Heat exchange performance test platform

Abstract

The invention discloses a heat exchange performance test platform, and relates to the technical field of testing of refrigeration equipment, the heat exchange performance test platform comprises a heating system, a supply system, a data acquisition system and a processing system, the heating system is used for heating a heat exchange medium to a preset temperature value, and the heated heat exchange medium is conveyed to a heat exchanger to be tested; the data acquisition system acquires the temperature Tin of the heat exchange medium at the outlet of the heating system, the temperature Tout of the heat exchange medium at the outlet of the heat exchanger to be tested, the flow v1 output by the supply system and the duration t of the test; the processing system is used for receiving data of the data acquisition system and outputting a numerical value representing the heat exchange capacity P of the heat exchanger to be tested, P = Q / t, Q = Q input-Q output = Q1-Q2 = v1 * t * Tin * C-v1 * t * Tout * C, and C is the specific heat capacity of a heat exchange medium. The heat change rate of the to-be-tested heat exchanger in unit time is calculated by calculating the input energy and the output energy of the to-be-tested heat exchanger, the heat exchange performance of the heat exchanger is directly measured according to the parameter, and the heat exchange performance of the heat exchanger can be rapidly and simply represented.

Description

Technical Field

[0001] The present invention relates to the technical field of testing refrigeration equipment, and in particular to a heat exchange performance testing platform for a heat exchanger. Background Art

[0002] Condensers and evaporators (hereinafter collectively referred to as heat exchangers) are important components in refrigeration equipment such as refrigerators and air conditioners. Reducing the manufacturing cost of heat exchangers can significantly reduce the manufacturing cost of products. However, there is currently a lack of means to characterize the heat transfer or heat dissipation performance of heat exchangers. The heat transfer capacity can only be measured inside the refrigeration equipment. Therefore, there is an urgent need for a test method that can quickly and easily characterize the heat transfer performance of the heat exchanger. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a heat exchange performance testing platform that can test the heat exchange performance of a heat exchanger and characterize the heat exchange capacity of the heat exchanger.

[0004] According to the first embodiment of the present invention, the heat exchange performance test platform includes a heating system, a supply system, a data acquisition system and a processing system. The heating system is used to heat the heat exchange medium to a preset temperature value, and the heated heat exchange medium is transported to the heat exchanger to be tested; the supply system is used to provide the heat exchange medium to the heating system; the data acquisition system is used to obtain the temperature T of the heat exchange medium at the outlet of the heating system. in , the temperature T of the heat exchange medium at the outlet of the heat exchanger to be tested out , the flow rate v1 output by the supply system and the test duration t; the processing system is used to receive the data from the data acquisition system and output a value representing the heat exchange capacity P of the heat exchanger to be tested, where P = Q / t, Q = Q 输入 -Q 输出 =Q1-Q2=v1*t*T in *C-v1*t*T out *C, Q is the heat transferred by the heat exchanger under test, Q 输入 Q is the heat input for testing 输出 is the heat output of the test, Q1 is the heat of the heat exchange medium heated by the heating system, Q2 is the output heat of the heat exchange medium after passing through the heat exchanger to be tested, and C is the specific heat capacity of the heat exchange medium.

[0005] The heat exchange performance testing platform according to the embodiment of the present invention has at least the following beneficial effects: by calculating the input energy and output energy of the heat exchanger to be tested, according to the energy conservation formula, the heat change rate of the heat exchanger to be tested per unit time, that is, the heat exchange heat flux of the heat exchanger, is calculated. This parameter is used to directly measure the heat exchange performance of the heat exchanger, and the heat exchange performance of the heat exchanger can be quickly and easily characterized.

[0006] According to some embodiments of the present invention, the heat exchange performance test platform further includes a pipe insulation system, which is connected to the pipe at the inlet end of the heat exchanger to be tested, and is used to keep the heated heat exchange medium at a constant temperature before flowing into the heat exchanger to be tested. The pipe insulation system includes a heating device and an insulation sleeve arranged outside the pipe, and Q 输入 =Q1+Q 保温 , Q 保温 =P 保温 *t,Q 保温 The heat input to the pipe insulation system, P 保温 is the power of the heating device.

[0007] According to some embodiments of the present invention, Q 输出 =Q2+Q 散热 , Q 散热 =k*L 管路 *π*φ 套管 *(T2-T), Q 散热 is the heat dissipated by the pipe insulation system, k is the natural heat transfer coefficient, L 管路 is the length of the insulation sleeve, φ 套管 is the outer diameter of the insulation sleeve, T2 is the outer surface temperature of the insulation sleeve, and T is the ambient temperature.

[0008] According to some embodiments of the present invention, the heating system includes a thermocouple detection device, which is used to detect the temperature of the heat exchange medium output by the heating system and the input temperature of the heat exchange medium T in Set as the integrated average value of the detection values ​​of the thermocouple detection device.

[0009] According to some embodiments of the present invention, the heating system further includes a feedback device, which is used to feed back the detection value of the thermocouple detection device and regulate the heating power of the heating system in real time.

[0010] According to some embodiments of the present invention, the heat exchange performance testing platform further includes a storage tank for storing the heat exchange medium, the outlet of the storage tank is connected to the supply system, and the inlet of the storage tank is connected to the outlet end of the heat exchanger to be tested.

[0011] According to some embodiments of the present invention, a control valve is provided at the outlet end of the heating system, and the outlet end of the control valve is connected to the inlet of the storage tank and the inlet end of the pipe insulation system. The control valve is constructed as follows: when the temperature of the heat exchange medium at the outlet end of the heating system does not reach the preset temperature value, the pipeline between the control valve and the storage tank is connected, and the pipeline between the control valve and the pipe insulation system is closed; when the temperature of the heat exchange medium at the outlet end of the heating system reaches the preset temperature value, the pipeline between the control valve and the storage tank is closed, and the pipeline between the control valve and the pipe insulation system is connected.

[0012] According to some embodiments of the present invention, the storage tank is provided with a cooling device, and the cooling device is used to cool the heat exchange medium.

[0013] According to some embodiments of the present invention, the data acquisition system can record the instantaneous heating power of the heating device, the power P of the heating device 保温 Set as the integrated average value of the instantaneous heating power.

[0014] According to some embodiments of the present invention, the supply system includes a driving pump, a pressure reducing valve and a flow meter. The driving pump is used to extract the heat exchange medium and transport it to the heating system. The pressure reducing valve is used to maintain the stability of the pipeline flow pressure. The flow meter is used to measure v1.

[0015] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0017] Figure 1 Schematic diagram of a heat exchange performance testing platform according to an embodiment of the present invention;

[0018] Figure 2 for Figure 1 A schematic diagram of a storage tank is shown.

[0019] Reference numerals:

[0020] 101. Storage tank; 102. Supply system; 103. Heating system; 104. Data acquisition system; 105. Processing system; 106. Drive pump; 107. Pressure reducing valve; 108. Flow meter; 109. Cavity heater; 110. Data acquisition unit; 111. Pipe insulation system; 112. Insulation sleeve; 113. Thermocouple detection device; 114. Control valve; 115. Heat exchanger to be tested.

[0021] 201. Tank body; 202. Sealing cover; 203. Water outlet; 204. Water inlet; 205. Drain; 206. Liquid level display tube; 207. Cooling device. DETAILED DESCRIPTION

[0022] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0023] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0024] In the description of the present invention, "several" means one or more, "many" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0025] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0026] A heat exchanger is a device used to transfer heat between two fluids. It is widely used in various fields, including energy, chemical engineering, metallurgy, and refrigeration. Depending on the application requirements, the structure, characteristics, and role of the heat exchanger in the refrigeration equipment will vary.

[0027] In refrigeration equipment (refrigerators and air conditioners, etc.), heat exchangers are usually used in the following aspects:

[0028] Condenser: In the refrigeration cycle, the heat exchanger acts as a condenser, cooling and condensing the high-pressure, high-temperature refrigerant vapor into a high-pressure liquid.

[0029] Evaporator: In the evaporator, the heat exchanger absorbs heat from the surrounding environment, causing the refrigerant to evaporate from liquid to gas, thereby achieving the cooling effect.

[0030] Intercooler: In some complex refrigeration systems, the heat exchanger can be used as an intercooler to improve the refrigeration efficiency of the system.

[0031] Heat recovery: In a heat pump system, the heat exchanger can recover waste heat and use it to preheat new air or water entering the system, improving energy efficiency.

[0032] Heat exchangers usually adopt the following structural forms:

[0033] Finned heat exchangers: Finned heat exchangers consist of numerous tightly packed fins, which increase the heat transfer area and improve heat transfer efficiency. Finned heat exchangers are typically made of highly conductive materials such as aluminum or copper, offering advantages such as compact structure, excellent heat transfer, and low cost.

[0034] A shell-and-tube heat exchanger consists of inner and outer tubes, with the refrigerant flowing through the inner tube and the cooling medium (such as water or air) flowing through the outer tube. Heat transfer between the inner and outer tubes allows heat to be exchanged between the refrigerant and the cooling medium. Shell-and-tube heat exchangers offer a simple structure, easy manufacturing, and high reliability, making them suitable for all types of refrigerators.

[0035] Plate heat exchangers: These are composed of numerous thin plates with narrow channels between them, through which the refrigerant and cooling medium flow. Heat exchange occurs through heat conduction between the plates and convection between the fluids. Plate heat exchangers offer high heat transfer efficiency, compact size, and light weight, making them suitable for small refrigerators or other applications requiring high-efficiency heat exchange.

[0036] A heat exchanger is a core component in refrigeration equipment. Its function is to transfer heat from the refrigerant to a cooling medium (such as air or water), thereby cooling the refrigerant and condensing it into a liquid. In the refrigeration cycle, the heat exchanger not only cools the refrigerant but also recovers and utilizes the cooling energy, thereby improving the energy efficiency and reliability of the entire refrigeration system.

[0037] Testing the thermal performance of heat exchangers is crucial to ensuring their effectiveness and reliability in a variety of industrial applications for several reasons:

[0038] Performance Verification: Ensures that the heat exchanger meets the expected performance standards during the design and manufacturing process.

[0039] Energy efficiency optimization: Understanding the actual performance of heat exchangers helps optimize energy use, reduce operating costs, and improve overall system energy efficiency.

[0040] Design improvement: Through performance testing, we can understand its operating effect under specific conditions, discover deficiencies in the design, and then optimize the design or adjust the operating parameters to improve the energy efficiency of the equipment, reduce energy consumption, and improve the overall performance of the heat exchanger.

[0041] Customer satisfaction: Providing rigorously tested heat exchangers enhances customer confidence, ensures product quality, and protects the manufacturer's reputation.

[0042] In short, testing the heat transfer performance of the heat exchanger is a key step to ensure its stable and efficient operation under various working conditions. It is of great significance for ensuring production safety, improving economic benefits and meeting environmental protection requirements.

[0043] In the related art, one test device selects a suitable measurement module, cooling module, drive module, heating module, and voltage stabilization module based on the parameters of the microchannel heat exchanger to be tested, and connects them through standardized interface flanges. The type of experimental working fluid (such as carbon dioxide, water, or helium) is determined, and parameters such as the flow rate, pressure, and temperature of the experimental working fluid are set. The operating conditions of the heater and cooler are set to simulate the heat load of the heat exchanger to be tested under actual working conditions. Measuring equipment such as temperature sensors, pressure sensors, and flow meters are used to monitor the temperature, pressure, and flow rate of the experimental working fluid at the inlet and outlet of the heat exchanger in real time. Based on the measured temperature and pressure data, the reference temperature and pressure of the hot-side experimental working fluid are calculated. Using these reference values, the Reynolds number (Re) and Prandtl number (Pr) of the hot-side experimental working fluid are calculated. The heat transfer coefficient (K) of the heat exchanger is calculated based on the heat exchange area, heat transfer amount, and average temperature difference. The trend of the heat transfer coefficient as a function of the Reynolds number and Prandtl number is analyzed to evaluate the performance of the heat exchanger under different flow conditions. This method aims to obtain the surface heat transfer coefficient and pressure drop of the heat exchanger. Although it can characterize the heat transfer capacity, it is not intuitive enough, and the system is relatively more complex. There is a significant pressure drop in the pipeline. Although there is a pressure stabilization module for inflation and pressure stabilization, the additional heat introduced during the pressure stabilization process cannot be counted, making the calculation results lack a certain degree of accuracy. In addition, in the process of measuring the heat exchanger, it uses the convection heat transfer of cold and hot fluids to characterize it. There are many influencing factors in the heat transfer process (such as turbulence, heat transfer medium temperature, etc.), resulting in inconsistent measurement results and inconvenient troubleshooting and verification of experimental results. The connection of all components of the system relies on flanges, and the overall connection method is bulky and not easy to disassemble and replace. The system has a wide range of applications, but different heat transfer media will also cause different heat transfer coefficients under the same working conditions, which cannot serve as an effective guide.

[0044] Refer to the following Figure 1 and Figure 2 , explaining how the heat exchange performance testing platform of an embodiment of the present invention solves the above problems.

[0045] Reference Figure 1As shown, it can be understood that the heat exchange performance testing platform of the embodiment of the present invention includes a storage tank 101, a supply system 102, a heating system 103, a data acquisition system 104 and a processing system 105. Each system adopts a modular design to simplify the platform and facilitate the replacement of various components.

[0046] Among them, the storage tank 101 is used to store the heat exchange medium, which is called refrigerant and is a key substance in the refrigeration process of the refrigeration equipment. They absorb heat in the refrigeration cycle and circulate in the system to achieve the purpose of lowering the temperature. In the refrigeration cycle, the heat exchange medium absorbs heat and evaporates in the evaporator, is then compressed in the compressor, and then releases heat and condenses in the condenser. This process is repeated, so that heat is transferred from the space to be cooled (such as the inside of the refrigerator) to the external environment. The heat exchange medium can be Freon (Freon), ammonia (NH3), hydrocarbons (such as propane (R290) and butane (R600a)), hydrofluorocarbons (HFCs) (such as R134a), natural refrigerants (such as carbon dioxide and water), etc. In this embodiment, a single-phase heat exchange medium is used, that is, there is only a single heat exchange medium, which is convenient for measuring and calculating the heat exchange amount and heat flow. Compared with multi-phase heat exchange medium, it can reduce the impact on the test structure.

[0047] The supply system 102 is used to extract the heat exchange medium from the storage tank 101 and transport it to the operation pipeline of the heat exchange performance test platform, so that the heat exchange medium continues to operate in the pipeline. Figure 1 As shown, it can be understood that the supply system 102 includes a drive pump 106, a pressure reducing valve 107 and a flow meter 108. The drive pump 106 is used to extract the heat exchange medium and transport it to the heating system 103. The drive pump 106 is a pump that uses an external energy source or device to drive the flow of internal fluid. It is usually composed of a motor, a reducer, a pump body and other parts. The main types of drive pumps 106 include centrifugal pumps, screw pumps, plunger pumps and the like. The pressure reducing valve 107 is used to maintain the stability of the pipeline flow pressure to avoid inaccurate calculations caused by pressure changes. The flow meter 108 is used to measure v1. By controlling the flow meter 108, the feed amount is accurate and can be recorded in real time to facilitate the calculation of heat input. The supply system 102 can also include a pressure gauge to observe whether the pipeline flow pressure is stable so that timely adjustments can be made.

[0048] It should be noted that in related art, a compressor is also used as part of the supply system 102 to circulate the heat exchange medium in the pipeline. However, the flow rate fluctuation and resulting pipeline pressure of the compressor are greater than those of the drive pump 106. This can significantly change the pressure and temperature of the heat exchange medium, significantly affecting the heat exchange performance test of the heat exchanger 115 under test. Compared with the compressor, the drive pump 106 has a lower flow rate and lower pressure, which helps maintain the stability of the heat exchange medium in the pipeline.

[0049] The heating system 103 is used to heat the heat exchange medium to ensure that the heat exchange medium can be heated to a preset temperature value before flowing into the inlet of the heat exchanger 115 to be tested. The preset temperature value can be any temperature between room temperature and 500°C, such as 35°C, 60°C, 75°C and 85°C, etc. When testing the performance of the heat exchanger, the heat exchange medium is heated to simulate the heat load of the heat exchanger under actual working conditions to ensure the accuracy and reliability of the test results. The heated heat exchange medium flows into the inlet end of the heat exchanger 115 to be tested. In the heat exchanger 115 to be tested, the heat exchange medium will transfer its heat to the cold fluid (such as water or air), causing the temperature of the heat exchange medium to drop, while the temperature of the cold fluid to rise, that is, the temperature of the heat exchange medium flowing out of the outlet end of the heat exchanger 115 to be tested will drop.

[0050] Reference Figure 1 As shown, it is understood that the heating system 103 includes a cavity heater 109 for heating the heat exchange medium. The cavity heater 109 can have various structures, with the following being some common heating structures: The cavity heater 109 is an electric heater (such as a resistance heater or an induction heater). Electric heaters directly heat the fluid and are suitable for small-scale laboratory testing and applications requiring precise temperature control. Alternatively, the cavity heater 109 can be a hot water circulation system that transfers heat to the fluid to be heated via a heat exchanger. A hot water circulation system is suitable for applications requiring gentle heating.

[0051] The data acquisition system 104 includes multiple temperature sensors and a data collector 110. The data collector 110 is used to collect real-time data from sensors, equipment, and systems. This data may include parameters such as temperature, pressure, flow, position, and speed. For example, a temperature sensor is set at the inlet of the heat exchanger to be tested 115 to detect the input temperature T of the heat exchange medium. in A temperature sensor is set at the outlet of the heat exchanger 115 to detect the output temperature of the heat exchange medium T out , the data collector 110 collects the medium input temperature T in real time in , medium output temperature T out , medium input temperature T in It also sets the preset temperature value for the heat exchange medium heated by the heating system 103. The data collector 110 can also collect the flow rate v1 output by the supply system 102 and the test duration t in real time. The data acquisition system 104 transmits the collected data to the processing system 105 via a wired or wireless network.

[0052] The processing system 105 can be a central control system, a computer system, or a cloud platform. The processing system 105 includes built-in data processing and configuration software, which includes functions such as experiment initiation, temperature setting, curve acquisition, and automatic calculation, achieving intelligent automation. The software also includes a heat exchange medium physical property parameter library. After selecting a heat exchange medium, the heat exchange medium physical property parameters involved in the calculation automatically change, making the device more intelligent. The processing system 105 can calculate the input energy and output energy of the heat exchanger 115 under test. Based on the energy conservation formula, it calculates the heat change rate of the heat exchanger 115 under test per unit time, that is, the heat exchange heat flux of the heat exchanger, and displays it to the user for viewing. This parameter directly measures the heat transfer performance of the heat exchanger 115 under test. Based on the measured temperature difference (ΔT) and the specific heat capacity (Cp) of the fluid, the heat transfer rate (Q) of the heat exchanger is calculated using the formula Q = m·Cp·ΔT, where m is the mass of the fluid and ΔT is the temperature difference before and after the heat exchange. Specifically, the processing system 105 outputs a value representing the heat exchange capacity P of the heat exchanger 115 to be tested, wherein P = Q / t, Q = Q 输入 -Q 输出 =Q1-Q2=v1*t*T in *C-v1*t*T out *C=v1*t*(T in -T out )*C, Q is the heat transferred by the heat exchanger 115 to be tested, Q 输入 Q is the heat input for testing 输出 is the heat output of the test, Q1 is the heat of the heat exchange medium heated by the heating system 103, Q2 is the heat output of the heat exchange medium after passing through the heat exchanger 115 to be tested, and C is the specific heat capacity of the heat exchange medium. v1*t represents the mass of the heat exchange medium passing through the heat exchanger 115 to be tested, (T in -T out ) represents the temperature difference of the heat exchange medium before and after passing through the heat exchanger 115 to be tested.

[0053] It should be noted that, in some other embodiments, the storage tank 101 may also be eliminated, and the supply system 102 obtains the heat exchange medium by connecting to an external pipeline.

[0054] Reference Figure 1As shown, it can be understood that the heat exchange performance test platform of the embodiment of the present invention also includes a pipe insulation system 111, which is located between the heat exchanger to be tested 115 and the heating system 103. The pipeline involved is the connecting pipeline from the heating system 103 to the heat exchanger to be tested 115, that is, the pipe insulation system 111 is connected to the pipeline at the inlet end of the heat exchanger to be tested 115. The pipe insulation system 111 provides additional heat to the heat exchange medium to compensate for the heat lost by components such as the connecting pipeline (after the heat exchange medium flows through the pipeline, because the temperature of the outer wall of the pipeline is relatively low, and the external environment certainly does not reach the preset temperature value, it will dissipate heat outward, so this requires insulation. Insulation reduces outward heat dissipation), thereby prompting the heated heat exchange medium to maintain a constant temperature before flowing into the heat exchanger to be tested 115. For example, the pipe insulation system 111 includes a heating device and an insulation sleeve 112 that is sleeved outside the pipe. The heating device generates heat by heating itself and transfers it to the heat exchange medium in the pipe. The heating device is a device for converting electrical energy into thermal energy and can be an electric heating pipe, electric heating film, etc. The electric heating pipe is one of the most common heating devices. Its working principle is to convert electrical energy into thermal energy, generate heat through the heating element, and increase the temperature of the heated object. The power of the heating device is P 保温 . The electric heating film is a composite of electric heating materials and insulating materials, and the object is heated by the heat generated by the electric current on the electric heating film. The insulation sleeve 112 is a component used to reduce heat loss or prevent heat transfer. It is usually made of materials with good thermal insulation properties, such as glass fiber, rock wool, polyurethane foam, calcium silicate board, etc. The main function of the insulation sleeve 112 is to maintain the temperature inside the pipeline, equipment or container, while reducing the impact of the external environment on the internal temperature, thereby reducing the impact of the external environment on the test results. At this time, the heat input by the heat exchanger 115 to be tested increases the heat Q input by the pipeline insulation system 111. 保温 , that is, measuring the heat input Q of the heat exchanger 输入 =Q1+Q 保温 , where Q 保温 =P 保温 *t.

[0055] It should be noted that the heating device and the thermal insulation sleeve 112 can also be combined to form a heating pad, and the heating pad wraps the pipeline.

[0056] The pipe insulation system 111 is used to insulate the connecting pipes between the heating system 103 and the heat exchanger 115 to be tested, thereby reducing heat loss and solving the problems of excessive heat flow calculation results and inaccurate data due to heat dissipation of the connecting pipes. It should also be noted that if there is no pipe insulation system 111, the heat exchange medium between the heating system 103 and the heat exchanger 115 to be tested will experience temperature changes, which may cause pressure changes, leading to other energy changes, energy losses, and entropy changes, making the calculation complicated. By setting up the pipe insulation system 111, the temperature of the heat exchange medium is maintained unchanged, which can avoid various complex change calculations, and the input heat of the pipe insulation system 111 is relatively simple to calculate, thereby improving the accuracy of the test results and the convenience of the test.

[0057] It is understood that the pipe insulation system 111 is provided with a temperature-controlled thermocouple, which can provide feedback on the heating temperature of the heating device, so that the heating temperature of the heating device can be controlled as needed, that is, the heating temperature of the heating device can be set according to the experimental environment. In addition, the data acquisition system 104 can also record the instantaneous heating power in real time, which can be obtained by multiplying the current and voltage. The processing system 105 can use integration to calculate the average input power of the pipe insulation system 111 and calculate Q based on the test duration t. 保温 , so that Q 保温 The value is closer to the actual situation, which improves the accuracy of the calculation results.

[0058] It is understandable that if the insulation temperature is high, it will also cause heat dissipation, and this part of the heat loss Q 散热 Calculate it and become Q 输出 Part of Q 输出 =Q2+Q 散热 The data acquisition system 104 also obtains the outer surface temperature T2 of the insulation sleeve 112 and the ambient temperature T, Q 散热 =k*L 管路 *π*φ 套管 *(T2-T), k is the natural heat transfer coefficient, L 管路 is the length of the insulation sleeve 112, φ 套管 is the outer diameter of the insulation sleeve 112. 散热 Supplement to the total output heat Q 输出， This makes the parameters in the energy conservation formula more complete and the data obtained from the test more accurate.

[0059] It is understandable that the heating system 103 uses 220V voltage for heating, which improves the heating efficiency, and the pipe insulation system 111 uses 24V voltage for heating, which saves energy and makes the heating amount more finely controllable, which helps to maintain T instability.

[0060] The heat exchange performance testing platform of the embodiment of the present invention can clearly determine the input and output of energy, without having to consider the influence of parameters such as pressure drop on the heat exchange heat flow results throughout the process, thereby improving the accuracy of the calculation results.

[0061] The area heat exchange load can be further derived based on the effective heat exchange area of ​​the heat exchanger 115 to be tested. Based on the actual load, theoretical guidance is provided for the selection of heat exchangers such as evaporators and condensers. This method can be used to select suitable heat exchangers and reduce the cost increase caused by design redundancy due to high heat exchanger load.

[0062] Reference Figure 1 As shown, it can be understood that the heating system 103 includes a thermocouple detection device 113, which is used to detect the temperature of the heat exchange medium output by the heating system 103. The data acquisition system 104 can also collect the detected temperature value of the thermocouple detection device 113 in real time, and the processing system 105 can use the integral to calculate the average temperature of the detected temperature value of the thermocouple detection device 113 as the heat exchange medium input temperature T in , that is, the heat exchange medium input temperature T in is the integral average value of the detection value of the thermocouple detection device 113, so that the heat exchange medium input temperature T in The value is closer to the actual situation, which improves the accuracy of the calculation results.

[0063] It is understood that the heating system 103 also includes a feedback device, which is used to feed back the detection value of the thermocouple detection device 113 and adjust the heating power of the heating system 103 in real time. The heating power of the cavity heater 109 is adjusted in real time according to the temperature of the heat exchange medium measured at the outlet of the heating system 103, thereby reducing the stability of the temperature of the heat exchange medium output by the heating system 103 and ensuring T in stability.

[0064] Reference Figure 1 As shown, it can be understood that the outlet end of the heating system 103 is provided with a control valve 114, and the outlet end of the control valve 114 is connected to the inlet of the storage tank 101 and the inlet end of the pipe insulation system 111. For example, the control valve 114 is a two-position three-way solenoid valve, and the inlet of the two-position three-way solenoid valve is connected to the outlet end of the heating system 103, and the two outlets of the two-position three-way solenoid valve are respectively connected to the inlet of the storage tank 101 and the inlet end of the pipe insulation system 111, thereby controlling the heat exchange medium flowing out of the heating system 103 to selectively flow into the pipe insulation system 111 and then into the heat exchanger to be tested 115, or flow back to the storage tank 101, and then be extracted by the supply system 102 and then flow into the heating system 103 to form a cycle.

[0065] Specifically, the two-position, three-way solenoid valve is configured as follows: In the early stages of the heat exchange performance test platform startup, if the heating system 103 does not heat the heat exchange medium for sufficient time and the temperature of the heat exchange medium flowing out of the outlet of the heating system 103 does not reach a preset temperature, the feedback device generates a signal to increase the heating power of the cavity heater 109. Furthermore, the two-position, three-way solenoid valve is connected to the storage tank 101 to control the return of the heat exchange medium to the storage tank 101. Furthermore, the pipeline between the two-position, three-way solenoid valve and the pipe insulation system 111 is closed to prevent the heat exchange medium from flowing out of the heat exchanger under test 115 and causing waste. When the temperature of the heat exchange medium at the outlet of the heating system 103 reaches a preset temperature, the feedback device generates a signal to switch the pipeline between the two-position, three-way solenoid valve and the storage tank 101, closing the pipeline between the two-position, three-way solenoid valve and the pipe insulation system 111 and connecting the pipeline between the two-position, three-way solenoid valve and the pipe insulation system 111, allowing the heat exchange medium to flow through the pipe insulation system 111 to the heat exchanger under test 115. The test begins, and the test timer begins. Furthermore, the cavity heater 109 operates normally, ensuring that the temperature of the heat exchange medium is at a preset temperature value when it flows out from the outlet end of the heating system 103 .

[0066] Reference Figure 2 As shown, it can be understood that the storage tank 101 includes a tank body 201 and a sealing cover 202. The tank body 201 is provided with a water outlet 203, a water inlet 204, and a water drain 205. The water outlet 203 is connected to the inlet of the supply system 102 for supplying heat exchange medium. The water inlet 204 is connected to the outlet of the heating system 103 and the heat exchanger under test 115 for recovering the heat exchange medium. The water drain 205 is used to discharge the heat exchange medium inside the tank body 201, allowing the interior of the tank body 201 to be cleaned or replaced.

[0067] Reference Figure 2 As shown, it can be understood that the storage tank 101 is provided with a cooling device 207, which is used to cool the heat exchange medium, maintain the temperature of the heat exchange medium in the storage tank 101 stable, reduce factors that are unfavorable to the test results, and thus improve the accuracy of the calculation results.

[0068] Reference Figure 2 As shown, it is understandable that the storage tank 101 further includes a liquid level display tube 206, which can constantly observe the liquid level of the heat exchange medium inside the storage tank 101, thereby facilitating timely replenishment of the heat exchange medium.

[0069] It is understandable that all the interfaces of the storage tank 101 are external threaded 1 / 2 interfaces, and are connected to the external pipeline through a 1 / 2 ball valve switch. The 1 / 2 ball valve switch is connected to the external pipeline through a ferrule joint. The heat exchanger 115 to be tested and the supporting pipelines are connected to the heating system 103 and other structures using ferrules for easy disassembly. Compared with the related art, all the components of the system rely on flange connections, and the overall connection structure is bulky and difficult to disassemble and replace. All the interfaces of the storage tank 101 are unified as external threaded 1 / 2 interfaces, so that all the connecting pipes of the entire heat exchange performance test platform can use connecting pipes of uniform diameter, simulating the actual use of the heat exchanger for connection testing. The entire heat exchange performance test platform adopts modular testing, which is convenient for disassembly, replacement and maintenance. For example, all connecting pipes uniformly use 6mm copper pipes to ensure the consistency of the test process and the accuracy of the results. All joints are made of stainless steel.

[0070] It should be noted that all interfaces of the storage tank 101 may also be external thread interfaces of other uniform sizes, which is beneficial for unifying the diameters of all connecting pipes of the heat exchange performance test platform.

[0071] In one specific embodiment, after the heat exchange performance test platform is established, heat exchange medium is added to the storage tank, and the cooling device 207 is turned on, set to 30°C to ensure the heat exchange medium is cooled. The heating system 103 is turned on, and the temperature is set to 80°C, taking the preset temperature as 80°C as an example. At the same time, the supply system 102 is turned on, the flow meter 108 is set to an appropriate flow rate, and the pressure reducing valve 107 is adjusted to ensure a stable flow rate. The heat exchange medium is heated after passing through the heating system 103. The thermocouple detection device 113 determines whether the heat exchange medium temperature has reached the preset temperature value. The heating system 103 is still in a heating state in the early stage, and the heat exchange medium temperature at the outlet does not meet the set requirement. The two-position three-way solenoid valve controls the heat exchange medium to flow back to the storage tank. The heating system 103 uses the feedback of the heat exchange medium temperature at the outlet to determine whether to change the channel of the two-position three-way solenoid valve. If the heat exchange medium temperature at the outlet is detected to remain at the preset temperature for two consecutive minutes, the two-position three-way solenoid valve is controlled to change the channel, allowing the heat exchange medium to enter the pipeline insulation system 111. When the heating system 103 is turned on, the pipe insulation system 111 is also turned on, and the set temperature is the same as that of the heating system 103, which is used to ensure that the heat exchange medium maintains a constant temperature in the pipe between the heating system 103 and the heat exchanger to be tested 115, and to avoid inaccurate calculation results due to heat loss. At the same time, the data acquisition system 104 automatically counts the time from the time the two-position three-way solenoid valve is connected to the pipe insulation system 111, and starts counting valid data after five minutes for subsequent calculations. The data acquisition system 104 collects data at a frequency of 0.5s each time, and transmits the data records to the processing system 105 to realize automatic data collection, statistics and processing, and automatically calculate the heat exchange capacity of the heat exchanger under the working conditions. It is used to compare the heat exchange capacity of different heat exchangers or the same type of heat exchangers under different working conditions, provide data guidance for the application of heat exchangers, and improve the automation and intelligence of the system.

[0072] It should be noted that the heat exchange performance test platform can be modified according to the actual situation of the heat exchanger. Taking the condenser as an example, by manufacturing prototypes to fix parts such as fans and the heat exchanger at a certain distance or angle, it can be closer to the actual usage of heat exchangers such as condensers.

[0073] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the scope of the present invention.

Claims

1. Heat exchange performance testing platform, characterized by: include: A heating system is used to heat the heat exchange medium to a preset temperature value, and the heated heat exchange medium is transported to the heat exchanger to be tested; a supply system, configured to provide the heat exchange medium to the heating system; Data acquisition system, used to obtain the temperature T of the heat exchange medium at the outlet of the heating system in , the temperature T of the heat exchange medium at the outlet of the heat exchanger to be tested out , the flow rate v1 output by the supply system and the duration t of the test; A processing system is used to receive data from the data acquisition system and output a value representing the heat transfer capacity P of the heat exchanger to be tested, wherein P = Q / t, Q = Q 输入 -Q 输出 =Q1-Q2=v1*t*T in *C-v1*t*T out *C, Q is the heat transferred by the heat exchanger under test, Q 输入 Q is the heat input for testing 输出 is the heat output of the test, Q1 is the heat of the heat exchange medium heated by the heating system, Q2 is the output heat of the heat exchange medium after passing through the heat exchanger to be tested, and C is the specific heat capacity of the heat exchange medium.

2. The heat exchange performance testing platform according to claim 1, characterized in that: The heat exchange performance test platform also includes a pipeline insulation system, which is connected to the pipeline at the inlet end of the heat exchanger to be tested, and is used to keep the heated heat exchange medium at a constant temperature before flowing into the heat exchanger to be tested. The pipeline insulation system includes a heating device and an insulation sleeve arranged outside the pipeline, and Q 输入 =Q1+Q 保温 , Q 保温 =P 保温 *t,Q 保温 The heat input to the pipe insulation system, P 保温 is the power of the heating device.

3. The heat exchange performance testing platform according to claim 2, characterized in that: Q 输出 =Q2+Q 散热 , Q 散热 =k*L 管路 *π*φ 套管 *(T2-T), Q 散热 is the heat dissipated by the pipe insulation system, k is the natural heat transfer coefficient, L 管路 is the length of the insulation sleeve, φ 套管 is the outer diameter of the insulation sleeve, T2 is the outer surface temperature of the insulation sleeve, and T is the ambient temperature.

4. The heat exchange performance testing platform according to claim 3, characterized in that: The heating system includes a thermocouple detection device, which is used to detect the temperature of the heat exchange medium output by the heating system and the input temperature of the heat exchange medium T in Set as the integrated average value of the detection values ​​of the thermocouple detection device.

5. The heat exchange performance testing platform according to claim 4, characterized in that: The heating system further comprises a feedback device, which is used to feed back the detection value of the thermocouple detection device and regulate the heating power of the heating system in real time.

6. The heat exchange performance testing platform according to claim 5, characterized in that: The heat exchange performance testing platform further includes a storage tank for storing the heat exchange medium, the outlet of the storage tank is connected to the supply system, and the inlet of the storage tank is connected to the outlet end of the heat exchanger to be tested.

7. The heat exchange performance testing platform according to claim 6, characterized in that: A control valve is provided at the outlet end of the heating system, and the outlet end of the control valve is connected to the inlet of the storage tank and the inlet end of the pipeline insulation system. The control valve is constructed as follows: when the temperature of the heat exchange medium at the outlet end of the heating system does not reach the preset temperature value, the pipeline between the control valve and the storage tank is connected, and the pipeline between the control valve and the pipeline insulation system is closed; when the temperature of the heat exchange medium at the outlet end of the heating system reaches the preset temperature value, the pipeline between the control valve and the storage tank is closed, and the pipeline between the control valve and the pipeline insulation system is connected.

8. The heat exchange performance testing platform according to claim 6, characterized in that: The storage tank is provided with a cooling device, and the cooling device is used to cool the heat exchange medium.

9. The heat exchange performance testing platform according to claim 2, characterized in that: The data acquisition system can record the instantaneous heating power of the heating device, the power P of the heating device 保温 Set as the integrated average value of the instantaneous heating power.

10. The heat exchange performance testing platform according to claim 1, characterized in that: The supply system includes a driving pump, a pressure reducing valve and a flow meter. The driving pump is used to extract the heat exchange medium and deliver it to the heating system. The pressure reducing valve is used to maintain the pipeline flow pressure stable. The flow meter is used to measure v1.

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