CN108802090A - A kind of microchannel nano-fluid enhanced heat exchange experiment test device - Google Patents

Abstract

The invention discloses a microchannel nanofluid enhanced heat transfer test device, which includes a liquid storage tank, a coil heater, a fluid supply control group, a microchannel box group, DC power supply, data measurement and analysis group and liquid collection tank. For different microchannel heat exchange modules of the microchannel box group, the microchannel heat exchange module to be tested can be installed between the two ribs of the upper cover plate and the two ribs of the lower bottom plate in advance, and then the front side plate of the microchannel box group, The rear side plate, the left side plate and the right side plate constitute a microchannel box group, which reduces the inconvenience of assembling microstructures in a small space and the system error caused by assembly.

Description

A microchannel nanofluid enhanced heat transfer test device

technical field

The invention relates to a testing device. Specifically, it is a microchannel nanofluid enhanced heat exchange test device.

Background technique

In recent years, with the advancement of science and technology, the fields of electronics and machinery are developing in the direction of miniaturization and miniaturization. It is necessary to consider the effects of miniaturization of the heat and mass transfer process, and the complexity of the structure and conditions. The research of microchannels Development has become a hot topic today. The influence of nanofluids on the heat transfer of microchannels and the influence of microchannel structures on their heat transfer effects have gradually attracted people's attention and attention.

At present, the effects of different nanofluids on the heat transfer efficiency and heat transfer capacity of different microchannel structures and sizes have been extensively studied. However, due to the small size of the microchannel, many connection devices for mass transfer, temperature control, flow control, detection and analysis are required. The research on the flow rate, temperature, concentration and other parameters of the fluid requires repeated disassembly and assembly of mass transfer, temperature control, flow control, detection and analysis devices, which brings inconvenience to the operation of the experimenters and increases the uncertainties of the experimental conditions. There are large errors in the research results, which seriously affect the repeatability and consistency of the test results.

In previous experiments, the microchannel test was prepared by etching and pressing adhesion to form a single, small, integrated microchannel assembly (with other complex connections and sealing structures), which can only be used for one microchannel. Experimental verification of different test conditions for channel structures. If it is necessary to repeatedly measure or replace the core microchannel module, it needs a high cost.

Contents of the invention

Therefore, the technical problem to be solved by the present invention is to provide a microchannel nanofluid enhanced thermal test detection device.

In order to solve the above technical problems, the present invention provides the following technical solutions:

A microchannel nanofluid enhanced heat transfer test device, the microchannel nanofluid enhanced heat transfer test device includes a liquid storage tank, a coil heater, a fluid supply control group, a microchannel box group, a DC power supply, a data The measurement and analysis group and the liquid collection tank; the coil heater is located in the liquid storage tank, the liquid storage tank, the fluid supply control group, the microchannel box group and the liquid collection tank The fluid conduction between them in turn; the DC power supply is electrically connected to the microchannel box group; the data measurement and analysis group includes an optical data collector, a data collector, a synchronizer, a water pressure and temperature measuring element and a data analyzer, The water pressure and temperature measuring element includes an inlet temperature sensor, an inlet water pressure sensor, an outlet temperature sensor, an outlet water pressure sensor, and a flow meter for measuring the flow of fluid flowing through the fluid supply control group, and the inlet temperature sensor The output end, the output end of the inlet water pressure sensor, the output end of the outlet temperature sensor, the output end of the outlet water pressure sensor and the output end of the flowmeter are respectively connected to the input end of the data acquisition instrument ; The inlet temperature sensor and the inlet water pressure sensor are located at the inlet end of the microchannel box group, and the outlet temperature sensor and the outlet water pressure sensor are located at the outlet end of the microchannel box group; the optical data collection The instrument comprises a microscope, a video camera and an infrared thermal imager, the video camera is installed on the microscope, and the microscope and the infrared thermal imager are respectively located at the front and rear of the microchannel box group; the video camera The time signal output end of the infrared thermal imager, the time signal output end of the infrared thermal imager, and the data output end of the data acquisition instrument are respectively connected to the input end of the synchronizer, and the image signal output end of the camera, the The image signal output end of the infrared thermal imager and the data output end of the synchronizer are respectively connected to the input end of the data analyzer.

In the microchannel nanofluid enhanced heat transfer test device described above, the fluid supply control group includes a water pump, a first filter, a regulating valve, and a second filter, and the water pump, the first filter, and the regulating valve and the second filter in sequence; the flow meter is arranged on the pipeline between the first filter and the regulating valve, and is connected to the outlet port of the first filter and the regulating valve The inlet end of the valve is in fluid communication; the outlet end of the liquid storage tank is in fluid communication with the inlet end of the water pump; the outlet end of the second filter is in fluid communication with the inlet end of the microchannel box set.

The above-mentioned microchannel nanofluid enhanced heat exchange test test device, the microchannel box group includes an upper cover plate, a lower bottom plate, a left side plate, a right side plate, a front side plate and a rear side plate; the left side plate and the The right side plate is fixedly bonded to the left and right sides of the lower bottom plate respectively, the front side plate and the rear side plate are respectively fixed and bonded to the front side and the rear side of the lower bottom plate, and the upper cover plate is located at the upper end surfaces of the left side panel, the right side panel, the front side panel and the rear side panel, and detachably connect the left side panel, the right side panel, the front side panel and the Describe the upper end surface of the rear side panel.

In the above-mentioned microchannel nanofluid enhanced heat transfer test device, the lower bottom of the upper cover plate has a left upper rib and a right upper rib; the upper surface of the lower bottom plate has a left lower rib and a right lower rib, and the left upper The rib is located directly above the lower left rib, and the upper right rib is located directly above the lower right rib; the upper left rib and the upper right rib have an inverted concave structure, and the lower left rib and the right upper rib The lower rib has an upward convex structure, the concave-convex structure of the left upper rib is in concave-convex cooperation with the upper convex structure of the left lower rib, and the concave-convex structure of the right upper rib is aligned with the concave-convex structure of the left upper rib. The concave-convex cooperation of the upper convex structure of the lower right rib forms respectively the left fixed gap of the microchannel structure and the right fixed gap of the microchannel structure with a height of 1-2 mm.

In the above-mentioned microchannel nanofluid enhanced heat transfer test device, the left side of the upper cover plate, the left side of the lower bottom plate, the left side plate, the left side of the front side plate, and the rear side plate A first cavity is formed between the left side, the upper left rib and the lower left rib; the upper cover plate, the lower bottom plate, the upper left rib, the upper right rib, and the lower left rib A second cavity is formed between the lower right rib and the right side of the upper cover plate, the right side of the lower bottom plate, the right side of the front side plate, and the right side of the rear side plate , the upper right rib, the lower right rib and the right side plate enclose a third cavity; the outlet end of the second filter, the first cavity, the second cavity The body, the third cavity and the liquid collection tank are in fluid communication in turn; the first cavity and the third cavity are provided with spoilers; the first cavity and the second cavity The bodies are in fluid communication through the left fixed slit of the microchannel structure; the second cavity and the third cavity are in fluid communication through the right fixed slit of the microchannel structure.

The above-mentioned microchannel nanofluid enhanced heat transfer test device, the plate surface of the left side plate is provided with a circular cross-section inlet of the microchannel box group, the circular cross-section inlet is a threaded hole, and the nominal diameter of the threaded hole is M8, the circular cross-section outlet of the microchannel box group is provided on the plate of the right side plate, the circular cross-section outlet is a threaded hole, and the nominal diameter of the threaded hole is M8, the second filter The outlet end is in fluid communication with the first cavity through the circular cross-section inlet on the left side plate, and the circular cross-section outlet on the right side plate is in fluid communication with the liquid collection; A threaded hole is opened on the surface of the front side plate facing the first cavity, and the inlet water pressure sensor is fitted with the internal thread of the threaded hole. The nominal diameter of the threaded hole is M12. A threaded hole is opened on the plate facing the third cavity, and the outlet water pressure sensor is installed in the threaded hole, the nominal diameter of the threaded hole is M12; the front side plate is facing the second cavity There is an installation gap on the plate surface of the body; a threaded hole is opened on the plate surface of the rear side plate facing the first cavity, and the inlet temperature sensor is installed with the internal thread of the threaded hole. The nominal diameter of the threaded hole is M12, a threaded hole is opened on the surface of the rear side plate facing the third cavity, and the outlet temperature sensor is installed with the internal thread of the threaded hole, and the nominal diameter of the threaded hole is M12; There are 4 threaded holes on the surface of the upper cover facing the second cavity, and the nominal diameter of the threaded holes is M12; 4 holes are opened on the surface of the lower base facing the second cavity. A threaded hole, the nominal diameter of the threaded hole is M12.

The above-mentioned microchannel nanofluid enhanced heat transfer test device, the length of the upper cover plate is 136mm, and the width is 40mm; the thickness of the upper cover plate surface at the top of the first cavity, the third cavity The thickness of the upper cover plate at the top, the thickness of the lower base plate at the bottom of the first cavity, the thickness of the lower base plate at the bottom of the third cavity, the thickness of the front side plate thickness, the thickness of the rear side plate, the thickness of the left side plate and the thickness of the right side plate) are all 8mm, the thickness of the upper cover plate at the top of the second cavity and The thickness of the lower bottom plate at the bottom of the second cavity is 6mm; the thickness of the upper left rib and the upper right rib is 8mm, and the left side of the upper left rib and the upper cover plate The distance between the left side of the upper left rib is 40mm, the distance between the right side of the upper left rib and the left side of the upper right rib is 40mm, the right side of the upper right rib and the right end of the upper cover plate The distance is 40mm; the width of the inverted concave structure and the upper convex structure is 20mm, the depth of the inverted concave structure is 6mm; the length of the lower bottom plate is 120mm, and the width is 40mm. The rib thickness of the lower left rib and the lower right rib is 8 mm, the distance between the left side of the lower left rib and the left end face of the lower bottom plate is 32 mm, and the right side of the lower left rib and the The distance between the left side of the lower right rib is 40mm, and the distance between the right side of the lower right rib and the right end of the lower bottom plate is 32mm; the height of the left side plate and the right side plate is 30mm, The width of the left side plate and the right side plate is 40mm, the distance between the center of the circular cross-section inlet and the bottom surface of the left side plate and the distance between the center of the circle cross-section outlet and the bottom surface of the right side plate The distances are all 19mm, the center of the circular cross-section inlet is located at the transverse center of the left side plate, the circle center of the circular cross-section outlet is located at the transverse center of the right plate, the front side plate and The length of the rear side plate is 136mm, and the width is 38mm; the distance between the threaded hole circle center and the lower end surface of the front side plate is 19mm when installing the inlet water pressure sensor (13) and the outlet water pressure sensor. The distance between the center of the threaded hole of the inlet temperature sensor and the outlet temperature sensor and the lower end surface of the rear side plate is 19 mm, and the center of the threaded hole for installing the inlet water pressure sensor is 19 mm from the left end surface of the front side plate. The distance between the center of the threaded hole for installing the outlet water pressure sensor and the right end face of the front side plate is 23 mm, and the distance between the center of the threaded hole for installing the inlet temperature sensor and the left end face of the rear side plate is 23 mm. The distance is 23 mm, and the distance between the center of the threaded hole where the outlet temperature sensor is installed and the right end face of the rear side plate is 23 mm.

In the above-mentioned microchannel nanofluid enhanced heat transfer test device, a microchannel heat exchange module is installed in the second cavity, and the fluid inlet end of the microchannel heat exchange module is located in the left fixed gap of the microchannel structure , the fluid inlet end of the microchannel heat exchange module is located in the right fixed gap of the microchannel structure; the microchannel heat exchange module includes a constant wall temperature microchannel heat exchange module and a constant heat flow microchannel heat exchange module.

In the above-mentioned microchannel nanofluid enhanced heat transfer test device, the constant wall temperature microchannel heat exchange module includes a microchannel structure and a condensate head, the condensate head is located on the upper surface of the microchannel structure, and the microchannel The left end of the structure is tightly fitted in the left fixed gap of the microchannel structure, and the right end of the microchannel structure is tightly fitted in the right fixed gap of the microchannel structure.

The above-mentioned microchannel nanofluid enhanced heat transfer test test device, the constant heat flow microchannel heat exchange module includes a microchannel structure, an electrothermal film and a plastic heat insulation board, the electrothermal film is located on the upper surface of the microchannel structure, and the plastic The heat shield is located on the upper surface of the electrothermal film; the left end of the microchannel structure is tightly fitted in the left fixed gap of the microchannel structure, and the right end of the microchannel structure is tightly fitted in the right side of the microchannel structure. In the fixed gap; the current output end and the current input end of the electrothermal film are respectively connected to the input end and the output end of the DC power supply; the lower bottom plate is located on the left side plate, the right side plate, and the front side plate and the rear side panel, and the lower surface of the lower bottom panel, the lower end surface of the left side panel, the lower end surface of the right side panel, the lower end surface of the front side panel and the lower end surface of the rear side panel The four sides of the lower bottom plate are liquid-tightly bonded to the inner side surfaces of the left side plate, the right side plate, the front side plate and the rear side plate, and the upper cover plate clamped between the front side plate and the inner side plate of the rear side plate, and the left end of the upper cover plate is pressed against the upper end surface of the left side plate, and the right end of the upper cover plate is pressed Close on the upper end surface of the right side plate; the width of the left upper rib, the right upper rib, the left lower rib and the right lower rib is 40mm, and the left upper rib, the The upper right rib, the lower left rib and the lower right rib are all clamped between the inner side panels of the front side panel and the rear side panel.

Beneficial effect

1. For different microchannel heat exchange modules of the microchannel box group, the microchannel heat exchange module to be tested can be installed between the two ribs of the upper cover plate and the two ribs of the lower bottom plate in advance, and then assembled on the front side of the microchannel box group Plate, rear side plate, left side plate and right side plate constitute a microchannel box group, which reduces the inconvenience of assembling microstructures in a small space and the system error caused by assembly. During the test, the heat transfer coefficient h was tested. Error analysis, its error is lower than 8.37%.

2. There are grooves on the front side plate of the micro-channel box group, and there are multiple threaded holes on the upper cover and the lower bottom plate. Through the grooves and multiple threaded holes, the micro-channel heat exchange module can be realized during the test. It does not need to disassemble the entire micro-channel box group, which is easy to operate, and also reduces the influence of the systematic error of the micro-channel box group caused by the disassembly process on the test results.

3. By changing the size and structure of the ribs on the upper cover of the microchannel box group, the matching gap between the upper cover and the lower bottom plate fins can be changed, so as to match the heat exchange of microchannels of different sizes and different heat transfer methods module.

4. The microchannel nanofluid enhanced heat transfer test device of the present invention is detachable, replaceable and adjustable microchannel structure, can be applied to two test modes of constant wall temperature and constant heat flow, and can be applied to the measurement of different microchannel structures, reducing the The cost of experiment; Compared with the traditional integrated microchannel assembly, the present invention can reduce the cost of making and measuring each microchannel structure test assembly from more than 500 yuan to less than 100 yuan (not including the cost of the microchannel structure itself. price).

Description of drawings

Fig. 1 structural representation of the microchannel nanofluid enhanced heat transfer test device of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Fig. 2 is a schematic structural diagram of the front view of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Fig. 3 is a schematic structural diagram of the top view of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Fig. 4 is a schematic structural diagram of the side view of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Fig. 5 is a schematic diagram of the structure of the side view of the upper cover of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Fig. 6 is a schematic structural diagram of the side view of the bottom plate of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Fig. 7 is a schematic structural diagram of the constant wall temperature microchannel heat exchange module of the microchannel nanofluid enhanced heat exchange test device of the present invention;

Fig. 8 is a schematic structural diagram of the constant heat flow microchannel heat exchange module of the microchannel nanofluid enhanced heat exchange test device of the present invention;

Fig. 9 is a schematic diagram of the structure of the front side plate of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Figure 10 is a schematic diagram of the structure of the rear side plate of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Fig. 11 is a schematic diagram of the structure of the left panel of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Figure 12 is a schematic diagram of the structure of the upper cover plate of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Fig. 13 is a schematic diagram of the structure of the bottom plate of the microchannel box group of the microchannel nanofluid enhanced heat transfer test device of the present invention;

Fig. 14 influence diagram of different transverse wall temperatures on heat transfer Q and heat transfer coefficient h of the microchannel nanofluid enhanced heat transfer test method of the present invention;

Fig. 15 influence diagram of different transverse heat flow on the heat transfer heat Q and the heat transfer coefficient h of the microchannel nanofluid enhanced heat transfer test method of the present invention;

Fig. 16 Influence figure of nanofluid different inlet velocity on heat transfer quantity Q and heat transfer coefficient h of microchannel nanofluid enhanced heat transfer test test method of the present invention;

Fig. 17 Influence figure of different Reynolds numbers of nanofluids on heat transfer Q and heat transfer coefficient h of microchannel nanofluid enhanced heat transfer test test method of the present invention;

Fig. 18 Influence diagram of different nanofluids on the heat transfer heat Q and heat transfer coefficient h of the microchannel nanofluid enhanced heat transfer test method of the present invention;

Fig. 19 Influence diagram of different concentrations of nanofluids on heat transfer Q and heat transfer coefficient h of the microchannel nanofluid enhanced heat transfer test method of the present invention;

Fig. 20 is the figure of influence of the number of microchannels on heat transfer Q and heat transfer coefficient h of the microchannel nanofluid enhanced heat transfer test method of the present invention;

Fig. 21 Influence diagram of the microchannel pipe diameter of the microchannel nanofluid enhanced heat transfer test method of the present invention on the heat transfer quantity Q and the heat transfer coefficient h;

The reference signs in the figure represent:

1: Liquid storage tank, 2: Coil heater, 3: Micro channel box group, 4: DC power supply, 5: Liquid collection tank, 6 Data acquisition instrument, 7: Data analyzer, 8: Water pump, 9: No. One filter, 10: regulating valve, 11: second filter, 12: inlet temperature sensor, 13: inlet water pressure sensor, 14: outlet temperature sensor, 15: outlet water pressure sensor, 16: flow meter, 17: camera Instrument, 18: Infrared Thermal Imager, 19: Microscope, 20: Synchronizer, 3-1: Upper Cover, 3-2: Lower Bottom, 3-3: Left Side, 3-4: Right Side, 3 -5: Front side panel, 3-6: Rear side panel, 3-7: Left upper rib, 3-8: Right upper rib, 3-9: Left lower rib, 3-10: Right lower rib, 3- 11: Micro-channel heat exchange module, 3-12: Micro-channel structure; 3-13: Condensation head, 3-14: Electrothermal film, 3-15: Plastic insulation board; 3-A: First cavity, 3- B: second cavity, 3-C: third cavity; 3-16: left fixed gap of microchannel structure, 3-17: right fixed gap of microchannel structure, 3-18: installation gap, 3-19: inverted Concave structure, 3-20: Convex structure.

Detailed ways

As shown in Fig. 1 and Fig. 3, described a kind of microchannel nanofluid enhanced heat transfer test test device, described microchannel nanofluid enhanced heat transfer test test device comprises liquid storage tank 1, coil heater 2, Fluid supply control group, microchannel box group 3, DC power supply 4, data measurement and analysis group and liquid collection tank 5; the coil heater 2 is located in the liquid storage tank 1, and the liquid storage tank 1, The fluid supply control group, the microchannel box group 3 and the liquid collection tank 5 are in sequential fluid communication; the DC power supply 4 is electrically connected to the microchannel box group 3; the data measurement and analysis group Including optical data collector, data collector 6, synchronizer 19, water pressure and temperature measuring element and data analyzer 7, said water pressure and temperature measuring element includes inlet temperature sensor 12, inlet water pressure sensor 13, outlet temperature sensor 14. The outlet water pressure sensor 15 and the flowmeter 16 used to measure the flow of fluid flowing through the fluid supply control group, the output end of the inlet temperature sensor 12, the output end of the inlet water pressure sensor 13, the outlet The output end of the temperature sensor 14, the output end of the outlet water pressure sensor 15 and the output end of the flow meter 16 are respectively connected with the input end of the data acquisition instrument 6; the inlet temperature sensor 12 and the inlet water Pressure sensor 13 is positioned at the inlet end of described microchannel box group 3, and described outlet temperature sensor 14 and outlet water pressure sensor 15 are positioned at the outlet end of described microchannel box group 3; Described optical data collector comprises microscope 19, camera Instrument 17 and infrared thermal imager 18, described camera 17 is installed on the described microscope 19, and described microscope 19 and described infrared thermal imager 18 are respectively positioned at the front and rear of described microchannel box group 3; The time signal output end of camera 17, the time signal output end of described infrared thermal imager 18 and the data output end of described data acquisition instrument 6 are connected with the input end of described synchronizer 20 respectively, and the time signal output end of described camera 17 The image signal output end, the image signal output end of the infrared thermal imager 18 and the data output end of the synchronizer 20 are respectively connected to the input end of the data analyzer 7 . .

The fluid supply control group includes a water pump 8, a first filter 9, a regulating valve 10 and a second filter 11, and the water pump 8, the first filter 9, the regulating valve 10 and the second filter The flow meter 16 is arranged on the pipeline between the first filter 9 and the regulating valve 10, and is connected with the outlet end of the first filter 9 and the regulating valve The inlet port of 10 is fluidly connected; the outlet port of the liquid storage tank 1 is in fluid communication with the inlet port of the water pump 8; the outlet port of the second filter 11 is connected with the inlet port of the microchannel box group 3 Fluid conduction.

As shown in Figures 2 to 4, the microchannel box group 3 includes an upper cover plate 3-1, a lower base plate 3-2, a left side plate 3-3, a right side plate 3-4, and a front side plate 3-5 and the rear side plate 3-6; the left side plate 3-3 and the right side plate 3-4 are respectively fixed and bonded to the left and right sides of the lower bottom plate 3-2, and the front side plate 3 -5 and the rear side plate 3-6 are respectively fixed and bonded to the front side and the rear side of the lower bottom plate 3-2, and the upper cover plate 3-1 is located at the left side plate 3-3 and the right side plate 3-4. The upper end surfaces of the front side plate 3-5 and the rear side plate 3-6, and detachably connect the left side plate 3-3, the right side plate 3-4, the front The upper end surfaces of the side panels 3-5 and the rear side panels 3-6.

The lower bottom surface of the upper cover plate 3-1 has a left upper rib 3-7 and a right upper rib 3-8; the upper surface of the lower bottom plate 3-2 has a left lower rib 3-9 and a right lower rib 3- 10. The upper left rib 3-7 is located directly above the lower left rib 3-9, and the upper right rib 3-8 is located directly above the lower right rib 3-10; the upper left rib 3-7 and The upper right rib 3-8 has an inverted concave structure 3-19, the lower left rib 3-9 and the lower right rib 3-10 have an upward convex structure 3-20; the upper left rib 3 - The concave-convex structure 3-19 of -7 cooperates with the convex-convex structure 3-20 of the lower left rib 3-9, and the concave-shaped structure 3-20 of the upper right rib 3-8 19 cooperates with the convex structure 3-20 of the lower right rib 3-10 to form a left fixed gap 3-16 of a microchannel structure and a right fixed gap 3-17 of a microchannel structure with a height of 1-2 mm.

The left side of the upper cover plate 3-1, the left side of the lower bottom plate 3-2, the left side plate 3-3, the left side of the front side plate 3-5, the rear side plate 3 -6 The first cavity 3-A is formed between the left side, the left upper rib 3-7 and the left lower rib 3-9; the upper cover 3-1, the lower bottom 3-2, A second cavity 3-B is formed between the left upper rib 3-7, the right upper rib 3-8, the left lower rib 3-9 and the right lower rib 3-10; The right side of the upper cover plate 3-1, the right side of the lower bottom plate 3-2, the right side of the front side plate 3-5, the right side of the rear side plate 3-6, the right upper rib 3-8. A third cavity 3-C is formed between the lower right rib 3-10 and the right side plate 3-4; the first cavity 3-A and the third cavity 3-C is provided with a spoiler; the outlet end of the second filter 11, the first cavity 3-A, the second cavity 3-B, the third cavity 3-C and the liquid collection tank 5 in sequence; the first cavity 3-A and the third cavity 3-C are provided with spoilers; the first cavity 3-A and the The second cavity 3-B is fluidly connected through the left fixed gap 3-16 of the microchannel structure; the second cavity 3-B and the third cavity 3-C are connected through the microchannel structure. The right fixed slit 3-17 of the passage structure is fluidly connected.

The plate surface of the left side plate 3-3 is provided with a circular cross-section inlet of the microchannel box group 3, the circular cross-section inlet is a threaded hole, and the nominal diameter of the threaded hole is M8, and the right side plate 3 -4 is provided with a circular cross-section outlet of the microchannel box group 3 on the plate surface, the circular cross-section outlet is a threaded hole, and the nominal diameter of the threaded hole is M8, and the outlet end of the second filter 11 passes through the The circular cross-section inlet on the left side plate 3-3 is in fluid communication with the first cavity 3-A, and the circular cross-section outlet on the right side plate 3-4 is in fluid communication with the liquid collection tank 5 Fluid conduction; a threaded hole is opened on the surface of the front side plate 3-5 facing the first cavity 3-A, and the inlet water pressure sensor 13 is fitted with the internal thread of the threaded hole, The nominal diameter of the threaded hole is M12, and a threaded hole is opened on the surface of the front side plate 3-5 facing the third cavity 3-C, and the outlet water pressure sensor 15 is installed with the inner thread of the threaded hole. , the nominal diameter of the threaded hole is M12; the front side plate 3-5 is facing the second cavity 3-B with an installation gap 3-18; the rear side plate 3-6 is facing the second cavity The plate surface of the first cavity 3-A is provided with a threaded hole, and the inlet temperature sensor 12 is installed in the threaded hole. The nominal diameter of the threaded hole is M12, and the rear side plate 3-6 is facing The plate surface of the third cavity 3-C is provided with a threaded hole, and the outlet temperature sensor 14 is installed in the threaded hole, and the nominal diameter of the threaded hole is M12; the upper cover plate 3-1 is facing There are 4 threaded holes on the plate surface of the second cavity 3-B, and the nominal diameter of the threaded holes is M12; on the plate surface of the lower bottom plate 3-2 facing the second cavity 3-B There are 4 threaded holes, and the nominal diameter of the threaded holes is M12.

As shown in Figures 9 to 13, the length of the upper cover 3-1 is 136 mm and the width is 40 mm; the thickness of the upper cover 3-1 at the top of the first cavity 3-A, the The thickness of the upper cover plate 3-1 at the top of the third cavity 3-C, the thickness of the lower bottom plate 3-2 at the bottom of the first cavity 3-A, the thickness of the third cavity The thickness of the lower base plate 3-2 at the bottom of 3-C, the thickness of the front side plate 3-5, the thickness of the rear side plate 3-6, the thickness of the left side plate 3-3 The thickness and the thickness of the right side plate 3-4 are both 8mm, the thickness of the upper cover plate 3-1 at the top of the second cavity 3-B and the thickness of the bottom of the second cavity 3-B The thickness of the lower bottom plate 3-2 is 6mm; the thickness of the left upper rib 3-7 and the right upper rib 3-8 is 8mm, and the left side of the left upper rib 3-7 The distance d1 between the surface and the left end surface of the upper cover plate 3-1 is 40mm, the distance d2 between the right side of the left upper rib 3-7 and the left side of the right upper rib 3-8 is 40mm, and the The distance d3 between the right side of the upper right rib 3-8 and the right end surface of the upper cover plate 3-1 is 40mm; the width of the concave structure 3-19 and the convex structure 3-20 are both 20mm, the depth of the inverted concave structure 3-19 is 6mm; the length of the lower bottom plate 3-2 is 120mm, the width is 40mm, the left lower rib 3-9 and the right lower rib 3- The rib thickness of 10 is 8mm, the distance d4 between the left side of the left lower rib 3-9 and the left end surface of the lower bottom plate 3-2 is 32mm, and the right side of the left lower rib 3-9 and the The distance d5 between the left side of the lower right rib 3-10 is 40 mm, and the distance d6 between the right side of the lower right rib 3-10 and the right end face of the lower bottom plate 3-2 is 32 mm; The height of the left side plate 3-3 and the right side plate 3-4 is 30mm, the width of the left side plate 3-3 and the right side plate 3-4 is 40mm, and the center of circle of the circular cross-section inlet and The distance between the bottom surface of the left side plate 3-3 and the distance d7 between the center of the outlet of the circular cross section and the bottom surface of the right side plate 3-4 is 19 mm, and the center of the entrance of the circular cross section is located at the The transverse center of the left side plate 3-3, the center of the outlet of the circular cross section is located at the transverse center of the right side plate 3-4; the front side plate 3-5 and the rear side plate 3-6 The length is 136mm, and the width is 38mm; the distance d8 between the threaded hole circle center of the inlet water pressure sensor 13 and the outlet water pressure sensor 15 and the lower end surface of the front side plate 3-5 is 19mm, and the inlet water pressure sensor is installed The distance d9 between the center of the threaded hole of the temperature sensor 12 and the outlet temperature sensor 14 and the lower end surface of the rear side plate 3-6 is 19mm, and the center of the threaded hole of the inlet water pressure sensor 13 is installed on the same side as the front side. The distance d10 of the left end surface of the plate 3-5 is 23mm, and the distance d11 between the center of the threaded hole where the outlet water pressure sensor 15 is installed and the right end surface of the front side plate 3-5 The distance d12 between the center of the threaded hole where the inlet temperature sensor 12 is installed and the left end face of the rear side plate 3-6 is 23 mm, and the center of the threaded hole where the outlet temperature sensor 14 is installed is connected to the center of the rear side plate 3-6. The distance d13 of the right end surface of -6 is 23 mm.

As shown in Figures 7 and 8, a microchannel heat exchange module 3-11 is tightly fitted in the second cavity 3-B, and the fluid inlet end of the microchannel heat exchange module is connected to the In the left fixed gap 3-16 of the structure, the fluid inlet end of the microchannel heat exchange module is located in the right fixed gap 3-17 of the microchannel structure; the microchannel heat exchange module 3-11 includes a constant wall temperature microchannel Heat exchange module and constant heat flow microchannel heat exchange module.

The constant wall temperature microchannel heat exchange module includes a microchannel structure 3-12 and a condensate head 3-13, the condensate head 3-13 is located on the upper surface of the microchannel structure 3-12, and the microchannel structure The left end of 3-12 is tightly fitted in the left fixed gap 3-16 of the microchannel structure, and the right end of the microchannel structure 3-12 is tightly fitted in the right fixed gap 3-17 of the microchannel structure.

The constant heat flow microchannel heat exchange module includes a microchannel structure 3-12, an electrothermal film 3-14 and a plastic heat insulation board 3-15, and the electrothermal film 3-14 is located on the upper surface of the microchannel structure 3-12. The plastic insulation board 3-15 is located on the upper surface of the electrothermal film 3-14; the left end of the microchannel structure 3-12 is tightly fitted in the left fixed gap 3-16 of the microchannel structure, and the microchannel structure The right end of the structure 3-12 is tightly fitted in the right fixed gap 3-17 of the microchannel structure; the current output terminal and the current input terminal of the electric heating film 3-14 are respectively connected to the input terminal and the output terminal of the DC power supply 4 .

As shown in Figures 2 to 3, the lower base plate 3-2 is located at the left side plate 3-3, the right side plate 3-4, the front side plate 3-5 and the rear side plate 3- 6, and the lower surface of the lower bottom plate 3-2, the lower end surface of the left side plate 3-3, the lower end surface of the right side plate 3-4, the lower end surface of the front side plate 3-5 and the The five lower end surfaces of the rear side plate 3-6 are flush, and the four sides of the lower bottom plate 3-2 are connected to the left side plate 3-3, the right side plate 3-4, and the front side plate 3. -5 and the inner surface of the rear side plate 3-6 are liquid-tightly bonded, and the upper cover plate 3-1 is clamped on the inner side of the front side plate 3-5 and the rear side plate 3-6 between the boards, and the left end of the upper cover plate 3-1 is pressed against the upper end surface of the left side plate 3-3, and the right end of the upper cover plate 3-1 is pressed against the right side plate 3-4 on the upper end surface; the width of the upper left rib 3-7, the upper right rib 3-8, the lower left rib 3-9 and the lower right rib 3-10 is 40mm, The left upper rib 3-7, the right upper rib 3-8, the left lower rib 3-9 and the right lower rib 3-10 are clamped between the front side plate 3-5 and the Between the inner side panels of the rear side panels 3-6.

working principle:

Example 1

Prepare nanofluids of different concentrations, place them in the liquid storage tank 1, turn on the coil heater 2 to heat the nanofluids in the liquid storage tank 1, and when heated to a certain temperature, turn on the water pump 8, and the nanofluid in the liquid storage tank 1 The fluid is filtered for the first time through the first filter 9, and the filtered nanofluid passes through the regulating valve 10 to adjust the flow rate of the nanofluid, and then enters the second filter 11, and the nanofluid after the secondary filtration enters the microchannel box Group 3, enter the first cavity 3-A from the inlet of the left side plate 3-3 of the microchannel box group 3, and the inlet water pressure sensor 13 installed on the front side plate 3-5 of the first cavity 3-A detects The water pressure at the inlet end, the inlet temperature sensor 12 installed on the rear side plate 3-6 of the first chamber 3-A detects the temperature at the inlet end; the nanofluid flowing into the first chamber 3-A is left fixed through the microchannel structure The slit 3-16 enters the microchannel heat exchange module 3-11 for heat exchange. At this time, the camera 17 on the infrared thermal imager 18 in front of the microchannel box group 3 and the microscope 19 behind the microchannel box group 3 Start to record the heat exchange in the microchannel heat exchange module 3-11; the nanofluid after heat exchange flows out from the outlet of the microchannel heat exchange module 3-11, and enters the third cavity through the right fixed gap 3-17 of the microchannel structure In the body 3-C, the outlet water pressure sensor 15 installed on the front side plate 3-5 of the third cavity 3-C detects the water pressure at the outlet end, and is installed on the rear side plate 3-5 of the third cavity 3-C. The outlet temperature sensor 14 on 6 detects the temperature at the outlet end; then the nanofluid in the third chamber 3-C flows out from the outlet of the right side plate 3-4, enters the liquid collection tank 5, and completes the mass transfer process of the nanofluid.

At the same time, the data acquisition instrument 6 collects the flow q _m of the nanofluid from the flow meter 16, the temperature t in of the nanofluid at the inlet end of the microchannel box group measured by the inlet temperature sensor 12, and the temperature t _in of the nanofluid measured by the inlet water pressure sensor 13. The temperature P _in at the inlet end of the microchannel box group, the temperature t _out of the outlet temperature sensor 14 at the inlet end of the microchannel box group, the temperature P _out of the outlet water pressure sensor 15 at the inlet end of the microchannel box group, and the optical data collector collects the microchannel box The imaging situation of the infrared thermal imager 18 in front of group 3 and the camera 17 on the microscope 19 at the rear of the microchannel box group 2 record the flow image in the microchannel heat exchange module 3-11. The time signal output end of camera 17, the time signal output end of infrared thermal imager 18 and the data output end of data acquisition instrument 6 are connected with the input end of synchronizer 20 respectively, the image signal output end of described camera 17, all The image signal output end of the infrared thermal imager 18 and the data output end of the synchronizer 20 are respectively connected to the input end of the data analyzer 7 . The time output signal of the camera 17, the time output signal of the infrared thermal imager 18 and the heat exchange data signal of the data acquisition instrument 6 enter the synchronizer 18 for synchronization to reduce errors, and then the image signal of the camera 17, the infrared thermal imager 18 image signals and the time output signal of the camera 17 synchronized in the synchronizer, the time output signal of the infrared thermal imager 18 and the heat exchange data signal of the data acquisition instrument 6 are sent to the data analyzer 7 for analysis, and then the micro Channel heat transfer efficiency and heat transfer.

When the microchannel heat exchange module 3-11 is a constant wall temperature microchannel heat exchange module, the inlet port and the outlet port of the condensate head 3-13 on the upper surface of the microchannel structure 3-12 need to be opened and communicated with the excess water produced by heating and boiling. For the steam, t _w is obtained by controlling the wall temperature of the microchannel structure 3-12 to be constant by controlling the fixed condensation point corresponding to the condensed components of the steam.

When the microchannel heat exchange module 3-11 is a constant heat flow microchannel heat exchange module, the electrothermal film 3-14 on the upper surface of the microchannel structure 3-12 is heated by the external DC power supply 4 and displayed by the voltmeter on the DC power supply 4 The voltage U and the current I shown by the ammeter can obtain the electric heating power of the electrothermal film 3-14. heating power.

Spoilers are installed in the first cavity 3-A and the second cavity 3-C to make the temperature of the inlet of the microchannel heat exchange module 3-11 uniform and the composition of the nanofluid uniform.

The material of the microchannel box group 3 is poor thermal conductivity, such as transparent acrylic plate or glass with strong light transmission. It can be considered that the microchannel box group 3 is adiabatic, and the internal temperature distribution of the microchannel box group 3 captured by the infrared thermal imager 18 is: the temperature on the surface of the microchannel heat exchange module 3-11 has nothing to do with the temperature of the microchannel box group 3 itself .

The resistance of the electrothermal film 3-14 is very small, so when the external direct current power supply 4 is heated during use, the circuit should adopt the ammeter external connection method, and ignore the current flowing through the voltmeter.

The cavity of the condensate head 3-13 is made of copper, the material has strong thermal conductivity and the structure size is small, so the temperature at the edge is also similar to the wall temperature t _w of the microchannel structure 3-12.

Example 2

In order to study the heat transfer efficiency and heat transfer capacity of nanofluids with different particle sizes in microchannel heat exchange modules 3-11 with different structures and different pore sizes, it is only necessary to strengthen the microchannel box group 3 in the thermal test detection device for microchannel nanofluids Make adjustments.

1. Change the microchannel heat exchange module 3-11

According to different requirements in the test, it is necessary to change the size and structure of the microchannel heat exchange module 3-11, the microchannel structure 3-12, and the microchannel heat exchange module 3-11 with different heat transfer modes. In the device of the present invention, the microchannel heat exchange module 3-11 can be assembled separately, and then the groove opened on the plate surface of the second cavity 3-B by the front side plate 3-5 will The microchannel heat exchange module 3-11 is installed in the second cavity 3-B in the microchannel box group 3. During the installation process, it can pass through the four holes on the upper cover plate 3-1 and the lower bottom plate 3-2. The microchannel heat exchange module 3-11 is adjusted so that the inlet end of the microchannel heat exchange module 3-11 closely matches the left fixed gap 3-16 of the microchannel structure to prevent the seepage of nanofluid, and the microchannel heat exchange module 3-11 The outlet end of 11 closely cooperates with the right fixed slit 3-17 of the microchannel structure to prevent the seepage of the nanofluid. Very easy to operate.

2. Change the gap between ribs

The upper cover plate 3-1 can be taken off from the left side plate 3-3, the right side plate 3-4, the front side plate 3-5 and the rear side plate 3-6, by adjusting the upper left side plate on the upper cover plate 3-1 The left fixed gap 3-16 and the microchannel structure in which the ribs 3-7, the upper right ribs 3-8 and the left lower ribs 3-9 on the lower bottom plate 3-2 and the lower right ribs 3-10 cooperate with each other. The structure right fixes the gap 3-17 to adapt to the size of the microchannel heat exchange module 3-11. The split design of the upper cover plate 3-1, the lower base plate 3-2, the left side plate 3-3, the right side plate 3-4, the front side plate 3-5 and the rear side plate 3-6 can facilitate the test process Replacement of the upper cover plate 3-1.

Example 3

The microchannel nanofluid enhanced heat transfer test device of the present invention is used in the microchannel nanofluid enhanced heat transfer test, and the specific test results are as follows.

Heat balance type:

Q＝hAΔt _m ＝q _m c _p (t _in -t _out )

Among them, Q is the heat transfer rate of the liquid, unit W, h is the convective heat transfer coefficient, unit W/m ² ·K, A is the heat transfer area, unit m ² , Δt _m is the arithmetic mean temperature difference, unit K, q _m is the mass flow rate of the fluid in convective heat exchange, unit kg/s, c _p is the specific heat capacity of the liquid at constant pressure, unit J/(kg K), t _in is the inlet temperature of the liquid inlet microchannel box group, unit K, t _out is the outlet temperature of the liquid flowing out of the microchannel box group, in K.

According to the heat balance formula, the inlet temperature t _in of the nanofluid entering the microchannel box group is measured by the inlet temperature sensor 12, the outlet temperature t _out of the nanofluid entering and leaving the microchannel box group is measured by the outlet temperature sensor 14, and the flow meter 16 measures the temperature passing through the microchannel box group The mass flow rate q _m ; and then calculate the heat transfer heat Q and heat transfer coefficient h of different flow rates, insoluble wall temperature, different heat flow, different nanofluids, different nanofluid concentrations, and different microchannel structures, so as to obtain related influencing factors. In this system, since the concentration of nanofluid is very small, the specific heat capacity c _p of nanofluid at constant pressure is approximately the specific heat capacity of water under atmospheric pressure. By measuring the inlet water pressure sensor 13 and the outlet water pressure sensor 15 to measure the pressure change of the nanofluid in the microchannel box group, the heat transfer amount and heat transfer coefficient can be corrected.

1. Effect of wall temperature on heat transfer and heat transfer coefficient

As shown in Table 1 and Figure 14, as the wall temperature increases, the heat transfer Q between the wall surface and water and nanofluid increases to 0.9kJ and 1.1kJ respectively; The coefficient h is around 40000W/(m ² ·K) and 50000W/(m ² ·K) respectively, and does not change with the temperature difference; under the same wall temperature setting, the heat transfer coefficient of nanofluid is significantly greater than that of water. The nanofluid is SiO ₂ , and the volume ratio of SiO ₂ is 0.03, that is, V _SiO2 /(V _SiO2 +V _H2O )=0.03.

The reason why the heat transfer coefficient does not change is that the system structure has not changed, and the heat transfer medium has not changed; when the nanofluid is compared with water, the heat transfer medium is relatively different, and the heat transfer coefficient of the solid particles in the nanofluid is significantly greater than that of the fluid , which enhances the heat transfer of the mixed flow.

Table 1

2. Effect of heat flow on heat transfer and heat transfer coefficient

As shown in Table 2 and Figure 15, as the wall temperature increases, the heat transfer Q between the wall surface and water and nanofluid increases to 2.189kJ and 2.199kJ respectively; The thermal coefficients are around 39600W/(m ² ·K) and 40000W/(m ² ·K) respectively, and do not change with the temperature difference; different from Figure 1, the difference in heat transfer and heat transfer coefficient between nanofluid and water under the same heat flow is small . The nanofluid is SiO ₂ , and the volume ratio of SiO ₂ is 0.03, that is, V _SiO2 /(V _SiO2 +V _H2O )=0.03.

The reason why the heat transfer coefficient does not change is that the system structure has not changed, and the heat transfer medium has not changed; when the nanofluid is compared with water, the heat transfer medium is relatively different, and the heat transfer coefficient of the solid particles in the nanofluid is significantly greater than that of the fluid , which strengthens the heat transfer of the mixed flow, but unlike the constant wall temperature, the energy loading method makes the metal wall temperature gradually change, which weakens the influence of the fluid heat transfer capacity, so the difference between the heat transfer coefficient and the heat transfer amount is small.

Table 2

3. Influence of inlet velocity on heat transfer and heat transfer coefficient

As shown in Table 3 and Figure 16, as the inlet flow rate u increases, the heat transfer Q between the wall surface and water and nanofluid increases to 0.633kJ and 0.777kJ respectively; the heat transfer coefficient increases significantly with the increase of flow rate ; At the same flow rate, the heat transfer coefficient and heat transfer capacity of nanofluid are significantly greater than that of water. The nanofluid is SiO ₂ , and the volume ratio of SiO ₂ is 0.03, that is, V _SiO2 /(V _SiO2 +V _H2O )=0.03.

As the flow rate increases, the heat capacity of the fluid increases, and the relative velocity to the wall increases. Although the temperature difference between the inlet and outlet decreases, the increase in the flow rate increases the heat transfer capacity of the system, resulting in significant changes in the heat transfer coefficient and heat transfer capacity. .

table 3

4. Effect of Reynolds number Re on heat transfer and heat transfer coefficient

As shown in Table 4 and Figure 17, with the increase of Re, the heat transfer rate increases; at the same time, under the same structure, the heat transfer coefficient increases with the increase of Re; the same Re In this case, the heat transfer coefficient and heat transfer capacity of nanofluid are significantly greater than that of water, and the law is basically consistent with the influence of variable flow in Figure 16. The nanofluid is SiO ₂ , and the volume ratio of SiO ₂ is 0.03, that is, V _SiO2 /(V _SiO2 +V _H2O )=0.03.

The Reynolds number is affected by the flow rate, equivalent diameter and kinematic viscosity. The equivalent diameter is determined by the system structure and does not change. Since the temperature of the fluid changes little and the factors affecting the kinematic viscosity are not obvious, the most obvious factor affecting the Reynolds number is the channel. Therefore, the graph of the change with Reynolds number is very similar to the change with flow velocity.

Table 4

5. Effect of different types of nanoparticles on heat transfer and heat transfer coefficient

As shown in Table 5 and Figure 18, with the change of nanofluid, the heat transfer of water, SiO ₂ nanofluid and Al ₂ O ₃ nanofluid are 0.633kJ, 0.777kJ and 0.971kJ respectively; In the case of water, SiO ₂ and Al ₂ O ₃ , the heat transfer coefficient has obvious changes; under the same working conditions, the heat transfer coefficient and heat transfer amount of SiO ₂ are significantly smaller than those of Al ₂ O ₃ . The volume ratio of the SiO ₂ nanofluid is 0.03, that is, V _SiO2 /(V _SiO2 +V _H2O )=0.03, and the volume ratio of the Al ₂ O ₃ nanofluid is 0.03, that is, V _Al2O3 /(V _Al2O3 +V _H2O )=0.03.

Compared with water, the heat transfer coefficient of solid particles in nanofluid is significantly greater than that of fluid, which strengthens the heat transfer of mixed flow; the thermal conductivity of different nanoparticle materials is different, and the thermal conductivity of Al ₂ O ₃ is significantly greater than that of SiO ₂ , resulting in a difference between the heat transfer coefficient and There is a large difference in heat transfer.

table 5

6. Effects of different concentrations of nanoparticles on heat transfer and heat transfer coefficient

As shown in Table 6 and Figure 19, as the nanofluid volume ratio increases, the heat transfer heat and heat transfer coefficient increase to 0.3157kJ and 22711W/(m ² ·K) respectively. Table 6 shows the volume ratio of the Al ₂ O ₃ nanofluid, that is, V _Al2O3 /(V _Al2O3 +V _H2O ).

The increase in the volume ratio increases the number of nanoparticles and strengthens the total heat transfer capacity of the mixed flow, thereby increasing the heat transfer coefficient and heat transfer capacity.

Table 6

7. The influence of the number of microchannels on heat transfer and heat transfer coefficient

As shown in Table 7 and Figure 20, when the channel flow rate remains constant, as the number of channels increases, the heat transfer between water and SiO ₂ nanofluid increases to 0.674kJ and 0.642kJ respectively; increase, the total heat transfer area increases, the heat transfer coefficient per unit heat transfer area decreases, and the water and SiO ₂ nanofluid transfer coefficients decrease to 48988W/(m ² ·K) and 46572W/(m ² ·K) respectively. The volume ratio of the SiO ₂ nanofluid is 0.03, that is, V _SiO2 /(V _SiO2 +V _H2O )=0.03.

The increase in the number of channels makes the fluid flow more uniform and gentle, reduces the heat transfer capacity with the wall, so the heat transfer coefficient decreases, and the increase in the flow rate increases the total heat transfer.

Table 7

8. Influence of Microchannel Diameter on Heat Transfer Capacity and Heat Transfer Coefficient

As shown in Table 8 and Figure 21, when the channel flow rate is constant, as the channel diameter increases, the heat transfer coefficient and heat transfer amount increase, and the slope gradually decreases. After the pipe diameter increases from 0.3mm to 0.8mm, The heat transfers between water and SiO ₂ nanofluids increased to 0.741KJ and 0.748KJ, respectively, and the heat transfer coefficients increased to 46461W/(m ² ·K) and 46879W/(m ² ·K), respectively. The volume ratio of the SiO ₂ nanofluid is 0.03, that is, V _SiO2 /(V _SiO2 +V _H2O )=0.03.

When the flow rate is constant, the increase of the diameter of the microchannel leads to the increase of the flow rate, the increase of the heat carrying capacity of the fluid, and the increase of the heat transfer coefficient and heat transfer capacity; higher than the latter.

Table 8

Overall analysis, the results obtained under different wall temperature conditions are more significant. The microchannel structure, flow rate and fluid type determine the heat transfer coefficient. When the temperature difference between the inlet and outlet decreases, the total heat transfer coefficient may increase due to the increase of the flow rate.

Apparently, the above-mentioned embodiments are only examples for clear description, rather than limiting the implementation. For those of ordinary skill in the art, on the basis of the above description, other changes or changes in different forms can also be made. It is not necessary and impossible to exhaustively list all the implementation manners here. And the obvious changes or changes derived therefrom are still within the scope of protection of the present invention.

Claims (10)

1. a kind of microchannel nano-fluid enhanced heat exchange experiment test device, which is characterized in that the microchannel nano-fluid is strong Change heat transfer experiments test device include fluid reservoir (1), coil heater (2), fluid supply control group, microchannel box group (3), DC power supply (4), DATA REASONING analysis group and liquid collecting fill (5)；The coil heater (2) is located in the fluid reservoir (1) It is interior, between the fluid reservoir (1), fluid supply control group, the microchannel box group (3) and liquid collecting filling (5) successively Fluid communication；The DC power supply (4) is electrically connected with the microchannel box group (3)；The DATA REASONING analysis group includes optics Data collection instrument, data collecting instrument (6), synchronizer (19), hydraulic pressure and temperature-measuring element and data analyzer (7), the water Pressure and temperature-measuring element include inlet temperature sensor (12), import hydraulic pressure sensor (13), outlet temperature sensor (14), Outlet hydraulic pressure sensor (15) and for measuring the flowmeter (16) for flowing through fluid supply control group fluid flow, it is described into The output end of mouth temperature sensor (12), output end, the outlet temperature sensor of the import hydraulic pressure sensor (13) (14) output end of output end, the output end of the outlet hydraulic pressure sensor (15) and the flowmeter (16) respectively with it is described The input terminal of data collecting instrument (6) connects；The inlet temperature sensor (12) and the import hydraulic pressure sensor (13) are located at The input end of the microchannel box group (3), the outlet temperature sensor (14) and outlet hydraulic pressure sensor (15) are located at described The outlet end of microchannel box group (3)；The optical data collection instrument includes microscope (19), video camera (17) and infrared thermal imaging Instrument (18), the video camera (17) are mounted on the microscope (19), the microscope (19) and the infrared thermography (18) it is located at the front and back of the microchannel box group (3)；It is the time signal output end of the video camera (17), described The time signal output end of infrared thermography (18) and the data output end of the data collecting instrument (6) respectively with it is described synchronous The input terminal of device (20) connects, the image signal output end of the video camera (17), the image of the infrared thermography (18) The data output end of signal output end and the synchronizer (20) is connect with the input terminal of the data analyzer (7) respectively.

2. nano-fluid enhanced heat exchange experiment test device in microchannel according to claim 1, which is characterized in that the stream Body supply control group includes water pump (8), first filter (9), regulating valve (10) and the second filter (11), the water pump (8), Fluid communication successively between the first filter (9), the regulating valve (10) and second filter (11)；The flow (16) are counted to be arranged on pipeline between the first filter (9) and the regulating valve (10), and with first filter (9) The arrival end fluid communication of outlet end and the regulating valve (10)；The outlet end of the fluid reservoir (1) enters with the water pump (8) Mouth end fluid communication；The arrival end fluid communication of the outlet end of second filter (11) and the microchannel box group (3).

3. nano-fluid enhanced heat exchange experiment test device in microchannel according to claim 1, which is characterized in that described micro- Channel box group (3) include upper cover plate (3-1), lower plate (3-2), left plate (3-3), right plate (3-4), front side board (3-5) and Back side panel (3-6)；The left plate (3-3) and the right plate (3-4) fix the left side for being bonded in the lower plate (3-2) respectively Side and right side, the front side board (3-5) and back side panel (3-6) fix front side and the rear side for bonding the lower plate (3-2) respectively, The upper cover plate (3-1) is located at the left plate (3-3), the right plate (3-4), the front side board (3-5) and the rear side The upper surface of plate (3-6), and be detachably connected the left plate (3-3), the right plate (3-4), the front side board (3-5) and The upper surface of the back side panel (3-6).

4. nano-fluid enhanced heat exchange experiment test device in microchannel according to claim 3, which is characterized in that on described The bottom surface of cover board (3-1) has upper left fin (3-7) and upper right fin (3-8)；There is lower-left in the upper surface of the lower plate (3-2) Fin (3-9) and bottom right fin (3-10), the upper left fin (3-7) are located at the surface of lower-left fin (3-9), the upper right Fin (3-8) is located at the surface of bottom right fin (3-10)；The upper left fin (3-7) and the upper right fin (3-8) are in Concave structure (3-19), the lower-left fin (3-9) and the bottom right fin (3-10) present convex structure (3-20)；The left side The inverted concave structure (3-19) of upper fin (3-7) and the convex-shaped structure male-female engagement of the lower-left fin (3-9) and The convex-shaped structure (3-20) of the inverted concave structure (3-19) and the bottom right fin (3-10) of the upper right fin (3-8) Male-female engagement is respectively formed the left fixed gap (3-16) of microchannel structure and the right fixed seam of microchannel structure that height is 1-2mm Gap (3-17).

5. nano-fluid enhanced heat exchange experiment test device in microchannel according to claim 4, which is characterized in that on described The left side cover board (3-1), the left side the lower plate (3-2), the left plate (3-3), the left side the front side board (3-5), The first cavity (3-A) is surrounded between back side panel (3-6) left side, the upper left fin (3-7) and lower-left fin (3-9)； The upper cover plate (3-1), the lower plate (3-2), the upper left fin (3-7), the upper right fin (3-8), the lower-left The second cavity (3-B) is surrounded between fin (3-9) and the bottom right fin (3-10)；It is upper cover plate (3-1) right side, described The right side lower plate (3-2), the right side the front side board (3-5), the right side the back side panel (3-6), the upper right fin (3- 8), third cavity (3-C) is surrounded between the bottom right fin (3-10) and the right plate (3-4)；Second filter (11) outlet end, first cavity (3-A), second cavity (3-B), the third cavity (3-C) and the liquid collecting Fill (5) fluid communication successively；It is provided with spoiler in first cavity (3-A) and the third cavity (3-C)；Described first Pass through left fixed gap (3-16) fluid communication of the microchannel structure between cavity (3-A) and second cavity (3-B)；Institute It states between the second cavity (3-B) and the third cavity (3-C) through right fixed gap (3-17) fluid of the microchannel structure Conducting.

6. nano-fluid enhanced heat exchange experiment test device in microchannel according to claim 5, which is characterized in that the left side The circular cross section inlet port of the microchannel box group (3) is provided in the plate face of side plate (3-3), circular cross section inlet port is screw thread Hole, threaded hole nominal diameter are M8, and the circle that the microchannel box group (3) is provided in the plate face of the right plate (3-4) is horizontal Cross-sectional exit, circular cross section outlet are threaded hole, and threaded hole nominal diameter is M8, the outlet end of second filter (11) Pass through circular cross section inlet port on the left plate (3-3) and the first cavity (3-A) fluid communication, the right plate Circular cross section outlet on (3-4) fills (5) fluid communication with the liquid collecting；First described in the front side board (3-5) face Threaded hole is offered in the plate face of cavity (3-A), and the import hydraulic pressure sensor is installed in threaded hole screw-internal thread fit (13), threaded hole nominal diameter is M12, and the plate face of third cavity (3-C) described in the front side board (3-5) face offers spiral shell Pit, and the outlet hydraulic pressure sensor (15) is installed in threaded hole screw-internal thread fit, threaded hole nominal diameter is M12；It is described The plate face of second cavity (3-B) described in front side board (3-5) face offers installation gap (3-18)；Side plate (3-6) in the rear The plate face of first cavity (3-A) described in face offers threaded hole, and is equipped with the import temperature in threaded hole screw-internal thread fit Sensor (12) is spent, threaded hole nominal diameter is M12, in the rear the plate face of third cavity (3-C) described in side plate (3-6) face On offer threaded hole, and the outlet temperature sensor (14) is installed in threaded hole, threaded hole nominal diameter is M12； 4 threaded holes, threaded hole nominal diameter are offered in the plate face of the second cavity (3-B) described in the upper cover plate (3-1) face For M12；4 threaded holes are offered in the plate face of the second cavity (3-B) described in the lower plate (3-2) face, threaded hole is public Claim a diameter of M12.

7. nano-fluid enhanced heat exchange experiment test device in microchannel according to claim 3, which is characterized in that on described A length of 136mm of cover board (3-1), width 40mm；The upper cover plate (3-1) board thickness at the top of first cavity (3-A), The upper cover plate (3-1) board thickness, the bottom first cavity (3-A) at the top of the third cavity (3-C) it is described under Bottom plate (3-2) board thickness, the lower plate (3-2) board thickness of the bottom the third cavity (3-C), the front side board (3-5) board thickness, the back side panel (3-6) board thickness, the left plate (3-3) board thickness and the right plate (3- 4) board thickness is 8mm, the upper cover plate (3-1) board thickness and described second at the top of second cavity (3-B) The lower plate (3-2) board thickness of the bottom cavity (3-B) is 6mm；The upper left fin (3-7) and the upper right fin The fin thickness of (3-8) is 8mm, and the left side of the upper left fin (3-7) is with the left side distance d1 of upper cover plate (3-1) 40mm, the right side of the upper left fin (3-7) is 40mm with the left side distance d2 of the upper right fin (3-8), described The right side of upper right fin (3-8) is 40mm with the right side distance d3 of the upper cover plate (3-1)；The inverted concave structure (3-19) and the width of the convex-shaped structure (3-20) be 20mm, the inverted concave structure (3-19) depth be 6mm；Institute State a length of 120mm of lower plate (3-2), width 40mm, the fin of the lower-left fin (3-9) and the bottom right fin (3-10) Thickness is 8mm, and the lower-left fin left side (3-9) is 32mm with the left side distance d4 of the lower plate (3-2), described The right side of lower-left fin (3-9) is 40mm, the bottom right fin with the left side distance d5 of the bottom right fin (3-10) The right side of (3-10) is 32mm with the right side distance d6 of the lower plate (3-2)；The left plate (3-3) and right plate The height of (3-4) is that the width of 30mm, the left plate (3-3) and right plate (3-4) are 40mm, the circular cross section The center of circle of import is at a distance from the left plate (3-3) bottom surface and the center of circle and the right plate of circular cross section outlet The distance d7 of (3-4) bottom surface is 19mm, and the center of circle of the circular cross section inlet port is located at the transverse direction of the left plate (3-3) The center of circle at center, the circular cross section outlet is located at the transverse center of the right plate (3-4)；The front side board (3-5) and The a length of 136mm, width 38mm of the back side panel (3-6)；The import hydraulic pressure sensor (13) and the outlet hydraulic pressure are installed The threaded hole center of circle of sensor (15) equal d8 at a distance from the lower face the front side board (3-5) is 19mm, installs the import temperature Spend sensor (12) and the outlet temperature sensor (14) the threaded hole center of circle and back side panel (3-6) lower face away from It is 19mm from equal d9, the left side in the threaded hole center of circle and the front side board (3-5) of the import hydraulic pressure sensor (13) is installed Distance d10 be 23mm, install it is described outlet hydraulic pressure sensor (15) the threaded hole center of circle and the front side board (3-5) right end The distance d11 in face is 23mm, installs the left side in the threaded hole center of circle and the back side panel (3-6) of the inlet temperature sensor (12) The distance d12 of end face is 23mm, installs the threaded hole center of circle and the back side panel (3-6) of the outlet temperature sensor (14) The distance d13 of right side is 23mm.

8. nano-fluid enhanced heat exchange experiment test device in microchannel according to claim 6, which is characterized in that described Thermal Performance of Micro Channels module (3-11) is installed, the fluid inlet end of the Thermal Performance of Micro Channels module is located in the second cavity (3-B) In the left fixed gap (3-16) of microchannel structure, the fluid outlet of the Thermal Performance of Micro Channels module is located at the microchannel In the right fixed gap (3-17) of structure；The Thermal Performance of Micro Channels module (3-11) includes permanent wall temperature Thermal Performance of Micro Channels module and perseverance heat Flow Thermal Performance of Micro Channels module.

9. nano-fluid enhanced heat exchange experiment test device in microchannel according to claim 8, which is characterized in that the perseverance Wall temperature Thermal Performance of Micro Channels module includes microchannel structure (3-12) and condensation head (3-13), and the condensation head (3-13) is located at On the upper surface of the microchannel structure (3-12), the left end tight fit of the microchannel structure (3-12) is mounted on described micro- logical In the left fixed gap (3-16) of road structure, the right end tight fit of the microchannel structure (3-12) is mounted on the microchannel structure In right fixed gap (3-17).

10. nano-fluid enhanced heat exchange experiment test device in microchannel according to claim 8, which is characterized in that described Constant heat flow Thermal Performance of Micro Channels module includes microchannel structure (3-12), Electric radiant Heating Film (3-14) and plastic heat shield (3-15), described Electric radiant Heating Film (3-14) is located at the upper surface of microchannel structure (3-12), and the plastic heat shield (3-15) is located at the Electric radiant Heating Film The upper surface of (3-14)；The left end tight fit of the microchannel structure (3-12) is mounted on the left fixed gap of the microchannel structure In (3-16), the right end tight fit of the microchannel structure (3-12) is mounted on the right fixed gap (3-17) of the microchannel structure It is interior；The current output terminal and current input terminal of the Electric radiant Heating Film (3-14) input terminal and output end with DC power supply (4) respectively It is connected；The lower plate (3-2) is located at the left plate (3-3), the right plate (3-4), the front side board (3-5) and described Between back side panel (3-6), and the lower surface of the lower plate (3-2), the lower face the left plate (3-3), the right plate The lower face (3-4), the front side board lower face (3-5) are concordant with the back side panel lower face (3-6), the lower plate Four sides of (3-2) and the left plate (3-3), the right plate (3-4), the front side board (3-5) and the back side panel The inside plate face fluid-tight bonding of (3-6), the upper cover plate (3-1) are clamped in the front side board (3-5) and the back side panel (3-6) Inside plate face between, and the left end of the upper cover plate (3-1) is pressed on the upper surface of the left plate (3-3), described The right end of upper cover plate (3-1) is pressed on the upper surface of the right plate (3-4)；The upper left fin (3-7), the upper right rib The width of piece (3-8), the lower-left fin (3-9) and the bottom right fin (3-10) is 40mm, the upper left fin (3- 7), the upper right fin (3-8), the lower-left fin (3-9) and the bottom right fin (3-10) are clamped in the front side board Between (3-5) and the inside plate face of the back side panel (3-6).