A micro-channel heat exchange research device

Abstract

The application discloses a micro-channel heat exchange research device, which comprises a top plate, a bottom plate, a cold plate, a first temperature measuring structure and a first simulated heat source. The first temperature measuring structure is arranged at one end of the cover plate close to the base plate, and is used for measuring the inner wall surface temperature of the micro-channel. The first simulated heat source is used for directly contacting with the working medium flowing in the micro-channel and heating the working medium flowing in the micro-channel. The application can improve the measurement precision of heat flux density and local heat exchange coefficient.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of channels, in particular to a micro-channel heat exchange research device. BACKGROUND

[0002] In the existing micro-channel heat exchange research device, the micro-channel is arranged on one side of the base plate, and the heating surface is arranged on the other side of the base plate. The heat load applied by the heating surface cannot be uniformly and completely transmitted to the wall surface of the micro-channel. Part of the heat will diffuse to the area outside the micro-channel due to the solid heat conduction effect. It is extremely difficult to quantitatively measure or calculate this part of the heat, thereby increasing the measurement error of the heat flux density, thereby increasing the error of the critical heat flux density prediction model. The measurement of the local heat exchange coefficient is also the measurement of the temperature of the heating surface, rather than the measurement of the temperature of the wall surface in direct contact with the fluid. Such measurement will lead to the local heat exchange coefficient measured as the average heat exchange coefficient of the whole, which cannot accurately reflect the internal correlation between the two-phase flow pattern and the heat exchange process. However, the accurate local heat exchange coefficient, the critical heat flux density and the critical heat flux density prediction model play a crucial role in the design of the micro-channel heat exchange research device. SUMMARY

[0003] Therefore, it is necessary to provide a micro-channel heat exchange research device capable of accurately measuring the heat flux density and the local heat exchange coefficient.

[0004] A micro-channel heat exchange research device, comprising:

[0005] A top plate having a liquid inlet section and a liquid outlet section, the top plate further being provided with a first flow-through hole and a second flow-through hole, the liquid inlet section being in communication with the first flow-through hole, and the liquid outlet section being in communication with the second flow-through hole;

[0006] A bottom plate arranged at the bottom end of the top plate;

[0007] A cold plate, the cold plate comprising a base plate and a cover plate, the cover plate being arranged close to the top plate, the base plate being arranged at the bottom end of the cover plate, the cover plate being provided with a working medium inlet and a working medium outlet, the working medium inlet being in communication with the first flow-through hole, the working medium outlet being in communication with the second flow-through hole, and the base plate being provided with a channel at one end close to the cover plate, the channel comprising a liquid inlet channel, a micro-channel and a liquid outlet channel in sequence, the liquid inlet channel being in communication with the working medium inlet, and the liquid outlet channel being in communication with the working medium outlet;

[0008] A first temperature measurement structure arranged at one end of the cover plate close to the base plate, the first temperature measurement structure being used for measuring the wall surface temperature of the micro-channel; and

[0009] A first simulated heat source, the first simulated heat source being used for directly contacting the working medium flowing in the micro-channel and heating the working medium flowing in the micro-channel.

[0010] Optionally, the first simulated heat source comprises a first conductive probe and a metal film, the metal film is embedded in the inner wall of the channel, the number of the first conductive probe is two, the top plate is provided with a first fixing hole, the number of the first fixing hole is two, the first fixing hole and the first flow-through hole and the second flow-through hole are coaxially arranged respectively, the first conductive probe is correspondingly arranged in the first fixing hole and in contact with the metal film to supply power to the metal film, and the metal film is used to generate heat to heat the working medium flowing in the microchannel.

[0011] Optionally, the first temperature measuring structure comprises a plurality of temperature measuring sections, and the plurality of temperature measuring sections are arranged on the cover plate in a spaced manner along the flow direction of the working medium.

[0012] Optionally, the microchannel heat exchange research device further comprises a second simulated heat source and a second temperature measuring structure, the second simulated heat source is arranged at one end of the base plate away from the cover plate, the second simulated heat source is used to heat the outer wall surface of the channel to heat the working medium flowing in the channel, and the second temperature measuring structure is arranged at one end of the base plate away from the cover plate, and the second temperature measuring structure is used to measure the temperature of the outer wall surface of the channel.

[0013] Optionally, the second simulated heat source comprises a metal layer and a second conductive probe, the metal layer is arranged at one end of the base plate away from the cover plate, the number of the second conductive probe is at least two, the second conductive probe is correspondingly arranged in the second fixing hole and in contact with the metal layer to supply power to the metal layer, and the metal layer is used to supply power to the base plate to generate heat to heat the working medium flowing in the microchannel.

[0014] Optionally, the microchannel heat exchange research device further comprises a sealing ring, the top plate is further provided with a sealing ring groove, the sealing ring groove is coaxially arranged with the first fixing hole, the sealing ring is arranged in the sealing ring groove and sleeved on the first conductive probe, and the sealing ring is used to realize the sealing between the top plate and the cover plate.

[0015] Optionally, the bottom end of the top plate is provided with a first limiting groove, the top end of the bottom plate is provided with a second limiting groove, the first limiting groove and the second limiting groove are abutted to form a limiting groove, and the cold plate is arranged in the limiting groove.

[0016] Optionally, the diameter of the first flow-through hole is smaller than the diameter of the second flow-through hole.

[0017] Optionally, the top plate is further provided with a liquid inlet temperature measuring interface and a liquid outlet temperature measuring interface, the liquid inlet temperature measuring interface is in communication with the liquid inlet section, the liquid inlet temperature measuring interface is used for measuring the temperature of the working medium output by the liquid inlet section, the liquid outlet temperature measuring interface is in communication with the liquid outlet section, and the liquid outlet temperature measuring interface is used for measuring the temperature of the working medium output by the liquid outlet section.

[0018] Optionally, the top plate is further provided with a liquid inlet pressure measuring interface and a liquid outlet pressure measuring interface, the liquid inlet pressure measuring interface is in communication with the liquid inlet section, the liquid outlet pressure measuring interface is in communication with the liquid outlet section, and the liquid inlet pressure measuring interface and the liquid outlet pressure measuring interface are used for measuring the pressure difference between the working medium input by the liquid inlet section and the working medium output by the liquid outlet section.

[0019] The micro-channel heat exchange research device provided by the application is characterized in that: the working medium enters the liquid inlet section of the top plate, flows through the first flow-through hole, and then flows into the liquid inlet groove through the working medium inlet; then the working medium enters the micro-channel from the liquid inlet groove; in the micro-channel, the first simulated heat source directly contacts with the working medium and heats the working medium; because the first simulated heat source directly contacts with the working medium for heating, the heat generated by the first simulated heat source can be completely transferred to the wall surface of the micro-channel, greatly reducing the heat diffused to the area outside the micro-channel due to the solid heat conduction, reducing the error caused by the difficulty in quantitatively measuring this part of heat, thereby improving the accuracy of measuring temperature and more accurately measuring the heat flux density; the accuracy of the heat flux density is improved, and the error of the critical heat flux density prediction model is also reduced; the first temperature measuring structure is arranged to directly measure the wall surface temperature of the micro-channel, thereby reducing the calculation process of heat transfer from the wall surface outside the micro-channel to the wall surface of the micro-channel, reducing the error caused by lateral heat diffusion, and thereby improving the measurement accuracy of the local heat exchange coefficient. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained according to the structures shown in the drawings without creative labor for those skilled in the art.

[0021] Figure 1 It is an explosion schematic view of the micro-channel heat exchange research device in an embodiment;

[0022] Figure 2 It is a bottom view of the top plate of the micro-channel heat exchange research device in an embodiment;

[0023] Figure 3 It is a front view of the top plate of the micro-channel heat exchange research device in an embodiment;

[0024] Figure 4 Structure diagram of a base plate of a micro-channel heat exchange research device in an embodiment;

[0025] Figure 5 Structure diagram of a cover plate of a micro-channel heat exchange research device in an embodiment;

[0026] Figure 6 Structure diagram of a cold plate of a micro-channel heat exchange research device in an embodiment;

[0027] Figure 7 Top view of a cold plate of a micro-channel heat exchange research device in an embodiment;

[0028] Figure 8 Structure diagram of a base plate of a micro-channel heat exchange research device in an embodiment from another perspective;

[0029] Figure 9 Top view of a bottom plate of a micro-channel heat exchange research device in an embodiment

[0030] Figure 10 Structure diagram of a bottom plate of a micro-channel heat exchange research device in an embodiment.

[0031] Component names and serial numbers in the figure: 1, top plate; 11, liquid inlet section; 111, first liquid inlet section; 112, second liquid inlet section; 12, liquid outlet section; 121, first liquid outlet section; 122, second liquid outlet section; 13, first flow-through hole; 14, second flow-through hole; 15, first fixing hole; 16, sealing ring groove; 17, liquid inlet temperature measurement interface; 18, liquid outlet temperature measurement interface; 19, liquid inlet pressure measurement interface; 20, liquid outlet pressure measurement interface; 201, observation window; 2, bottom plate; 21, second fixing hole; 3, cold plate; 31, base plate; 311, groove; 312, liquid inlet groove; 313, micro-channel; 314, liquid outlet groove; 32, cover plate; 321, working medium inlet; 322, working medium outlet; 4, first temperature measurement structure; 41, temperature measurement section; 42, contact port; 5, first simulated heat source; 51, first conductive probe; 52, metal film; 6, bolt hole; 7, second simulated heat source; 71, metal layer; 72, second conductive probe; 8, second temperature measurement structure; 9, sealing ring; 10, limiting groove; 101, first limiting groove; 102, second limiting groove.

[0032] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0034] It should be noted that all the direction indications (such as up, down, left, right, front, back, and the like) in the embodiments of the present application are only used to explain the relative position relationship, movement condition and the like between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the direction indications also change accordingly.

[0035] In addition, the description of "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In addition, "and / or" throughout the text includes three schemes, for example, A and / or B includes A technical solution, B technical solution, and A and B simultaneously meet the technical solution; in addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of a person of ordinary skill in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the scope of protection claimed by the present application.

[0036] Reference Figures 1 to 7 A micro-channel heat exchange research device includes a top plate 1, a bottom plate 2 and a cold plate 3, the top plate 1 has a liquid inlet section 11 and a liquid outlet section 12, the top plate 1 is further provided with a first flow-through hole 13 and a second flow-through hole 14, the liquid inlet section 11 and the first flow-through hole 13 are communicated, the liquid outlet section 12 and the second flow-through hole 14 are communicated; the bottom plate 2 is arranged at the bottom end of the top plate 1; the cold plate 3 includes a base plate 31 and a cover plate 32, the cover plate 32 is arranged close to the top plate 1, the base plate 31 is arranged at the bottom end of the cover plate 32, the cover plate 32 is provided with a working medium inlet 321 and a working medium outlet 322, the working medium inlet 321 and the first flow-through hole 13 are communicated, the working medium outlet 322 and the second flow-through hole 14 are communicated, the base plate 31 is provided with a channel 311 close to one end of the cover plate 32, the channel 311 includes a liquid inlet channel 312, a micro-channel 313 and a liquid outlet channel 314 communicated in sequence, the liquid inlet channel 312 is communicated with the working medium inlet 321, the liquid outlet channel 314 is communicated with the working medium outlet 322, a first temperature measurement structure 4 is arranged at one end of the cover plate 32 close to the base plate 31, the first temperature measurement structure 4 is used for measuring the wall temperature of the micro-channel 313, a first simulated heat source 5 is used for directly contacting the working medium flowing in the micro-channel 313 and heating the working medium flowing in the micro-channel 313.

[0037] The application provides a micro-channel heat exchange research device. The working medium enters from the liquid inlet section 11 of the top plate 1, flows through the first flow-through hole 13, and then flows into the liquid inlet groove 312 through the working medium inlet 321. Then, the working medium enters the micro-channel 313 from the liquid inlet groove 312. In the micro-channel 313, the first simulated heat source 5 directly contacts the working medium and heats the working medium. Since the first simulated heat source 5 directly contacts the working medium for heating, the heat generated by the first simulated heat source 5 can be completely transferred to the wall surface of the micro-channel 313, greatly reducing the heat diffused to the area outside the micro-channel 313 due to the solid heat conduction effect, reducing the error caused by the difficulty in quantitatively measuring this part of heat, thereby improving the accuracy of measuring temperature and more accurately measuring heat flux density. The accuracy of the heat flux density is improved, and the error of the critical heat flux density prediction model is also reduced. The application directly measures the wall surface temperature of the micro-channel 313 by arranging the first temperature measuring structure 4, thereby reducing the calculation process of heat transfer from the wall surface outside the micro-channel 313 to the wall surface of the micro-channel 313, reducing the error caused by lateral heat diffusion, and thereby improving the measurement accuracy of the local heat exchange coefficient.

[0038] Specifically, the critical heat flux density prediction model is established by controlling different working medium flow rates and working medium inlet temperatures to measure the heat flux density at the critical state under different working conditions. The establishment of the critical heat flux density prediction model can facilitate the micro-channel heat exchange device to control the corresponding flow rate and working medium inlet temperature according to different critical heat flux densities in the working state, thereby preventing damage to the micro-channel heat exchange device.

[0039] Specifically, the top plate 1 is a cubic block made of transparent material. The transparent top plate 1 can realize observation of the flow pattern of the working medium in the micro-channel 313 from the top view angle. The specific material can be organic glass, borax glass, heat-resistant plastic, etc. with certain strength, transparent material, and capable of resisting temperatures above 120℃. The selection of the specific material is affected by the saturation temperature and pressure of the working medium.

[0040] Further, the top plate 1 is also provided with an observation window 201, which is arranged opposite to the micro-channel 313. The micro-channel 313 is the core heat exchange area, and the observation of the two-phase flow pattern of the working medium in the micro-channel 313 and the recording can be realized by arranging a high-speed camera above the observation window 201.

[0041] Specifically, two-phase flow pattern is a brief name of gas dispersed in liquid. Studies have shown that in the process of micro-channel flow boiling, various two-phase flow patterns such as bubble flow, slug flow, annular flow and the like will be formed in the micro-channel of tens to hundreds of microns. Through accurate judgment of the two-phase flow pattern under different boundary conditions (such as temperature, pressure, flow, heat flux density, etc.) and the structure parameters (such as size, shape, etc.) of the micro-channel and the internal relationship with the local heat transfer coefficient, an accurate critical heat flux density prediction model is established, which plays a crucial role in the design of the micro-channel heat exchange device.

[0042] Further, the critical heat flux density prediction model obtained through experimental research can be used in the micro-channel heat exchange device under actual working conditions, so that the micro-channel heat exchange device can control the working condition according to the critical heat flux density under the working condition.

[0043] In the embodiment, the top plate 1 and the bottom plate 2 are both provided with a plurality of bolt holes 6, and a plurality of bolts are correspondingly arranged in the plurality of bolt holes 6 to achieve the fastening connection of the top plate 1 and the bottom plate 2.

[0044] In the embodiment, the number of bolt holes 6 is 8.

[0045] Specifically, the substrate 31 is a silicon substrate 31, and the material of the cover plate 32 is transparent glass material, which can be infrared glass that can transmit medium and short wavelength red light, such as germanium glass, zinc selenide glass, calcium fluoride glass, zinc sulfide glass, etc. In this way, by setting the infrared thermometer, the temperature distribution in the micro-channel 313 can be directly observed through the observation window 201.

[0046] Specifically, the substrate 31 and the cover plate 32 are bonded to tightly fit the substrate 31 and the cover plate 32. The groove 311 on the substrate 31 is processed by photolithography technology, so that the shape and size of the etched micro-channel 313 can be accurately controlled.

[0047] Further, the bonding is to combine two pieces of surface-cleaning, atomically flat, homogenous or heterogeneous semiconductor materials under certain conditions through surface cleaning and activation treatment, van der Waals force, molecular force or even atomic force to make the wafer bonded into one. For the bonding of silicon and glass here, first, the material surface is bombarded by high-energy plasma to activate the material surface, and then the two parts are aligned and bonded with a certain clamping force. After the activation state of the surface stops, the two parts are tightly bonded and annealed to complete the bonding.

[0048] Further, the processing flow of the photolithography technology includes the following steps:

[0049] First, clean and pre-treat the substrate. For silicon wafers used for silicon substrate 31, deionized water or ethanol is usually used for cleaning and hexamethyl disilazane (HMDS) is used for pre-treatment, which makes the hydrophobic photoresist more easily attached to the surface of the silicon wafer;

[0050] Second, drop the appropriate amount of photoresist on the surface of the silicon wafer, use a spin coater to evenly attach the photoresist on the surface of the silicon wafer, and then put it into a vacuum drying oven at 95°C for 90 seconds as pre-exposure baking. For silicon wafers, the commonly used photoresist is AZ5214;

[0051] Third, cover the mask on the silicon wafer coated with photoresist and expose it. The common mask has two materials, film and chromium plate, which are processed with corresponding processing structure through holes, to ensure that light can and can only pass through the through hole, that is, the structure in the design will be exposed;

[0052] Fourth, develop using developer (AZ326), which decomposes the exposed part in the developer, and the unexposed part is not affected. After 45 seconds of development, wash and dry;

[0053] Fifth, etch the substrate after photoresist using a specific reagent, and the specific etching depth is controlled by controlling the amount of reagent. Sixth, after etching, ultrasonic cleaning in acetone for 15 minutes to remove surface contamination, and then use water to clean.

[0054] Specifically, the depth of the channel 311 is 50-500μm.

[0055] Specifically, the width of the liquid inlet groove 312 gradually increases along the flow direction of the working medium, so that the working medium flows into the microchannel 313 uniformly after flowing into the working medium inlet 321 through the liquid inlet groove 312.

[0056] The microchannel 313 is composed of a plurality of straight grooves, and the working medium uniformly flows into the plurality of straight grooves and is uniformly heated.

[0057] The width of the liquid outlet groove 314 gradually decreases along the flow direction of the working medium, which facilitates the working medium to flow out of the working medium outlet 322.

[0058] Further, the working medium undergoes boiling heat exchange in the microchannel 313, and the working medium is in liquid and gaseous states at the working medium outlet 322, therefore, a pump body is needed to provide power for the working medium to flow from the working medium outlet 322 to the liquid outlet section 12.

[0059] Reference Figure 1 and Figure 4The first simulated heat source 5 comprises a first conductive probe 51 and a metal film 52. The metal film 52 is embedded in the inner wall of the channel 311. The first conductive probe 51 is in contact with the metal film 52. The first conductive probe 51 is used to supply power to the metal film 52. The metal film 52 is used to generate heat to heat the working medium in the micro channel 313.

[0060] Specifically, when the first simulated heat source 5 is turned on, the two first conductive probes 51 are connected to the positive and negative poles of the power supply, respectively. The two first conductive probes 51 are in contact with the two ends of the metal film 52 to supply power to the metal film 52. The metal film 52 generates heat to heat the working medium in the micro channel 313.

[0061] Specifically, the material of the first conductive probe 51 is copper, which has good electrical conductivity.

[0062] Further, the first conductive probe 51 is provided with a protrusion. The protrusion is used to clamp and fix the first conductive probe 51 in the first fixed hole 15.

[0063] Specifically, the principle of heat generation of the metal film 52 is Joule heating effect. The heating power can be adjusted by controlling the current and voltage passing through the metal film 52.

[0064] Specifically, the metal film 52 is arranged on the bottom wall of the channel 311. The metal film 52 is arranged along the trajectory of the bottom wall of the micro channel 313 in a serpentine shape. In this way, the length of the metal film 52 can be lengthened and the width of the metal film 52 can be reduced, so that a metal film 52 with high resistance structure is obtained. The metal film 52 is respectively led to the liquid inlet groove 312 below the working medium inlet 321 and the liquid outlet groove 314 below the working medium outlet 322. The area of the metal film 52 in the liquid inlet groove 312 and the liquid outlet groove 314 is increased to facilitate contact with the first conductive probe 51.

[0065] Specifically, the metal film 52 is a Ti-Pt film. The formation process of the Ti-Pt film is as follows:

[0066] In order to ensure the flatness of the wall of the channel 311, an additional groove is etched at the corresponding position before magnetron sputtering. The sputtered metal will be filled into the groove. Since the connection effect between Pt and the silicon base is poor, a layer of Ti is sputtered between Pt and the silicon base to form a Ti-Pt film.

[0067] The working principle of the magnetron sputtering is that, under the action of an electric field, electrons collide with argon atoms during flying to the substrate, so that the argon atoms are ionized to generate Ar ions and new electrons; the new electrons fly to the substrate, and the Ar ions accelerate to the cathode target under the action of the electric field and bombard the surface of the target at high energy, so that the target material is sputtered. In the sputtered particles, neutral target atoms or molecules are deposited on the substrate to form a thin film. The specific processing steps are similar to the above-mentioned photolithography technology, except that the fifth step is changed to: using the magnetron sputtering technology to deposit the metal target material on the areas of the substrate that are not covered by the photoresist after photolithography, depositing a Ti layer first and then depositing a Pt layer, and the specific thickness of the thin film is controlled by controlling the power and time of sputtering.

[0068] Reference Figure 5 The first temperature measuring structure 4 includes a plurality of temperature measuring sections 41, which are arranged on the cover plate 32 at intervals along the flow direction of the working medium, so as to measure the wall surface temperature at different positions of the micro-channel 313, so as to obtain the local heat transfer coefficient at different positions of the micro-channel 313.

[0069] Specifically, the temperature measuring section 41 is composed of a Ti-Pt thin film sputtered on the surface of the cover plate 32, and the temperature measuring section 41 extends from the edge of the cover plate 32 to the middle of the cover plate 32. The temperature measuring section 41 at the edge of the cover plate 32 is provided with a contact port 42, the width of the contact port 42 is greater than the width of the temperature measuring section 41, and the area of the contact port is increased to facilitate connection with the wire. When the temperature measuring section 41 is connected with the wire, conductive silver adhesive is used to realize the connection and fixation between the temperature measuring section 41 and the wire.

[0070] Further, by measuring the resistance value of the Pt of the temperature measuring section 41, the temperature value at the measurement point is obtained by referring to the temperature-resistance curve of the Pt. The resistance of the Pt thin film changes sensitively and linearly, so the temperature measurement accuracy is high.

[0071] In this embodiment, the number of temperature measuring sections 41 is three.

[0072] Reference Figure 1 And Figure 8 The micro-channel heat exchange research device further includes a second simulated heat source 7 and a second temperature measuring structure 8. The second simulated heat source 7 is arranged at one end of the substrate 31 away from the cover plate 32, and is used to heat the outer wall surface of the channel 311 to heat the working medium flowing in the channel 311. The second temperature measuring structure 8 is arranged at one end of the substrate 31 away from the cover plate 32, and is used to measure the outer wall surface temperature of the channel 311.

[0073] Specifically, the second temperature measuring structure 8 is arranged below the micro-channel 313, and is used to measure the outer wall surface temperature of the micro-channel 313.

[0074] Specifically, the first simulated heat source 5 and the first temperature measuring structure 4 are used for the inner wall heating temperature measuring method, which has many processing steps, long process, high cost and high technical requirements. Therefore, when the temperature measuring precision requirement is not high, the second simulated heat source 7 and the second temperature measuring structure 8 can be used for the outer wall heating temperature measuring method.

[0075] Reference Figure 1 and Figures 8-9 The second simulated heat source 7 includes a metal layer 71 and a second conductive probe 72. The metal layer 71 is arranged at one end of the substrate 31 away from the cover plate 32. The number of the second conductive probe 72 is at least two. The second fixed hole 21 is also arranged on the bottom plate 2. The second conductive probe 72 corresponds to the second fixed hole 21 one by one. The second conductive probe 72 is arranged in the second fixed hole 21 and contacts the metal layer 71 to supply power to the metal layer 71. The metal layer 71 is used to supply power to the substrate 31 to generate heat to heat the working medium flowing in the micro-channel 313. Compared with the traditional method of introducing heating pieces and heating columns to heat the outer wall, the substrate 31 is used as a heat source in the present application, which can eliminate the contact thermal resistance caused by the additional heating materials, thereby realizing the high heat flux density and rapid heating of the substrate 31.

[0076] Specifically, the first simulated heat source 5 and the first temperature measuring structure 4 are used for the inner wall heating temperature measuring method, which has many processing steps, long process, high cost and high technical requirements. Therefore, when the temperature measuring precision requirement is not high, the second simulated heat source 7 and the second temperature measuring structure 8 can be used for the outer wall heating temperature measuring method, processing flow is relatively simple, and it is more universally applicable.

[0077] In the embodiment, the material of the substrate 31 is a phosphorus-doped silicon wafer, and the resistivity of the substrate 31 is 1-3 Ω / cm. The metal layer 71 is a solder layer.

[0078] Two thin and flat metal layers 71 are arranged at both ends of the substrate 31 as positive and negative electrodes when power is supplied. The two second conductive probes 72 contacting the metal layer 71 are connected to the power line to supply power to the metal layer 71, thereby supplying power to the substrate 31. Since the substrate 31 is a phosphorus-doped silicon wafer, it has good conductivity, and the heating of the substrate 31 can heat the micro-channel 313.

[0079] Specifically, the second temperature measuring structure 8 includes a plurality of thermocouples. The plurality of thermocouples are arranged on the substrate 31 along the flow direction of the working medium. Further, the thermocouples and the substrate 31 are fixedly connected by using a heat-conducting adhesive.

[0080] In the embodiment, the second conductive probe 72 has a first segment, a clamping portion and a second segment, the first segment is sleeved in the second segment, the clamping portion is arranged on the outer wall surface of the second segment, the clamping portion is used for clamping and fixing the second conductive probe 72 in the second fixing hole 21, the second segment is a hollow structure and is internally provided with a spring, and the spring is connected with the first segment, so that the first segment can move up and down in the interior of the second segment and cannot be separated from the second segment. When the cold plate 3 is assembled to the bottom plate 2, the cold plate 3 compresses the first segment, and then compresses the spring. The spring provides an upward force matched with the first conductive probe 51 to achieve the limiting support of the cold plate 3.

[0081] In the embodiment, the number of the second conductive probe 72 is 9, and the 9 second conductive probes 72 are arrayed and arranged in the second fixing hole 21. The 9 second conductive probes 72 and the plurality of first conductive probes 51 are matched to further achieve the soft support of the cold plate 3, reduce the requirement for the flatness of the cold plate 3, and simultaneously release the size limitation of the cold plate 3 to a certain extent, so as to support the cold plate 3 of various thicknesses and provide the possibility for the research of various channels 311.

[0082] Reference Figure 1 and Figure 2 The micro-channel heat exchange research device further comprises a sealing ring 9, and the top plate 1 is further provided with a sealing ring groove 16, the sealing ring groove 16 is coaxially arranged with the first fixing hole 15, the sealing ring 9 is arranged in the sealing ring groove 16 and is sleeved on the first conductive probe 51, and the sealing ring 9 is used for sealing between the top plate 1 and the cover plate 32.

[0083] Specifically, the sealing ring 9 is made of silica gel and has elasticity. Since the substrate 31 is made of silicon and has the characteristics of being hard and brittle, simple clamping may cause the cold plate 3 to deform or even break. The device uses the elastic sealing ring 9 and the first conductive probe 51 and the second conductive probe 72 internally provided with springs to cooperate with the top plate 1 and the cold plate 3, so as to achieve the limiting, fixing and soft support of the cold plate 3. The soft support reduces the requirement for the flatness of the contact surface of the cold plate 3, and simultaneously releases the size limitation of the cold plate 3 to a certain extent, so as to provide the possibility for the research of the cold plate 3 of various microstructures.

[0084] Specifically, the width of the sealing ring groove 16 is usually 1-2 mm, which is affected by the material elasticity of the sealing ring 9. The high-elasticity material can ensure the sealing effect under a smaller groove width size. The depth of the sealing ring groove 16 is usually 0.5 times the width of the sealing ring groove 16, and the inner diameter of the sealing ring groove 16 is greater than 0.5-2 mm compared with the first flow-through hole 13 or the second flow-through hole 14.

[0085] Further, the sealing ring 9 and the sealing ring groove 16 are matched, the thickness of the sealing ring 9 is 1.5-2.5 times of the depth of the sealing ring groove 16, thus, after the sealing ring 9 is assembled to the sealing ring groove 16, a part of the sealing ring 9 is still exposed outside the sealing ring groove 16, in this way, the sealing ring 9 can be closely attached to the top plate 1 and the cold plate 3, thus meeting the sealing requirement of the micro-channel heat exchange research device, and because of the elasticity, the cold plate 3 can be prevented from being damaged during sealing.

[0086] With reference to Figure 2 , Figure 9 and Figure 10 , the bottom end of the top plate 1 is provided with a first limiting groove 101, and the top end of the bottom plate 2 is provided with a second limiting groove 102; the first limiting groove 101 and the second limiting groove 102 are butted to form a limiting groove 10, and the cold plate 3 is arranged in the limiting groove 10.

[0087] Specifically, the shape of the limiting groove 10 is matched with the shape of the cold plate 3, and both are rectangular.

[0088] Further, the size of the limiting groove 10 is the same as that of the cold plate 3, so that the limiting groove 10 can limit and fix the cold plate 3 in the horizontal direction.

[0089] With reference to Figure 2 , the diameter of the first flow-through hole 13 is smaller than that of the second flow-through hole 14. In this way, the gaseous working medium can be discharged faster, thus reducing the phenomenon of channel blockage caused by a large amount of gas generated after the working medium in the cold plate 3 boils.

[0090] Specifically, the liquid inlet section 11 includes a first liquid inlet section 111 and a second liquid inlet section 112 connected in communication, and the second liquid inlet section 112 is also communicated with the first flow-through hole 13, the diameter of the first liquid inlet section 111 is larger than that of the second liquid inlet section 112, and the diameter of the second liquid inlet section 112 is the same as that of the first flow-through hole 13.

[0091] Further, the inlet of the first liquid inlet section 111 is provided with an internal thread, so as to be threadedly connected with the working medium circulating pipeline, and the diameter of the second liquid inlet section 112 is the same as that of the first flow-through hole 13, so as to facilitate the transition of working medium flow.

[0092] Still further, the diameter of the liquid inlet section 11 is related to the flow of the working medium.

[0093] Specifically, the liquid outlet section 12 includes a first liquid outlet section 121 and a second liquid outlet section 122, the first liquid outlet section 121 is communicated with the second flow-through hole 14, and the diameter of the first liquid outlet section 121 is the same as that of the second flow-through hole 14, so as to facilitate the transition of working medium flow, the diameter of the first liquid outlet section 121 is smaller than that of the second liquid outlet section 122, which is beneficial to the large amount of gaseous working medium to flow out, so as to avoid causing the blockage of working medium in the channel.

[0094] Reference Figure 2 The top plate 1 is further provided with a liquid inlet temperature measuring interface 17 and a liquid outlet temperature measuring interface, the liquid inlet temperature measuring interface 17 is communicated with the liquid inlet section 11, the liquid inlet temperature measuring interface 17 is used for measuring the temperature of the working medium output by the liquid inlet section 11, the liquid outlet temperature measuring interface is communicated with the liquid outlet section 12, and the liquid outlet temperature measuring interface is used for measuring the temperature of the working medium output by the liquid outlet section 12.

[0095] Specifically, the armored thermocouple is inserted into the liquid inlet temperature measuring interface 17 and the liquid outlet temperature measuring interface 18, that is, the temperature of the working medium flowing in the liquid inlet section 11 and the working medium flowing in the liquid outlet section 12 can be monitored in real time, the actual heat exchange amount of the working medium in the micro-channel heat exchange research device can be calculated, a research means for working medium flow and heat exchange analysis in the micro-channel is provided, and the heat flux density under different critical conditions can be measured under the conditions of different inlet temperatures and different flow rates, which provides conditions for the establishment of a critical heat flux density prediction model.

[0096] Reference Figure 2 The top plate 1 is further provided with a liquid inlet pressure measuring interface 19 and a liquid outlet pressure measuring interface 20, the liquid inlet pressure measuring interface 19 is communicated with the liquid inlet section 11, the liquid outlet pressure measuring interface 20 is communicated with the liquid outlet section 12, and the liquid inlet pressure measuring interface 19 and the liquid outlet pressure measuring interface 20 are used for measuring the pressure difference between the working medium input by the liquid inlet section 11 and the working medium output by the liquid outlet section 12.

[0097] Specifically, the liquid inlet pressure measuring interface 19 and the liquid outlet pressure measuring interface 20 are respectively used for connecting two pressure measuring sections of a differential pressure transmitter, so as to realize real-time monitoring of the pressure difference between the working medium flowing in the liquid inlet section 11 and the working medium flowing in the liquid outlet section 12, so as to obtain the pressure loss of the working medium in the micro-channel heat exchange research device, and a research means for working medium flow and heat exchange characteristics in the micro-channel is provided.

[0098] A use method of the micro-channel heat exchange research device: connecting the working medium circulation pipeline of the experimental system to the liquid inlet section 11 and the liquid outlet section 12 respectively, inserting the armored thermocouple into the liquid inlet temperature interface and the liquid outlet temperature measuring interface 18, connecting the two pressure measuring sections of the differential pressure transmitter to the liquid outlet pressure measuring interface 20 and the liquid inlet pressure measuring interface 19, erecting the high-speed camera above the experimental device and aligning the observation window, if the silicon-based channel 311 cold plate 3 is bonded with the substrate 31 by using infrared glass at this time, an infrared temperature measuring instrument can be used for synchronous observation.

[0099] The working substance is pumped from the top plate 1 working substance liquid inlet section 11 using a power source, and the working substance enters the cold plate 3 after passing through the top plate 1, and then flows out from the liquid outlet section 12 after passing through the top plate 1 again. The input power to the experimental object is controlled by adjusting the voltage of the power supply to control the current output on the first conductive probe 51 or the second conductive probe 72. At this time, the high-speed camera shoots the working substance flow pattern in the channel 311 from the overhead perspective through the observation window, and the infrared temperature measuring instrument directly observes the temperature distribution of the silicon-based channel 311 cold plate 3 heating area through the observation window. The temperature and pressure difference of the working substance at the liquid inlet section 11 and the liquid outlet section 12 of the working substance, the inner wall temperature of the cold plate 3 and the outer wall temperature of the cold plate 3, the above real-time data can be collected by the data acquisition device and integrated with the state of the working substance in the microchannel 313 shot by the high-speed camera, to obtain the relationship between the working substance heat exchange and flow characteristics, and to carry out the working substance boiling heat transfer characteristic research of the microchannel heat exchange research device of the application.

[0100] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation made under the inventive concept of the present application, using the content of the present application specification and drawings, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A microchannel heat exchange research device, characterized in that, include: The top plate has a liquid inlet section and a liquid outlet section. The top plate is also provided with a first flow hole and a second flow hole. The liquid inlet section is connected to the first flow hole, and the liquid outlet section is connected to the second flow hole. A base plate is disposed at the bottom end of the top plate; A cold plate, comprising a substrate and a cover plate, wherein the cover plate is disposed near the top plate, the substrate is disposed at the bottom end of the cover plate, the cover plate is provided with a working fluid inlet and a working fluid outlet, the working fluid inlet is connected to a first flow hole, the working fluid outlet is connected to a second flow hole, and a channel is provided at one end of the substrate near the cover plate, the channel comprising a liquid inlet groove, a microchannel and a liquid outlet groove connected in sequence, the liquid inlet groove being connected to the working fluid inlet and the liquid outlet groove being connected to the working fluid outlet; A first temperature measuring structure is disposed at one end of the cover plate near the substrate, and the first temperature measuring structure is used to measure the wall temperature of the microchannel; as well as A first simulated heat source is used to directly contact the working fluid flowing in the microchannel and to heat the working fluid flowing in the microchannel. The first simulated heat source includes a first conductive probe and a metal film. The metal film is embedded in the inner wall of the channel. There are two first conductive probes. The top plate is provided with two first fixing holes. The two first fixing holes are coaxially arranged with the first flow hole and the second flow hole, respectively. The first conductive probes are inserted into the first fixing holes one by one and contact the metal film to supply power to the metal film. The metal film is used to generate heat to heat the working fluid flowing in the microchannel.

2. The microchannel heat exchange research device according to claim 1, characterized in that, The first temperature measuring structure includes multiple temperature measuring segments, which are spaced apart on the cover plate along the flow direction of the working fluid.

3. The microchannel heat exchange research device according to claim 1, characterized in that, The microchannel heat exchange research device further includes a second simulated heat source and a second temperature measuring structure. The second simulated heat source is disposed at the end of the substrate away from the cover plate and is used to heat the outer wall surface of the channel to heat the working fluid flowing in the channel. The second temperature measuring structure is disposed at the end of the substrate away from the cover plate and is used to measure the temperature of the outer wall surface of the channel.

4. The microchannel heat exchange research device according to claim 3, characterized in that, The second simulated heat source includes a metal layer and a second conductive probe. The metal layer is disposed at the end of the substrate away from the cover plate. There are at least two second conductive probes. The base plate also has a second fixing hole. The second conductive probe corresponds to the second fixing hole one by one. The second conductive probe passes through the second fixing hole and contacts the metal layer to supply power to the metal layer. The metal layer is used to supply power to the substrate so that the substrate generates heat to heat the working fluid flowing in the microchannel.

5. The microchannel heat exchange research device according to claim 1, characterized in that, The microchannel heat exchange research device also includes a sealing ring, and a sealing ring groove is provided on the top plate. The sealing ring groove is coaxially arranged with the first fixing hole. The sealing ring is disposed in the sealing ring groove and sleeved on the first conductive probe. The sealing ring is used to achieve a seal between the top plate and the cover plate.

6. The microchannel heat exchange research device according to claim 1, characterized in that, The top plate has a first limiting groove at its bottom end and the bottom plate has a second limiting groove at its top end; the first limiting groove and the second limiting groove are joined together to form a limiting groove, and the cold plate is disposed in the limiting groove.

7. The microchannel heat exchange research device according to claim 1, characterized in that, The diameter of the first flow hole is smaller than the diameter of the second flow hole.

8. The microchannel heat exchange research device according to claim 1, characterized in that, The top plate is also provided with an inlet temperature measurement interface and an outlet temperature measurement interface. The inlet temperature measurement interface is connected to the inlet section and is used to measure the temperature of the working fluid output from the inlet section. The outlet temperature measurement interface is connected to the outlet section and is used to measure the temperature of the working fluid output from the outlet section.

9. The microchannel heat exchange research device according to claim 1, characterized in that, The top plate is also provided with an inlet pressure measurement interface and an outlet pressure measurement interface. The inlet pressure measurement interface is connected to the inlet section, and the outlet pressure measurement interface is connected to the outlet section. The inlet pressure measurement interface and the outlet pressure measurement interface are used to measure the pressure difference between the working medium input into the inlet section and the working medium output from the outlet section.

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