medium in the circulation module flows clockwise, that is, it circulates along the direction of the third pipeline 53, circulation pump 3, fourth pipeline 54, one-way valve 4, seventh pipeline 57, evaporator 7, eighth pipeline 58, load 8, second pipeline 52, and third pipeline 53.

[0031] During system operation, when the heat transfer medium expands due to increased temperature, the excess medium is discharged into the expansion compensation module 1 through the second pipe 52. If the heat transfer medium contains air or gas is generated due to local vaporization, the gas-liquid mixture will be separated by gravity in the expansion compensation module 1. The separated gas is discharged into the atmosphere or a recovery device through a valve at the top of the expansion compensation module 1, while the liquid heat transfer medium is stored in the lower part of the expansion compensation module 1 and continues to participate in the circulation of the circulation module.

[0032] When the system is running, if the volume of the heat transfer medium shrinks due to the decrease in temperature, the liquid heat transfer medium stored in the expansion compensation module 1 is replenished to the suction side of the circulation pump 3 through the third pipeline 53 under the action of the system pressure difference, thereby maintaining the flow and pressure stability of the circulation module and avoiding medium interruption or liquid shortage on the load 8 side.

[0033] The addition / discharge module 9 of the present invention is connected to the pipeline between the load 8 and the one-way valve 4.

[0034] In application, the filling and draining module 9 of the present invention includes: a dual-purpose filling and draining tank 93, a ninth pipeline 59, and a power switching device. In practical application, the filling and draining module 9 of the present invention also includes: a maintenance manual valve 921.

[0035] In this invention, the maintenance hand valve 921 is connected in parallel with the check valve 4 to ensure that the check valve 4 can be bypassed during drainage, thus achieving complete recovery of the heat transfer medium. Specifically, the maintenance hand valve 921 is installed on both sides of the check valve 4 via a three-way valve, forming a bypass path during drainage to ensure that the heat transfer medium in the pipelines and components behind the check valve 4 (such as the circulating pump 3 and the fourth pipeline 54) can be completely recovered, avoiding heat transfer medium residue.

[0036] Furthermore, the ninth pipeline 59 of the present invention is provided with a liquid filling and draining manual valve 922. The first end of the ninth pipeline 59 is connected to the liquid filling and draining dual-purpose tank 93 and extends into the bottom of the liquid filling and draining dual-purpose tank 93; the second end of the ninth pipeline 59 is connected to the pipeline between the load 8 and the one-way valve 4. Preferably, the second end of the ninth pipeline 59 is connected upstream of the seventh pipeline 57.

[0037] Furthermore, the middle section of the ninth pipeline 59 is a flexible hose, while the two end sections are rigid pipes. The first end of the flexible hose is connected to the rigid pipe connecting the liquid filling and draining tank 93 via the first mounting interface 591, and the second end of the flexible hose is connected to the rigid pipe connecting the seventh pipeline 57 via the second mounting interface 592. Simultaneously, a liquid filling and draining manual valve 922 is installed on the rigid pipe connecting the seventh pipeline 57. When liquid pumping or filling is not required, the liquid filling and draining manual valve 922 can be closed, and the flexible hose can be removed via the first mounting interface 591 and the second mounting interface 592, facilitating the removal of the liquid filling and draining tank 93 and the power switching device, or their reuse in other process flows.

[0038] Furthermore, the power switching device of the present invention is configured to selectively apply positive or negative pressure to the dual-purpose filling and draining tank 93. When positive pressure is applied, the dual-purpose filling and draining tank 93 is configured to fill the circulation module with heat-conducting medium; when negative pressure is applied, the dual-purpose filling and draining tank 93 is configured to recover the heat-conducting medium in the circulation module.

[0039] Furthermore, the power switching device includes a vacuum generator 91. The charging end 911 of the vacuum generator 91 is connected to a compressed air source (using compressed air as a power source eliminates the risk of electrical sparks compared to an electric pump, making it suitable for explosion-proof or clean industrial environments); the exhaust end 912 of the vacuum generator 91 is connected to the atmospheric environment; and the vacuum generating end 913 of the vacuum generator 91 is connected to the top of the dual-purpose filling and draining tank 93.

[0040] When it is necessary to apply positive pressure to the dual-purpose tank 93 for adding and draining liquid, close the exhaust valve of the exhaust end 912 of the vacuum generator 91, open the charging valve of the charging end 911 of the vacuum generator 91, and open the vacuum valve of the vacuum generating end 913, so as to use the compressed air filled in the dual-purpose tank 93 to push the heat transfer medium into the circulation module and the expansion compensation module 1 until the liquid level in the expansion compensation module 1 reaches the preset liquid level.

[0041] It is worth noting that during the filling process, the fill / drain valve 922 is opened and the maintenance valve 921 is closed. The flow path of the heat transfer medium is as follows: fill / drain dual-purpose tank 93, ninth pipeline 59, seventh pipeline 57, evaporator 7, eighth pipeline 58, load 8, second pipeline 52, and expansion compensation module 1. When the liquid level in expansion compensation module 1 reaches the preset level, the fill / drain valve 922 is closed, the circulation pump 3 is turned on, the heat transfer medium in expansion compensation module 1 flows out, and sequentially fills the third pipeline 53, circulation pump 3, fourth shut-off line, and check valve 4, thus initiating the circulation process of the circulation module.

[0042] When it is necessary to apply negative pressure to the dual-purpose tank 93 for adding and draining liquid, open the exhaust valve of the exhaust end 912 of the vacuum generator 91, close the charging valve of the charging end 911 of the vacuum generator 91, and open the vacuum valve of the vacuum generating end 913, so as to use negative pressure to draw the heat transfer medium in the circulation module and the expansion compensation module 1 into the dual-purpose tank 93 for adding and draining liquid until there is no heat transfer medium in the recovery flow path to continue to flow back to the dual-purpose tank 93 for adding and draining liquid.

[0043] It is worth noting that during the drainage process, opening the fill / drain manual valve 922 and the maintenance manual valve 921 results in two flow paths for the heat transfer medium: Path 1, Path 2, Path 1: Expansion compensation module 1, second pipeline 52, load 8, eighth pipeline 58, evaporator 7, seventh pipeline 57, ninth pipeline 59, and fill / drain dual-purpose tank 93. Path 2: Expansion compensation module 1, third pipeline 53, circulating pump 3, fourth pipeline 54, maintenance manual valve 921, ninth pipeline 59, and fill / drain dual-purpose tank 93.

[0044] In summary, the dual-purpose filling and draining tank 93 of this invention integrates storage, filling, and recovery functions, saving space and equipment costs. The filling and draining module 9 can realize filling and draining by switching pressure states (positive pressure / negative pressure). Positive pressure filling avoids air mixing; negative pressure recovery utilizes pressure difference traction for more thorough draining. In addition, the ninth pipeline 59 is connected between the load 8 and the one-way valve 4, ensuring that the medium can preferentially fill the external load 8 circuit during filling, and that the heat transfer medium can be recovered by opening the maintenance hand valve 921 to bypass the one-way valve 4 during draining, thus solving the problem of incomplete draining.

[0045] In addition, the dual-purpose tank 93 for adding and discharging liquid of the present invention is provided with at least a feeding valve, a discharging valve and a pressure relief valve 931.

[0046] The replenishment valve is located at the top of the dual-purpose filling and draining tank 93 and is used to connect to an external heat transfer medium source. When the heat transfer medium in the tank is insufficient due to filling, new heat transfer medium can be directly replenished into the tank through the replenishment valve to avoid supply interruption.

[0047] The discharge valve is located at the lowest point of the bottom of the dual-purpose filling and draining tank 93 and is used to connect to the medium recovery device. When the tank is almost full due to the recovery of heat transfer medium, opening the discharge valve can promptly discharge the heat transfer medium into the medium recovery device, avoiding the need to pause the draining process. Simultaneously, after the draining operation is completed, or when it is necessary to completely empty or replace the heat transfer medium in the tank, opening the discharge valve can completely drain the accumulated heat transfer medium from the tank.

[0048] The pressure relief valve 931 is located at the top of the filling and draining tank 93. When the system pressure rises abnormally, the pressure relief valve 931 is opened to bring the system to a slightly positive or slightly negative pressure state. At the same time, after filling is completed, the pressure relief valve 931 is opened to release the residual compressed air in the tank into the atmosphere, allowing the pressure in the tank to return to normal.

[0049] The expansion compensation module 1 of the present invention is connected to the suction side pipeline of the circulating pump 3, and the expansion compensation module 1 stores a portion of the heat-conducting medium to compensate for the volume fluctuation of the heat-conducting medium in the circulating module.

[0050] In application, the expansion compensation module 1 is connected to the first end of the second pipe 52, and the first end of the second pipe 52 extends into the bottom of the expansion compensation module 1; the lowest point of the bottom of the expansion compensation module 1 is connected to the first end of the third pipe 53.

[0051] Furthermore, to ensure the reliability of the expansion compensation module 1's volume configuration, the volume of the expansion compensation module 1 in this invention is configured to be greater than the sum of the system's stagnant volume, the system's thermal expansion compensation volume, and the system's dynamic buffer volume. This ensures that the refrigeration system has sufficient compensation capacity under various operating conditions, such as initial charging of the heat transfer medium, thermal expansion and contraction during operation, and instantaneous flow fluctuations, avoiding pressure fluctuations, cavitation, or compensation overflow caused by insufficient compensation. Simultaneously, by reasonably limiting the volume of the expansion compensation module 1, this invention avoids cost waste due to an excessively large volume or performance bottlenecks in the refrigeration system due to an excessively small volume, thus achieving a balance between system performance and cost.

[0052] The system retention volume refers to the volume of heat transfer medium that needs to be injected into the pipelines and components in the circulation module that are not filled with heat transfer medium after the initial filling is completed. The system retention volume of this invention is configured to include at least the amount of heat transfer medium charged in the pipelines (e.g., the third pipeline 53 and the fourth pipeline 54) from the suction side of the circulation pump 3 to the outlet of the one-way valve 4, and the amount of heat transfer medium charged in the components (e.g., the sum of the volumes of the circulation pump 3 chamber and the one-way valve 4 chamber). Specifically, the system retention volume includes: In the formula, For system retention volume; The volume of the third pipeline; This refers to the volume of the fourth pipeline; This refers to the volume of the circulating pump chamber. This refers to the volume of the one-way valve cavity.

[0053] Furthermore, the system's dynamic buffer volume is a reserved safety volume used to cope with instantaneous flow fluctuations and pressure pulsations in the circulation module. The system's dynamic buffer volume of this invention is configured as the product of the volumetric flow rate in the circulation pipeline 5 under rated operating conditions and a preset buffer time. The preset buffer time can be determined based on the stability requirements and control response speed requirements of the refrigeration system.

[0054] Specifically, the system's dynamic buffer volume includes: In the formula, This is the system's dynamic buffer volume; This is the preset buffer time; This represents the volumetric flow rate of the circulating pipeline under rated operating conditions.

[0055] Furthermore, the system thermal expansion compensation volume is the volume fluctuation of the heat-conducting medium in the circulation module due to thermal expansion and contraction within the operating temperature range. That is, the net volume expansion of the heat-conducting medium in the entire circulation module during the process of the refrigeration system going from a shutdown state to a full-load operating state. However, as the main heat exchange component of the refrigeration system, the load 8 experiences the most significant temperature changes within its internal medium, making it the core source of volume fluctuation. Therefore, the system thermal expansion compensation volume of this invention is primarily configured to account for the volume fluctuation of the heat-conducting medium within the load 8. Specifically, the system thermal expansion compensation volume of this invention is primarily configured to account for the volume expansion of the heat-conducting medium within the load 8 as it rises from its lowest operating temperature to its highest operating temperature.

[0056] Specifically, the thermal expansion compensation volume of the system of the present invention includes: In the formula, This is the volume for compensating for the system's thermal expansion. The volume of the heat-conducting medium contained within the load; is the coefficient of thermal expansion of the heat-conducting medium, with units of 1 / ℃; The temperature difference of the heat transfer medium within the load as it rises from the lowest operating temperature to the highest operating temperature, expressed in °C. This is a safety margin used to provide a safety margin for the cyclic module to cope with load power fluctuations.

[0057] Furthermore, the safety factor This can be determined based on the severity of power fluctuations in load 8. Preferably, The value is 0.1 to 0.2: If the load power is stable, then... The value is 0.1; if the power of the load 8 fluctuates, then... The value is 0.15; if the power of the load fluctuates drastically, then... It is 0.2.

[0058] In practical applications, in order to make more rational use of space, the expansion compensation module 1 of the present invention includes a circulation tank 11, an expansion level tank 12, and a first pipeline 51.

[0059] The first end of the first pipe 51 is connected to the expansion tank 12 and extends into the bottom of the expansion tank 12; the second end of the first pipe 51 is connected to the top of the circulation tank 11. The expansion tank 12 stores a portion of the heat-conducting medium; a breather valve 121 is provided at the top of the expansion tank 12, and the breather valve 121 is connected to the atmosphere. The circulation tank 11 stores the heat-conducting medium; the circulation tank 11 is connected to the second pipe 52, and the first end of the second pipe 52 extends into the bottom of the circulation tank 11.

[0060] During the filling process, the heat transfer medium first enters the circulation tank 11 through the second pipeline 52. After the circulation tank 11 is filled, it then enters the expansion tank 12 through the first pipeline 51. During the draining process, the heat transfer medium in the expansion tank 12 enters the circulation tank 11 through the first pipeline 51, and the heat transfer medium in the circulation tank 11 is discharged through the second pipeline 52 and the third pipeline 53.

[0061] In practical implementation, to make the refrigeration system more compact and efficient, the volumes of the circulation tank 11 and the expansion tank 12 can be configured according to their different functions. Specifically, the volume of the circulation tank 11 is configured to be greater than the sum of the system's stagnant volume and the system's dynamic buffer volume. The volume of the expansion tank 12 is configured to be greater than or equal to the system's thermal expansion compensation volume. In some embodiments, the volume of the expansion tank 12 is configured to be 2 to 3 times the system's thermal expansion compensation volume. Preferably, the volume of the expansion tank 12 is configured to be 2.5 to 3 times the system's thermal expansion compensation volume, and the expansion tank 12 is generally filled with only half its volume of heat-conducting medium, so that the expansion tank 12 can actively absorb the expanding heat-conducting medium and replenish the contracting heat-conducting medium, converting drastic pressure changes into gradual rises and falls in its own liquid level, thereby maintaining the stability of the pressure within the circulation module.

[0062] In some embodiments, the volume of the circulation tank 11 is configured to be larger than the volume of the expansion tank 12. The large-capacity circulation tank 11 is used to meet the system's stagnation volume and dynamic buffer volume, ensuring a sufficient and stable supply of heat transfer medium on the suction side of the circulation pump 3 and preventing cavitation. In some preferred embodiments, the volume of the circulation tank 11 is configured to be twice the volume of the expansion tank 12.

[0063] It is worth noting that during the design phase of the refrigeration system, engineers can deduce and match the optimal circulating tank 11 and expansion tank 12 based on the key parameters of the target load 8, including the volume of the heat-conducting medium within the load 8, the temperature control range required by the process, and the physicochemical properties of the selected heat-conducting medium (e.g., specific heat capacity, viscosity, coefficient of expansion, etc., preferably the coefficient of expansion). This invention is applicable to various scenarios, from small laboratory testing equipment to large industrial lasers and injection molding machines. It can effectively avoid the cost waste or performance bottlenecks caused by improper tank volume estimation in traditional solutions, thereby achieving a balance between energy efficiency and operating costs in the refrigeration system.

[0064] Furthermore, during the renovation of existing facilities or the evaluation of used refrigeration systems, engineers can quickly determine whether the current refrigeration system is suitable for the new or changed load 8 by checking the volumes of the circulation tank 11 and expansion tank 12 in the refrigeration system. For example, when the refrigeration system configuration (i.e., the tank volume is determined) is known, by combining the properties of the heat transfer medium and parameters such as the volumetric flow rate in the refrigeration system, the maximum load 8 capacity and feasible temperature control range that the current refrigeration system can support can be accurately calculated, thereby clarifying its applicable scope and providing reliable data for equipment reuse and capacity upgrades.

[0065] Example 2: This embodiment of the invention discloses a method for adding and draining liquid using the refrigeration system described in Example 1.

[0066] refer to Figure 3 The method for adding and draining liquid according to the present invention includes steps SS11 to SS12, and steps SS21 to SS22.

[0067] (1) When liquid needs to be added.

[0068] Step SS11: Turn off the venting function of the venting module 9 to apply positive pressure to the venting and draining liquid dual-purpose tank 93 of the venting module 9.

[0069] During application, the refrigeration system is under a slight positive pressure. In practical applications, the dual-purpose filling and draining tank 93 has a transparent area for displaying the material level.

[0070] Step SS12: Under positive pressure, the heat transfer medium in the dual-purpose tank 93 for adding and draining liquid is pressed into the circulation module and the expansion compensation module 1 until the liquid level in the expansion compensation module 1 reaches the first preset position.

[0071] In application, the first preset position is determined based on the volume of the expansion level tank 12 in the compensation module and the volume fluctuation of the heat-conducting medium in the circulation pipeline 5. Furthermore, the expansion level tank 12 has a transparent area for displaying the material level.

[0072] Specifically, the first preset position includes: The first preset position has a value range of 1. In the formula, ; The volume of the expansion tank; This is the volume for compensating for the system's thermal expansion. Let be the cross-sectional area of ​​the expansion tank, which is equal at all points.

[0073] when for At this time, setting the initial liquid level of the expansion tank 12 to a lower position ensures the refrigeration system's ability to cope with the volume expansion of the heat transfer medium. The upper part of the expansion tank 12 has a maximum reserved space ( It is used to absorb the expanding heat-conducting medium, so that when the load power increases sharply or the temperature changes suddenly, it can most effectively buffer the pressure rise and prevent the refrigeration system from overpressure.

[0074] when for At this time, setting the initial liquid level of the expansion tank 12 to a higher position ensures the refrigeration system's ability to cope with the volume contraction of the heat transfer medium. The lower part of the expansion tank 12 stores sufficient spare heat transfer medium. This ensures that when the load power drops sharply or the refrigeration system cools down, there is sufficient heat transfer medium to replenish the circulation module in a timely manner, effectively preventing pump cavitation and cavitation phenomena.

[0075] when for and median value When the initial liquid level of the expansion tank 12 is set at the middle position of the tank body, it can simultaneously accommodate the expansion and contraction requirements. The upper and lower parts of the expansion tank 12 have symmetrical buffer volumes, providing balanced compensation for bidirectional volume fluctuations, which is suitable for complex and variable load conditions. In some preferred embodiments, the initial liquid level of the expansion tank 12 is set at the middle position of the tank body. In practical applications, when executing step SS12, before the liquid level of the expansion tank 12 in the expansion compensation unit reaches the first preset level, step SS121 is also included. Step SS121: In response to the liquid level of the dual-purpose filling and draining tank 93 being less than or equal to the second preset level, heat transfer medium is added to the dual-purpose filling and draining tank 93.

[0076] In actual implementation, the second preset position is determined based on the volume of the liquid addition and drainage tank 93, the flow rate of the heat transfer medium during liquid addition, and the horizontal height of the first end of the ninth pipeline 59 extending into the liquid addition and drainage tank 93.

[0077] Specifically, the second preset position includes: In the formula, This is the second preset position; The horizontal height at which the first end of the ninth pipeline extends into the dual-purpose tank for adding and discharging liquids; The cross-sectional area of ​​the dual-purpose filling and draining tank is equal at all points. This refers to the volumetric flow rate of the heat transfer medium flowing into the dual-purpose tank for adding and draining liquid during the liquid addition process. The first preset safety response time is the maximum time required from the issuance of the replenishment signal to the effective replenishment of the heat transfer medium into the dual-purpose filling and draining tank. As the second coefficient, .

[0078] It is worth noting that at the minimum safe liquid level Above this level, a first additional safety liquid level needs to be reserved. This first additional safety liquid level should be greater than the refrigeration system's capacity. The liquid level drop in the dual-purpose tank 93, which is used for both filling and draining liquids, is caused by the continuous consumption of heat transfer medium during the liquid filling process. Introducing a second coefficient To reserve more than Buffer medium with twice the theoretical descent height This enables the refrigeration system to cope with unexpected situations such as instantaneous fluctuations in liquid flow rate, occasional delays in feeding response time, or slight lags in sensor signals.

[0079] (2) When drainage is required.

[0080] Step SS21: Activate the venting function of the venting module 9 to apply negative pressure to the venting and draining liquid dual-purpose tank 93 of the venting module 9.

[0081] When in use, the refrigeration system is under slight negative pressure.

[0082] In practical applications, before activating the exhaust function of the exhaust module 9, step SS20 is also included. Step SS20: Open the maintenance hand valve 921.

[0083] Step SS22: Under negative pressure suction, the heat transfer medium in the circulation module and expansion compensation module 1 is recovered to the dual-purpose liquid filling and draining tank 93 until no heat transfer medium flows out of the recovery flow path.

[0084] In application, when the liquid level in the dual-purpose liquid filling and draining tank 93 is greater than or equal to the third preset level, the discharge valve is opened; when the liquid level in the dual-purpose liquid filling and draining tank 93 is lower than the second preset level, the discharge valve is closed. The third preset level can be determined based on the volume of the dual-purpose liquid filling and draining tank 93 and the discharge capacity of the discharge valve.

[0085] Specifically, the third preset position includes: In the formula, This is the third preset position; The volume of the dual-purpose filling and draining tank; The cross-sectional area of ​​the dual-purpose filling and draining tank is equal at all points. The volumetric flow rate of the heat transfer medium flowing out of the dual-purpose tank for adding and draining liquid during drainage; The second preset safety response time is the maximum time required from the issuance of the unloading signal to the effective discharge of the heat transfer medium from the dual-purpose tank for adding and discharging liquids. The third coefficient, .

[0086] It is worth noting that the refrigeration system in The rise in liquid level in the dual-purpose tank 93 for both filling and draining liquids is caused by the continuous recovery of the heat transfer medium during the drainage process. Introducing a third coefficient To reserve more than Buffer medium with twice the theoretical calculated rise height This enables the refrigeration system to cope with unexpected operating conditions such as a sudden increase in the discharge recovery flow rate, a momentary blockage in the unloading pipeline, or an occasional delay in valve response time. Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A refrigeration system, characterized in that, include: The circulation module includes a circulation pipeline (5), which is sequentially connected to a load (8), a circulation pump (3), and a check valve (4); the circulation pipeline (5) is filled with a heat-conducting medium for cooling the load (8); The addition module (9) is connected to the pipeline between the load (8) and the one-way valve (4); The expansion compensation module (1) is connected to the suction side pipeline of the circulating pump (3). The expansion compensation module (1) contains a portion of the heat-conducting medium to compensate for the volume fluctuation of the heat-conducting medium in the circulating module. The row addition module (9) includes: Dual-purpose tank for adding and draining liquid (93); The ninth pipeline (59) has its first end connected to the dual-purpose tank for adding and draining liquid (93) and extends into the bottom of the dual-purpose tank for adding and draining liquid (93); the second end of the ninth pipeline (59) is connected to the pipeline between the load (8) and the one-way valve (4); A power switching device configured to selectively apply positive or negative pressure to the dual-purpose filling and draining tank (93); When positive pressure is applied, the dual-purpose tank (93) for filling the circulation module and the expansion compensation module (1) with heat-conducting medium; when negative pressure is applied, the dual-purpose tank (93) for filling the circulation module and the expansion compensation module (1) with heat-conducting medium is configured to recover the heat-conducting medium in the circulation module and the expansion compensation module (1). The volume of the expansion compensation module (1) is configured to be greater than the sum of the system stagnation volume, the system thermal expansion compensation volume, and the system dynamic buffer volume; The system stagnation volume is configured to include at least the amount of heat-conducting medium charged in the piping and components from the suction side of the circulating pump (3) to the check valve (4); The thermal expansion compensation volume of the system is configured to be the volume fluctuation of the heat-conducting medium within the load (8); The system dynamic buffer volume is configured as the product of the volumetric flow rate in the circulation pipeline (5) and the preset buffer time; The expansion compensation module (1) includes: A circulation tank (11) contains a heat-conducting medium. The circulation tank (11) is connected to the second pipe (52) of the circulation pipeline (5). The first end of the second pipe (52) extends into the bottom of the circulation tank (11), and the second end of the second pipe (52) is connected to the outlet of the load (8). An expansion level tank (12) is provided with a breather valve (121) on the top of the expansion level tank (12), and the expansion level tank (12) contains a portion of heat-conducting medium. The first pipe (51) has its first end connected to the expansion tank (12) and extends into the bottom of the expansion tank (12); the second end of the first pipe (51) is connected to the top of the circulation tank (11).

2. The refrigeration system according to claim 1, characterized in that, The volume of the circulation tank (11) is configured to be greater than the sum of the system stagnation volume and the system dynamic buffer volume; The volume of the expansion tank (12) is configured to be greater than or equal to the thermal expansion compensation volume of the system.

3. The refrigeration system according to claim 1, characterized in that, The power switching device includes: A vacuum generator (91) is provided, with its charging end (911) connected to a compressed air source, its exhaust end (912) connected to the atmospheric environment, and its vacuum generating end (913) connected to the top of the liquid filling and draining tank (93).

4. The refrigeration system according to claim 1, characterized in that, The additional row module (9) also includes: Inspection hand valve (921), wherein the inspection hand valve (921) is connected in parallel with the one-way valve (4); Add a drain valve (922), which is installed on the ninth pipeline (59).

5. The refrigeration system according to claim 1, characterized in that, The dual-purpose tank for adding and discharging liquid (93) is equipped with: Feed valve, wherein the feed valve is connected to a heat transfer medium source; Discharge valve, which is connected to a medium recovery device; Pressure relief valve (931), which is connected to the atmospheric environment.

6. A method for adding and draining liquid in a refrigeration system as described in any one of claims 1 to 5, characterized in that, Includes the following steps: When liquid needs to be added: Turn off the venting function of the venting module (9) to apply positive pressure to the venting and draining liquid dual-purpose tank (93) of the venting module (9); Under positive pressure drive, the heat transfer medium in the dual-purpose tank (93) for adding and draining liquid is pressed into the circulation module and the expansion compensation module (1) until the liquid level in the expansion compensation module (1) reaches the first preset position; The first preset position is determined based on the volume of the expansion tank (12) in the compensation module and the volume fluctuation of the heat-conducting medium in the circulation pipeline (5). When drainage is required: Turn on the venting function of the venting module (9) to apply negative pressure to the venting and draining liquid dual-purpose tank (93) of the venting module (9); Under negative pressure suction, the heat transfer medium in the circulation module and expansion compensation module (1) is recovered to the dual-purpose tank for adding and draining liquid (93) until no heat transfer medium flows out of the recovery flow path.

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