Flue simulation test platform

Abstract

The present application provides a flue simulation test platform, comprising: an air flow circulation mechanism, the air flow circulation mechanism comprising: a pipeline, the pipeline defining a test flow channel, the test flow channel being provided with a test part for detachably mounting a heat exchange pipe, in the mounted state, the heat exchange pipe being covered in the pipeline; a simulation part, provided in the pipeline, being suitable for forming an air flow serving as a heat medium in the test flow channel, and making the air flow flow through the outside of the heat exchange pipe to form different heat exchange characteristics; a medium internal circulation mechanism, being in communication with the heat exchange pipe, being suitable for forming a medium circulation in the inside of the heat exchange pipe, so that the medium exchanges heat with the air flow and is cooled after the test; and a detection mechanism, comprising a plurality of detection parts provided in the air flow circulation mechanism and the medium internal circulation mechanism, being used for collecting important parameters such as the temperature, air pressure and flow rate of the air flow and the medium flowing through the heat exchange pipe before and after.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flue gas coolers for waste heat recovery, and more particularly to a flue simulation test platform for heat transfer-resistance data acquisition of a flue gas cooler. BACKGROUND

[0002] A flue gas cooler is a device installed downstream of a flue of a boiler tail for recovering waste heat of flue gas discharged by the boiler. In actual engineering applications, the complex flue structure and operating conditions of the flue gas cooler have an important influence on the heat transfer-resistance-depositing performance of the heat exchange pipe, which is an important technical challenge faced by the efficient operation of the flue gas cooler.

[0003] At present, the performance research of the flue gas cooler generally adopts a simplified treatment, ignores the influence of the flue structure, and analyzes and studies by using a uniform inlet flow field. However, in actual engineering, due to limited space, the flues before and after the flue gas cooler are mostly complex in structure, and the flow field is difficult to be uniformly distributed, so the existing research is difficult to guide actual engineering. Therefore, in order to research and optimize the heat transfer-resistance characteristics of the flue gas cooler such as spiral finned tube in actual engineering or provide data verification support for numerical simulation research, it is an indispensable technical means for improving the comprehensive performance of the flue gas cooler to simulate the flow-heat transfer characteristics of the actual flue by using the test means. SUMMARY

[0004] To solve the at least one technical problem in the prior art and other aspects, the present application provides a flue simulation test platform for simulating a use scene of a heat exchange equipment installed with heat exchange pipe and collecting data of temperature, air pressure and flow rate of air flow and medium caused by the heat exchange pipe based on a specific use scene.

[0005] The flue simulation test platform provided by the embodiments of the present application comprises: an air flow circulation mechanism comprising a pipeline, wherein the pipeline defines a test flow channel, and the test flow channel is provided with a test part for detachably installing a heat exchange pipe, and in the installed state, the heat exchange pipe is covered in the pipeline; a simulation part provided in the pipeline, which is suitable for forming an air flow serving as a heat medium in the test flow channel and making the air flow flow through the outside of the heat exchange pipe to form different heat exchange characteristics; a medium internal circulation mechanism in communication with the heat exchange pipe, which is suitable for forming a medium circulation in the inside of the heat exchange pipe so that the medium exchanges heat with the air flow; and a detection mechanism comprising a plurality of detection parts provided in the air flow circulation mechanism and the medium internal circulation mechanism, which is used for collecting at least one of temperature, air pressure and flow rate of the air flow and the medium before and after flowing through the heat exchange pipe.

[0006] According to an embodiment of the present disclosure, the simulation unit further comprises a control unit in communication with the simulation unit, the medium circulation unit and the detection unit, the control unit being adapted to collect the detection signal from the detection unit, and to adjust at least one of the temperature of the air flow, the flow rate of the air flow and the flow rate of the medium.

[0007] According to an embodiment of the present disclosure, the simulation unit comprises an air supply assembly installed on the pipeline and adapted to form the air flow in the test flow channel, and a heating assembly installed on the pipeline and adapted to adjust the temperature of the air flow so that the temperature of the air flow entering the simulation unit and / or the test unit is kept stable and higher than the temperature of the medium in the heat exchange pipe.

[0008] According to an embodiment of the present disclosure, the air supply assembly comprises a first air blower arranged in the pipeline and adapted to supply air along the circulation direction of the pipeline so that the air in the test flow channel forms the air flow, and a second air blower arranged outside the pipeline and in communication with the test flow channel and adapted to supply external air into the test flow channel to supplement the air flow formed in the test flow channel, wherein the air supply directions of the first air blower and the second air blower are consistent with the circulation direction of the air flow.

[0009] According to an embodiment of the present disclosure, the heating assembly is installed between the first air blower and the second air blower.

[0010] According to an embodiment of the present disclosure, the heating assembly comprises a modular electric heating resistance wire.

[0011] According to an embodiment of the present disclosure, the simulation unit further comprises an air inlet simulation assembly which is detachably installed upstream of the test unit and adapted to adjust the flue form and / or the air distribution form upstream of the heat exchange pipe.

[0012] According to an embodiment of the present disclosure, the air inlet simulation assembly comprises a plurality of flue simulation members which are configured in at least one of a right-angle flue structure, an inclined flue structure and a variable cross-section flue structure, and the plurality of flue simulation members are installed on the pipeline alternatively or sequentially.

[0013] According to an embodiment of the present disclosure, the air inlet simulation assembly further comprises a plurality of air distribution simulation members which are configured in at least one of a uniform incoming flow air distribution structure and a non-uniform incoming flow air distribution structure, and the plurality of air distribution simulation members are installed on the pipeline alternatively or sequentially.

[0014] According to an embodiment of the present disclosure, the pipeline further comprises an inlet transition section arranged upstream of the air inlet simulation assembly, the inlet transition section being configured to gradually expand the cross-sectional area from upstream to downstream of the air flow so as to increase the ventilation volume of the air flow entering the air inlet simulation assembly.

[0015] According to an embodiment of the present disclosure, the pipeline further comprises an outlet transition section arranged downstream of the test section, the outlet transition section being configured to gradually decrease the cross-sectional area of the gas flow from upstream to downstream, so as to improve the wind pressure of the gas flow out of the heat exchange pipe.

[0016] According to an embodiment of the present disclosure, the medium circulation mechanism comprises a gas circulation section with a gas medium and a liquid circulation section with a liquid medium, both of which are in communication with the input end and the output end of the heat exchange pipe and are configured to selectively conduct with the heat exchange pipe, so that the gas medium or the liquid medium forms a medium circulation in the heat exchange pipe.

[0017] According to an embodiment of the present disclosure, the detection mechanism comprises a first detection section arranged at positions upstream and downstream of the heat exchange pipe in the test flow channel, for detecting the temperature, wind pressure and flow rate of the gas flow before and after flowing through the heat exchange pipe; and a second detection section arranged at positions upstream and downstream of the heat exchange pipe in the medium circulation mechanism, for detecting the temperature, wind pressure and flow rate of the medium before and after flowing through the heat exchange pipe.

[0018] According to an embodiment of the present disclosure, the first detection section comprises a first front detection group arranged upstream of the heat exchange pipe in the test flow channel, suitable for detecting the temperature, wind pressure and flow rate of the gas flow before flowing through the heat exchange pipe; and a first rear detection group arranged downstream of the heat exchange pipe in the test flow channel, suitable for detecting the temperature and wind pressure of the gas flow after flowing through the heat exchange pipe.

[0019] According to an embodiment of the present disclosure, the second detection section comprises a second front detection group arranged upstream of the heat exchange pipe in the medium circulation mechanism, suitable for detecting the temperature, pressure and flow rate of the medium before flowing through the heat exchange pipe; and a second rear detection group arranged downstream of the heat exchange pipe in the medium circulation mechanism, suitable for detecting the temperature and wind pressure of the medium after flowing through the heat exchange pipe.

[0020] According to the flue simulation test platform provided by the application, the air flow circulation mechanism provides a pipeline for connecting the heat exchange pipe, the simulation part and the test flow channel defined in the pipeline are communicated, and the air flow in the pipeline is used to simulate the flue gas. The medium circulation mechanism is communicated with the heat exchange pipe, and is used to introduce and discharge the medium into and out of the heat exchange pipe to exchange heat with the air flow as the heat medium. The detection mechanism is provided with multiple detection parts for collecting at least one of the temperature, air pressure and flow rate of the air flow before and after the heat exchange pipe and the medium, and the temperature change amount, air pressure change amount and flow rate before entering the heat exchange pipe are used as the data for designing the heat exchange pipe. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a module connection diagram of the flue simulation test platform according to an illustrative embodiment of the application;

[0022] Figure 2 is Figure 1 is a perspective view of the air inlet simulation assembly and part of the test part of the illustrative embodiment shown in

[0023] Figure 3 is Figure 1 is a perspective view of the flue simulation part of the illustrative embodiment shown in Figure 3 a is a first flue simulation part of a right-angle flue structure, Figure 3 b is a second flue simulation part of an inclined flue structure, Figure 3 c is a third flue simulation part of a variable cross-section flue structure;

[0024] Figure 4 is Figure 1 is a structure diagram of the air distribution simulation part of the illustrative embodiment shown in Figure 4 a is a cross-sectional view of the air distribution simulation part of a uniform inflow air distribution structure, Figure 4 b is a cross-sectional view of the air distribution simulation part of a non-uniform inflow air distribution structure;

[0025] Figure 5 is Figure 1 is a schematic diagram of the detection position of the first detection part and the second detection part of the flue simulation test platform of the illustrative embodiment shown in

[0026] Figure 6 is Figure 5 is a perspective view of the monitoring point of the detection position of the flue simulation test platform of the illustrative embodiment shown in

[0027] Figure 7 is Figure 1 is a perspective view of the heat exchange pipe of the flue simulation test platform of the illustrative embodiment shown in

[0028] In the drawings, the meanings of the reference signs are as follows:

[0029] 1. A detection mechanism;

[0030] 11. A first front detection group;

[0031] 111. A flow rate detection member;

[0032] 112. A wind pressure detection member;

[0033] 113. A temperature detection member;

[0034] 12. A first back detection group;

[0035] 13. A second front detection group;

[0036] 14. A second back detection group;

[0037] 2. A medium internal circulation mechanism;

[0038] 21. A gas safety valve;

[0039] 22. A liquid safety valve;

[0040] 23. A first cooling device;

[0041] 24. A second cooling device;

[0042] 25. A third fan;

[0043] 26. A liquid tank;

[0044] 27. A pump;

[0045] 3. A control mechanism;

[0046] 4. An air flow circulation mechanism;

[0047] 41. A second fan;

[0048] 42. A heating assembly;

[0049] 43. A first fan;

[0050] 44. An air inlet simulation assembly;

[0051] 441. A first flue simulation member;

[0052] 442. A second flue simulation member;

[0053] 443. A third flue simulation member;

[0054] 444. A first air distribution simulation member;

[0055] 445. A second air distribution simulation member;

[0056] 45. A test section;

[0057] 46. an inlet transition section;

[0058] 47. an outlet transition section; and

[0059] 5. a heat exchange tube. DETAILED DESCRIPTION

[0060] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to specific embodiments and with reference to the drawings.

[0061] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used herein, the term "comprising" or "comprises" or "including" or "includes" or "containing" or "contains" or "has" or "having" or the like is used in the inclusive sense of "including" and not in the exclusive or exhaustive sense.

[0062] All terms used herein including technical and scientific terms have the meanings commonly understood by one of ordinary skill in the art unless otherwise defined. It should be noted that the use of any terms herein should not be interpreted to limit the scope of the present application, but rather the scope of the present application is defined by the claims.

[0063] In situations where similar terminology is used for similar items, one of ordinary skill in the art would understand the terminology to have a meaning in accordance with the description of the specification and would interpret the description of this specification in the context of this common terminology.

[0064] Figure 1 is a module connection diagram of a flue simulation test platform according to an exemplary embodiment of the present application.

[0065] The present application provides a flue simulation test platform, such as Figure 1As shown, the device comprises a gas flow circulation mechanism 4, a medium circulation mechanism 2 and a detection mechanism 1. The gas flow circulation mechanism 4 comprises a pipeline and a simulation part. The pipeline defines a test flow channel, and the test flow channel is provided with a test part 45 for detachably mounting the heat exchange pipe 5. In the mounted state, the heat exchange pipe 5 is covered in the pipeline. The simulation part is arranged in the pipeline and is suitable for forming a gas flow serving as a heat medium in the test flow channel and making the gas flow pass through the outside of the heat exchange pipe 5 to form different heat exchange characteristics (such as temperature, flow rate, air pressure, air distribution mode and flue structure of the gas flow, which are the key heat exchange characteristics).

[0066] In an illustrative embodiment, the pipeline is configured to include but not limited to a rectangular cross-sectional structure.

[0067] Further, the pipeline forms a circular structure connected at the head and tail.

[0068] Further, a part of the straight pipeline region in the pipeline is selected as the test part 45, and the two ends of the test part 45 are sealingly connected with the pipeline (including but not limited to at least one of riveting, welding, bolt connection and flange connection).

[0069] In an illustrative embodiment, the test part 45 of the pipeline includes but not limited to a cuboid structure.

[0070] In detail, the size of the test part 45 includes but not limited to being configured to be 800 mm high x 600 mm wide x 1500 mm long, which is suitable for accommodating the heat exchange pipe 5.

[0071] Further, the test part 45 is provided with a mounting hole for leading out the connecting part of the heat exchange pipe 5 and the medium circulation mechanism 2.

[0072] Further, the mounting hole is provided with an interface of the medium circulation mechanism 2 for connecting with the heat exchange pipe 5.

[0073] In an illustrative embodiment, the detection part of the detection mechanism 1 is used to collect the temperature, air pressure and flow rate of the gas flow and the medium flowing before and after the heat exchange pipe 5.

[0074] In such an embodiment, the air flow circulation mechanism 4 provides a pipeline for accessing the heat exchange pipe 5, and the simulation part and the test flow passage defined in the pipeline are in communication, for forming the air flow simulating the flue gas in the pipeline. The medium circulation mechanism 2 and the heat exchange pipe 5 are in communication, for introducing and discharging the medium into and out of the heat exchange pipe 5, to exchange heat with the air flow as the heat medium. The detection mechanism 1 is provided with a plurality of detection parts for collecting the temperature, air pressure and flow rate of the air flow before and after flowing through the heat exchange pipe 5, and the temperature change amount, air pressure change amount and flow rate before entering the heat exchange pipe 5 are taken as the data for designing the heat exchange pipe 5. In this way, different test conditions of temperature, air pressure, flow rate, flue structure and air distribution form can be constructed in the flue simulation test platform, for simulating the actual use scene of the heat exchange pipe 5 in the flue gas cooler, to obtain the data of the heat exchange pipe 5 in different use scenes.

[0075] According to an embodiment of the present disclosure, as shown in Figure 1 The flue simulation test platform further comprises a control mechanism 3 in communication connection with the simulation part, the medium circulation mechanism 2 and the detection mechanism 1. The control mechanism 3 is adapted to collect the detection signals of the detection mechanism 1, to adjust at least one of the temperature of the air flow, the flow rate of the air flow and the flow rate of the medium.

[0076] According to an embodiment of the present disclosure, as shown in Figure 1 The simulation part comprises an air induction assembly and a heating assembly 42. The air induction assembly is installed on the pipeline and is adapted to form the air flow in the test flow passage. The heating assembly 42 is installed on the pipeline, for adjusting the temperature of the air flow, so that the temperature of the air flow entering the simulation part or the experimental part remains stable and is higher than the temperature of the medium in the heat exchange pipe 5.

[0077] According to an embodiment of the present disclosure, as shown in Figure 1 The air induction assembly comprises a first air fan 43 and a second air fan 41. The first air fan 43 is arranged in the pipeline and is adapted to send air along the circulation direction of the pipeline, so that the gas in the test flow passage forms the air flow. The second air fan 41 is arranged outside the pipeline and is in communication with the test flow passage, and is adapted to send the external gas into the test flow passage, to supplement the air flow formed in the test flow passage. The air sending direction of the first air fan 43 and the second air fan 41 is consistent with the circulation direction of the air flow.

[0078] According to an embodiment of the present disclosure, as shown in Figure 1 The heating assembly 42 is installed between the first air fan 43 and the second air fan 41.

[0079] According to an embodiment of the present disclosure, as shown in Figure 1 The heating assembly 42 comprises but is not limited to a modular electric heating resistance wire.

[0080] In an exemplary embodiment, the heating assembly comprises, but is not limited to, a plurality of modular electric heating resistance wires.

[0081] In detail, based on the required temperature adjustment, a corresponding number of modular electric heating resistance wires can be turned on according to the appropriate heating power.

[0082] In such an embodiment, before the start of the test, the first fan 43 and the heating furnace can be operated to form a circulating air flow in the pipeline. The air flow passes through the heating furnace in sequence during the circulation to form stable temperature conditions (for example, the temperature at the inlet of the test section 45 meets the test temperature). Since the pipeline cannot be completely sealed, air loss will occur during the circulation, and the second fan 41 needs to be operated to supply air to the pipeline to supplement the air flow, so that the air flow maintains a substantially stable air pressure and air speed during the process of passing through the test section 45 in sequence. After the temperature, air pressure and air speed all meet the test conditions, the test can be started. During the test, due to the influence of the air flow on the heat exchange with the heat exchange pipe 5 and the new air supplied, the heating furnace arranged between the first fan 43 and the second fan 41 can be used to heat the part of the air flow, so as to maintain the air pressure, air speed and temperature conditions in a substantially stable state during the test.

[0083] In an exemplary embodiment, the control mechanism 3 comprises, but is not limited to, at least one of an industrial computer, an editable logic controller, and a board card.

[0084] In detail, the control mechanism 3 is in communication connection with the first fan 43, the second fan 41 and the modular electric heating resistance wire, and is adapted to output control signals to the first fan 43, the second fan 41 and the modular electric heating resistance wire to control the air volume and air flow in the pipeline.

[0085] In an exemplary embodiment, the control of the first fan 43 and the second fan 41 is based on the following formula 1:

[0086]

[0087] In formula 1, P represents the fan power (kw); Q represents the air volume (m 3 / h); p represents the air pressure (Pa); η1 represents the mechanical efficiency (0.95-0.98), which is taken as 0.98 here; and η2 represents the fan efficiency (0.72-0.8), which is taken as 0.75 here.

[0088] Further, the flue simulation test platform allows the test air speed to be in the range of 2-7 m / s, and the selected fan power includes but is not limited to P=5 kw, and the test air pressure includes but is not limited to p=1100-3850 Pa.

[0089] In such an embodiment, the control mechanism 3 can adjust the air speed and air pressure in the pipeline based on the power adjustment of the first fan 43 and / or the second fan 41, so as to simulate the flue gas under different air speed and air pressure conditions.

[0090] In an exemplary embodiment, the heating furnace control is in accordance with the following formula 2:

[0091]

[0092] In formula 2, Q is the required heating power (kw); c p is the specific volume of gas at constant pressure (kJ / (kg·℃)); q m is the air mass flow (kg / h); t2, t1 is the air temperature before and after the heating furnace (℃).

[0093] t2, t1 in formula 2 can be implemented by setting temperature sensors at upstream and downstream positions of the heating furnace.

[0094] In such an embodiment, the control mechanism 3 can adjust the temperature of the air flow in the pipeline based on the power adjustment of the heating furnace, so as to simulate the flue gas under different temperature conditions.

[0095] Figure 2 is Figure 1 The perspective view of part of the air inlet simulation assembly and the test part of the exemplary embodiment shown in

[0096] According to embodiments of the present disclosure, as Figure 1 and Figure 2 shown, the simulation part further comprises an air inlet simulation assembly 44. The air inlet simulation assembly 44 is detachably installed upstream of the test part 45, for adjusting the flue form and / or air distribution form upstream of the heat exchange pipe 5. This can be used to simulate the flue structure and air distribution form of the heat exchange pipe in actual use scenarios.

[0097] Figure 3 is Figure 1 The perspective view of the flue simulation piece of the exemplary embodiment shown in Figure 3 a is a first flue simulation piece 441 of a right-angle flue structure, Figure 3 b is a second flue simulation piece 442 of an inclined flue structure, Figure 3 c is a third flue simulation piece 443 of a variable cross-section flue structure.

[0098] According to embodiments of the present disclosure, as Figure 3As shown, the intake simulation assembly 44 includes multiple flue simulation components. These flue simulation components are constructed as at least one of a right-angle flue structure, an inclined flue structure, and a variable cross-section flue structure. Multiple flue simulation components are selectively or sequentially installed on the pipeline. This allows for the simulation of single or combined flue structures of heat exchanger fittings in actual usage scenarios.

[0099] In one illustrative embodiment, such as Figure 3 As shown in a, the first flue simulation component 441 is constructed as a right-angle flue structure.

[0100] In another illustrative embodiment, such as Figure 3 As shown in b, the second flue simulation component 442 is constructed as an inclined flue structure.

[0101] In another illustrative embodiment, such as Figure 3 As shown in c, the third flue simulation component 443 is constructed as a variable cross-section flue structure.

[0102] Furthermore, based on the three flue simulation components in the above illustrative embodiments, the positions of the pipelines for connecting with the three flue simulation components are provided with interfaces for connecting with the corresponding flue simulation components (the specific interface form should preferably meet the requirements for connecting with the flue simulation components and for the sealing of the pipeline).

[0103] Furthermore, the connection methods between the flue simulation component and the pipeline include, but are not limited to, bolt connection, flange connection, snap-fit ​​connection, and one of other detachable installation methods.

[0104] Furthermore, a rectifier mesh is installed in the pipe between the flue simulation component and the test section 45 to regulate the uniformity of the airflow entering the heat exchange tube 5.

[0105] In this implementation, by using replaceable flue simulation components, different flue structures can be constructed at the upstream position of the pipeline adjacent to the test section 45 to simulate the heat exchange of the heat exchange tube 5 under different flue structure conditions, so as to collect data on the impact of the flue structure on the heat exchange tube 5.

[0106] Figure 4 yes Figure 1 The diagram shown illustrates the structure of the air distribution simulation component in a schematic embodiment. Figure 4 'a' is a cross-sectional view of the air distribution simulation component with a uniform airflow structure. Figure 4 b is a cross-sectional view of the air distribution simulation component of the non-uniform air distribution structure.

[0107] According to embodiments of this disclosure, such as Figure 4As shown, the air inlet simulation assembly 44 further comprises a plurality of air distribution simulation members. The air distribution simulation members are configured to at least one of uniform flow air distribution structure and non-uniform flow air distribution structure, and the plurality of air distribution simulation members are alternatively or sequentially installed on the pipeline. In this way, the single air distribution form or the combined air distribution form of the heat exchange pipe in the actual use scene can be simulated.

[0108] In an exemplary embodiment, as shown in a of FIG. 4, Figure 4 The first air distribution simulation member 444 comprises a flow straightening net arranged in a direction perpendicular to the test flow channel, so as to straighten the air flow through the air inlet simulation assembly 44. It should be understood that the embodiments of the present disclosure are not limited thereto.

[0109] For example, the air flow can be straightened by arranging a flow uniformizing plate in the air distribution simulation member.

[0110] In another exemplary embodiment, as shown in b of FIG. 4, Figure 4 The second air distribution simulation member 445 comprises a plate structure arranged in a direction perpendicular to the flow direction of the air flow and diffusing in the cross-sectional direction from upstream to downstream. The air flow entering the test part 45 forms a non-uniform flow.

[0111] In such an embodiment, by replacing the air distribution simulation members, the upstream position of the pipeline adjacent to the test part 45 can be configured into different air distribution structures, so as to simulate the heat exchange of the heat exchange pipe 5 under the conditions of uniform flow and non-uniform flow, and collect data of the influence of different flow conditions on the heat exchange pipe 5.

[0112] According to an embodiment of the present disclosure, as shown in Figure 2 The pipeline further comprises an inlet transition section 46 arranged upstream of the air inlet simulation assembly 44. The inlet transition section 46 is configured to gradually expand the cross-sectional area of the air flow from upstream to downstream, so as to adjust the uniformity of the air flow entering the air inlet simulation assembly 44.

[0113] According to an embodiment of the present disclosure, as shown in Figure 2 The pipeline further comprises an outlet transition section 47 arranged downstream of the test part 45. The outlet transition section 47 is configured to gradually reduce the cross-sectional area of the air flow from upstream to downstream.

[0114] According to an embodiment of the present disclosure, as shown in Figure 1 As shown in FIG. 5, the medium internal circulation mechanism 2 comprises a gas circulation part having a gas medium and a liquid circulation part having a liquid medium. The gas circulation part and the liquid circulation part are in communication with the input end and the output end of the heat exchange pipe 5, and are configured to be selectively communicated with the heat exchange pipe 5, so that the gas medium or the liquid medium forms a medium circulation in the heat exchange pipe 5. In this way, the temperature change heat absorption in the heat exchange pipe or the constant temperature working condition of the wall surface two-phase boiling by adjusting the internal pressure can be realized, and important test verification data for simulation and emulation can be provided.

[0115] In an exemplary embodiment, the gas circulation part comprises a third fan 25 and a gas valve (with air as the gas source), the gas outlet of the third fan 25 is communicated with the input of the heat exchange pipe 5, and the gas valve is used to cut off or open the gas path between the third fan 25 and the heat exchange pipe 5.

[0116] Further, a first cooling device 23 (such as a gas cooler) for cooling the gas medium is installed between the third fan 25 and the output of the heat exchange pipe 5, so that the heat-exchanged gas medium is cooled to the initial temperature before the last cycle.

[0117] Still further, the gas circulation part further comprises a gas safety valve 21 arranged in the gas path for pressure relief.

[0118] In an exemplary embodiment, the liquid circulation part comprises a liquid tank 26 storing a liquid source (including but not limited to any one of water, oil and coolant), a pump 27 and a liquid valve, the liquid outlet of the pump 27 is communicated with the input of the heat exchange pipe 5, and the liquid valve is used to cut off or open the liquid path between the pump 27 and the heat exchange pipe 5.

[0119] Further, a second cooling device 24 (such as a liquid cooler) for cooling the liquid medium is installed between the liquid tank 26 and the output of the heat exchange pipe 5, so that the heat-exchanged liquid medium is cooled to the initial temperature before the last cycle.

[0120] Still further, the liquid circulation part further comprises a liquid safety valve 22 arranged in the liquid path for pressure relief.

[0121] In an exemplary embodiment, the control mechanism 3 is communicatively connected with the third fan 25 and the pump 27 to control the flow of the gas medium or the liquid medium in the circulation process.

[0122] In an exemplary embodiment, the control of the pump 27 is based on the following formula 3:

[0123] P b = Q m Hρgη3 Formula 3

[0124] In formula 3, P b is the pump power (W); Q m is the liquid medium flow rate (m 3 / s); H is the head (m); ρ is the liquid medium density (kg / m 3 ); g is the gravitational acceleration (9.8 m / s 2 ); and η3 is the pump efficiency, generally 0.75-0.85.

[0125] In another illustrative embodiment, the control of the third fan 25 can refer to equation 1.

[0126] In an illustrative embodiment, since the medium is cooled after heat exchange, the output of the heat exchange pipe 5 is higher than the initial temperature of the last cycle, so the medium needs to be cooled to reduce the temperature of the medium to the initial temperature before the next cycle.

[0127] In detail, the design of the second cooling device 24 is as follows equation 4:

[0128] c p1 q m1 (t′1-t′2)=c p2 q m2 (t″2-t″1) Equation 4

[0129] In equation 4, c p1 is the specific volume of the medium outside the pipe at constant pressure, q m1 is the flow rate of the medium outside the pipe (air flow), t′1 and t′2 are the temperatures of the medium outside the pipe (air flow) before and after the heat exchange pipe 5; c p2 is the specific volume of the medium inside the pipe (liquid medium) at constant pressure, q m2 is the flow rate of the medium inside the pipe (liquid medium), t″1 and t″2 are the temperatures of the medium inside the pipe (liquid medium) before and after the heat exchange pipe 5.

[0130] In another illustrative embodiment, for the cooling method of the third fan 25 introducing air as a gas medium, the heat-exchanged gas medium can be directly discharged to the external air environment, and new air can be sent by the third fan 25 during the next cycle. Since the air temperature of the external air environment is basically consistent within a certain period of time, the influence of the external air temperature on the test can be ignored. If the gas medium is sealed in the gas circuit, a cooling pipe with cooling liquid can be used to cool the gas medium.

[0131] It should be noted that any cooling device in the art that can be used to cool the gas medium can be selected as appropriate, and will not be expanded in detail.

[0132] In such an embodiment, the gas circulation part and the liquid circulation part are selectively connected to the heat exchange pipe 5 by a gas valve or a liquid valve, so that the gas medium or the liquid medium exchanges heat with the gas flow outside the heat exchange pipe 5 through the inside of the heat exchange pipe 5, to simulate the heat exchange of the heat exchange pipe 5 under different medium conditions. The cooling device (the first cooling device 23 and / or the second cooling device 24) arranged in the gas circulation part and the liquid circulation part is used to cool the gas medium or the liquid medium, so that the gas medium and the liquid medium are maintained at approximately the same temperature in the next cycle entering the input end of the heat exchange pipe 5. The data of the influence of different media on the heat exchange pipe 5 is collected.

[0133] Figure 5 is Figure 1 a schematic diagram of the detection positions of the first detection part and the second detection part of the flue simulation test platform of the schematic embodiment shown in FIG. 1.

[0134] According to an embodiment of the present disclosure, as shown in Figure 5 the detection mechanism 1 includes a first detection part and a second detection part. The first detection part is arranged at positions upstream and downstream of the heat exchange pipe 5 in the test flow channel, and is used to detect the temperature, air pressure and flow rate of the gas flow before flowing through the heat exchange pipe 5. The second detection part is arranged at positions upstream and downstream of the heat exchange pipe 5 in the medium internal circulation mechanism 2, and is used to detect the temperature, air pressure and flow rate of the medium before flowing through the heat exchange pipe 5.

[0135] According to an embodiment of the present disclosure, as shown in Figure 5 the first detection part includes a first front detection group 11 and a first rear detection group 12. The first front detection group 11 is arranged at a position upstream of the heat exchange pipe 5 in the test flow channel, and is suitable for detecting the temperature, air pressure and flow rate of the gas flow before flowing through the heat exchange pipe 5. The first rear detection group 12 is arranged at a position downstream of the heat exchange pipe 5 in the test flow channel, and is suitable for detecting the temperature and air pressure of the gas flow after flowing through the heat exchange pipe 5.

[0136] According to an embodiment of the present disclosure, as shown in Figure 5 the second detection part includes a second front detection group 13 and a second rear detection group 14. The second front detection group 13 is arranged at a position upstream of the heat exchange pipe 5 in the medium internal circulation mechanism 2, and is suitable for detecting the temperature, air pressure and flow rate of the medium before flowing through the heat exchange pipe 5. The second rear detection group 14 is arranged at a position downstream of the heat exchange pipe 5 in the medium internal circulation mechanism 2, and is suitable for detecting the temperature and air pressure of the medium after flowing through the heat exchange pipe 5. In this way, the measured temperature and pressure data provide an important reference for subsequent performance analysis.

[0137] In a schematic embodiment, as shown in Figure 2As shown, the first front detection group 11 is located between the intake simulation assembly 44 and the test section 45. The first rear detection group 12 is located on the pipeline adjacent to the test section 45.

[0138] In detail, the first pre-detection group of 11 items includes, but is not limited to, temperature acquisition devices, air pressure acquisition devices, and flow velocity acquisition devices, to collect the temperature, pressure, and flow velocity of the airflow entering the heat exchange tube 5, respectively.

[0139] Furthermore, such as Figure 5 As shown, the first post-detection group 12 includes, but is not limited to, temperature acquisition devices and wind pressure acquisition devices.

[0140] Furthermore, the velocity, air pressure, and temperature sensors are arranged sequentially from upstream to downstream. This reduces interference caused by airflow passing through the upstream sensors, thereby improving detection accuracy.

[0141] In one illustrative embodiment, such as Figure 5 As shown, the second front detection group 13 is located adjacent to the input end of the heat exchange tube 5 of the medium circulation mechanism 2. The second rear detection group 14 is located adjacent to the output end of the heat exchange tube 5.

[0142] In detail, the second pre-detection group of 13 items includes, but is not limited to, temperature acquisition devices and pressure acquisition devices, to collect the temperature and pressure of the medium (including liquid medium and gas medium) entering the heat exchange tube 5 respectively.

[0143] Furthermore, the second post-detection group 14 includes, but is not limited to, the use of temperature acquisition devices and pressure acquisition devices to collect the temperature and pressure of the medium (including liquid medium and gas medium) after the output heat exchange tube 5.

[0144] Furthermore, the pressure and temperature sensors are arranged sequentially from upstream to downstream. This reduces the interference caused by airflow passing through the upstream sensors, thereby improving detection accuracy.

[0145] In this implementation, the temperature values ​​collected at the four detection locations can be used to calculate the heat loss of the airflow and medium during the circulation process; the collected pressure values ​​can be used to obtain the characteristic pressure at the center of the cross-section, so as to calculate the cross-sectional pressure through regional weighting; and the flow velocity values ​​can be used to determine the uniformity of the airflow.

[0146] Figure 6 yes Figure 5 A perspective view of the monitoring points at the detection location of the flue simulation test platform shown in the schematic embodiment.

[0147] In an exemplary embodiment, each detection group (including the first front detection group 11, the first rear detection group 12, the second front detection group 13, and the second rear detection group 14) includes a plurality of detection members.

[0148] In detail, as shown in FIG. 1, a plurality of detection points are arranged along the pipeline (including the pipeline and the flow passage of the medium circulation mechanism 2) at the detection positions where the detection groups are installed. Figure 6

[0149] Further, as shown in FIG. 2, the detection points include, but are not limited to, nine detection points. Figure 6

[0150] Further, the nine detection points are divided into three rows according to the cross-sectional direction of the pipeline, and the three rows of detection points are sequentially arranged in a stepped manner along the flow direction of the airflow or the medium, and each row includes three detection points arranged side by side.

[0151] Further, a plurality of flow rate detection members 111, air pressure detection members 112, and temperature detection members 113 for collecting temperature, air pressure (or medium pressure), and flow rate are arranged in each detection point.

[0152] In an exemplary embodiment, the temperature collection member includes, but is not limited to, a thermocouple, the air pressure / pressure collection member includes, but is not limited to, a gas pressure gauge (liquid pressure gauge), and the flow rate collection assembly includes, but is not limited to, a turbine flowmeter.

[0153] In such an embodiment, since the state of the fluid changes frequently and the change on the fluid interface is relatively complex, the plurality of detection points arranged at the detection positions can respectively collect corresponding data, so as to obtain average values as measurement data or select a plurality of data to obtain measurement data in data processing. In this way, the reliability and accuracy of the collected data can be improved.

[0154] In an exemplary embodiment, the flue simulation test platform further includes a protection mechanism.

[0155] In detail, the protection mechanism is in communication connection with the measurement mechanism and the control mechanism 3.

[0156] For example, the protection mechanism is in communication connection with the first detection part and the second detection part, and is used to collect detection information in the airflow circulation mechanism 4 and the medium circulation mechanism 2, and to cut off the power supply of the heating assembly 42 and / or open the gas safety valve 21 or the liquid safety valve 22 when an over-temperature (temperature higher than a preset value) or an over-pressure (pressure higher than a preset value) state occurs.

[0157] Further, the protection mechanism further includes a liquid level detection assembly arranged in the liquid tank 26, which is used to alarm when the liquid in the liquid tank 26 is higher than an upper limit or lower than a lower limit. It should be understood that the embodiments of the present disclosure are not limited thereto.​​

[0158] For example, the protection mechanism can also adopt any device for protecting the flue simulation test platform in the form of electrical safety, pressure safety and other safety forms.

[0159] Figure 7 is a perspective view of the heat exchange pipe of the flue simulation test platform of the illustrative embodiment. Figure 1

[0160] In an illustrative embodiment, the heat exchange pipe 5 arranged in the flue simulation test platform can refer to as shown in Figure 7

[0161] In an illustrative embodiment, the test for the heat exchange pipe 5 includes a pre-test stage, a test stage and a post-test stage.

[0162] Step S100: The pre-test stage includes:

[0163] S101: Check the flow passability and sealing of the pipeline of the air flow circulation mechanism 4 and the medium internal circulation mechanism 2.

[0164] S102: Check the equipment integrity and line safety of the detection mechanism 1, the control mechanism 3 and the protection mechanism.

[0165] S103: Select and install the air inlet simulation assembly 44 as shown in Figure 3 and Figure 4 and connect to the pipeline.

[0166] S104: Check that the first detection part and the second detection part of the detection mechanism 1 are connected to the appropriate detection position.

[0167] Step S110: The test stage includes:

[0168] Step S111: Turn on the first fan 43 and the heating furnace, detect the air parameters (including temperature, air pressure and flow rate) of the air flow through the detection mechanism 1 until the air parameters are stable.

[0169] Step S112: Connect the medium internal circulation mechanism 2 to the heat exchange pipeline to introduce liquid medium or gas medium into the heat exchange pipeline, so that the medium participates in heat exchange, detect the medium parameters (including temperature, pressure and flow rate) of the medium through the detection mechanism 1 until the medium parameters are stable, and detect and record the required data about the medium.

[0170] Step S113: Stop the test after the test reaches the predetermined time and / or the required data acquisition of the medium is completed.

[0171] Further, before step S113, the test stage further includes:

[0172] ​​Step S114: Adjust the power of the heating furnace to adjust (e.g., increase) the temperature of the air flow. And / or:

[0173] Step S115: Turn on and adjust the power of the second motor to adjust the flow rate of the air flow and / or adjust (e.g., decrease) the temperature of the air flow. To change the conditions of the test.

[0174] Step S120: The post-test phase includes.

[0175] Step S121: Sequentially turn off the power supply of the heating furnace, turn off the first fan 43, turn off the medium internal circulation mechanism 2, and turn off all electrical equipment of the flue simulation test platform.

[0176] Step S122: Input the recorded data into the lower computer for subsequent processing.

[0177] In an illustrative embodiment, the data obtained in step S122 can be calculated by a compiled VC++ program, to obtain corresponding parameters and analyze the heat transfer-resistance characteristics of the heat exchanger.

[0178] For example, the separate thermal resistance method is used as the calculation method, and a corresponding program is written using VC++, and by using the state parameters and property parameters of the fluid obtained through actual tests, j factor and f factor are calculated, and the heat transfer-resistance characteristics of the heat exchange pipe 5 are evaluated. The formulas of j factor and f factor are as follows:

[0179]

[0180]

[0181] In formula 5 and formula 6, Δp is the pressure drop of the air side at the inlet and outlet, l f is the fin length, ρ o is the density of the fluid outside the tube (air) (which changes with temperature, and generally takes the density at the average temperature of the fluid outside the tube), v max is the velocity at the minimum free flow area of the air side (the density of the air changes with temperature, and the flow velocity is different at different temperatures, and the flow velocity is the largest when the temperature is higher and the flow area is smaller), D c is the outer diameter of the fin ring. It should be understood that embodiments of the present disclosure are not limited thereto.

[0182] For example, the parameters obtained through step S122 can also be used to calculate the Nusselt number, the Euler number, and the heat transfer coefficient, and other related parameters or variables related to the heat transfer-resistance characteristics.

[0183] It should also be noted that the directional terms mentioned in the embodiments, such as "upper", "lower", "front", "back", "left", "right", etc., are only the directions of the reference drawings, and are not intended to limit the protection scope of the present application. Throughout the drawings, the same elements are represented by the same or similar reference numerals. When it may cause confusion to the understanding of the present application, the conventional structures or configurations will be omitted.

[0184] The above describes the embodiments of the present application. However, these embodiments are only for illustrative purposes, and are not intended to limit the scope of the present application. Although each embodiment is described above, this does not mean that the measures in each embodiment cannot be used advantageously in combination. The scope of the present application is defined by the appended claims and their equivalents. Without departing from the scope of the present application, those skilled in the art can make various substitutions and modifications, which should all fall within the scope of the present application.

Claims

1. A flue simulation test platform, characterized in that, The utility model relates to a heat exchange test device, comprising: a gas flow circulation mechanism (4) comprising: a pipeline defining a test flow channel inside, the test flow channel being provided with a test part (45) for detachably mounting a heat exchange pipe (5), the heat exchange pipe (5) being covered inside the pipeline in the mounting state; a simulation part provided inside the pipeline, suitable for forming a gas flow serving as a heat medium in the test flow channel and making the gas flow pass through the outside of the heat exchange pipe (5) to form different heat exchange characteristics; a medium internal circulation mechanism (2) communicating with the heat exchange pipe (5), suitable for forming a medium circulation inside the heat exchange pipe (5) so that the medium exchanges heat with the gas flow; and a detection mechanism (1) comprising a plurality of detection parts provided in the gas flow circulation mechanism (4) and the medium internal circulation mechanism (2), for collecting at least one of the temperature, air pressure and flow rate of the gas flow before and after passing through the heat exchange pipe (5) and the medium; the medium internal circulation mechanism (2) comprises a gas circulation part with a gaseous medium and a liquid circulation part with a liquid medium; the simulation part comprises: an air guide assembly mounted on the pipeline, suitable for forming a gas flow in the test flow channel; and a heating assembly (42) mounted on the pipeline, for adjusting the temperature of the gas flow so that the temperature of the gas flow entering the simulation part and / or the test part remains stable and is higher than the temperature of the medium inside the heat exchange pipe (5); the simulation part further comprises an air inlet simulation assembly (44) detachably mounted upstream of the test part (45), for adjusting the flue form and / or air distribution form upstream of the heat exchange pipe (5).

2. The test platform of claim 1, wherein, Further comprising a control mechanism in communication connection with the simulation part, the medium internal circulation mechanism (2) and the detection mechanism (1), the control mechanism being suitable for collecting the detection signals of the detection mechanism (1) to adjust at least one of the temperature of the gas flow, the flow rate of the gas flow and the flow rate of the medium.

3. The test platform of claim 1, wherein, the air guide assembly comprises: a first fan (43) provided inside the pipeline, suitable for sending air along the circulation direction of the pipeline so that the gas inside the test flow channel forms a gas flow; and a second fan (41) provided outside the pipeline and in communication with the test flow channel, suitable for sending external gas into the test flow channel to supplement the gas flow formed in the test flow channel; wherein the air sending directions of the first fan (43) and the second fan (41) are consistent with the circulation direction of the gas flow.

4. The test platform of claim 3, wherein, the heating assembly (42) is mounted between the first fan (43) and the second fan (41).

5. The test platform of claim 1, wherein, the heating assembly (42) comprises a modular electric heating resistance wire.

6. The test platform of claim 1, wherein, the air inlet simulation assembly (44) comprises a plurality of flue simulation parts, the flue simulation parts being configured in at least one of a right-angle flue structure, an inclined flue structure and a variable cross-section flue structure, and the flue simulation parts are alternatively or sequentially mounted on the pipeline.

7. The test platform of claim 1, wherein The air inlet simulation assembly (44) further comprises a plurality of air distribution simulation members configured to at least one of uniform air flow distribution structure and non-uniform air flow distribution structure, and the plurality of air distribution simulation members are alternatively or sequentially installed on the pipeline.

8. The test platform of any one of claims 1, 6, 7, wherein, The pipeline further comprises an inlet transition section (46) arranged upstream of the air inlet simulation assembly (44), and the inlet transition section (46) is configured to gradually expand the cross-sectional area of the air flow from upstream to downstream, so as to improve the ventilation of the air flow entering the air inlet simulation assembly (44).

9. The test platform of claim 8, wherein, The pipeline further comprises an outlet transition section (47) arranged downstream of the test section (45), and the outlet transition section (47) is configured to gradually reduce the cross-sectional area of the air flow from upstream to downstream, so as to improve the wind pressure of the air flow flowing out of the heat exchange pipe (5).

10. The test platform of claim 1 or 2, wherein, The gas circulation part and the liquid circulation part are in communication with the input end and the output end of the heat exchange pipe (5), and are configured to be alternatively in communication with the heat exchange pipe (5), so that the gas medium or the liquid medium forms a medium circulation in the heat exchange pipe (5).

11. The test platform of claim 1 or 2, wherein, The detection mechanism (1) comprises: a first detection part arranged at a position upstream and downstream of the heat exchange pipe (5) in the test flow channel, for detecting the temperature, wind pressure and flow rate of the air flow flowing through the heat exchange pipe (5) before flowing through the heat exchange pipe (5); and a second detection part arranged at a position upstream and downstream of the heat exchange pipe (5) in the medium internal circulation mechanism (2), for detecting the temperature, wind pressure and flow rate of the medium flowing through the heat exchange pipe (5) before flowing through the heat exchange pipe (5).

12. The test platform of claim 11, wherein, The first detection part comprises: a first front detection group (11) arranged at a position upstream of the heat exchange pipe (5) in the test flow channel, suitable for detecting the temperature, wind pressure and flow rate of the air flow before flowing through the heat exchange pipe (5); and a first rear detection group (12) arranged at a position downstream of the heat exchange pipe (5) in the test flow channel, suitable for detecting the temperature and wind pressure of the air flow after flowing through the heat exchange pipe (5).

13. The test platform of claim 11, wherein, The second detection part comprises: a second front detection group (13) arranged at a position upstream of the heat exchange pipe (5) in the medium internal circulation mechanism (2), suitable for detecting the temperature, pressure and flow rate of the medium before flowing through the heat exchange pipe (5); and a second rear detection group (14) arranged at a position downstream of the heat exchange pipe (5) in the medium internal circulation mechanism (2), suitable for detecting the temperature and wind pressure of the medium after flowing through the heat exchange pipe (5).

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