A performance test system and test method for a two-phase heat exchanger

Abstract

The present invention relates to the technical field of heat exchange performance testing, and discloses a performance testing system and a testing method for a two-phase heat exchanger, wherein the performance testing system comprises a condenser evaporator, a first working fluid condenser and a second working fluid evaporator, wherein the first working fluid condenser and the second working fluid evaporator are respectively connected to the condenser evaporator, the first working fluid condenser is located above the condenser evaporator, a first working fluid buffer tank is provided between the first working fluid condenser and the condenser evaporator, the condenser evaporator is located above the second working fluid evaporator, a second working fluid buffer tank is provided between the condenser evaporator and the second working fluid evaporator, the first working fluid condenser is connected to a first medium regulating and supplying component, and the second working fluid evaporator is connected to a second medium regulating and supplying component. The temperature of the medium in the cold storage tank and the hot storage tank is controlled, the temperature of the first working fluid and the second working fluid is made more stable, and the heat exchange performance of the condenser evaporator is accurately tested under actual working conditions, thereby ensuring the accuracy of the test results of the condenser evaporator.

Description

Technical Field

[0001] The invention relates to the technical field of heat exchange performance testing, and in particular to a performance testing system and a testing method for a dual-phase heat exchanger. Background Art

[0002] With the introduction of the dual carbon policy, high-temperature heat pumps have become an important means of energy conservation and carbon reduction in industries such as industry, petrochemical industry, and construction. Among them, cascade heat pumps and closed heat pump distillation are more commonly used heat pump types. Among them, the top condenser evaporator and the tower kettle reboiler of the closed heat pump distillation, and the intermediate condenser evaporator of the cascade heat pump are several common two-phase heat exchangers. Different distillation tower materials, different working fluids, different heat exchange tubes and heat pump lubricants have a great influence on heat exchange. At present, manufacturers lack corresponding test methods for this type of heat exchanger and the influence of lubricants on heat exchange, and can only rely on engineering experience, which is risky and costly. When designing, manufacturers use heat exchanger simulation software, use light tubes (heat exchange tubes are not strengthened), perform theoretical calculations, and then retain a large margin for design. This method has many disadvantages. In actual applications, it is easy to have problems such as excessive or insufficient heat exchange area, high investment costs, and may even cause the entire system to fail to operate normally. Summary of the invention

[0003] In view of the existing technical problems, the present invention provides a performance testing system and a testing method for a dual-phase heat exchanger.

[0004] The technical solution of the present invention for solving the above-mentioned technical problems is as follows: A performance testing system for a two-phase heat exchanger includes a condenser evaporator, and also includes a first working fluid condenser and a second working fluid evaporator. The first working fluid condenser and the second working fluid evaporator are respectively connected to the condenser evaporator. The first working fluid condenser is located above the condenser evaporator. A first working fluid buffer tank is provided between the first working fluid condenser and the condenser evaporator. The condenser evaporator is located above the second working fluid evaporator. A second working fluid buffer tank is provided between the condenser evaporator and the second working fluid evaporator. The first working fluid condenser is connected to a first medium regulating and supplying component, and the second working fluid evaporator is connected to a second medium regulating and supplying component.

[0005] On the basis of the above technical solution, the present invention can also be improved as follows:

[0006] Preferably, the first working fluid condenser or the condenser evaporator is connected to an oil injection device, and the oil injection device is used to inject lubricating oil into the first working fluid condenser or the condenser evaporator.

[0007] Preferably, the first medium regulating and supplying component comprises a cold side low temperature storage tank, a cold side high temperature storage tank and a cold storage tank, the cold storage tank is respectively connected to the cold side low temperature storage tank and the cold side high temperature storage tank through a three-way regulating valve, the heights of the cold side low temperature storage tank and the cold side high temperature storage tank are greater than the height of the cold storage tank, the cold storage tank is connected to the first working fluid condenser through a first medium supply pipeline, a fourth circulating pump and a sensor are arranged on the first medium supply pipeline, and the first working fluid condenser is connected to the cold side high temperature storage tank.

[0008] Preferably, the cold-side cryogenic storage tank is connected to a first medium heat exchanger, the first medium heat exchanger is connected to a cold source, and the first medium heat exchanger is used to adjust the temperature of the first medium in the cold-side cryogenic storage tank.

[0009] Preferably, the cold-side high-temperature storage tank is connected to the first medium heat exchanger via a first circulation pump.

[0010] Preferably, the second medium regulating and supplying component comprises a hot-side high-temperature storage tank, a hot-side low-temperature storage tank and a hot storage tank, the hot storage tank is respectively connected to the hot-side high-temperature storage tank and the hot-side low-temperature storage tank through a three-way regulating valve 2, the heights of the hot-side high-temperature storage tank and the hot-side low-temperature storage tank are greater than the height of the hot storage tank, the hot storage tank is connected to the second working fluid evaporator through a second medium supply pipeline, a third circulating pump and a sensor are provided on the second medium supply pipeline, and the second working fluid evaporator is connected to the hot-side low-temperature storage tank.

[0011] Preferably, the hot-side high-temperature storage tank is connected to a second medium heat exchanger, the second medium heat exchanger is connected to a heat source, and the second medium heat exchanger is used to adjust the temperature of the second medium in the hot-side high-temperature storage tank.

[0012] Preferably, the hot-side low-temperature storage tank is connected to the second medium heat exchanger via a second circulation pump.

[0013] The present invention also discloses a performance testing method for a two-phase heat exchanger, which adopts the above-mentioned performance testing system and specifically comprises the following steps:

[0014] S1, evacuating the first working fluid condenser and the second working fluid evaporator, and filling the first working fluid and the second working fluid respectively;

[0015] S2, injecting softened water into the cold side low temperature storage tank, the cold side high temperature storage tank, the cold storage tank, the hot side high temperature storage tank, the hot side low temperature storage tank and the hot storage tank respectively;

[0016] S3, turning on the third circulation pump and the fourth circulation pump;

[0017] S4, setting the temperature of the first medium in the cold storage tank and the temperature difference between the inlet and outlet of the first medium in the first working medium condenser; setting the temperature of the second medium in the hot storage tank and the temperature difference between the inlet and outlet of the second medium in the second working medium evaporator;

[0018] S5, regulating the regulating valve 3, so that the first working medium in the first working medium buffer tank enters the condenser evaporator and submerges the heat exchange tube in the condenser evaporator;

[0019] S6, regulating the regulating valve 4 so that the second working fluid in the second working fluid evaporator floods the heat exchange tube in the second working fluid evaporator;

[0020] S7. Enter the operating condition and test the heat exchange performance of the condenser evaporator.

[0021] Preferably, the method further includes step S8, injecting lubricating oil into the first working medium condenser or condenser evaporator to test the heat exchange performance of the condenser evaporator.

[0022] The beneficial effects of the present invention are:

[0023] (1) The temperature of the medium in the cold storage tank and the hot storage tank is controlled by the low-temperature storage tank, the high-temperature storage tank and the three-way regulating valve. Since the first medium exchanges heat with the first working medium in the first working medium condenser, and the second medium exchanges heat with the second working medium in the second working medium evaporator, when the temperature of the first medium and the second medium is accurately controlled, the temperature of the first working medium and the second working medium can be more stable, and the flow fluctuation is small, and the cold and heat are coupled to ensure the stability of the system, and the heat exchange performance of the condenser evaporator under actual working conditions is accurately tested, thereby ensuring the accuracy of the condenser evaporator test results.

[0024] (2) There is no need to add power equipment such as pumps to supply liquid to the condenser evaporator. Relying on the gravity and siphon phenomenon of the working fluid itself, the working fluid circulates between the first working fluid condenser, the second working fluid evaporator and the condenser evaporator, thereby testing the heat exchange performance of the condenser evaporator, simplifying the system structure and reducing the test cost.

[0025] (3) The use of regulating valves and working fluid pumps can not only accurately test the heat exchange performance during single circulation, but also accurately test the multiple circulation liquid supply method, and can test the heat exchange performance of various forms of condenser evaporators.

[0026] (4) Adding a buffer tank on the working fluid side can better adjust the circulation volume of the working fluid, and can also prevent the working fluid from condensing and accumulating in the condenser evaporator and affecting its heat exchange performance, thereby ensuring the accuracy of the condenser evaporator performance test results. At the same time, the buffer tank can be used as a working fluid filling and recovery device to improve the convenience of use.

[0027] (5) By adding an oil injection device, the heat transfer performance of the condenser evaporator after the working fluid and oil are mixed can be tested, and the influence of lubricating oil on the heat transfer of the condenser evaporator can be tested to ensure the normal operation of the heat pump system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of a performance testing system for a two-phase heat exchanger of the present invention.

[0029] The accompanying drawings are marked as follows: 1. First working fluid condenser; 2. Condenser evaporator; 3. Second working fluid evaporator; 4. Oil injection device; 5. Cold side low temperature storage tank; 6. Cold side high temperature storage tank; 7. Cold storage tank; 8. Hot side high temperature storage tank; 9. Hot side low temperature storage tank; 10. Hot storage tank; 11. First medium heat exchanger; 12. First circulation pump; 13. Three-way regulating valve one; 14. Second medium heat exchanger; 15. Second circulation pump; 16. Three-way regulating valve two; 17. Regulating valve one; 18. Regulating valve two; 19. Third circulation pump; 20. Fourth circulation pump; 21. Oil replenishment valve; 22. Oil injection valve; 23. Equalizing valve; 24. Regulating valve three; 25. Working fluid pump; 26. First working fluid buffer tank; 27. Second working fluid buffer tank; 28. First heat exchange coil; 29. ​​Second heat exchange coil; 30. Regulating valve four. DETAILED DESCRIPTION

[0030] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0031] like Figure 1As shown, the present invention discloses a performance test system for a two-phase heat exchanger, including a condenser evaporator 2, and also including a first working fluid condenser 1 and a second working fluid evaporator 3, wherein the first working fluid condenser 1 and the second working fluid evaporator 3 are respectively connected to the condenser evaporator 2, the first working fluid condenser 1 is located above the condenser evaporator 2, a first working fluid buffer tank 26 is provided between the first working fluid condenser 1 and the condenser evaporator 2, and a parallel regulating valve 24 and a working fluid pump 25 are provided on the pipeline between the first working fluid buffer tank 26 and the condenser evaporator 2; the condenser evaporator 2 is located above the second working fluid condenser 1 and the second working fluid evaporator 3; Above the medium evaporator 3, a second medium buffer tank 27 is provided between the condenser evaporator 2 and the second medium evaporator 3, a regulating valve 4 30 is provided on the pipeline between the second medium buffer tank 27 and the second medium evaporator 3, the first medium condenser 1 is connected to the first medium regulating and supplying component, the first medium in the first medium condenser 1 exchanges heat with the first medium, the second medium evaporator 3 is connected to the second medium regulating and supplying component, the second medium in the second medium evaporator 3 exchanges heat with the second medium, the first medium and the second medium are coupled to exchange heat in the condenser evaporator 2, and the heat exchange performance of the condenser evaporator 2 is tested. Among them, "A" in the figure represents the cold source inlet and outlet, "B" represents the high temperature heat source inlet and outlet, and "C" and "D" both represent the cold and heat source interfaces.

[0032] Specifically, the first medium regulating and supplying component includes a cold side low temperature storage tank 5, a cold side high temperature storage tank 6 and a cold storage tank 7. The cold side low temperature storage tank 5, the cold side high temperature storage tank 6 and the cold storage tank 7 are all provided with a temperature sensor and a liquid level sensor. The cold storage tank 7 is respectively connected to the cold side low temperature storage tank 5 and the cold side high temperature storage tank 6 through a three-way regulating valve 13. A regulating valve 17 is provided on the pipeline between the cold storage tank 7 and the three-way regulating valve 13 to facilitate adjusting the flow rate of the first medium and controlling the flow of the first medium into the cold storage tank 7. The height of tank 6 is greater than the height of the cold storage tank 7, so that the first medium flows into the cold storage tank 7 under the action of gravity, reducing the number of parts. The cold storage tank 7 is connected to the first working fluid condenser 1 through a first medium supply pipeline. A fourth circulating pump 20 and a sensor are provided on the first medium supply pipeline. The fourth circulating pump 20 is used to control the flow rate of the first medium. The sensor includes a flow sensor, a pressure sensor and a temperature sensor. The first working fluid condenser 1 is connected to the cold side high temperature storage tank 6 to realize the recycling of the first medium and ensure the normal operation of the test system.

[0033] In this embodiment, the first medium is water, the fourth circulation pump 20 is a water pump, the cold storage tank 7 is a normal pressure water tank, and the water temperature in the cold storage tank 7 is higher than 5°C. The water temperature of the cold storage tank 7 is controlled by adjusting the three-way regulating valve 13, and the water temperature of the cold storage tank 7 is set according to the required cold water supply temperature. The function of the cold storage tank 7 is to ensure the stability of the cold water supply temperature, and the water supply temperature to the first working medium condenser 1 will not fluctuate due to the adjustment of the three-way regulating valve 13, and solve the problem that the three-way regulating valve 13 is used directly before the fourth circulation pump 20, which is easy to cause the valve to close suddenly or the water flow to decrease, thereby causing cavitation in the fourth circulation pump 20.

[0034] In this embodiment, the cold side low temperature storage tank 5 is connected to a first medium heat exchanger 11, and the first medium heat exchanger 11 is connected to a cold source. The cold side high temperature storage tank 6 is connected to the first medium heat exchanger 11 through a first circulating pump 12, and the first medium heat exchanger 11 is used to adjust the temperature of the first working medium in the cold side low temperature storage tank 5. The temperature of the cold source is determined according to the actual operating conditions. The cold source generally adopts an ice water unit or circulating cooling water. The temperature of the first medium in the cold side low temperature storage tank 5 is lower than the temperature of the first medium in the cold storage tank 7, and the temperature difference between the two is less than or equal to 10°C. The temperature of the first medium in the cold storage tank 7 can be more stably controlled. In this embodiment, the water supply temperature of the cold storage tank 7 can be more stably controlled to ensure the accuracy of the measurement results.

[0035] During operation, the first working fluid evaporates in the condenser evaporator 2 , and the first gas phase working fluid has a low density and will enter the first working fluid condenser 1 which is located at a higher position. The first working fluid exchanges heat with the first medium in the first working fluid condenser 1, that is, the first working fluid exchanges heat with cold water, wherein the cold water absorbs heat to form water vapor and enters the cold side high temperature storage tank 6, and the water in the cold side high temperature storage tank 6 enters the first medium heat exchanger 11 through the first circulating pump 12 for cooling, and then enters the cold side low temperature storage tank 5, and the first circulating pump 12 is used to balance the water levels of the cold side low temperature storage tank 5 and the cold side high temperature storage tank 6, so as to avoid the situation that the water level of the cold side high temperature storage tank 6 continues to rise and the water in the cold side low temperature storage tank 5 continues to decrease, to ensure the balance and temperature difference of the water levels of the two, to ensure the regulation of the water temperature in the cold storage tank 7, and to realize the recycling of water, thereby reducing the testing cost; the first working fluid is liquefied after heat exchange in the first working fluid condenser 1, and since the first working fluid buffer tank 26 is provided between the first working fluid condenser 1 and the condensation evaporator 2, the liquefied first working fluid flows into the first working fluid buffer tank 26 by gravity, and the diameter of the liquid supply pipeline ensures that the flow rate is less than 0.5m / s, ensuring half-pipe flow. The half-pipe flow allows the liquid to flow downward better and the gas phase to flow upward without causing gas blockage problems. At the same time, there is no need to set up a gas phase balance pipe.

[0036] If the first working fluid side in the condenser evaporator 2 is set to a single cycle, the regulating valve three 24 is used to control the liquid supply flow rate of the first working fluid buffer tank 26 to the condenser evaporator 2, thereby controlling the evaporation temperature of the first working fluid or the liquid level of the condenser evaporator 2. If the first working fluid side in the condenser evaporator 2 is set to multiple cycles, the working fluid pump 25 is used to adjust the flow rate of the first working fluid according to actual needs to ensure that a sufficient amount of the first working fluid enters the condenser evaporator 2. By regulating the valve three 24 and the working fluid pump 25, not only can the heat exchange performance of the condenser evaporator 2 in a single cycle be accurately tested, but also the liquid supply mode in multiple cycles can be accurately tested, so as to realize the testing of the heat exchange performance of the condenser evaporator 2 in various forms, improve the scope of application, and reduce the testing cost.

[0037] Among them, the first working fluid buffer tank 26 plays a buffering role on the first working fluid, avoiding the first working fluid from accumulating in the first working fluid condenser 1 and affecting the heat exchange effect of the first working fluid condenser 1; when the first working fluid buffer tank 26 is used for the circulation of the first working fluid, the optimal working fluid demand of the condensing evaporator 2 is controlled, and the remaining first working fluid is buffered in the first working fluid buffer tank 26; when multiple flows are supplied to the condensing evaporator 2, pump cavitation and vibration problems caused by vacuuming in front of the working fluid pump 25 are avoided, and the tank can be used for the filling and recovery of the first working fluid.

[0038] Among them, the filling method of the first working fluid includes: closing the valves at the inlet and outlet of the first working fluid buffer tank 26, a first heat exchange coil 28 is provided in the first working fluid buffer tank 26, a cold source (chilled water) circulates inside the first heat exchange coil 28, the temperature and pressure in the first working fluid buffer tank 26 are reduced, and the first working fluid is filled through the first working fluid filling port of the first working fluid buffer tank 26.

[0039] Recovery of the first working fluid: The valves at the inlet and outlet of the first working fluid buffer tank 26 are closed to allow the first working fluid to accumulate in the first working fluid buffer tank 26. The heat source (hot water) circulates inside the first heat exchange coil 28, and the temperature and pressure inside the first working fluid buffer tank 26 increase. The first working fluid is recovered through the first working fluid filling port by relying on the pressure difference, that is, the first working fluid is filled and recovered through the first working fluid filling port.

[0040] In an optional embodiment, if the temperature of the first medium in the cold storage tank 7 needs to be lower than 0°C during testing, the first medium uses a low-temperature refrigerant such as ethylene glycol to ensure that the first medium can flow normally to the first working fluid condenser 1 for normal heat exchange.

[0041] In this embodiment, specifically, the second medium regulating supply component includes a hot side high temperature storage tank 8, a hot side low temperature storage tank 9 and a hot storage tank 10. The hot storage tank 10 is connected to the hot side high temperature storage tank 8 and the hot side low temperature storage tank 9 respectively through a three-way regulating valve 16. A regulating valve 18 is provided on the pipeline between the hot storage tank 10 and the three-way regulating valve 16 to facilitate the regulation of the second medium entering the hot storage tank 10. The heights of the hot side high temperature storage tank 8 and the hot side low temperature tank 9 are greater than the height of the hot storage tank 10, so that the second medium flows to the hot storage tank 10 by gravity, and the second medium in the hot side high temperature tank 8 The temperature of the second medium in the heat storage tank 10 is greater than that of the second medium in the heat storage tank 10, and the temperature difference between the two is less than or equal to 10°C, so as to realize more stable and quick control of the temperature of the second medium in the heat storage tank 10. The heat storage tank 10 is connected to the second working medium evaporator 3 through the second medium supply pipeline. The second medium supply pipeline is provided with a third circulating pump 19 and a sensor. The third circulating pump 19 is used to control the flow rate of the second medium. The sensor includes a flow sensor, a pressure sensor and a temperature sensor. The second working medium evaporator 3 is connected to the hot side low-temperature storage tank 9 to realize the recycling of the second medium and ensure the normal circulation operation of the system.

[0042] Among them, the cold side low temperature storage tank 5, the cold side high temperature storage tank 6, the cold storage tank 7, the hot side high temperature storage tank 8, the hot side low temperature storage tank 9 and the hot storage tank 10 are all equipped with temperature sensors and liquid level sensors. Figure 1 In the figure, “TT” indicates temperature sensor, “LT” indicates level sensor, “PT” indicates pressure sensor, and “FT” indicates flow sensor.

[0043] In this embodiment, the second working medium is hot water, the heat storage tank 10 is a normal pressure water tank, the water temperature in the heat storage tank 10 is lower than 90° C. The temperature of the hot water in the heat storage tank 10 is controlled by the three-way regulating valve 16. The function of the heat storage tank 10 is to ensure the stability of the hot water supply temperature, and the water temperature supplied to the second working medium evaporator 3 will not fluctuate due to the adjustment of the three-way regulating valve 16. It also solves the problem that the three-way regulating valve 16 is used directly before the third circulating pump 19, which may easily cause the valve to close suddenly or the water flow to decrease, thereby causing cavitation in the third circulating pump 19.

[0044] Furthermore, the hot side high temperature storage tank 8 is connected to a second medium heat exchanger 14, the second medium heat exchanger 14 is connected to a heat source, the hot side low temperature storage tank 9 is connected to the second medium heat exchanger 14 through a second circulation pump 15, and the second medium heat exchanger 14 is used to adjust the temperature of the second medium in the hot side high temperature storage tank 8. The temperature of the heat source is determined according to the actual operating conditions, and the heat source generally uses high temperature hot water or steam.

[0045] During operation, the second working fluid exchanges heat with the second medium in the second working fluid evaporator 3. In this embodiment, the second medium is hot water, that is, the second working fluid exchanges heat with the hot water in the second working fluid evaporator 3. The hot water is cooled and enters the hot side low temperature storage tank 9 through the pipeline. The water in the hot side low temperature storage tank 9 enters the second medium heat exchanger 14 through the second circulating pump 15, and enters the hot side high temperature storage tank 8 after being heated by the second medium heat exchanger 14. The second circulating pump 15 is used to balance the water levels of the hot side high temperature storage tank 8 and the hot side low temperature storage tank 9, so as to avoid the water level of the hot side low temperature storage tank 9 constantly rising and the water in the hot side high temperature storage tank 8 constantly rising. The lowering ensures the balance of water levels and temperature difference between the two, thereby ensuring the regulation of water temperature in the heat storage tank 10 and realizing the recycling of water; the second working fluid exchanges heat and evaporates in the second working fluid evaporator 3, and the second gas phase working fluid has a low density and will enter the higher position condenser evaporator 2. The second working fluid exchanges heat with the first working fluid in the condenser evaporator 2, and the first working fluid evaporates. The density of the first gas phase working fluid will enter the higher height first working fluid condenser 1, and the second working fluid liquefies and enters the second working fluid buffer tank 27 by gravity. By adjusting the regulating valve four 30, the second working fluid demand of the second working fluid evaporator 3 is adjusted. Water is used as an indirect heating medium to reduce the risk of explosion caused by direct heating of flammable and explosive working fluids. A second heat exchange coil 29 is provided in the second working fluid buffer tank 27. The replenishment and recovery of the second working fluid are the same as those of the first working fluid, which will not be repeated here.

[0046] When it is necessary to test the influence of lubricating oil on the heat exchange performance of condenser evaporator 2, the first working fluid condenser 1 or condenser evaporator 2 is connected with an oil injection device 4, and the oil injection device 4 is used to inject a certain amount of lubricating oil into the first working fluid condenser 1 or condenser evaporator 2. In this embodiment, the first working fluid condenser 1 is connected with the oil injection device 4, the lubricating oil is miscible with the first working fluid, and the lubricating oil and the first working fluid are gradually circulated into the condenser evaporator 2. The oil injection device 4 is equipped with an oil replenishment valve 21, an oil injection valve 22 and a liquid level meter. When the lubricating oil is injected into the first working fluid condenser 1, the pressure equalizing valve 23 is opened first, and the oil injection valve 22 is ensured to be closed at this time. When the pressure of the oil injection device 4 and the first working fluid condenser 1 is balanced, the oil injection valve 22 is opened, and a certain volume of lubricating oil is injected into the first working fluid condenser 1 by gravity. The injection amount of lubricating oil can be observed by a liquid level sensor.

[0047] Furthermore, a pair of large viewing mirrors are added to the shell side of the condenser evaporator 2, so that the internal heat exchange state and the position and state of the lubricating oil can be clearly seen; in the immiscible state, the lubricating oil and the working medium are stratified, and in this case, the lubricating oil is generally easy to stick to the wall of the heat exchange tube; in the slightly soluble state, the lubricating oil and the working medium are stratified, and the lubricating oil basically does not stick to the heat exchange tube; in the completely miscible state, the lubricating oil and the working medium are not stratified and are completely miscible. In this way, the heat exchange performance of the condenser evaporator 2 under different states of the working medium and the lubricating oil can be tested.

[0048] The condenser evaporator 2 can be a horizontal shell and tube condenser evaporator, in which the working medium evaporates on the shell side and condenses on the tube side; or a vertical or horizontal siphon evaporator, in which the working medium condenses on the shell side and evaporates on the tube side, the vaporization rate is controlled below 30%, and the heat exchange effect is better; or a vertical falling film evaporator, in which the tube side pump forces liquid supply, the shell side working medium condenses, and the tube side working medium evaporates; or a horizontal falling film condenser evaporator, in which the shell side working medium evaporates and the tube side working medium condenses.

[0049] The present invention discloses a performance test method for a two-phase heat exchanger, using the performance test system as described above. In this embodiment, the condenser evaporator 2 at the top of a closed heat pump distillation tower of a methanol distillation tower is tested, and the condenser evaporator 2 is a horizontal shell and tube condenser evaporator;

[0050] The test conditions are as follows: the first working fluid is R245FA, the evaporation temperature is 55°C, and the shell side pool boiling; the second working fluid is the top gas of the distillation tower, 100% methanol, the condensation temperature is 65°C, and the condensation is in the tube.

[0051] The specific steps include:

[0052] S1, evacuating the first working fluid condenser 1 and the second working fluid evaporator 3, and filling the first working fluid and the second working fluid respectively;

[0053] S2, injecting softened water into the cold side low temperature storage tank 5, the cold side high temperature storage tank 6, the cold storage tank 7, the hot side high temperature storage tank 8, the hot side low temperature storage tank 9 and the hot storage tank 10 respectively;

[0054] S3, turning on the third circulation pump 19 and the fourth circulation pump 20, and controlling the flow of the circulation pumps according to the liquid level or flow;

[0055] S4. Set the temperature of the first medium in the cold storage tank 7 to 47°C. In this embodiment, the first medium is cold water. Set the temperature difference between the inlet and outlet of the first medium in the first working medium condenser 1 to 5°C, that is, the outlet water temperature is 52°C. According to the above temperature difference, the cold water flow rate is adjusted by the fourth circulating pump 20; set the temperature of the second medium in the hot storage tank 10 to 73°C. In this embodiment, the second medium is hot water, and set the temperature difference between the inlet and outlet of the second medium in the second working medium evaporator 3 to 5°C, that is, the outlet water temperature is designed to be 68°C; set the temperature of the second medium in the hot side low-temperature storage tank 9 to 42°C, set the temperature of the second medium in the hot side high-temperature storage tank 8 to 78°C, and control the cold and hot source water volumes of the first medium heat exchanger 11 and the second medium heat exchanger 14 respectively, so as to ensure that the above-mentioned first medium temperature and second medium temperature meet the set requirements.

[0056] S5, regulating the regulating valve 24, so that the first working medium in the first working medium buffer tank 26 enters the condenser evaporator 2 and submerges the heat exchange tube in the condenser evaporator 2, and the first working medium buffer tank 26 has a certain liquid level. If the amount of the first working medium in the condenser evaporator 2 is insufficient, the front and rear valves of the first working medium buffer tank 26 are closed to replenish the first working medium into the first working medium condenser 1;

[0057] S6, regulating the regulating valve 4 30, so that the second working fluid in the second working fluid evaporator 3 floods the heat exchange tube in the second working fluid evaporator 3, and the second working fluid buffer tank 27 has a certain liquid level. If the second working fluid in the second working fluid evaporator 3 is insufficient, close the inlet and outlet valves of the second working fluid buffer tank 27, and add the second working fluid into the second working fluid evaporator 3 through the second working fluid filling port;

[0058] S7, the operating condition of the condenser evaporator 2, the first working medium side, the water temperature of the cold storage tank 7 can be adjusted according to the pressure or temperature of the evaporation side. If the evaporation temperature of the first working medium deviates from 55°C, the water temperature of the cold storage tank 7 is fine-tuned: if the evaporation temperature is higher than 55°C, the water temperature of the cold storage tank 7 needs to be lowered; if the evaporation temperature is lower than 55°C, the water temperature of the cold storage tank 7 needs to be increased;

[0059] If the condensation temperature of the second working fluid deviates from 65°C, the water temperature of the heat storage tank 10 needs to be fine-tuned; if the condensation temperature is higher than 65°C, the water temperature of the heat storage tank 10 needs to be lowered; if the condensation temperature is lower than 65°C, the water temperature of the heat storage tank 10 needs to be increased.

[0060] The system gradually stabilizes and approaches the actual operating conditions, and then the heat exchange performance of the condenser evaporator 2 is tested, wherein the heat exchange performance includes heat exchange amount, heat transfer coefficient, flow rate, etc.

[0061] The present invention adjusts the heat exchange temperature of the first working fluid and the second working fluid by accurately controlling the temperature of cold water and hot water, and accurately tests the heat exchange performance of the condenser evaporator 2 under actual working conditions based on the temperature of the first working fluid and the second working fluid after heat exchange, thereby ensuring the accuracy of the test results and the normal operation of the system.

[0062] In an optional embodiment, step S8 is also included. When it is necessary to test the influence of lubricating oil on the heat exchange performance of condenser evaporator 2, lubricating oil is injected into the first working medium condenser 1 or condenser evaporator 2 to test the heat exchange performance of the condenser evaporator 2. When different types or different amounts of lubricating oil are mixed into the working medium, the corresponding heat exchange performance of condenser evaporator 2 is tested. By adding an oil injection device 4, the heat exchange performance of the working medium after mixing with oil can be tested; at the same time, the heat exchange state and lubricating oil state in condenser evaporator 2 can be visually checked by installing a large viewing mirror, which can better guide the design of condenser evaporator 2 and the oil return design of heat pump system.

[0063] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A performance test system for a two-phase heat exchanger, comprising a condenser evaporator (2), characterized in that: The invention also comprises a first working fluid condenser (1) and a second working fluid evaporator (3), wherein the first working fluid condenser (1) and the second working fluid evaporator (3) are respectively connected to the condenser evaporator (2), the first working fluid condenser (1) is located above the condenser evaporator (2), a first working fluid buffer tank (26) is provided between the first working fluid condenser (1) and the condenser evaporator (2), the condenser evaporator (2) is located above the second working fluid evaporator (3), a second working fluid buffer tank (27) is provided between the condenser evaporator (2) and the second working fluid evaporator (3), the first working fluid condenser (1) is connected to a first medium regulating and supplying component, the first working fluid in the first working fluid condenser (1) exchanges heat with the first medium, the second working fluid evaporator (3) is connected to a second medium regulating and supplying component, the second working fluid in the second working fluid evaporator (3) exchanges heat with the second medium, the first working fluid and the second working fluid are coupled to exchange heat in the condenser evaporator (2), and the heat exchange performance of the condenser evaporator (2) is tested.

2. The performance test system of the two-phase heat exchanger according to claim 1, characterized in that: The first working medium condenser (1) or the condenser evaporator (2) is connected to an oil injection device (4), and the oil injection device (4) is used to inject lubricating oil into the first working medium condenser (1) or the condenser evaporator (2).

3. The performance test system of the two-phase heat exchanger according to claim 1 or 2, characterized in that: The first medium regulating and supplying component comprises a cold side low temperature storage tank (5), a cold side high temperature storage tank (6) and a cold storage tank (7); the cold storage tank (7) is respectively connected to the cold side low temperature storage tank (5) and the cold side high temperature storage tank (6) via a three-way regulating valve (13); the heights of the cold side low temperature storage tank (5) and the cold side high temperature storage tank (6) are greater than the height of the cold storage tank (7); the cold storage tank (7) is connected to the first working medium condenser (1) via a first medium supply pipeline; a fourth circulating pump (20) and a sensor are provided on the first medium supply pipeline; and the first working medium condenser (1) is connected to the cold side high temperature storage tank (6).

4. The performance test system of the two-phase heat exchanger according to claim 3, characterized in that: The cold side low temperature storage tank (5) is connected to a first medium heat exchanger (11), the first medium heat exchanger (11) is connected to a cold source, and the first medium heat exchanger (11) is used to adjust the temperature of the first medium in the cold side low temperature storage tank (5).

5. The performance test system of the two-phase heat exchanger according to claim 4, characterized in that: The cold-side high-temperature storage tank (6) is connected to the first medium heat exchanger (11) via a first circulation pump (12).

6. The performance test system of the two-phase heat exchanger according to claim 1 or 2, characterized in that: The second medium regulating and supplying component comprises a hot side high temperature storage tank (8), a hot side low temperature storage tank (9) and a hot storage tank (10); the hot storage tank (10) is respectively connected to the hot side high temperature storage tank (8) and the hot side low temperature storage tank (9) via a second three-way regulating valve (16); the heights of the hot side high temperature storage tank (8) and the hot side low temperature storage tank (9) are greater than the height of the hot storage tank (10); the hot storage tank (10) is connected to the second working fluid evaporator (3) via a second medium supply pipeline; a third circulating pump (19) and a sensor are provided on the second medium supply pipeline; and the second working fluid evaporator (3) is connected to the hot side low temperature storage tank (9).

7. The performance test system of the two-phase heat exchanger according to claim 6, characterized in that: The hot side high temperature storage tank (8) is connected to a second medium heat exchanger (14), the second medium heat exchanger (14) is connected to a heat source, and the second medium heat exchanger (14) is used to adjust the temperature of the second medium in the hot side high temperature storage tank (8).

8. The performance test system of the two-phase heat exchanger according to claim 7, characterized in that: The hot-side low-temperature storage tank (9) is connected to the second medium heat exchanger (14) via a second circulation pump (15).

9. A performance test method for a two-phase heat exchanger, using the performance test system according to any one of claims 1 to 8, characterized in that: The specific steps include: S1, evacuating the first working fluid condenser (1) and the second working fluid evaporator (3), and respectively filling the first working fluid and the second working fluid; S2, injecting softened water into the cold side low temperature storage tank (5), the cold side high temperature storage tank (6), the cold storage tank (7), the hot side high temperature storage tank (8), the hot side low temperature storage tank (9) and the hot storage tank (10) respectively; S3, turning on the third circulation pump (19) and the fourth circulation pump (20); S4, setting the temperature of the first medium in the cold storage tank (7) and the temperature difference between the inlet and outlet of the first medium in the first working medium condenser (1); setting the temperature of the second medium in the hot storage tank (10) and the temperature difference between the inlet and outlet of the second medium in the second working medium evaporator (3); S5, regulating the regulating valve three (24) so ​​that the first working medium in the first working medium buffer tank (26) enters the condenser evaporator (2) and submerges the heat exchange tubes in the condenser evaporator (2); S6, regulating the regulating valve four (30) so that the second working fluid in the second working fluid evaporator (3) floods the heat exchange tube in the second working fluid evaporator (3); S7. Enter the operating condition and test the heat exchange performance of the condenser evaporator (2).

10. The performance testing method of the two-phase heat exchanger according to claim 9, characterized in that: The method further comprises step S8 of injecting lubricating oil into the first working medium condenser (1) or the condenser evaporator (2) to test the heat exchange performance of the condenser evaporator (2).

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