A device for characterizing condensation heat transfer performance

Abstract

The present invention discloses a condensation heat transfer performance characterization device. The device includes: a dual-boiler steam generating unit for heating a liquid working medium, including a main heating mechanism and an auxiliary heating mechanism; a condensation test unit for condensing a gaseous liquid working medium, including a condensation shell, in which a heat insulation component, a condensation test piece and a cooling circulation channel are arranged, one side of the condensation shell and the heat insulation component are surrounded to form a condensation chamber, the condensation test piece is arranged in the center of the heat insulation component, and the surface of the condensation test piece is exposed in the condensation chamber, and the condensation chamber is connected to the dual-boiler steam generating unit; a condensation pressure drop unit is used to control the steady-state flow and vacuum degree of steam inside the entire device. The miniaturized, compact and modular condensation heat transfer performance characterization device provided by the present invention can minimize heat loss, and can obtain condensation heat transfer performance and mass transfer performance under different sample pure steam and extremely low non-condensable gas conditions.

Description

Technical Field

[0001] The invention relates to the technical field of heat transfer evaluation, and in particular to a condensation heat transfer performance characterization device. Background Art

[0002] With the development of micro-nano processing technology, the design and development of new micro-nano interfaces for enhancing condensation heat transfer has received widespread attention and has become a research hotspot in recent years. However, there is still no commercial product for condensation heat transfer characterization devices. At present, most condensation heat transfer experiments reported in the literature and published patents use large, complex, multi-line experimental devices, which are not only not conducive to the precise control of non-condensable gases inside the system, but also occupy a large amount of space and cause heat loss. For example, in the disclosed condensation heat transfer devices, the "A Condensation Heat Transfer Effect Evaluation System" disclosed in the patent document with publication number CN 101963588 A is limited to the condensation heat transfer evaluation of saturated steam on the metal surface. The selection range of steam conditions and test materials is narrow, and it is difficult to meet the needs of condensation heat transfer experiments with multiple requirements; the patent document with publication number CN 103196945 is limited to the evaluation of condensation heat transfer of saturated steam on the metal surface. The "condensation heat exchange experimental device capable of coupling natural circulation with forced circulation" disclosed in the patent document of A can only carry out condensation heat exchange experiments outside the tube of a single tube and a tube bundle, and it is difficult to obtain the condensation heat transfer performance under conditions containing extremely low non-condensable gases. In addition, the equipment design is complex, and the large number of pipelines can easily lead to high heat loss. The "test system for evaluating the local condensation heat transfer performance of mixed steam" disclosed in the patent document with publication number CN104407008A has difficulty in controlling the low vacuum degree of the system, and is only aimed at steam condensation experiments containing a large amount of non-condensable gases. The adjustable range of the steam temperature zone is narrow, and it is limited to condensation heat transfer tests on horizontal tubes. The "multifunctional steam condensation heat exchange and frosting process visualization experimental device" disclosed in the patent document with publication number CN108469450A has an overly large condensation cavity and long pipelines, which cause unnecessary heat loss. By attaching the sample to the Peltier surface, the calculation error of the sample surface temperature will increase.

[0003] In view of the above problems, it is necessary to develop a new generation of condensation heat transfer performance characterization device, which should meet the following characteristics: ① Characterization of condensation heat transfer performance of vertical circular surfaces of different materials (non-pipes) under pure steam or extremely low non-condensable gas conditions; ② Miniaturized and compact design to minimize heat loss. Summary of the invention

[0004] The main purpose of the present invention is to overcome the problems existing in the prior art, such as difficulty in controlling the extremely low non-condensable gas content, narrow steam temperature control range and large heat loss, and to provide a condensation heat transfer performance characterization device.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] An embodiment of the present invention provides a condensation heat transfer performance characterization device, which includes:

[0007] A double boiler steam generating unit, which is used at least to heat the liquid working medium, comprises a main heating mechanism and an auxiliary heating mechanism;

[0008] A condensation test unit, which is at least used to condense gaseous liquid working medium, comprises a condensation shell, in which a heat insulation component, a condensation test piece and a cooling circulation channel are arranged, one side of the condensation shell and the heat insulation component are surrounded to form a condensation chamber, the condensation test piece is arranged at the center of the heat insulation component, and the surface of the condensation test piece is exposed in the condensation chamber, the condensation chamber is connected to the dual boiler steam generating unit, and the condensation unit is arranged vertically;

[0009] The condensation pressure drop unit is connected with the condensation test unit and a vacuum unit, and is used at least to control the steady-state flow of steam and the vacuum degree inside the entire device.

[0010] In some embodiments, the dual-boiler steam generating unit includes a main heating mechanism, an auxiliary heating mechanism, a first temperature control mechanism, a second temperature control mechanism and a temperature sensing mechanism. A vacuum connection component is provided between the main heating mechanism and the auxiliary heating mechanism. The main heating mechanism is connected to the first temperature control mechanism, and the auxiliary heating mechanism is connected to the second temperature control mechanism.

[0011] In some embodiments, the condensation testing unit further comprises:

[0012] A temperature sensing mechanism, which is used at least to measure the steam temperature in the condensation chamber and the temperature of the condensation test piece;

[0013] a pressure sensing mechanism, which is used at least to measure the pressure in the condensation chamber; and

[0014] The visual observation mechanism is arranged at a corresponding position of the observation window provided on the condensation shell.

[0015] In some embodiments, the condensation pressure drop unit is disposed above the condensation chamber and communicated with the condensation chamber, and the condensation pressure drop unit includes a condensation pipeline, a cooling medium and a circulation component.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1) The present invention provides a miniaturized, compact and modular condensation heat transfer performance characterization device, which can minimize heat loss, and can simultaneously meet the steady-state test conditions of pure steam and extremely low non-condensable gas content controllable, and can obtain the condensation heat transfer performance and mass transfer performance under different sample pure steam and extremely low non-condensable gas conditions;

[0018] 2) The condensation heat transfer performance testing device of the present invention is easy to operate and can accurately control the non-condensable gas content in the system through the heating module of the double boiler;

[0019] 3) The present invention can realize steady-state control of steam through the condensing pressure drop module, and control the steady-state steam flow by controlling the heating power of the main boiler and the temperature of the condensing pressure drop module;

[0020] 4) The present invention can meet the vertical plane condensation heat transfer performance test of multiple working conditions and multiple materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a condensation heat transfer performance characterization device in a typical implementation scheme of the present invention.

[0022] Figure 2 This is a test schematic diagram of a condensation heat transfer performance characterization device in a typical implementation scheme of the present invention.

[0023] Figure 3 It is a graph showing the film condensation heat transfer performance on the surface of a hydrophilic smooth copper material under 40°C steam conditions (7.38 kPa) in a typical implementation scheme of the present invention.

[0024] Explanation of the reference numerals: 1-cooling water tank, 2-cooling circulation channel, 3-cooling water tank, 4-cooling circulation machine, 5-vacuum pipe joint, 6-condensing coil, 7-vacuum pump, 8-data acquisition device, 9-auxiliary heating boiler temperature controller, 10-auxiliary heating boiler, 11-vacuum connecting valve, 12-main heating boiler, 13-main heating boiler temperature controller, 14-cooling circulation machine, 15-cooling circulation machine control valve, 16-Teflon insulation block, 17-condensation chamber, 18-quartz glass observation window, 19-temperature sensor, 20-high-speed microscope, 21-condensation test piece, 22-pressure sensor. DETAILED DESCRIPTION

[0025] In view of the deficiencies in the prior art, the inventors of this case have proposed the technical solution of the present invention after long-term research and extensive practice, wherein the device has a unique miniaturized, modular, compact design structure, which can simultaneously meet the steady-state test conditions of pure steam and extremely low non-condensable gas content with controllable content. The device mainly includes a dual-boiler steam generating unit, a condensation test unit, and a condensation pressure drop unit. The extremely low non-condensable gas content in the system can be accurately controlled or non-condensable gas can be eliminated through the connection design of the main heating boiler and the auxiliary heating boiler of the dual-boiler steam generating unit; the condensation test unit can realize the collection of condensation heat transfer data and condensation mass transfer phenomena; the condensation pressure drop unit ensures the steady-state flow of steam inside the system, reduces heat loss by directly connecting to the condensation test unit, and is designed with a vacuum connection port to facilitate the control of the overall system vacuum. The technical solution, its implementation process and principles will be further explained below.

[0026] As one aspect of the technical solution of the present invention, it involves a condensation heat transfer performance characterization device, which includes:

[0027] A double boiler steam generating unit, which is used at least to heat the liquid working medium, comprises a main heating mechanism and an auxiliary heating mechanism;

[0028] A condensation test unit, which is at least used to condense gaseous liquid working medium, comprises a condensation shell, in which a heat insulation component, a condensation test piece and a cooling circulation channel are arranged, one side of the condensation shell and the heat insulation component are surrounded to form a condensation chamber, the condensation test piece is arranged at the center of the heat insulation component, and the surface of the condensation test piece is exposed in the condensation chamber, the condensation chamber is connected to the dual boiler steam generating unit, and the condensation unit is arranged vertically;

[0029] The condensation pressure drop unit is connected with the condensation test unit and a vacuum unit, and is used at least to control the steady-state flow of steam and the vacuum degree inside the entire device.

[0030] In some embodiments, the dual-boiler steam generating unit includes a main heating mechanism, an auxiliary heating mechanism, a first temperature control mechanism, a second temperature control mechanism and a temperature sensing mechanism. A vacuum connection component is provided between the main heating mechanism and the auxiliary heating mechanism. The main heating mechanism is connected to the first temperature control mechanism, and the auxiliary heating mechanism is connected to the second temperature control mechanism.

[0031] Further, the main heating mechanism may be a main heating boiler, the auxiliary heating mechanism may be an auxiliary heating boiler, the first temperature control mechanism may be a main heating boiler temperature controller, and the second temperature control mechanism may be an auxiliary heating boiler temperature controller, but is not limited thereto.

[0032] Furthermore, the dual-boiler steam generating unit is composed of a main heating boiler, an auxiliary heating boiler, a temperature sensor, a main heating boiler temperature controller, an auxiliary heating boiler temperature controller and an intermediate vacuum connecting valve. The auxiliary heating boiler is used to pre-boil the working medium to remove non-condensable gases, and the main heating boiler connected to the condensation chamber is pre-evacuated to accurately control the non-condensable gas content, and a certain proportion of non-condensable gases can be removed or reserved according to test requirements; the main heating boiler is arranged below the condensation test unit and is directly connected through a modular standard vacuum interface to reduce heat loss during the test, facilitate steam circulation and efficient reflux of condensate.

[0033] The present invention can accurately control the content of extremely low non-condensable gas in the system or remove non-condensable gas through the connection design of the main heating boiler and the auxiliary heating boiler in the double-boiler steam generating unit.

[0034] In some embodiments, the condensation testing unit is disposed above the main heating mechanism, and can realize the collection of condensation heat transfer data and condensation mass transfer phenomena.

[0035] In some embodiments, the condensation chamber has a plurality of connection ports connected to the dual boiler steam generating unit and the condensation pressure drop unit, respectively, so as to at least make the condensation test piece surface in the vertical direction. The condensation unit is connected to the main heating mechanism through a standard vacuum interface, so that the test surface is in the vertical direction.

[0036] Furthermore, the condensation test unit is composed of a cylindrical stainless steel metal shell, a front quartz glass observation window, a middle heat-insulating Teflon support block, a condensation test piece, and a back cooling water circulation channel. A temperature sensor and a pressure sensor are configured inside the condensation test module to collect relevant data such as steam temperature, cavity pressure, and condensation test piece temperature in real time.

[0037] Furthermore, the condensation test unit has three vacuum standard interfaces for changing the connection mode with the double boiler steam generating unit and the condensation pressure drop unit so that the condensation test unit can be placed vertically.

[0038] In some embodiments, the condensing unit further comprises:

[0039] A temperature sensing mechanism, which is used at least to measure the steam temperature in the condensation chamber and the temperature of the condensation test piece;

[0040] a pressure sensing mechanism, which is used at least to measure the pressure in the condensation chamber; and

[0041] The visual observation mechanism is arranged at a corresponding position of the observation window provided on the condensation shell.

[0042] Furthermore, the cooling circulation channel is in communication with a cooling medium, and the cooling medium is in communication with a condensing shell through a cooling circulation mechanism.

[0043] Furthermore, the visual observation mechanism includes a camera assembly and a light source, and the camera assembly is at least used to observe the condensate morphology of the gaseous liquid working medium on the surface of the condensation test piece and the dynamic behavior of the droplets, and evaluate the condensation heat transfer effect in combination with the test data.

[0044] Furthermore, the camera assembly may be a high-speed microscope, but is not limited thereto.

[0045] Furthermore, the visual observation mechanism is composed of a high-speed microscope and an external light source, and is placed in front of an observation window opened in the condensation shell.

[0046] Furthermore, the condensation test unit is equipped with a large-sized visual observation window, and a high-speed microscope can be used to observe the dynamic behavior of the condensate on the surface of the condensation test piece.

[0047] Further, the condensation shell includes a stainless steel shell, but is not limited thereto.

[0048] Furthermore, the thermal insulation component includes a Teflon thermal insulation block, but is not limited thereto.

[0049] Furthermore, the hollow insulating Teflon support body inside the condensation test unit provides thermal insulation protection for the cylindrical condensation test piece, so that the temperature distribution inside the condensation test piece embedded therein conforms to one-dimensional axial steady-state heat conduction, wherein four equidistant small holes are vertically arranged on the side wall of the condensation test piece along the direction of heat flow to the axial center, and temperature data is collected in real time by embedding thermocouples to infer the surface temperature of the sample.

[0050] Furthermore, the condensation shell (for example, a stainless steel shell) and the intermediate cavity of the Teflon insulation block constitute a condensation chamber, which is clamped by the shell of the cooling chamber on the other side to form an overall sealing system; the condensation test piece is embedded in the center of the Teflon insulation block and includes a thermocouple jack; the steam in the condensation chamber is condensed on the surface of the condensation test piece, and the steam is generated by the main heating mechanism and directly enters the condensation chamber for condensation.

[0051] Furthermore, an absolute pressure transmitter and a temperature probe are installed in the condensation test unit to ensure that the steam in the condensation chamber meets the test requirements.

[0052] In some embodiments, the condensation test piece has a condensation surface and back heat dissipation fins, the condensation surface is exposed in the condensation chamber, and the back heat dissipation fins are in contact with the cooling medium in the cooling circulation channel (for example, connected to a cooling water tank).

[0053] In some embodiments, the temperature sensing mechanism includes a plurality of thermocouples, which are arranged to intersect perpendicularly with the central axis of the condensation test piece. Four thermocouples are used for real-time temperature monitoring to ensure that the actual temperature of the condensation surface can be accurately reflected.

[0054] Furthermore, the liquid working medium may be water, and correspondingly, the formed steam is water vapor, but it is not limited thereto.

[0055] Furthermore, the condensation test piece includes silicon wafer, copper, stainless steel or aluminum, etc., but is not limited thereto.

[0056] In some embodiments, the condensation pressure drop unit is disposed above the condensation chamber and is connected to the condensation chamber. The condensation pressure drop unit includes a condensation pipeline (for example, a condensation coil), a cooling medium and a circulation component (for example, a cooling circulation machine).

[0057] In the present invention, the condensation pressure drop unit is located above the condensation test unit and is directly connected to the condensation test unit, which effectively shortens the connecting pipeline between the condensation test unit and the condensation test unit to reduce heat loss, and realizes steady-state circulation of steam by controlling the temperature of the cold water circulating inside the condensation test unit. At the same time, a vacuum connection component (for example, a vacuum pipe joint) is arranged on it, which is directly connected to the vacuum pumping equipment, so as to facilitate precise control of the vacuum degree inside the condensation cavity and the main boiler.

[0058] Furthermore, the present invention realizes steady-state control of steam at different temperatures by controlling the heating power of the main heating boiler and the temperature of the condensing pressure drop unit.

[0059] Furthermore, in the present invention, the temperature control of the condensation pressure drop unit and the back of the condensation test unit is achieved by adjusting the temperature and flow rate of circulating cold water through a cooling circulation machine.

[0060] Furthermore, the condensation pressure drop unit is connected to the vacuum unit (for example, a vacuum pump) through a vacuum connection assembly.

[0061] Furthermore, the vacuum degree inside the device of the present invention can be precisely controlled by a vacuum oil pump or a vacuum pump group. The vacuum equipment is connected to the standard vacuum interface of the condensation pressure drop unit to meet the testing requirements under different vacuum degrees. In addition, according to the needs of the test, a low-temperature cold trap can be added at the front end of the vacuum pump group to protect the vacuum pump group.

[0062] In some embodiments, the condensation heat transfer performance characterization device also includes a data acquisition and monitoring unit, which is at least used to collect, monitor and process the temperature of the condensation test piece, the steam temperature in the condensation chamber, the pressure in the condensation chamber, and the liquid working fluid temperature in the dual boiler steam generating unit.

[0063] Furthermore, the data acquisition monitoring unit also includes a computer (PC), which is respectively connected to the first temperature control mechanism, the second temperature control mechanism, the temperature sensing mechanism, and the pressure sensing mechanism, and is at least used to monitor and process the collected data.

[0064] Furthermore, the sealing performance of the entire system is characterized before the experiment begins to ensure that the system is leak-proof; a vacuum unit is used to pre-remove non-condensable gases from the entire system before testing and to precisely control the amount of non-condensable gases in the system.

[0065] Furthermore, the present invention is applicable to the characterization of planar condensation effects in various steam environments, such as water vapor; and is applicable to the evaluation of condensation effects of various materials, such as silicon wafers, copper, stainless steel, aluminum, etc.

[0066] In summary, the present invention provides a miniaturized, compact and modular condensation heat transfer performance characterization device, which can minimize heat loss, and can simultaneously meet the steady-state test conditions of pure steam and extremely low non-condensable gas content with controllable content, and can obtain the condensation heat transfer performance and mass transfer performance of different samples under pure steam and extremely low non-condensable gas conditions.

[0067] The condensation heat transfer performance testing device of the present invention is easy to operate and can accurately control the non-condensable gas content in the system through the heating module of the double boiler.

[0068] The technical solution of the present invention is further described in detail below in conjunction with several preferred embodiments and drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0069] See also Figure 1 As shown, a condensation heat transfer performance characterization device in a typical embodiment of the present invention mainly includes a double-boiler steam generating unit, a condensation testing unit, a condensation pressure drop unit, a vacuum unit, a visual observation mechanism, and a data acquisition and monitoring unit.

[0070] The steam generating unit comprises a main heating boiler 12, an auxiliary heating boiler 10, a temperature sensor, a main heating boiler temperature controller 13, an auxiliary heating boiler temperature controller 9 and a vacuum connecting valve 11. The main heating boiler temperature controller 13 is connected to the main heating boiler 12, and the auxiliary heating boiler temperature controller 9 is connected to the auxiliary heating boiler 10. The working fluid is previously boiled and degassed in the auxiliary heating boiler 10 and then enters the main heating boiler 12 through the intermediate vacuum connecting valve 11. The upper end of the main heating boiler 12 is connected to the condensation test unit.

[0071] The condensation test unit is used to condense gaseous liquid working fluid, and includes a condensation shell, in which a Teflon insulation block 16 and a condensation test piece 21 are arranged, one side of the condensation shell and the insulation component are surrounded to form a condensation chamber 17, the condensation test piece is arranged at the center of the insulation component, and the surface of the condensation test piece is exposed in the condensation chamber, the condensation chamber is connected to the dual boiler steam generating unit, and the condensation test unit is vertically arranged.

[0072] The condensation test unit is composed of a cylindrical stainless steel metal shell, a middle Teflon insulation block 16, a cooling circulation channel 2 on the back of the condensation test piece 21, a front quartz glass observation window 18, a temperature sensor 19, and a pressure sensor 22. The condensation test piece 21 is embedded in the Teflon insulation block 16 to ensure one-dimensional axial steady-state heat conduction. The temperature sensor 19 records the steam temperature data in the condensation chamber 17 in real time, and the pressure sensor 22 records the pressure data in the condensation chamber 17 in real time. The high-speed microscope 20 is placed in front of the quartz glass observation window 18.

[0073] The cooling circulation channel 2 is connected to the cooling water tank 1, the cooling circulation machine 14 and the cooling circulation machine control valve 15 in sequence, and the cooling circulation machine control valve 15 is connected to the condensation test unit. The condensation test piece is cooled by controlling the temperature of the circulating cooling water, and the cooling water flows rapidly through the heat dissipation fins at the back of the test interface in a restricted manner to reach the required wall temperature.

[0074] The condensation pressure drop unit includes a built-in condensation coil 6, a cooling water tank 3, a cooling circulation machine 4, and a vacuum pipe joint 5. The condensation pressure drop unit is located above the condensation test unit and is directly connected to the condensation test unit, effectively shortening the connecting pipe between it and the condensation test unit to reduce heat loss, and realizing steady-state circulation of steam by controlling the temperature of the cold water circulating inside it. At the same time, a vacuum pipe joint is arranged on it, which is directly connected to the vacuum pump suction equipment, so as to facilitate precise control of the vacuum degree inside the condensation chamber and the main heating boiler.

[0075] The vacuum unit ensures that the entire system is in a vacuum state, and comprises a vacuum pump 7 , which is connected to a vacuum pipe connector 5 .

[0076] The data acquisition and monitoring unit includes temperature acquisition of the condensation test piece, temperature and pressure data acquisition of the steam in the condensation chamber, and temperature acquisition of the liquid working medium in the steam generating unit. The data acquisition device 8 is connected to a PC to collect, monitor and process the data.

[0077] The method for characterizing condensation heat transfer performance using the device of the present invention comprises the following steps:

[0078] Using a vacuum unit to evacuate the device, at least to remove non-condensable gases in the device;

[0079] Adding liquid working medium into the dual boiler steam generating unit and heating it to make it boil;

[0080] Allowing the gaseous liquid working medium to enter the condensation chamber and contact the condensation surface of the condensation test piece, while using a cooling circulation channel to cool the condensation test piece;

[0081] A condensation pressure drop unit is used to control the steady-state flow of steam and the vacuum degree inside the entire device;

[0082] Observe the condensate morphology and dynamic behavior of droplets of gaseous liquid working fluid on the surface of the condensation test piece through a visual observation structure; and

[0083] The temperature of the condensation test piece, the steam temperature in the condensation chamber, the pressure in the condensation chamber, and the temperature of the liquid working medium in the dual-boiler steam generating unit are collected, monitored and processed through the data acquisition and monitoring unit to characterize the condensation heat transfer performance of the functional interface.

[0084] Example 1

[0085] For pure steam condensation heat exchange experiment, the technical scheme is: first close the vacuum connection valve 11 between the main heating boiler 12 and the auxiliary heating boiler 10 of the steam generation unit, open the vacuum pipe joint 5 on the condensation pressure drop unit, start the vacuum pump 7 to evacuate the system, remove the non-condensable gas in the system, add deionized water to the auxiliary heating boiler 10 of the steam generation unit, heat and boil for 30 minutes, and reduce the water temperature to the preset steam temperature value. After evacuating to the limit of the vacuum pump, close the vacuum pipe joint 5, open the vacuum connection valve 11 between the main heating boiler 12 and the auxiliary heating boiler 10 of the steam generation unit, allow water to enter the main heating boiler 12, and close the vacuum connection valve 11. Turn on the heating control power of the main heating boiler, and at the same time start the cooling water circulation on the back of the condensation test unit. After the parameters such as pressure and steam temperature are stable, start the cooling water circulation of the condensation pressure drop unit to keep the pressure and steam temperature stable. The heat transfer performance of the functional interface is analyzed and evaluated through data acquisition and phenomenon recording.

[0086] Example 2

[0087] For the steam condensation heat exchange experiment containing air, the technical scheme is: first close the vacuum connection valve 11 between the main heating boiler 12 and the auxiliary heating boiler 10 of the steam generation unit, open the vacuum pipe joint 5 on the condensation pressure drop unit, start the vacuum pump 7 to evacuate the system, and after evacuating to the preset vacuum degree, add deionized water to the auxiliary heating boiler 10 of the steam generation unit, heat and boil for 30 minutes, and reduce the water temperature to the preset steam temperature value. After evacuating to the vacuum pump limit, close the vacuum pipe joint 5, open the vacuum connection valve 11 between the main heating boiler 12 and the auxiliary heating boiler 10 of the steam generation unit, allow water to enter the main heating boiler 12, and close the vacuum connection valve 11. Turn on the heating control power of the main heating boiler, and at the same time start the cooling water circulation on the back of the condensation test unit. After the parameters such as pressure and steam temperature are stable, start the cooling water circulation of the condensation pressure drop unit to keep the pressure and steam temperature stable. By calculating the percentage of air in the mixed gas, the technical scheme can be used to study the steam condensation heat transfer characteristics under different non-condensable gas contents.

[0088] It should be noted that, in this article, in general, the elements defined by the sentence "including..." do not exclude the existence of other identical elements in the steps, processes, methods or experimental equipment including the elements.

[0089] The above is only a preferred embodiment of the present invention. It should be noted that the local structure of the experimental device can be adjusted and refined according to specific requirements, which are not listed here one by one. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner. These simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A condensation heat transfer performance characterization device, characterized in that include: A double boiler steam generating unit, which is at least used to heat the liquid working medium, and the double boiler steam generating unit comprises a main heating mechanism, an auxiliary heating mechanism, a first temperature control mechanism, a second temperature control mechanism and a temperature sensing mechanism, a vacuum connection assembly is provided between the main heating mechanism and the auxiliary heating mechanism, the main heating mechanism is connected to the first temperature control mechanism, and the auxiliary heating mechanism is connected to the second temperature control mechanism; A condensation test unit, which is at least used to condense gaseous liquid working medium, comprises a condensation shell, in which a heat insulation component, a condensation test piece and a cooling circulation channel are arranged, one side of the condensation shell and the heat insulation component are surrounded to form a condensation chamber, the condensation test piece is arranged at the center of the heat insulation component, and the surface of the condensation test piece is exposed in the condensation chamber, the condensation chamber is connected to the double boiler steam generating unit, and the condensation test unit is arranged vertically; the contact surface between the heat insulation component and the gaseous liquid working medium has a spiral drainage channel; The condensation pressure drop unit is connected with the condensation test unit and a vacuum unit, and is used at least to control the steady-state flow of steam and the vacuum degree inside the entire device.

2. The condensation heat transfer performance characterization device according to claim 1, characterized in that: The condensation test unit is arranged above the main heating mechanism; and / or the condensation chamber has a plurality of connection ports respectively connected to the dual boiler steam generating unit and the condensation pressure drop unit, at least to make the surface of the condensation test piece in the vertical direction.

3. The condensation heat transfer performance characterization device according to claim 2, characterized in that: The condensation testing unit further comprises: A temperature sensing mechanism, which is used at least to measure the steam temperature in the condensation chamber and the temperature of the condensation test piece; a pressure sensing mechanism, which is used at least to measure the pressure in the condensation chamber; and The visual observation mechanism is arranged at a corresponding position of the observation window provided on the condensation shell.

4. The condensation heat transfer performance characterization device according to claim 1, characterized in that: The cooling circulation channel is in communication with a cooling medium, and the cooling medium is in communication with a condensing shell through a cooling circulation mechanism.

5. The condensation heat transfer performance characterization device according to claim 3, characterized in that: The visual observation mechanism includes a camera assembly and a light source, and the camera assembly is at least used to observe the condensate morphology of the gaseous liquid working medium on the surface of the condensation test piece and the dynamic behavior of the droplets.

6. The condensation heat transfer performance characterization device according to claim 1, characterized in that: The condensation test piece has a condensation surface and a back heat dissipation fin, wherein the condensation surface is exposed in the condensation chamber, and the back heat dissipation fin is in contact with the cooling medium in the cooling circulation channel.

7. The condensation heat transfer performance characterization device according to claim 3, characterized in that: The temperature sensing mechanism includes a plurality of thermocouples, and the thermocouples are arranged to intersect perpendicularly with the inner central axis of the condensation test piece.

8. The condensation heat transfer performance characterization device according to claim 1, characterized in that: The condensation pressure drop unit is arranged above the condensation chamber and communicated with the condensation chamber. The condensation pressure drop unit includes a condensation pipeline, a cooling medium and a circulation component.

9. The condensation heat transfer performance characterization device according to claim 8, characterized in that: The condensation pressure drop unit is connected to the vacuum unit through a vacuum connection assembly.

10. The condensation heat transfer performance characterization device according to claim 1, characterized in that Also includes: The data acquisition and monitoring unit is used at least to collect, monitor and process the temperature of the condensation test piece, the steam temperature in the condensation chamber, the pressure in the condensation chamber, and the temperature of the liquid working medium in the dual-boiler steam generating unit.

11. The condensation heat transfer performance characterization device according to claim 1, characterized in that: The liquid working medium includes water; and / or the condensation test piece includes silicon wafer, copper, stainless steel or aluminum.

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