Experimental device for comprehensive heat transfer teaching

Abstract

The invention discloses an experimental device for comprehensive heat transfer teaching, which comprises a steam generator, a smooth double-pipe heat exchanger, a corrugated double-pipe heat exchanger, a tubular heat exchanger, an air cooler and a vortex air pump, one side of the top end of the steam generator is provided with a steam outlet communicated with the steam generator and a steam inlet pipeline of a shell pass inlet of the smooth double-pipe heat exchanger, the corrugated double-pipe heat exchanger and the tubular heat exchanger; the two ends of a tube pass of the tube type heat exchanger are each provided with a tube pass end socket fixedly installed through a chuck type end socket fast-installation assembly. Through cooperation of the steam generator, the smooth double-pipe heat exchanger, the corrugated double-pipe heat exchanger, the shell and tube heat exchanger, the vortex air pump, the steam air inlet pipeline, the chuck type end socket fast-assembling assembly, the tube pass end socket, the exhaust control pipeline and the tube pass air inlet header pipe, students can more visually observe the influence of the heat exchange area change on the heat transfer performance; and students can grasp the heat transfer principle more intensively.

Description

Technical Field

[0001] The present invention relates to the technical field of heat transfer experimental devices, and particularly to an experimental device for comprehensive heat transfer teaching. Background Technique

[0002] In engineering education, heat transfer is one of the core courses, and experimental teaching is a key link to help students understand the heat transfer principle. Its teaching quality directly affects students' understanding and application ability of the heat transfer principle.

[0003] Traditional double-pipe heat transfer experimental devices mainly consist of a steam generator, various double-pipe heat exchangers, a condensate storage tank, etc. Although these devices can achieve basic heat transfer experimental functions, during the experiment, they can only display the basic heat exchange phenomenon between steam and air, and students cannot deeply explore the changing law of the heat transfer process by changing key parameters such as the heat exchange area and fluid flow rate. Summary of the Invention

[0004] In order to solve the defect that in the existing technology, it is difficult to flexibly adjust the heat exchange area of a shell-and-tube heat exchanger, its heat exchanger structure is fixed, and the number and layout of the tube bundles are difficult to change, resulting in students being difficult to intuitively observe and analyze the influence of the change of the heat exchange area on the heat transfer effect, the present invention provides an experimental device for comprehensive heat transfer teaching.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: An experimental device for comprehensive heat transfer teaching of the present invention includes a steam generator, a smooth double-pipe heat exchanger, a corrugated double-pipe heat exchanger, a shell-and-tube heat exchanger, an air cooler, and a vortex air pump. One side of the top of the steam generator is provided with a steam inlet pipeline for connecting the steam outlet of the steam generator and the shell-side inlets of the smooth double-pipe heat exchanger, the corrugated double-pipe heat exchanger, and the shell-and-tube heat exchanger. Both ends of the tube side of the shell-and-tube heat exchanger are provided with tube-side tube heads fixedly installed through a chuck-type head quick-installation assembly. The air outlet of the air cooler is connected to the bottom inlet of the steam generator, and an exhaust control pipeline for connecting the air inlet of the air cooler and the non-condensable gas vent ports of the shell sides of the smooth double-pipe heat exchanger, the corrugated double-pipe heat exchanger, and the shell-and-tube heat exchanger is provided at the air inlet of the air cooler; A tube-side exhaust pipeline for connecting the tube-side outlets of the smooth double-pipe heat exchanger, the corrugated double-pipe heat exchanger, and the shell-and-tube heat exchanger is provided at the inlet of the vortex air pump, and a tube-side intake main pipeline for connecting the tube-side inlets of the smooth double-pipe heat exchanger, the corrugated double-pipe heat exchanger, and the shell-and-tube heat exchanger to the outside air is provided at the tube-side inlets of the smooth double-pipe heat exchanger, the corrugated double-pipe heat exchanger, and the shell-and-tube heat exchanger.

[0006] The beneficial effects of the present invention are: 1. This experimental device for comprehensive heat transfer teaching, through the cooperation of a steam generator, a smooth tube-sheet heat exchanger, a corrugated tube-sheet heat exchanger, a shell-and-tube heat exchanger, a vortex air pump, a steam inlet pipeline, a chuck-type head quick-assembly component, a tube-side head, an exhaust control pipeline, and a tube-side inlet main pipe, when conducting heat exchange, starts the steam generator and the vortex air pump to make the steam enter the tube-side part of the heat exchanger through the steam inlet pipeline. At the same time, air flows into the tube-side part of the heat exchanger and exchanges heat with the steam. Different heat exchangers can be tested first to compare the heat transfer performance of different heat exchangers. Also, after testing the shell-and-tube heat exchanger, the tube-side head can be quickly disassembled through the chuck-type head quick-assembly component, and then some pipelines inside the shell-and-tube heat exchanger can be blocked, thereby adjusting the tube-side heat transfer area of the shell-and-tube heat exchanger. After the adjustment is completed, the tube-side head is quickly fixed and installed on the shell-and-tube heat exchanger again through the chuck-type head quick-assembly component, and then the above heat exchange steps are repeated to compare the heat transfer effects under different heat transfer areas, so that students can more intuitively observe the influence of the change in heat transfer area on the heat transfer performance and strengthen their mastery of the heat transfer principle; 2. This experimental device for comprehensive heat transfer teaching, through the cooperation of a vortex air pump, an exhaust control pipeline, and a tube-side inlet main pipe, after the vortex air pump is started, under the negative pressure generated by the air pump, external air is sucked into the tube-side inlet main pipe. The air in the tube-side inlet main pipe continues to enter the tube-side inlets of the smooth tube-sheet heat exchanger, the corrugated tube-sheet heat exchanger, and the shell-and-tube heat exchanger under the action of negative pressure, and then enters the tube-side of the heat exchanger and conducts countercurrent heat exchange with the high-temperature steam in the shell-side, so that the air provides cold fluid air for the system in a suction ventilation manner, effectively solving the problems of unstable and gradually increasing initial air temperature during the experiment, thereby significantly improving the accuracy and reliability of the experimental data; 3. This experimental device for comprehensive heat transfer teaching, through the cooperation of a steam generator, an air cooler, and an exhaust control pipeline, the air cooler can cool the non-condensable gas, condense the steam in it and return it to the steam generator, realizing the recycling of the condensate, reducing the waste of water resources. At the same time, this design also avoids the direct discharge of steam and non-condensable gas, reducing energy consumption and environmental heat pollution, meeting the requirements of modern green laboratories; 4. This experimental device for comprehensive heat transfer teaching, through the setting of a sight glass and a lighting lamp, during the heat exchange process, the user can observe the condensation phenomenon in the shell-side part of the smooth tube-sheet heat exchanger and the corrugated tube-sheet heat exchanger through the sight glass, and the lighting lamp can provide lighting for the part corresponding to the sight glass, facilitating the user to observe when the light is insufficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. In the drawings: Figure 1 It is a schematic process flow diagram of an experimental device for comprehensive heat transfer teaching according to the present invention; Figure 2 It is a schematic three-dimensional structure diagram of the tube-side head of an experimental device for comprehensive heat transfer teaching according to the present invention; Figure 3 It is a schematic three-dimensional structure diagram of a smooth tube heat exchanger and a corrugated tube heat exchanger of an experimental device for comprehensive heat transfer teaching according to the present invention.

[0008] In the figure: 1. Steam generator; 2. Smooth tube heat exchanger; 3. Corrugated tube heat exchanger; 4. Shell and tube heat exchanger; 5. Air cooler; 6. Vortex air pump; 7. Tube-side head; 8. Tube-side inlet main pipe; 9. Steam inlet main pipe; 10. First steam inlet pipe; 11. Second steam inlet pipe; 12. Third steam inlet pipe; 13. Steam inlet control valve; 14. Steam vent main pipe; 15. First steam vent pipe; 16. Second steam vent pipe; 17. Third steam vent pipe; 18. Steam vent control valve; 19. Tube-side exhaust main pipe; 20. First tube-side exhaust pipe; 21. Second tube-side exhaust pipe; 22. Third tube-side exhaust pipe; 23. Tube-side exhaust control valve; 24. Head chuck; 25. Shell chuck; 26. Gasket; 27. Quick-release clamp; 28. Safety liquid seal; 29. First drain valve; 30. Steam outlet pressure sensor; 31. Local pressure display meter; 32. Water adding pipe; 33. Water inlet valve; 34. Steam generation temperature sensor; 35. Second drain valve; 36. First silencer; 37. Air bypass pipe; 38. Air bypass valve; 39. Second silencer; 40. First air filter; 41. First air outlet temperature sensor; 42. Second air outlet temperature sensor; 43. Third air outlet temperature sensor; 44. First steam inlet temperature sensor; 45. Second steam inlet sensor; 46. First steam outlet temperature sensor; 47. Second steam outlet sensor; 48. Venturi flowmeter; 49. Air initial pressure sensor; 50. Air initial temperature sensor; 51. Third silencer; 52. Second air filter; 53. Venturi flow differential pressure sensor; 54. First air inlet temperature sensor; 55. Second air inlet temperature sensor; 56. Third inlet temperature sensor; 57. Sight glass; 58. Lighting lamp. Specific embodiments

[0009] The following describes the preferred embodiments of the present invention with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

[0010] Embodiment: Refer to Figure 1 , Figure 2 and Figure 3, an experimental device for comprehensive heat transfer teaching according to the present invention includes a steam generator 1, a smooth tube-in-tube heat exchanger 2, a corrugated tube-in-tube heat exchanger 3, a shell-and-tube heat exchanger 4, an air cooler 5, and a vortex air pump 6. The tube passes of the smooth tube-in-tube heat exchanger 3 and the corrugated tube-in-tube heat exchanger 4 are made of copper tubes, and the tube pass of the shell-and-tube heat exchanger 5 is made of stainless steel tubes. The shell passes of the smooth tube-in-tube heat exchanger 3, the corrugated tube-in-tube heat exchanger 4, and the shell-and-tube heat exchanger 5 are all made of stainless steel shells; On the outer side walls of the smooth tube-in-tube heat exchanger 2 and the corrugated tube-in-tube heat exchanger 3, sight glasses 57 are fixedly installed through flanges. Lighting lamps 58 are installed on the sight glasses 57. A safety liquid seal 28 is further provided at the top of the steam generator 1. A first drain valve 29 is provided at the bottom of the safety liquid seal 28. A steam outlet pressure sensor 30 and a local pressure display meter 31 are provided in the steam inlet main pipe 9. A water adding pipe 32 communicating with the water inlet of the steam generator 1 is provided at the top of the steam generator 1. A water inlet valve 33 is provided on the water adding pipe 32. A steam generation temperature sensor 34 is provided in the steam generator 1. A second drain valve 35 is provided at the bottom of the steam generator 1; The user can open the water inlet valve 33 and add distilled water into the steam generator 1 through the water adding pipe 32. The steam generator 1 can heat the distilled water located inside it through an internal heating element to raise the temperature and vaporize it to generate saturated steam. At the same time, the steam generation temperature sensor 34 located inside the steam generator 1 can monitor the internal temperature of the steam generator 1 in real time. The steam outlet pressure is monitored by the steam outlet pressure sensor 30 and the local pressure display meter 31 to ensure that the steam pressure is stable within the range required for the experiment.

[0011] Refer to Figure 1 , on one side of the top of the steam generator 1, a steam inlet pipeline is provided for connecting the steam outlet of the steam generator 1 and the shell-side inlets of the smooth tube-in-tube heat exchanger 2, the corrugated tube-in-tube heat exchanger 3, and the shell-and-tube heat exchanger 4. The steam inlet pipeline includes a steam inlet main pipe 9 connected to the steam outlet of the steam generator 1, a first steam inlet pipe 10 connected between the shell-side inlet of the smooth tube-in-tube heat exchanger 2 and the steam inlet main pipe 9, a second steam inlet pipe 11 connected between the shell-side inlet of the corrugated tube-in-tube heat exchanger 3 and the steam inlet main pipe 9, and a third steam inlet pipe 12 connected between the shell-side inlet of the shell-and-tube heat exchanger 4 and the steam inlet main pipe 9. Steam inlet control valves 13 are provided on the first steam inlet pipe 10, the second steam inlet pipe 11, and the third steam inlet pipe 12; Steam is discharged from the steam outlet of the steam generator 1 and enters the main steam inlet pipe 9. The main steam inlet pipe 9 serves to collect and distribute steam. The steam continues to maintain a high temperature and high pressure state in this main pipe, and then flows into the shell-side inlets of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3, and the shell-and-tube heat exchanger 4 through the first steam inlet pipe 10, the second steam inlet pipe 11, and the third steam inlet pipe 12 respectively. At the same time, the on-off and flow rate of the first steam inlet pipe 10, the second steam inlet pipe 11, and the third steam inlet pipe 12 can be controlled through the steam inlet control valve 13. After the steam enters the shell-side parts of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3, and the shell-and-tube heat exchanger 4 through the shell-side inlets of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3, and the shell-and-tube heat exchanger 4, it conducts convective heat transfer with the air in the tube-side parts of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3, and the shell-and-tube heat exchanger 4.

[0012] Refer to Figure 3 , tube-side heads 7 are provided at both ends of the tube-side of the shell-and-tube heat exchanger 4 and are fixedly installed through the chuck-type head quick-installation assembly. The chuck-type head quick-installation assembly includes a head chuck 24 fixedly connected to one end of the tube-side head 7 close to the shell-and-tube heat exchanger 4, a shell chuck 25 fixedly connected to both ends of the outer side wall of the shell of the shell-and-tube heat exchanger 4 and adapted to the head chuck 24, a gasket 26 located between the head chuck 24 and the shell chuck 25, and a quick-installation clamp 27 for clamping the head chuck 24 and the shell chuck 25; When it is necessary to change the tube-side heat transfer area of the shell-and-tube heat exchanger 4, the quick-installation clamp 27 can be loosened, the head chuck 24 and the shell chuck 25 can be separated, the tube-side head 7 can be disassembled, and then part of the pipeline in the shell-and-tube heat exchanger 4 can be blocked, thereby adjusting the tube-side heat transfer area of the shell-and-tube heat exchanger 4. After the adjustment is completed, the head chuck 24 of the tube-side head 7 is aligned with the shell chuck 25 again, a gasket 26 is placed between the head chuck 24 and the shell chuck 25, and then the head chuck 24 and the shell chuck 25 are clamped again through the quick-installation clamp 27 to complete the fixed installation of the tube-side head 7.

[0013] Refer to Figure 1 , Figure 2 and Figure 3, the air outlet of the air cooler 5 is connected to the bottom inlet of the steam generator 1. An exhaust control pipeline is provided at the air inlet of the air cooler 5 for connecting the air inlet of the air cooler 5 and the non-condensable gas vent outlets of the shell sides of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3, and the shell and tube heat exchanger 4. The exhaust control pipeline includes a steam vent main pipe 14 connected to the air inlet of the air cooler 5, a first steam vent pipe 15 connected between the non-condensable gas vent outlet of the smooth tube heat exchanger 2 and the steam vent main pipe 14, a second steam vent pipe 16 connected between the non-condensable gas vent outlet of the corrugated tube heat exchanger 3 and the steam vent main pipe 14, and a third steam vent pipe 17 connected between the non-condensable gas vent outlet of the shell and tube heat exchanger 4 and the steam vent main pipe 14. Steam vent control valves 18 are provided on the first steam vent pipe 15, the second steam vent pipe 16, and the third steam vent pipe 17; During the heat exchange process of the steam, part of the steam condenses into liquid, but there is still a small amount of non-condensable gas. Due to the pressure difference, this part of the non-condensable gas can be discharged from the non-condensable gas vent outlets of the shell sides of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3, and the shell and tube heat exchanger 4. The non-condensable gas first enters the corresponding first steam vent pipe 15, second steam vent pipe 16, and third steam vent pipe 17. Steam vent control valves 18 are installed on each vent pipeline to control the on / off of the first steam vent pipe 15, the second steam vent pipe 16, and the third steam vent pipe 17 and the discharge rate of the non-condensable gas inside. The non-condensable gas finally converges into the steam vent main pipe 14. Inside the steam vent main pipe 14, the non-condensable gas continues to flow driven by the pressure difference and is then transported to the air cooler 5; A first steam inlet temperature sensor 44 is provided at the shell side inlet of the smooth tube heat exchanger 2, a second steam inlet sensor 45 is provided at the shell side inlet of the corrugated tube heat exchanger 3, a first steam outlet temperature sensor 46 is provided at the shell side outlet of the smooth tube heat exchanger 2, and a second steam outlet sensor 47 is provided at the shell side outlet of the corrugated tube heat exchanger 3; The first steam inlet temperature sensor 44 and the second steam inlet sensor 45 respectively detect the steam temperatures entering the shell sides of the smooth tube heat exchanger 2 and the corrugated tube heat exchanger 3, and the first steam outlet temperature sensor 46 and the second steam outlet sensor 47 monitor the steam temperatures discharged from the shell sides of these two heat exchangers.

[0014] Refer to Figure 1 、 Figure 2 and Figure 3, a tube - side exhaust pipeline for connecting the tube - side outlets of the smooth - tube heat exchanger 2, the corrugated - tube heat exchanger 3, and the shell - and - tube heat exchanger 4 is provided at the inlet of the vortex air pump 6. The tube - side exhaust pipeline includes a tube - side exhaust main pipe 19 connected to the inlet of the vortex air pump 6, a first tube - side exhaust pipe 20 connected between the tube - side outlet of the smooth - tube heat exchanger 2 and the tube - side exhaust main pipe 19, a second tube - side exhaust pipe 21 connected between the tube - side outlet of the corrugated - tube heat exchanger 3 and the tube - side exhaust main pipe 19, and a third tube - side exhaust pipe 22 connected between the tube - side outlet of the shell - and - tube heat exchanger 4 and the tube - side exhaust main pipe 19. Tube - side exhaust control valves 23 are provided on the first tube - side exhaust pipe 20, the second tube - side exhaust pipe 21, and the third tube - side exhaust pipe 22. A first air outlet temperature sensor 41 is provided in the first tube - side exhaust pipe 20, a second air outlet temperature sensor 42 is provided in the second tube - side exhaust pipe 21, and a third air outlet temperature sensor 43 is provided in the third tube - side exhaust pipe 22.

[0015] Refer to Figure 1 , a tube - side intake main pipe 8 for connecting the tube - side inlets of the smooth - tube heat exchanger 2, the corrugated - tube heat exchanger 3, and the shell - and - tube heat exchanger 4 to the outside air is provided at the tube - side inlets of the smooth - tube heat exchanger 2, the corrugated - tube heat exchanger 3, and the shell - and - tube heat exchanger 4. A first silencer 36 is installed at the outlet of the vortex air pump 6. On one side of the outer wall of the tube - side exhaust main pipe 19, an air bypass pipe 37 connected to the tube - side exhaust main pipe 19 is provided. An air bypass valve 38, a second silencer 39, and a first air filter 40 are provided on the air bypass pipe 37; At one end of the tube - side intake main pipe 8 far from the tube - side inlets of the smooth - tube heat exchanger 2, the corrugated - tube heat exchanger 3, and the shell - and - tube heat exchanger 4, a venturi flowmeter 48, an air initial pressure sensor 49, an air initial temperature sensor 50, a third silencer 51, and a second air filter 52 are provided. A venturi flow differential pressure sensor 53 is fixedly installed on the venturi flowmeter 48. A first air inlet temperature sensor 54 is provided at the tube - side inlet of the smooth - tube heat exchanger 2, a second air inlet temperature sensor 55 is provided at the tube - side inlet of the corrugated - tube heat exchanger 3, and a third inlet temperature sensor 56 is provided at the tube - side inlet of the shell - and - tube heat exchanger 4.

[0016] Refer to Figure 1 、 Figure 2 and Figure 3, after the vortex air pump 6 starts, under the negative pressure generated by the air pump, outside air is sucked into the intake main pipe 8 of the tube side. The air first passes through the third silencer 51. The third silencer 51 reduces the noise generated by air flow through the internal sound-absorbing material and special structural design, reducing the interference to the experimental environment. Then, the air flows through the second air filter 52. The second air filter 52 is filled with multiple layers of filtering media, such as filter screens, activated carbon, etc., which can effectively filter dust, impurities and fine particles in the air, preventing these pollutants from entering the heat exchanger and affecting the heat transfer effect or damaging the equipment. The air after silencing and filtering continues to flow and successively passes through the Venturi flowmeter 48, the air initial pressure sensor 49 and the air initial temperature sensor 50. The Venturi flowmeter 48 measures the air flow rate passing through it. The air initial pressure sensor 49 and the air initial temperature sensor 50 can respectively monitor the initial pressure and temperature of the air when it enters the system; Before the outside air enters the tube side of the heat exchanger, the first air inlet temperature sensor 54, the second air inlet temperature sensor 55 and the third inlet temperature sensor 56 can respectively measure the initial temperature of the air entering the tube sides of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3 and the shell-and-tube heat exchanger 4; The air in the intake main pipe 8 of the tube side continues to enter the tube side inlets of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3 and the shell-and-tube heat exchanger 4 under the action of negative pressure, and then enters the tube side of the heat exchanger and exchanges heat countercurrently with the high-temperature steam in the shell side; During the process of the air flowing through the tube side, the first air outlet temperature sensor 41, the second air outlet temperature sensor 42 and the third air outlet temperature sensor 43 respectively and real-time monitor the air temperature flowing out from the tube side outlets of each heat exchanger, and thus can calculate and evaluate the heat absorbed by the air in each heat exchanger and the heat transfer performance of the heat exchanger; During the heat exchange process, the user can observe the condensation phenomenon in the shell side parts of the smooth tube heat exchanger 2 and the corrugated tube heat exchanger 3 through the sight glass 57. The lighting lamp 58 can provide lighting effect for the part corresponding to the sight glass 57, facilitating the user to observe when the light is insufficient; After the non-condensable gas enters the air cooler 5, the air cooler 5 starts the fan to make the outside cold air and the non-condensable gas conduct forced convection heat exchange. Inside the air cooler 5, the steam in the non-condensable gas gradually condenses into liquid when it meets cold. The condensate flows downward under the action of gravity, is discharged through the air outlet of the air cooler 5, and flows back to the bottom inlet of the steam generator 1. During this process, a small amount of uncondensed gas is discharged into the atmosphere through the exhaust port of the air cooler 5. The recovered condensate re-enters the steam generator 1, realizing the recycling of water resources, and at the same time also helps to maintain the liquid level stability in the steam generator, ensuring the continuous and stable steam generation process.

[0017] All the electrical components mentioned in this article are electrically connected to a control system (not shown in the figure), and the control system is a touch all-in-one machine.

[0018] The working principle of the present invention is as follows: During use, first check the steam generator 1, smooth tube heat exchanger 2, corrugated tube heat exchanger 3, shell and tube heat exchanger 4, air cooler 5, vortex air pump 6 and all connecting pipelines, valves, sensors and other components to ensure no damage and tight connection. Then check the water level inside the steam generator 1. If the water level is lower than 50%, it is necessary to open the water inlet valve 33 and add water through the water supply pipe 32 until the water level reaches 50%-80% of the water level gauge scale. Connect the power supply of the device and turn on the control system (not shown in the figure). Start the heating element of the steam generator 1 in the control system to start heating the water inside. The steam generation temperature sensor 34 monitors the water temperature in real time and feeds the temperature signal back to the control system. When the water temperature reaches the set temperature, a large amount of water vaporizes into steam, and the pressure inside the steam generator gradually increases. The steam outlet pressure sensor 30 monitors the steam pressure, and the local pressure display meter 31 displays the pressure value in real time. The generated steam is discharged from the steam outlet at the top of the steam generator 1 and enters the steam inlet main pipe 9. The control system controls the on-off and opening degree of the steam inlet control valve 13 according to the experimental requirements, so that the steam passes through the first steam inlet pipe 10, the second steam inlet pipe 11 and the third steam inlet pipe 12 and enters the shell side inlets of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3 and the shell and tube heat exchanger 4 respectively. For example, when it is necessary to study the heat transfer performance of the smooth tube heat exchanger 2 under different steam flow rates, the steam inlet control valve 13 on the first steam inlet pipe 10 can be opened separately to make the steam completely flow into the smooth tube heat exchanger 2 through the first steam inlet pipe 10. Start the vortex air pump 6. Under its pumping action, the outside air enters the tube side inlet main pipe 8 through the tube side inlet main pipe 8. Inside the tube side inlet main pipe 8, the air passes through the third muffler 51 to reduce noise and the second air filter 52 to filter dust and impurities in turn, and then flows through the venturi flowmeter 48. The venturi flow differential pressure sensor 53 monitors the air flow rate, and at the same time the air initial pressure sensor 49 and the air initial temperature sensor 50 monitor the air initial pressure and temperature. The pretreated air is split from the tube side inlet main pipe 8 and enters the tube side inlets of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3 and the shell and tube heat exchanger 4 respectively. At the tube side inlets of each heat exchanger, the first air inlet temperature sensor 54, the second air inlet temperature sensor 55 and the third inlet temperature sensor 56 measure the air temperature entering the tube side and transmit it to the control system. Inside the tube side, the air and the steam in the shell side perform countercurrent heat exchange. Taking the smooth tube heat exchanger 2 as an example, the steam in the shell side transfers heat to the air flowing in the tube side through the tube wall. The temperature of the air gradually increases. The first air outlet temperature sensor 41 monitors the air outlet temperature in real time at the tube side outlet and feeds the data back to the control system for calculating parameters such as the heat transfer amount and heat transfer coefficient of the heat exchanger; For the shell and tube heat exchanger 4, if it is necessary to study the influence of the heat transfer area on heat transfer, the quick-release clamp 27 can be loosened, the head chuck 24 and the shell chuck 25 can be separated, the tube side head 7 can be disassembled, and then part of the pipeline in the shell and tube heat exchanger 4 can be blocked. Furthermore, the heat transfer area of the tubes in the shell and tube heat exchanger 4 can be adjusted. After the adjustment is completed, the head chuck 24 of the tube side head 7 is aligned with the shell chuck 25 again, and a gasket 26 is placed between the head chuck 24 and the shell chuck 25. Then, the head chuck 24 and the shell chuck 25 are clamped again through the quick-release clamp 27 to complete the fixed installation of the tube side head 7. Then, the above air circulation and heat transfer process is carried out to compare the heat transfer effects under different heat transfer areas; During the heat exchange process between the steam in the shell side and the tube side air of the heat exchanger, part of the steam condenses, and the uncondensed non-condensable gas is discharged from the shell side non-condensable gas vent of the smooth tube heat exchanger 2, the corrugated tube heat exchanger 3, and the shell and tube heat exchanger 4 respectively; The non-condensable gas enters the first steam vent pipe 15, the second steam vent pipe 16, and the third steam vent pipe 17 in sequence. The steam vent control valves 18 on each pipeline adjust the opening according to the control system instructions to control the non-condensable gas discharge rate, and the non-condensable gas finally converges into the steam vent main pipe 14; The non-condensable gas converging into the steam vent main pipe 14 enters the air cooler 5. The air cooler 5 starts the fan to make the outside cold air and the non-condensable gas conduct forced convection heat transfer. The steam in the non-condensable gas gradually condenses into liquid. Under the action of gravity, the condensate flows back to the bottom inlet of the steam generator 1 through the air outlet of the air cooler 5 to realize condensate recovery, and a small amount of uncondensed gas is discharged into the atmosphere through the exhaust port of the air cooler 5; After the experiment is completed, first turn off the heating element of the steam generator 1 to stop steam generation. After the pressure in the steam generator drops to near atmospheric pressure, close the steam inlet control valve 13. Then, turn off the vortex air pump 6 to stop air circulation, and then close the tube side exhaust control valve 23; Open the second drain valve 35 at the bottom of the steam generator 1 to drain the remaining water in the steam generator. At the same time, open the first drain valve 29 at the bottom of the safety liquid seal 28 to drain the water in the safety liquid seal. For the condensate that may remain in each heat exchanger and the connecting pipeline, it can be drained by opening the corresponding drain valve if any; Export various types of data recorded during the experiment from the control system, such as temperature, pressure, flow rate, etc., for subsequent experimental analysis. Clean the device, remove dust and impurities on the surfaces of each component, check whether each component is damaged or abnormal, and replace or repair the damaged components in a timely manner to prepare for the next experiment.

[0019] Adjust the bypass valve 43 of the vortex air pump to be fully open, open the stop valve 35 for the inlet of smooth tube steam and the stop valve 36 for the outlet of smooth tube steam, and keep other valves closed.

[0020] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A comprehensive heat transfer teaching experimental device, comprising a steam generator (1), a smooth shell-and-tube heat exchanger (2), a corrugated shell-and-tube heat exchanger (3), a shell-and-tube heat exchanger (4), an air cooler (5) and a vortex air pump (6), characterized in that: A steam air inlet pipeline for connecting the steam outlet of the steam generator (1) and the shell-side inlet of the smooth shell-and-tube heat exchanger (2), the corrugated shell-and-tube heat exchanger (3), and the shell-and-tube heat exchanger (4) is provided on one side of the top of the steam generator (1); both ends of the tube side of the shell-and-tube heat exchanger (4) are provided with tube side seals (7) fixedly installed by means of a chuck-type seal quick-install assembly; the air outlet of the air cooler (5) is connected to the bottom inlet of the steam generator (1); an exhaust control pipeline for connecting the air inlet of the air cooler (5) and the shell-side non-condensable gas vent of the smooth shell-and-tube heat exchanger (2), the corrugated shell-and-tube heat exchanger (3), and the shell-and-tube heat exchanger (4) is provided at the air inlet of the air cooler (5); The inlet of the vortex air pump (6) is provided with a tube-side exhaust pipeline for communicating with the tube-side outlets of the smooth shell-and-tube heat exchanger (2), the corrugated shell-and-tube heat exchanger (3), and the shell-and-tube heat exchanger (4); the tube-side inlet of the smooth shell-and-tube heat exchanger (2), the corrugated shell-and-tube heat exchanger (3), and the shell-and-tube heat exchanger (4) is provided with a tube-side air intake main pipe (8) communicating between the tube-side inlet of the smooth shell-and-tube heat exchanger (2), the corrugated shell-and-tube heat exchanger (3), and the shell-and-tube heat exchanger (4) and the outside air.

2. A comprehensive heat transfer teaching experimental device according to claim 1, characterized in that: The steam intake pipeline comprises a steam intake main pipe (9) connected to the steam outlet of the steam generator (1), a first steam intake pipe (10) connected between the shell inlet of the smooth shell-and-tube heat exchanger (2) and the steam intake main pipe (9), a second steam intake pipe (11) connected between the shell inlet of the corrugated shell-and-tube heat exchanger (3) and the steam intake main pipe (9), and a third steam intake pipe (12) connected between the shell inlet of the shell-and-tube heat exchanger (4) and the steam intake main pipe (9), wherein the first steam intake pipe (10), the second steam intake pipe (11) and the third steam intake pipe (12) are all provided with steam intake control valves (13).

3. The comprehensive heat transfer teaching experimental device according to claim 1, characterized in that: The exhaust control pipeline comprises a steam vent main pipe (14) connected to the air inlet of the air cooler (5), a first steam vent pipe (15) connected between the non-condensable gas vent port of the smooth shell-and-tube heat exchanger (2) and the steam vent main pipe (14), a second steam vent pipe (16) connected between the non-condensable gas vent port of the corrugated shell-and-tube heat exchanger (3) and the steam vent main pipe (14), and a third steam vent pipe (17) connected between the non-condensable gas vent port of the shell-and-tube heat exchanger (4) and the steam vent main pipe (14), wherein the first steam vent pipe (15), the second steam vent pipe (16) and the third steam vent pipe (17) are all provided with steam vent control valves (18).

4. The comprehensive heat transfer teaching experimental device according to claim 1, characterized in that: The tube-side exhaust pipeline comprises a tube-side exhaust main pipe (19) connected to the inlet of the vortex air pump (6), a first tube-side exhaust pipe (20) connected between the tube-side outlet of the smooth shell-and-tube heat exchanger (2) and the tube-side exhaust main pipe (19), a second tube-side exhaust pipe (21) connected between the tube-side outlet of the corrugated shell-and-tube heat exchanger (3) and the tube-side exhaust main pipe (19), and a third tube-side exhaust pipe (22) connected between the tube-side outlet of the shell-and-tube heat exchanger (4) and the tube-side exhaust main pipe (19), wherein the first tube-side exhaust pipe (20), the second tube-side exhaust pipe (21) and the third tube-side exhaust pipe (22) are all provided with tube-side exhaust control valves (23).

5. The comprehensive heat transfer teaching experimental device according to claim 1, characterized in that: The chuck-type head quick-install assembly comprises a head chuck (24) fixedly connected to one end of a tube-side head (7) close to the shell-and-tube heat exchanger (4), a shell chuck (25) fixedly connected to both ends of the outer shell wall of the shell of the shell-and-tube heat exchanger (4) and adapted to the head chuck (24), a gasket (26) located between the head chuck (24) and the shell chuck (25), and a quick-install clamp (27) for clamping the head chuck (24) and the shell chuck (25).

6. The comprehensive heat transfer teaching experimental device according to claim 1, characterized in that: The steam generator (1) is also provided with a safety liquid seal (28) at the top, a first drain valve (29) is provided at the bottom of the safety liquid seal (28), a steam outlet pressure sensor (30) and a local pressure display gauge (31) are provided in the steam intake main pipe (9), a water supply pipe (32) connected to the water inlet of the steam generator (1) is provided at the top of the steam generator (1), a water supply valve (33) is provided on the water supply pipe (32), a steam generation temperature sensor (34) is provided in the steam generator (1), and a second drain valve (35) is provided at the bottom of the steam generator (1).

7. The comprehensive heat transfer teaching experimental device according to claim 1, characterized in that: A first muffler (36) is installed at the outlet of the vortex air pump (6); an air bypass pipe (37) connected to the pipe-side exhaust main pipe (19) is provided on one side of the outer wall of the pipe-side exhaust main pipe (19); and an air bypass valve (38), a second muffler (39) and a first air filter (40) are provided on the air bypass pipe (37).

8. The comprehensive heat transfer teaching experimental device according to claim 4, characterized in that: A first air outlet temperature sensor (41) is arranged in the first tube-side exhaust pipe (20), a second air outlet temperature sensor (42) is arranged in the second tube-side exhaust pipe (21), a third air outlet temperature sensor (43) is arranged in the third tube-side exhaust pipe (22), a first steam inlet temperature sensor (44) is arranged at the shell-side inlet of the smooth shell-and-tube heat exchanger (2), a second steam inlet temperature sensor (45) is arranged at the shell-side inlet of the corrugated shell-and-tube heat exchanger (3), a first steam outlet temperature sensor (46) is arranged at the shell-side outlet of the smooth shell-and-tube heat exchanger (2), and a second steam outlet temperature sensor (47) is arranged at the shell-side outlet of the corrugated shell-and-tube heat exchanger (3).

9. The comprehensive heat transfer teaching experimental device according to claim 1, characterized in that: A venturi flowmeter (48), an initial air pressure sensor (49), an initial air temperature sensor (50), a third silencer (51) and a second air filter (52) are provided at one end of the tube-side air intake main pipe (8) away from the tube-side inlet of the smooth shell-and-tube heat exchanger (2), the corrugated shell-and-tube heat exchanger (3) and the shell-and-tube heat exchanger (4); a venturi flow differential pressure sensor (53) is fixedly mounted on the venturi flowmeter (48); a first air inlet temperature sensor (54) is provided at the tube-side inlet of the smooth shell-and-tube heat exchanger (2); a second air inlet temperature sensor (55) is provided at the tube-side inlet of the corrugated shell-and-tube heat exchanger (3); and a third inlet temperature sensor (56) is provided at the tube-side inlet of the shell-and-tube heat exchanger (4).

10. The comprehensive heat transfer teaching experimental device according to claim 1, characterized in that: The outer side walls of the smooth shell-and-tube heat exchanger (2) and the corrugated shell-and-tube heat exchanger (3) are both fixedly mounted with a sight glass (57) via a flange, and a lighting lamp (58) is mounted on the sight glass (57).

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