Channel heat exchange method, heat exchange and heat dissipation system and computer readable storage medium

Abstract

The invention relates to the technical field of heat exchange, in particular to a channel heat exchange method, a heat exchange and heat dissipation system and a computer readable storage medium. The channel heat exchange method comprises the steps that a preset electric field is controlled to be applied to an electrode medium located in a heat exchange channel; wherein the heat exchange channel is used for flowing a nanofluid; controlling to apply a preset magnetic field to a magnet medium outside the heat exchange channel; the magnet media are arranged on the two opposite sides of the exterior of the heat exchange channel. And the nanofluid with the supercooling degree is introduced into the heat exchange channel for heat absorption. By adopting the method, the heat exchange performance can be enhanced, so that the heat exchange efficiency is improved, and the heat dissipation effect is optimized.

Description

Technical Field

[0001] The present application relates to the field of heat exchange technology, and in particular to a channel heat exchange method, a heat exchange system, a heat dissipation system, and a computer-readable storage medium. Background Art

[0002] In recent years, with the continuous development of communication technology and micro-electromechanical technology, electronic devices have been developing towards miniaturization and integration in the process of modern industrialization, driving the pursuit of high heat transfer performance while taking into account the compactness of component structure. With the improvement of integration, the heat flux density of equipment has increased rapidly, but electronic devices need to operate efficiently and stably in a system with suitable temperature. Traditional single-phase heat exchange technologies such as water cooling and forced air cooling are gradually unable to meet the growing heat exchange demand due to their low heat transfer efficiency and high energy loss rate. Two-phase heat exchange technologies such as flow boiling with higher heat transfer effect have emerged.

[0003] In two-phase heat exchange, the heat exchange medium used for cooling can not only use sensible heat to exchange heat with the heat exchanger equipment, but also use latent heat to enable the heat exchanger equipment to discharge more heat while maintaining a lower temperature. At present, the heat exchange efficiency of two-phase heat exchange still needs to be improved. Summary of the invention

[0004] Based on this, it is necessary to provide a channel heat exchange method, a heat exchange system, a heat dissipation system and a computer-readable storage medium to address the above technical problems, which can enhance the heat exchange performance to improve the heat exchange efficiency, thereby facilitating the optimization of the heat dissipation effect.

[0005] On the one hand, a channel heat exchange method is provided, which includes: controlling the application of a preset electric field to an electrode medium located in a heat exchange channel; wherein the heat exchange channel is used to flow a nanofluid; controlling the application of a preset magnetic field to a magnetic medium located outside the heat exchange channel; wherein the magnetic medium is arranged on two opposite sides of the outside of the heat exchange channel; and passing a nanofluid with a degree of supercooling into the heat exchange channel for heat absorption.

[0006] In one embodiment of the present application, the channel heat exchange method also includes: using a preset heat exchange analysis method to analyze the heat exchange parameters of the heat exchange channel under different scenario conditions; wherein, under different scenario conditions, the experimental electric field and / or experimental magnetic field applied to the heat exchange channel are different; and selecting a preset electric field and a preset magnetic field based on the heat exchange parameters under different scenario conditions.

[0007] In one embodiment of the present application, the heat exchange parameters include wall superheat; analyzing the wall superheat of the heat exchange channel includes: obtaining the thermal efficiency, input thermal power and target wall area of ​​the heat exchange channel; wherein the target wall is the side wall through which the nanofluid can flow; weighting the input thermal power using the thermal efficiency, and taking the ratio of the weighted result to the target wall area as the heat flux density; evaluating the target wall temperature of the heat exchange channel using the heat flux density, and taking the difference between the target wall temperature and the saturation temperature of the heat exchange medium as the wall superheat.

[0008] In one embodiment of the present application, obtaining the thermal efficiency of the heat exchange channel includes: obtaining the mass flow rate of the heat exchange medium; wherein the mass flow rate of the heat exchange medium is associated with the mass flow rate of the nanofluid in a single heat exchange channel; obtaining the difference between the cross-sectional areas of the single heat exchange channel and the electrode medium, and weighting the difference in cross-sectional areas using the number of heat exchange channels to obtain a first factor; wherein the cross-sectional area is the orthographic projection area of ​​the cross section perpendicular to the flow direction of the nanofluid; and taking the ratio between the mass flow rate of the heat exchange medium and the first factor as the thermal efficiency of the heat exchange channel.

[0009] In one embodiment of the present application, the heat exchange parameters include a channel convection heat transfer coefficient; analyzing the channel convection heat transfer coefficient of the heat exchange channel includes: weighting the width factor using the heat flux density of the heat exchange channel to obtain a second factor; wherein the width factor is associated with the fin width and the width of a single heat exchange channel; obtaining a temperature difference factor and a rib parameter factor, and weighting the rib parameter factor using the temperature difference factor to obtain a third factor; and using the ratio of the second factor to the third factor as the channel convection heat transfer coefficient.

[0010] In one embodiment of the present application, the temperature difference factor is associated with the target wall temperature of the heat exchange channel and the temperature of the heat exchange medium in the heat exchange channel, and the rib parameter factor is associated with the fin width, the rib efficiency and the height of a single heat exchange channel; obtaining the target wall temperature includes: taking the ratio of a preset wall temperature factor to a temperature parameter as the target wall temperature; wherein the preset wall is opposite to the target wall, the preset wall temperature factor is associated with the temperature of the sensed preset wall, the distance between the temperature sensing component and the target wall, the temperature parameter is associated with the heat flux density and the thermal conductivity of the material inside the heat exchange channel; and / or, obtaining the rib efficiency includes: obtaining the rib parameters and the height of a single heat exchange channel, and evaluating the rib efficiency based on the rib parameters and the height of the single heat exchange channel.

[0011] On the other hand, a heat exchange system is provided, which includes: a heat exchange channel, a preheating component, an electrode medium, a magnetic medium and a control module; the heat exchange channel is used to circulate the nanofluid; the preheating component is arranged on the upstream side of the heat exchange channel, and is used to heat the nanofluid; the electrode medium is arranged in the heat exchange channel; the magnetic medium is arranged on two opposite sides of the outside of the heat exchange channel; and the control module is used to implement the channel heat exchange method as in any of the above embodiments.

[0012] In one embodiment of the present application, the heat exchange system also includes: a liquid storage component, a condensation component, a drive component and a parameter sensing component; the liquid storage component is used to store nanofluid; the condensation component is arranged on the downstream side of the heat exchange channel, and is used to condense the nanofluid flowing out of the heat exchange channel; the drive component is used to drive the nanofluid to circulate within the self-heat exchange system; the parameter sensing component is used to sense the operating parameters required for the preset heat exchange analysis method.

[0013] On the other hand, a heat dissipation system is provided, which includes: a heat exchange system as in any of the above embodiments and a heat dissipation shell; the heat exchange system is arranged inside the heat dissipation shell.

[0014] On the other hand, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented: controlling the application of a preset electric field to an electrode medium located in a heat exchange channel; wherein the heat exchange channel is used to flow nanofluid; controlling the application of a preset magnetic field to a magnetic medium located outside the heat exchange channel; wherein the magnetic medium is arranged on two opposite sides of the outside of the heat exchange channel; and passing a nanofluid with a degree of supercooling into the heat exchange channel for heat absorption.

[0015] In the above-mentioned channel heat exchange method, heat exchange system, heat dissipation system and computer-readable storage medium, nanofluid is used in the heat exchange channel. Compared with the heat exchange channel of a conventional heat exchange system, the heat exchange channel in the present application is smaller in size and can generally be considered as a small channel. In the present application, nanoparticles are added to the refrigerant fluid to improve the heat transfer effect of the refrigerant. At the same time, an electric field and a magnetic field environment are also applied to the heat exchange channel to further enhance the heat transfer effect. Under the same conditions, the nanofluid in the present application can absorb more heat to enhance the heat exchange performance, which can help improve the heat exchange efficiency and thus help optimize the heat dissipation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of a flow chart of an embodiment of the channel heat exchange method of the present application;

[0017] Figure 2 It is a structural schematic diagram of an embodiment of the heat exchange system of the present application;

[0018] Figure 3 is a structural schematic diagram of another embodiment of the heat exchange system of the present application;

[0019] Figure 4 It is a structural schematic diagram of an embodiment of a heat exchange channel of the present application;

[0020] Figure 5 This is a schematic diagram of a process flow of an embodiment of a preset heat exchange analysis of the present application;

[0021] Figure 6It is a schematic diagram of a wall superheat diagram of an embodiment of a preset heat exchange analysis of the present application;

[0022] Figure 7 It is a schematic diagram of a channel convection heat transfer coefficient chart of an embodiment of a preset heat exchange analysis of the present application;

[0023] Figure 8 It is a structural schematic diagram of an embodiment of the heat dissipation system of the present application;

[0024] Fig. 9 It is a structural diagram of an embodiment of a computer device of the present application. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0026] There is a lack of experimental research on the effect of electric fields on the flow boiling heat transfer of magnetic nanofluids in the relevant technology. In view of this, there is some controversy as to whether electric fields can necessarily enhance heat transfer, and the specific mechanism of action is still missing. Research on the effect of magnetic fields on magnetic nanofluids is mainly concentrated in conventional scale channels, and whether nanofluids can enhance heat transfer after applying magnetic excitation in micro channels also requires experimental exploration. Different factors such as the size, type, and direction of the magnetic excitation have different effects on the enhancement of magnetic nanofluids.

[0027] In order to solve the technical problem that the heat exchange efficiency of two-phase heat exchange in the related art needs to be improved, the present application provides a channel heat exchange method, a heat exchange system, a heat dissipation system and a computer-readable storage medium. The channel heat exchange method includes: controlling the application of a preset electric field to an electrode medium located in a heat exchange channel; wherein the heat exchange channel is used to flow a nanofluid; controlling the application of a preset magnetic field to a magnetic medium located outside the heat exchange channel; wherein the magnetic medium is arranged on two opposite sides of the outside of the heat exchange channel; and passing a nanofluid with a supercooling degree into the heat exchange channel for heat absorption. The specific structure and detailed working principle of the present application are described below by way of example.

[0028] See also Figure 1 , Figure 1 It is a flow chart of an embodiment of the channel heat exchange method of the present application.

[0029] S101: Controlling the application of a preset electric field to an electrode medium located in a heat exchange channel; wherein the heat exchange channel is used for flowing nanofluid.

[0030] In this embodiment, an electrode medium may be provided in the heat exchange channel to apply an electric field to the heat exchange channel. The heat exchange channel can flow nanofluids. That is, when the nanofluids flow through the heat exchange channel, they can absorb heat in the heat exchange channel and convert into a gas state, thereby achieving heat exchange.

[0031] S102: Controlling the application of a preset magnetic field to the magnetic medium located outside the heat exchange channel; wherein the magnetic medium is disposed on two opposite sides of the outside of the heat exchange channel.

[0032] In this embodiment, a magnetic medium may be disposed outside the heat exchange channel to apply a preset magnetic field to the magnetic medium located on two opposite sides, so that the heat exchange channel is in a magnetic field environment of the preset magnetic field.

[0033] Optionally, the magnetic medium can be disposed at one end of the heat exchange channel close to the upstream side, or at one end of the heat exchange channel close to the downstream side, or at the middle section of the heat exchange channel, which is not limited here.

[0034] S103: Passing the nanofluid with supercooling into the heat exchange channel to absorb heat.

[0035] In this embodiment, the supercooling degree means that the temperature of the nanofluid has not yet reached the critical point temperature for conversion from liquid to gas, and the critical point temperature can be considered as the saturation temperature of the heat exchange medium containing the nanofluid. The nanofluid flowing into the heat exchange channel is a liquid heat exchange medium with supercooling degree, and can undergo phase change and be converted into gas-liquid two-phase flow by absorbing heat in the heat exchange channel under the synergistic field. Among them, the synergistic field means that the preset electric field and the preset magnetic field are applied at the same time.

[0036] In this embodiment, nanofluid is used in the heat exchange channel. Compared with the heat exchange channel of the conventional heat exchange system, the heat exchange channel in this embodiment is smaller in size and can generally be considered as a small channel. In addition, nanoparticles are added to the refrigerant in this embodiment to improve the heat transfer effect of the refrigerant. At the same time, an electric field and a magnetic field environment are also applied to the heat exchange channel to further enhance the heat transfer effect. Under the same conditions, the nanofluid of this application can absorb more heat to enhance the heat exchange performance, which can help improve the heat exchange efficiency and thus help optimize the heat dissipation effect.

[0037] See also Figure 2 , Figure 2 It is a structural schematic diagram of an embodiment of the heat exchange system of the present application.

[0038] In one embodiment, the heat exchange system may include a heat exchange channel 11 , a preheating component 12 , an electrode medium 13 , a magnet medium 14 and a control module 15 .

[0039] The heat exchange channel is used to circulate the nanofluid. The preheating component is arranged at the upstream side of the heat exchange channel to heat the nanofluid. The electrode medium is arranged in the heat exchange channel. The magnetic medium is arranged on two opposite sides of the heat exchange channel. The control module is used to implement the channel heat exchange method in any of the above embodiments.

[0040] Optionally, the hydraulic diameter D h Divide into microchannels, microchannels and regular channels. h Channels <200 μm are defined as microchannels, D h Channels with a size of >3 mm are classified as conventional channels, and channels with a size between 200 μm and 3 mm are classified as micro channels. In this embodiment, channel heat exchange design can be performed for micro channels.

[0041] For example, a heat exchange medium may flow in the heat exchange channel, and the heat exchange medium may include pure refrigerant ethylene dichlorofluoride (R141b) and a magnetic nanofluid. The magnetic nanofluid may be configured with R141b as a base fluid and magnetic nanoparticles Fe3O4 (ferroferric oxide) added to form a nanofluid with a mass concentration of 0.1%.

[0042] Specifically, the physical properties of R141b and nanoparticles are shown in Tables 1 and 2.

[0043] Table 1 Physical properties of R141b

[0044]

[0045] Table 2 Physical properties of nanoparticles

[0046]

[0047] The specific steps of configuration can be as follows: the nanofluid can be configured by a "two-step method", and an appropriate amount of non-ionic surfactant "sorbitan oleate (Span 80)" can be added, and it is subjected to 1h (hour) oscillation treatment in an ultrasonic cleaning machine. During the oscillation process, the refrigerant needs to be kept below the saturation temperature to obtain a relatively stable nanofluid. After the configuration is completed, the nanofluid is allowed to stand, and the nanofluid exhibits relatively excellent colloidal stability without visible sedimentation.

[0048] After the nanofluid is configured, the physical properties of the heat exchange medium will change to a certain extent due to the addition of nanoparticles. The mass fraction of the nanofluid configured in this embodiment is 0.1%, which belongs to a nanofluid with a relatively low concentration. Therefore, the various physical properties can be determined by theoretical calculation methods. The values ​​of various physical properties are calculated according to formulas 1-1 to 1-5 as shown in Table 3:

[0049]

[0050] Where w is the mass fraction; ρ is the density, kg / m 3 ; is the volume fraction, C is the specific heat capacity at constant pressure, the unit is kJ / (kg·K); λ is the thermal conductivity, the unit is W / (m·K); μ is the dynamic viscosity, the unit is Pa·s (Pascal second); in the subscripts of Formulas 1-1 to 1-5, nf, p, and bf represent nanofluid, nanoparticles, and pure refrigerant, respectively.

[0051] Table 3 Physical properties of nanofluids

[0052]

[0053] Please refer to Figures 2 to 3 , Figure 3 It is a schematic diagram of the nanofluid flow path of an embodiment of the heat exchange system of the present application.

[0054] In one embodiment, the heat exchange system may further include a liquid storage component, a condensation component, a drive component, and a parameter sensing component. The liquid storage component is used to store the nanofluid. The condensation component is arranged at the downstream side of the heat exchange channel, and is used to condense the nanofluid flowing out of the heat exchange channel. The drive component is used to drive the nanofluid to circulate in the heat exchange system. The parameter sensing component is used to sense the operating parameters required by the preset heat exchange analysis method.

[0055] Specifically, liquid nanofluids and other heat exchange media can flow out of the liquid storage component through the drive of a driving component such as a pump, enter the preheating component through a flow sensor such as a flow meter and a mass flow sensor such as a mass flow meter, and heat the heat exchange media through the preheating component to reach the saturated liquid temperature before entering the heat exchange channel for heat exchange. The gaseous heat exchange media flowing out of the heat exchange channel flows through a condensation component such as a water cooling device for cooling. The cooled liquid heat exchange media passes through a filtering component such as a filter, and the filtered heat exchange media returns to the liquid storage component to complete a complete working medium cycle.

[0056] Or, you can Figure 3 As shown in the example, the filter assembly can be arranged on the downstream side of the liquid storage assembly. In this way, the heat exchange medium with a certain degree of supercooling is pulled out of the liquid storage assembly through the driving assembly, and the heat exchange medium flows into the preheating assembly through the filter assembly, the flow sensor and the mass flow sensor, and enters the heat exchange channel for heat exchange after being heated to an appropriate temperature, so as to complete the flow boiling heat exchange process in the heat exchange channel. Then, the heat exchange medium in a gas-liquid mixed state flows into the condensation assembly through the pipeline for cooling, and the gaseous heat exchange medium changes into a liquid heat exchange medium, and re-enters the liquid storage assembly after being cooled to an appropriate temperature to complete a complete medium cycle, which is conducive to further improving the sensing accuracy of the heat exchange medium flow rate and mass flow rate.

[0057] See also Figure 4 , Figure 4 It is a structural schematic diagram of an embodiment of a heat exchange channel of the present application.

[0058] In one embodiment, the number of heat exchange channels can be multiple. That is, the heat exchange system can include multiple single heat exchange channels connected in parallel. For example, it can be composed of 9 heat exchange channels with a length of L = 250 mm (millimeter), a width of d = 2 mm, and a height of h = 2 mm connected in parallel.

[0059] The heat exchange channel may include an inlet pressure measuring hole 21, an outlet pressure measuring hole 22, an inlet temperature measuring hole 23, an outlet temperature measuring hole 24 and a wall temperature measuring hole 25. The inlet refers to the opening where the heat exchange medium flows into the heat exchange channel, and the outlet refers to the opening where the heat exchange medium flows out of the heat exchange channel.

[0060] For the specific definition of the heat exchange system, please refer to the definition of the channel heat exchange method in the context, which will not be repeated here. Each module in the above heat exchange system can be implemented in whole or in part by software, hardware and a combination thereof. The above modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0061] See also Figure 5 , Figure 5 It is a flow chart of an embodiment of the preset heat exchange analysis of the present application.

[0062] S201: Arrange electric field and magnetic field.

[0063] In this embodiment, an electrode medium, such as a copper wire with a diameter of 0.1 mm, is arranged directly above the center of each heat exchange channel. It is connected to the positive pole of a DC power supply as the positive electrode of the heat exchange channel and the voltage of the DC power supply is adjusted to a preset voltage, such as 200V (volts). The electrode medium can be close to the quartz glass, and any place in contact with the metal aluminum shell can be insulated. In this way, electrode media such as copper wire can be used as the positive pole of an external electric field, and the aluminum wall is connected to the ground wire to apply a preset electric field. That is, copper wire is arranged as an electrode medium in each heat exchange channel, and each electrode medium is connected to the positive pole of a DC regulated power supply to provide an electric field interference environment required for heat exchange channel research.

[0064] The preset magnetic field environment can be realized with the assistance of magnetic media, and the magnetic media can be placed in a preset magnetic field strength environment. For example, two pieces of NdFeB (N50) permanent magnets of the same size and a magnetic field strength of 350 mT (milli-Tesla) can be used as magnetic media. The two pieces can be placed on both sides of the channel in an arrangement of opposite poles, and the pair of magnetic blocks can be fixed in the middle section of the channel.

[0065] S202: Collect temperature parameter combinations and flow parameter combinations.

[0066] In this embodiment, a plurality of temperature sensing components may be provided in the heat exchange channel to collect the temperature parameter combination. For example, 10 K-type thermocouples may be provided in the heat exchange channel to measure the inlet and outlet temperature signals of the heat exchange equipment and the base temperature, of which 8 thermocouples are placed on the base substrate and the other 2 are placed on the microchannel inlet and outlet. The sampling time may be set to 420s, and the sampling frequency may be set to collect 30 temperature values ​​in 1 second, and the measurement error range may be within ±0.1K (Kelvin temperature). Among them, the heat exchange channel may be fixed vertically behind the base of the experimental bench and wrapped with heat insulation cotton to reduce heat loss, thereby facilitating the reliability of the results of the preset heat exchange analysis.

[0067] S203: Execute a preset heat exchange analysis using a temperature parameter combination and a flow parameter combination.

[0068] In this embodiment, a preset heat exchange analysis method can be used to analyze the heat exchange parameters of the heat exchange channel under different scene conditions; wherein, under different scene conditions, the experimental electric field and / or experimental magnetic field applied to the heat exchange channel are different; and the preset electric field and the preset magnetic field are selected based on the heat exchange parameters under different scene conditions. The details will be explained later.

[0069] S204: Perform data processing on the analysis.

[0070] In this embodiment, corresponding charts can be drawn based on the results of each experiment during the analysis process to achieve intuitive visualization of the analysis results, and then the heat exchange performance under different scenario conditions can be observed through the drawn charts to select the preset voltage and preset magnetic field strength under the collaborative field to achieve the collaborative field construction of the preset electric field and the preset magnetic field.

[0071] The specific analysis method of the heat exchange analysis method preset in this application is described below with examples.

[0072] The heat transfer parameters may include wall superheat and / or channel convection heat transfer coefficient.

[0073] When the heat exchange parameters include wall superheat, the specific method of analyzing the heat flux density of the heat exchange channel can be as follows: the thermal efficiency, input heat power and target wall area of ​​the heat exchange channel can be obtained. Among them, the target wall is the side wall through which the nanofluid can flow. The input heat power is weighted by the thermal efficiency, and the ratio of the weighted result to the target wall area is used as the heat flux density. The heat flux density can be used to evaluate the target wall temperature of the heat exchange channel, and the difference between the target wall temperature and the saturation temperature of the heat exchange medium is used as the wall superheat.

[0074] Optionally, the mass flow rate of the heat exchange medium can be obtained. The mass flow rate of the heat exchange medium is associated with the mass flow rate of the nanofluid in a single heat exchange channel. The difference between the cross-sectional areas of the single heat exchange channel and the electrode medium is obtained, and the difference in cross-sectional areas is weighted by the number of heat exchange channels to obtain a first factor. The cross-sectional area is the orthographic projection area of ​​the cross section perpendicular to the flow direction of the nanofluid. The ratio between the mass flow rate of the heat exchange medium and the first factor is used as the thermal efficiency of the heat exchange channel.

[0075] In this embodiment, it is taken into consideration that although the heat exchange channel is insulated with thermal insulation cotton, it still cannot guarantee that the heat of the heating plate can be completely transferred to the flowing heat exchange medium, and there is a certain amount of heat loss. Therefore, when calculating the heat flux density, its thermal efficiency is calculated.

[0076] The following is an example of the process of obtaining heat flux density through the formula:

[0077]

[0078] Q f =GC p,l (T in -T out ) Formula 2-2

[0079] P=UI Formula 2-3

[0080]

[0081] Where, M is the total mass flow rate of the working fluid, in kg / s (kilograms per second); N ch is the number of channels, that is, the number of heat exchange channels; A ch is the cross-sectional area of ​​a single heat exchange channel, in m 2 (square meters); A bw is the cross-sectional area of ​​the electrode medium in the channel, in m 2 Among them, A ch =W ch ×H ch , A bw =π(d cw )2 / 4,W ch and H ch are the length and height of a single channel, d cw is the diameter of the copper wire; C p,l is the specific heat capacity of the liquid phase at constant pressure, with the unit of kJ / (kg·k) (kilojoule per kilogram Kelvin); T in and T out are the temperatures of the liquid heat exchange medium at the inlet and outlet of the heat exchange channel, respectively, in K (K); G is the mass flow rate in a single heat exchange channel; Q fis the single-phase heat flux density; β is the thermal efficiency; P is the input thermal power; U is the voltage, the unit is V; I is the current, the unit is A (ampere); β is the thermal efficiency, P is the input thermal power, the unit is W (watt); A base is the area of ​​the bottom wall of the channel, which is the target wall, in m 2 . A base =W tw ×W tl , W tw and W tl are the width and length of the channel respectively; q is the heat flux density.

[0082] When the heat exchange parameters include the channel convection heat transfer coefficient, the specific method of analyzing the channel convection heat transfer coefficient of the heat exchange channel can be as follows: the width factor can be weighted by the heat flux density of the heat exchange channel to obtain the second factor. Among them, the width factor is associated with the fin width and the width of a single heat exchange channel. The temperature difference factor and the rib parameter factor are obtained, and the rib parameter factor is weighted by the temperature difference factor to obtain the third factor. The ratio of the second factor to the third factor is used as the channel convection heat transfer coefficient.

[0083] Optionally, the temperature difference factor is associated with the target wall temperature of the heat exchange channel and the temperature of the heat exchange medium in the heat exchange channel, and the fin parameter factor is associated with the fin width, fin efficiency and height of a single heat exchange channel.

[0084] In this way, the ratio of the preset wall temperature factor and the temperature parameter can be used as the target wall temperature; wherein the preset wall is opposite to the target wall, the preset wall temperature factor is associated with the temperature sensed by the preset wall, and the distance between the temperature sensing component and the target wall, the temperature parameter is associated with the heat flux density and the thermal conductivity of the material inside the heat exchange channel to obtain the target wall temperature.

[0085] And / or, the rib parameters and the height of a single heat exchange channel may be obtained, and the rib efficiency may be evaluated based on the rib parameters and the height of the single heat exchange channel to obtain the rib efficiency.

[0086] The following is an example of the process of obtaining the channel convection heat transfer coefficient through the formula:

[0087]

[0088]

[0089] T f =T sat Formula 2-11

[0090] Among them, T f is the temperature of the heat transfer medium in the heat transfer channel; T satis the saturation temperature of the heat exchange medium; z is the length of the single-phase section inside the heat exchange channel; d1 is the distance between the upper sensor temperature measuring hole and the bottom wall of the channel, that is, the distance between the temperature sensing component and the target wall, for example, d1 can be 18mm, etc.; T w is the target wall temperature; m is the rib parameter; η is the rib efficiency; W fin W is the fin width, in m (meter); ch is the width of a single heat exchange channel, in m; T f is the fluid temperature, in K; η is the rib efficiency; H ch is the height of a single heat exchange channel, in m; K a is the thermal conductivity of the material inside the heat exchange channel. For example, if the material inside the heat exchange channel is aluminum, then k a is the thermal conductivity of aluminum, i.e. k a =237; T R,up For the preset wall temperature factor, as described in the example above, there are 8 thermocouples placed on the base substrate to sense the temperature, of which 4 thermocouples can be set on the preset wall, and the preset wall temperature factor can be associated with the temperatures sensed by the 4 thermocouples set on the preset wall. For example, the sensed temperature values ​​of two thermocouples close to the outlet of the heat exchange channel can be selected and two wall temperatures can be calculated from the two sensed temperature values, and the average value of the two wall temperatures can be used as the preset wall temperature, etc., which is not limited here.

[0091] It should be noted that Formula 2-6, Formula 2-7 and Formula 2-8 are synchronously coupled calculations. Formula 2-10 is used to calculate the temperature of the heat exchange medium in the single-phase section of the heat exchange channel. The single-phase section represents the channel section where the nanofluid working as heat exchange will not undergo two-phase changes; Formula 2-11 is used to calculate the temperature of the heat exchange medium in the two-phase section of the heat exchange channel. The two-phase section represents the channel section where the nanofluid working as heat exchange will undergo two-phase changes. In other words, in this embodiment, it is taken into account that the heat exchange medium continuously absorbs heat and undergoes a boiling phase change during the flow process, and has reached a gas-liquid two-phase flow state at the outlet. There is a point with a dryness of 0 that divides the flow boiling of the medium in the channel into two parts, namely the single-phase section and the two-phase section, and the calculation methods are planned separately to evaluate the temperature of the heat exchange medium in the heat exchange channel.

[0092] Furthermore, the calculation formula of hydraulic diameter can be shown as formula 3-1:

[0093]

[0094] Among them, D h is the hydraulic diameter. The meanings of other symbols match those of the same symbols in the previous text and will not be repeated here.

[0095] For example, nine heat exchange channels with a length of L = 250 mm, a width of d = 2 mm, and a height of h = 2 mm are connected in parallel. The hydraulic diameter of the heat exchange channel is 2 mm, which is a micro channel.

[0096] See also Figure 6 as well as Figure 7 , Figure 6 This is a schematic diagram of the wall superheat diagram of an embodiment of the preset heat exchange analysis of the present application. Figure 7 It is a schematic diagram of a channel convection heat transfer coefficient chart of an embodiment of the preset heat exchange analysis of the present application.

[0097] Figure 6 The graph shown could be a boiling curve, Figure 7 The chart shown can be the trend of the average convective heat transfer coefficient, and the boiling curve can reflect the trend of the wall superheat changing with the heat flux density during the heating process. In addition, HTC (Heat Transfer Coefficients) can be used to characterize the heat exchange in the channel under various working conditions. The treated heat exchange medium enters the heat exchange channel with a certain degree of supercooling. During the process of flowing from bottom to top in the heat exchange channel, it continuously absorbs the constant heat load continuously supplied by the target wall of the heat exchange channel. When the heat reaches a certain value, the heat exchange medium undergoes a phase change in the heat exchange channel and boiling occurs. Figure 6 as well as Figure 7 The purpose of such charts is to reflect the change of heat transfer efficiency of the heat exchange medium from single phase to two phase by plotting the boiling curve and average convection heat transfer coefficient trend of the working fluid under different heat flux density conditions.

[0098] Figure 6 This is a comparison chart of the wall superheat of the parallel heat exchange channel under 6 working conditions. Working conditions 0 to 5 are respectively the working fluid is R141b without applying an electromagnetic field, the working fluid is nanofluid without applying an electromagnetic field, the working fluid is R141b under applying an electric field (200V), the working fluid is nanofluid under applying an electric field (200V), the working fluid is nanofluid under applying a magnetic field (350mT), and the working fluid is nanofluid under applying an electromagnetic field at the same time. Figure 6 It can be seen that the HTC value under lower heat flux density increases at a lower rate, and the data of conditions 1, 2, and 3 are not much different. The HTC value has a more obvious change in the heat flux range of 2.604kW / m2 to 4.5kW / m2. For nanofluids, the maximum HTC values ​​that can be achieved in condition 3 with the electric field applied alone and condition 4 with the magnetic field applied alone in this range are 1526.445W / (m2·K) and 1688.683W / (m2·K), respectively, while condition 5 with two fields applied at the same time can reach 1713.837W / (m2·K), which is the maximum value in the whole range of conditions.

[0099] Figure 7It is a comparison chart of the average convective heat transfer coefficient of the parallel heat exchange channel under 6 working conditions. Figure 7 It can be seen that compared with pure refrigerant, the heat transfer effect of adding nanoparticles is the smallest, with an average of only 9% under the full range of operating conditions. The use of external electric field for enhancement is second, with an average heat transfer effect improvement of 17%. However, under the synergistic effect of nanofluid and electric field, the heat transfer effect is improved to 24%, indicating that the heat transfer efficiency is further improved under the synergistic enhancement. After using nanofluid and applying magnetic excitation, the average enhancement effect is increased to 29%. When the electromagnetic coupling field is applied after the nanofluid is used, the heat transfer effect is improved the most, with an average improvement of 36% under all conditions.

[0100] It should be understood that although Figure 1 as well as Figure 5 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1 as well as Figure 5 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0101] See also Figure 8 , Figure 8 It is a structural schematic diagram of an embodiment of the heat dissipation system of the present application.

[0102] In one embodiment, the heat dissipation system may include a heat exchange system 31 and a heat dissipation housing 32 as described in any of the above embodiments. The heat exchange system 31 may be disposed inside the heat dissipation housing 32.

[0103] In one embodiment, a computer program product is provided, including a computer program. When the computer program is executed by a processor, the steps of the channel heat exchange method described above are implemented, which will not be described in detail here.

[0104] See also Fig. 9 , Fig. 9 It is a structural diagram of an embodiment of a computer device of the present application.

[0105] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as shown in FIG. Fig. 9As shown. The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a channel heat exchange method is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0106] Those skilled in the art will understand that Fig. 9 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0107] In one embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the following steps may be implemented:

[0108] S101: Controlling the application of a preset electric field to an electrode medium located in a heat exchange channel; wherein the heat exchange channel is used for flowing nanofluid;

[0109] S102: controlling to apply a preset magnetic field to a magnetic medium located outside the heat exchange channel; wherein the magnetic medium is disposed on two opposite sides of the outside of the heat exchange channel;

[0110] S103: Passing the nanofluid with supercooling into the heat exchange channel to absorb heat.

[0111] In one embodiment, the processor can also implement the following steps when executing the computer program: using a preset heat exchange analysis method to analyze the heat exchange parameters of the heat exchange channel under different scenario conditions; wherein, under different scenario conditions, the experimental electric field and / or experimental magnetic field applied to the heat exchange channel are different; and selecting a preset electric field and a preset magnetic field based on the heat exchange parameters under different scenario conditions.

[0112] In one embodiment, the heat exchange parameters include wall superheat; when analyzing the heat flux density of the heat exchange channel, the processor can also implement the following steps when executing the computer program: obtain the thermal efficiency, input thermal power and target wall area of ​​the heat exchange channel; wherein the target wall is the side wall through which the nanofluid can flow; use the thermal efficiency to weight the input thermal power, and use the ratio of the weighted result to the target wall area as the heat flux density; use the heat flux density to evaluate the target wall temperature of the heat exchange channel, and use the difference between the target wall temperature and the saturation temperature of the heat exchange medium as the wall superheat.

[0113] In one embodiment, when obtaining the thermal efficiency of the heat exchange channel, the processor can also implement the following steps when executing the computer program: obtaining the mass flow rate of the heat exchange medium; wherein the mass flow rate of the heat exchange medium is associated with the mass flow rate of the nanofluid in a single heat exchange channel; obtaining the difference in cross-sectional area between the single heat exchange channel and the electrode medium, and weighting the difference in cross-sectional area using the number of heat exchange channels to obtain a first factor; wherein the cross-sectional area is the orthographic projection area of ​​the cross section perpendicular to the flow direction of the nanofluid; and taking the ratio between the mass flow rate of the heat exchange medium and the first factor as the thermal efficiency of the heat exchange channel.

[0114] In one embodiment, the heat exchange parameters include a channel convection heat transfer coefficient; when analyzing the channel convection heat transfer coefficient of the heat exchange channel, the processor can also implement the following steps when executing the computer program: weighting the width factor using the heat flux density of the heat exchange channel to obtain a second factor; wherein the width factor is associated with the fin width and the width of a single heat exchange channel; obtaining a temperature difference factor and a rib parameter factor, and weighting the rib parameter factor using the temperature difference factor to obtain a third factor; and using the ratio of the second factor to the third factor as the channel convection heat transfer coefficient.

[0115] In one embodiment, the temperature difference factor is associated with the target wall temperature of the heat exchange channel and the temperature of the heat exchange medium in the heat exchange channel, and the rib parameter factor is associated with the fin width, the rib efficiency and the height of a single heat exchange channel; when obtaining the target wall temperature, the processor can also implement the following steps when executing the computer program: taking the ratio of a preset wall temperature factor to a temperature parameter as the target wall temperature; wherein the preset wall is opposite to the target wall, the preset wall temperature factor is associated with the temperature of the sensed preset wall, and the distance between the temperature sensing component and the target wall, the temperature parameter and the heat flux density and the thermal conductivity of the material inside the heat exchange channel; and / or, when obtaining the rib efficiency, the processor can also implement the following steps when executing the computer program: obtaining the rib parameters and the height of a single heat exchange channel, and evaluating the rib efficiency based on the rib parameters and the height of the single heat exchange channel.

[0116] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the following steps can be implemented:

[0117] S101: Controlling the application of a preset electric field to an electrode medium located in a heat exchange channel; wherein the heat exchange channel is used for flowing nanofluid;

[0118] S102: controlling to apply a preset magnetic field to a magnetic medium located outside the heat exchange channel; wherein the magnetic medium is disposed on two opposite sides of the outside of the heat exchange channel;

[0119] S103: Passing the nanofluid with supercooling into the heat exchange channel to absorb heat.

[0120] In one embodiment, when the computer program is executed by the processor, the following steps can also be implemented: using a preset heat exchange analysis method to analyze the heat exchange parameters of the heat exchange channel under different scenario conditions; wherein, under different scenario conditions, the experimental electric field and / or experimental magnetic field applied to the heat exchange channel are different; and selecting a preset electric field and a preset magnetic field based on the heat exchange parameters under different scenario conditions.

[0121] In one embodiment, the heat exchange parameters include wall superheat; when analyzing the heat flux density of the heat exchange channel, the computer program can also implement the following steps when executed by the processor: obtain the thermal efficiency, input thermal power and target wall area of ​​the heat exchange channel; wherein the target wall is the side wall through which the nanofluid can flow; use the thermal efficiency to weight the input thermal power, and use the ratio of the weighted result to the target wall area as the heat flux density; use the heat flux density to evaluate the target wall temperature of the heat exchange channel, and use the difference between the target wall temperature and the saturation temperature of the heat exchange medium as.

[0122] In one embodiment, when obtaining the thermal efficiency of the heat exchange channel, the computer program can also implement the following steps when executed by the processor: obtaining the mass flow rate of the heat exchange medium; wherein the mass flow rate of the heat exchange medium is associated with the mass flow rate of the nanofluid in a single heat exchange channel; obtaining the difference in cross-sectional area between the single heat exchange channel and the electrode medium, and weighting the difference in cross-sectional area using the number of heat exchange channels to obtain a first factor; wherein the cross-sectional area is the orthographic projection area of ​​the cross section perpendicular to the flow direction of the nanofluid; and taking the ratio between the mass flow rate of the heat exchange medium and the first factor as the thermal efficiency of the heat exchange channel.

[0123] In one embodiment, the heat exchange parameters include a channel convection heat transfer coefficient; when analyzing the channel convection heat transfer coefficient of the heat exchange channel, the computer program can also implement the following steps when executed by the processor: weighting the width factor using the heat flux density of the heat exchange channel to obtain a second factor; wherein the width factor is associated with the fin width and the width of a single heat exchange channel; obtaining a temperature difference factor and a rib parameter factor, and weighting the rib parameter factor using the temperature difference factor to obtain a third factor; and using the ratio of the second factor to the third factor as the channel convection heat transfer coefficient.

[0124] In one embodiment, the temperature difference factor is associated with the target wall temperature of the heat exchange channel and the temperature of the heat exchange medium in the heat exchange channel, and the rib parameter factor is associated with the fin width, the rib efficiency and the height of a single heat exchange channel; when obtaining the target wall temperature, the computer program can also implement the following steps when it is executed by the processor: taking the ratio of a preset wall temperature factor to a temperature parameter as the target wall temperature; wherein the preset wall is opposite to the target wall, the preset wall temperature factor is associated with the temperature of the sensed preset wall, and the distance between the temperature sensing component and the target wall, the temperature parameter and the heat flux density and the thermal conductivity of the material inside the heat exchange channel; and / or, when obtaining the rib efficiency, the computer program can also implement the following steps when it is executed by the processor: obtaining the rib parameters and the height of a single heat exchange channel, and evaluating the rib efficiency based on the rib parameters and the height of the single heat exchange channel.

[0125] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0126] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0127] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application.

Claims

1. A channel heat exchange method, characterized in that: The channel heat exchange method comprises: Controlling the application of a preset electric field to the electrode medium located in the heat exchange channel; wherein the heat exchange channel is used to flow the nanofluid; Controlling the application of a preset magnetic field to a magnetic medium located outside the heat exchange channel; wherein the magnetic medium is disposed on two opposite sides of the outside of the heat exchange channel; A nanofluid with a supercooling degree is introduced into the heat exchange channel to absorb heat.

2. The channel heat exchange method according to claim 1, characterized in that: The channel heat exchange method also includes: Using a preset heat exchange analysis method, the heat exchange parameters of the heat exchange channel under different scene conditions are analyzed; wherein under the different scene conditions, the experimental electric field and / or experimental magnetic field applied to the heat exchange channel is different; The preset electric field and the preset magnetic field are selected based on the heat exchange parameters under the different scene conditions.

3. The channel heat exchange method according to claim 2, characterized in that: The heat exchange parameters include wall superheat; Analyzing the wall superheat of the heat exchange channel includes: Obtaining the thermal efficiency, input heat power and target wall area of ​​the heat exchange channel; wherein the target wall is the side wall through which the nanofluid can flow; weighting the input thermal power using the thermal efficiency, and taking the ratio of the weighted result to the target wall area as the heat flux density; The heat flux density is used to evaluate the target wall temperature of the heat exchange channel, and the difference between the target wall temperature and the saturation temperature of the heat exchange medium is used as the wall superheat.

4. The channel heat exchange method according to claim 3, characterized in that: The obtaining of the thermal efficiency of the heat exchange channel comprises: Obtaining a mass flow rate of a heat exchange medium; wherein the mass flow rate of the heat exchange medium is associated with the mass flow rate of the nanofluid in a single heat exchange channel; Obtaining a difference in cross-sectional area between the single heat exchange channel and the electrode medium, and weighting the difference in cross-sectional area by the number of the heat exchange channels to obtain a first factor; wherein the cross-sectional area is an orthographic projection area of ​​a cross section perpendicular to a flow direction of the nanofluid; The ratio between the mass flow rate of the heat exchange medium and the first factor is used as the thermal efficiency of the heat exchange channel.

5. The channel heat exchange method according to claim 2, characterized in that: The heat exchange parameters include the channel convection heat transfer coefficient; analyzing the channel convection heat transfer coefficient of the heat exchange channel includes: The width factor is weighted by the heat flux density of the heat exchange channel to obtain a second factor; wherein the width factor is associated with the fin width and the width of a single heat exchange channel; Obtaining a temperature difference factor and a rib parameter factor, and weighting the rib parameter factor using the temperature difference factor to obtain a third factor; The ratio of the second factor to the third factor is used as the channel convection heat transfer coefficient.

6. The channel heat exchange method according to claim 5, characterized in that: The temperature difference factor is associated with the target wall temperature of the heat exchange channel and the temperature of the heat exchange medium in the heat exchange channel, and the fin parameter factor is associated with the fin width, fin efficiency and the height of a single heat exchange channel; Acquiring the target wall temperature includes: taking the ratio of a preset wall temperature factor to a temperature parameter as the target wall temperature; wherein the preset wall is opposite to the target wall, the preset wall temperature factor is associated with the temperature sensed by the preset wall, the distance between the temperature sensing component and the target wall, the temperature parameter is associated with the heat flux density and the thermal conductivity of the material inside the heat exchange channel; and / or, Acquiring the rib efficiency includes: acquiring rib parameters and a height of a single heat exchange channel, and evaluating the rib efficiency based on the rib parameters and the height of the single heat exchange channel.

7. A heat exchange system, characterized in that: The heat exchange system comprises: A heat exchange channel for circulating the nanofluid; A preheating component, disposed at the upstream side of the heat exchange channel, for heating the nanofluid; An electrode medium is disposed in the heat exchange channel; Magnetic media are arranged on two opposite sides of the outside of the heat exchange channel; A control module, used to implement the channel heat exchange method as described in any one of claims 1-6.

8. The heat exchange system according to claim 7, characterized in that: The heat exchange system further comprises: A liquid storage component, used for storing the nanofluid; A condensation component, disposed at the downstream side of the heat exchange channel, for condensing the nanofluid flowing out of the heat exchange channel; A driving component is used to drive the inner circulation of the nanofluid self-heat exchange system; a preset wall temperature factor parameter sensing component is used to sense the operating parameters required by the preset heat exchange analysis method.

9. A heat dissipation system, characterized in that: The heat dissipation system comprises: The heat exchange system according to any one of claims 7 or 8; A heat dissipation shell, wherein the heat exchange system is arranged inside the heat dissipation shell.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the channel heat exchange method according to any one of claims 1 to 6 are implemented.

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