Heat dissipation device and electronic device

Abstract

The application provides a heat dissipation device and an electronic device, and relates to the technical field of circuits.The heat dissipation device comprises a first cavity, a bottom plate of the first cavity being provided with an air hole; a second cavity, the second cavity being filled with cooling liquid, the second cavity comprising a flow channel; and a piezoelectric sheet, the piezoelectric sheet being located between the first cavity and the second cavity, the piezoelectric sheet vibrating based on an alternating electric field to drive air to be discharged from the first cavity or to be sucked into the first cavity, and to drive the cooling liquid to flow along the flow channel. Based on the scheme, the heat dissipation capacity of the heat dissipation device can be further increased.

Description

Technical Field

[0001] This application relates to the field of circuit technology, and more specifically, to heat dissipation devices and electronic devices. Background Technology

[0002] As the power of electronic components continues to increase, the performance of electronic devices has improved significantly. However, this has also made heat dissipation a more prominent issue. Poor heat dissipation can lead to overheating, affecting the stability and reliability of electronic devices and potentially even burning out circuit boards. To address this, heat dissipation devices utilizing piezoelectric resonant jet technology can be introduced. However, these devices are limited by their operating principles and overall structural design, resulting in relatively limited heat dissipation efficiency (or capacity). Therefore, further improving the heat dissipation capacity of these devices is a pressing issue that needs to be addressed. Summary of the Invention

[0003] This application provides a heat dissipation device and an electronic device, which helps to further improve the heat dissipation capacity of the heat dissipation device.

[0004] In a first aspect, a heat dissipation device is provided, comprising: a first chamber, the bottom plate of which is provided with vents; a second chamber filled with coolant, the second chamber including a flow channel; and a piezoelectric sheet located between the first chamber and the second chamber, the piezoelectric sheet vibrating based on an alternating electric field to drive gas out of or into the first chamber, and to drive coolant to flow along the flow channel.

[0005] In conjunction with the first aspect, in some implementations of the first aspect, the aforementioned flow channel includes a first flow channel and a second flow channel, the first flow channel and the second flow channel are disposed on both sides of the second chamber, the inlet and outlet of the first flow channel are located on the first side of the middle region of the second chamber, and the outlet of the first flow channel is located on the side of the inlet of the first flow channel away from the piezoelectric element, the inlet and outlet of the second flow channel are located on the second side of the middle region, and the outlet of the second flow channel is located on the side of the inlet of the second flow channel away from the piezoelectric element.

[0006] In conjunction with the first aspect, in some implementations of the first aspect, the diameter of the inlet of the first flow channel is smaller than the diameter of the main body section of the first flow channel, and / or the diameter of the outlet of the first flow channel is smaller than the diameter of the main body section of the first flow channel; the diameter of the inlet of the second flow channel is smaller than the diameter of the main body section of the second flow channel, and / or the diameter of the outlet of the second flow channel is smaller than the diameter of the main body section of the second flow channel.

[0007] In conjunction with the first aspect, in some implementations of the first aspect, the heat dissipation device further includes: a first power generation unit located in a second chamber, the first power generation unit including: a first electrode plate, a second electrode plate, and a porous structure layer, the porous structure layer being located between the first electrode plate and the second electrode plate, the porous structure layer including multiple through holes, through which coolant passes through the porous structure layer; wherein, the first electrode plate is connected to the cathode of the first battery, the second electrode plate is connected to the anode of the first battery, and the first battery is used to store the electrical energy generated by the porous structure layer.

[0008] In conjunction with the first aspect, in some implementations of the first aspect, the coolant includes first ions, and the sidewall of the through hole includes second ions, wherein the first ions and the second ions have opposite electrical properties.

[0009] In conjunction with the first aspect, in some implementations of the first aspect, the aforementioned porous structure layer is perpendicular to the flow direction of the coolant.

[0010] In conjunction with the first aspect, in some implementations of the first aspect, the aforementioned porous structure layer is disposed in the intermediate region.

[0011] In conjunction with the first aspect, in some implementations of the first aspect, the number of the aforementioned first power generation units is multiple, and the multiple first power generation units are distributed in at least one of the first flow channel, the second flow channel, and the intermediate region, and the multiple first power generation units are connected in series or in parallel.

[0012] In conjunction with the first aspect, in some implementations of the first aspect, the aforementioned through hole is a tapered hole.

[0013] In conjunction with the first aspect, in some implementations of the first aspect, the aforementioned multiple through holes are interconnected.

[0014] In conjunction with the first aspect, in some implementations of the first aspect, the first electrode plate includes a plurality of holes, and the second electrode plate includes a plurality of holes.

[0015] In conjunction with the first aspect, in some implementations of the first aspect, the heat dissipation device further includes: a second power generation unit disposed on the outer side of the top plate of the second chamber, the second power generation unit including: a third electrode plate, a fourth electrode plate and a thermoelectric thin film, the thermoelectric thin film being located between the third electrode plate and the fourth electrode plate; wherein, the third electrode plate is connected to the cathode of the second battery, the fourth electrode plate is connected to the anode of the second battery, and the second battery is used to store the electrical energy generated by the thermoelectric thin film.

[0016] In conjunction with the first aspect, in some implementations of the first aspect, the heat dissipation device further includes: a heat-conducting layer, the top surface of which contacts the heat dissipation target, and the bottom surface of which contacts the second power generation unit.

[0017] In conjunction with the first aspect, in some implementations of the first aspect, the top plate of the second chamber includes a groove that is exposed on the outside of the second chamber, and the second power generation unit is disposed within the groove.

[0018] In conjunction with the first aspect, in some implementations of the first aspect, the number of the aforementioned second power generation units is multiple, and these multiple second power generation units are connected in series or in parallel.

[0019] In conjunction with the first aspect, in some implementations of the first aspect, the sidewall of the first chamber includes an elastic material, the first end of the piezoelectric sheet is fixed to one sidewall of the first chamber by a first elastic member, and the second end of the piezoelectric sheet is fixed to the other sidewall of the first chamber by a second elastic member.

[0020] In conjunction with the first aspect, in some implementations of the first aspect, the heat dissipation device further includes an isolation membrane, and the piezoelectric sheet and the second chamber are separated by the isolation membrane.

[0021] In conjunction with the first aspect, in some implementations of the first aspect, the piezoelectric element is connected to an AC power source, and the heat dissipation device further includes a controller connected to the AC power source for controlling the frequency and amplitude of the AC power source.

[0022] In a second aspect, an electronic device is provided, including a heat dissipation target and a heat dissipation device in any possible implementation of the heat dissipation device design as described in the first aspect above. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a heat dissipation device utilizing synthetic jet technology.

[0024] Figure 2 This is a schematic diagram of the structure of a heat dissipation device 200 according to an embodiment of this application;

[0025] Figure 3 This is a schematic diagram of the structure of another heat dissipation device 200 proposed in the embodiments of this application;

[0026] Figure 4 This is a schematic diagram of the structure of another heat dissipation device 200 proposed in the embodiments of this application;

[0027] Figure 5 This is a schematic diagram of the structure of another heat dissipation device 200 proposed in the embodiments of this application;

[0028] Figure 6 This is a schematic diagram of the structure of another heat dissipation device 200 proposed in the embodiments of this application;

[0029] Figure 7This is a schematic diagram of the structure of another heat dissipation device 200 proposed in the embodiments of this application;

[0030] Figure 8 This is a schematic diagram of the structure of another heat dissipation device 200 proposed in the embodiments of this application;

[0031] Figure 9 This is a schematic diagram of another heat dissipation device 200 proposed in the embodiments of this application. Detailed Implementation

[0032] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0033] This application will present various aspects, embodiments, or features relating to a system comprising multiple devices, components, modules, etc. It should be understood and appreciated that individual systems may include additional devices, components, modules, etc., and / or may not include all the devices, components, modules, etc. discussed in conjunction with the accompanying drawings. Furthermore, combinations of these approaches are also possible.

[0034] Furthermore, in the embodiments of this application, the words "exemplary," "for example," etc., are used to indicate that they are examples, illustrations, or descriptions. Any embodiment or design scheme described as "exemplary" in the embodiments of this application should not be construed as being better or more advantageous than other embodiments or design schemes. Specifically, the use of the term "exemplary" is intended to present the concept in a concrete manner.

[0035] The business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0036] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0037] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0038] In the description of the embodiments of this application, the terms "upper," "lower," "left," "right," "inner," "outer," "vertical," and "horizontal," etc., indicate the orientation or positional relationship relative to the orientation or position of the components shown in the accompanying drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and not to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. They can change accordingly depending on the orientation of the components in the accompanying drawings, and therefore should not be construed as limiting this application.

[0039] In the embodiments of this application, the same reference numerals are used to denote the same component or part. For the same part in the embodiments of this application, only one part or component may be labeled with reference numerals in the figures. It should be understood that the reference numerals also apply to other identical parts or components. In addition, the various parts in the figures are not drawn to scale, and the dimensions and sizes of the parts shown in the figures are only exemplary and should not be construed as limiting this application.

[0040] As the power of electronic components continues to increase, the performance of electronic devices has improved significantly. However, this has also made heat dissipation a more prominent issue. During operation, excessively high temperatures can negatively impact the performance of electronic components, such as reducing the lifespan of capacitors and resistors, degrading the performance of transformers and insulation materials, and causing transistor failure. Furthermore, excessively high temperatures can lead to damage to electronic devices, thermal aging of materials, cracking of low-melting-point welds, solder joint detachment, and reduced mechanical strength, directly affecting product quality. Therefore, effective heat dissipation management is crucial for ensuring stable operation of electronic devices, extending their lifespan, and improving product quality.

[0041] Based on this, a heat exchange scheme based on natural convection has been proposed in this field. However, the heat exchange efficiency of this scheme is very low, and the amount of heat that can be removed from the inside of electronic devices through natural convection is very limited. To address this, a solution using heat dissipation devices to cool electronic devices has been proposed to solve the problem of excessively high operating temperatures. For example, fans are used as heat dissipation devices. However, conventional fans are large in size, noisy, and cannot be integrated into ultra-thin products. Therefore, a thin and quiet heat dissipation device is needed.

[0042] In response, a heat dissipation device utilizing piezoelectric resonant jet technology (also known as synthetic jet technology) has been proposed in this field.

[0043] Figure 1 This is a schematic diagram of a heat dissipation device that utilizes synthetic jet technology.

[0044] refer to Figure 1 As shown, the heat dissipation device includes an excitation cavity covered by a diaphragm, with an orifice inside. The basic principle of this technology is that the diaphragm vibrates as a whole (or undergoes simple harmonic motion or resonant motion) based on external excitation, causing the airflow direction in the excitation cavity to change periodically. Therefore, by periodically blowing and drawing fluid into the excitation cavity, a series of ordered airflow vortex rings or vortex pairs are induced and generated outside the orifice. During the formation stage of the vortex rings or vortex pairs and their subsequent downstream convection migration, the surrounding fluid is continuously entrained and mixed by the fluid's inductive effect, thus forming a high-speed jet. This jet not only has high momentum, effectively carrying away heat, but also introduces surrounding air through the entrainment effect, forming a secondary flow that further enhances the heat dissipation effect. Moreover, it can achieve precise control and manipulation of the flow field.

[0045] When the diaphragm vibrates, the air in the excitation cavity conforms to the ideal gas equation, as shown in the following equation (1):

[0046] pV = nRT (1)

[0047] Where p represents the gas pressure, V represents the gas volume, n represents the amount of substance of the gas (usually in moles), R is a constant called the ideal gas constant, the value of R depends on the type of gas and the unit used, and T represents the thermodynamic temperature of the gas (usually in Kelvin).

[0048] Furthermore, assuming the temperature remains constant, the air pressure and air volume within the excitation chamber satisfy the following formula (2):

[0049] p0V0=p1V1=p1(V0+ΔV) (2)

[0050] Where p0V0=p1V1 is the expression of Boyle's Law, p0 represents the initial pressure of the gas, that is, the pressure state of the gas before the change of gas state; V0 represents the initial volume of the gas, that is, the size of the space occupied by the gas before the change of gas state; p1 represents the pressure of the gas after the change of state (e.g., gas compression or expansion caused by diaphragm resonance motion); V1 represents the volume occupied by the gas when the pressure becomes p1; ΔV=V1-V0 is used for the increase or decrease of the gas volume from the initial state to the final state.

[0051] Combining formulas (1) and (2) above, it can be seen that the internal air pressure and airflow of the heat dissipation device are related to the deformation of the diaphragm. Therefore, the deformation generated by the overall resonant motion of the diaphragm enables the air inside the heat dissipation device to flow. This airflow passes over the heat dissipation target, carrying the heat emitted by the target and dissipating it from the electronic device. Furthermore, heat dissipation devices based on synthetic jet technology do not require rotating parts such as fans, thus possessing advantages such as compact structure, low noise, and low energy consumption.

[0052] The aforementioned synthetic jet technology has shown significant advantages in terms of miniaturization and absence of mechanical wear in heat dissipation devices. However, it still faces two key bottlenecks in practical applications: the physical limitations of heat dissipation capacity and the non-negligible overall power consumption of the system. These two issues are intertwined and jointly restrict the large-scale application of the technology.

[0053] From the perspective of physical limitations in heat dissipation, the thermal management efficiency of piezoelectric jet devices is constrained by their inherent working mechanism and structural characteristics. Jet velocity, as a core parameter determining the intensity of convective heat transfer, has a theoretical maximum value limited by the product of the maximum deformation amplitude of the piezoelectric material and its vibration frequency. Taking the currently mainstream lead zirconate titanate-5H (PZT-5H) piezoelectric ceramic as an example, its uniaxial strain under a saturated electric field is only 0.15%-0.2%. Even under 40kHz high-frequency driving conditions, the peak displacement of the vibrating diaphragm is difficult to exceed 20μm, which directly limits the airflow velocity at the nozzle outlet to the range of 15-25m / s. Compared to the airflow velocity of traditional centrifugal fans, which often exceeds 40m / s, this difference in velocity magnitude results in an inherent deficiency in the heat exchange efficiency of piezoelectric jets in forced convection cooling scenarios. This is especially true when processing power densities exceeding 50W / cm². 2 When using high heat flux density devices, the boundary layer thickening effect caused by insufficient jet flux can lead to a significant increase in the local temperature gradient on the heat dissipation surface.

[0054] The insufficient turbulence intensity further exacerbates the limitation on heat dissipation capacity. Although the vortex ring structure formed by the piezoelectric jet after leaving the nozzle has good flow stability, its turbulence pulsation intensity is generally lower than that of the disordered turbulence generated by a traditional mechanical fan. Experimental measurements show that at a distance of 10 mm from the nozzle, the turbulence intensity coefficient of the piezoelectric jet is only 0.08-0.12, while the turbulence intensity of the airflow from a mechanical fan at the same distance can reach over 0.25. This difference directly affects the contact efficiency between the heat dissipation surface and the airflow, especially on the surface of heat dissipation fins with complex three-dimensional structures. The flow characteristics of low-turbulence airflow easily form local flow dead zones, resulting in a 30%-40% decrease in heat transfer efficiency in key heat dissipation areas such as the fin roots. More seriously, when multiple jet devices work together in an array, the interference effect between adjacent jets can cause premature breakage of the vortex ring structure, resulting in a significant velocity decay phenomenon in the overlapping part of the effective heat dissipation area. The overall heat dissipation capacity of the array exhibits a nonlinear decreasing trend, which is particularly pronounced in large-scale arrays with more than 16 elements.

[0055] The heat dissipation bottleneck caused by space constraints cannot be ignored. While the compact design of piezoelectric jet devices offers advantages in terms of size, the limited volume variation caused by the microcavity severely restricts the gas throughput of a single jet. Typical commercial devices typically have a cavity volume of 0.1-0.5 cm³. 3 Within this range, at a driving frequency of 100Hz, the gas exchange volume per cycle is only 0.02-0.1mL, resulting in a driving airflow rate per unit time that is 1-2 orders of magnitude lower than that of traditional fans. When applied to scenarios requiring large-scale heat dissipation, such as server racks or power electronics cabinets, the limited airflow penetration depth drastically worsens the temperature control effect in the far-end heat dissipation areas. Actual measurement data from a piezoelectric jet cooling module used in a data center shows that at a depth of 1.5m... 3 Within the enclosed space, the airflow velocity at a distance of 30cm from the device has decreased to 18% of its initial value, causing the temperature of the heat dissipation surface in that area to rise by 22°C compared to the near-end area.

[0056] Insufficient temperature gradient adaptability is another key limiting factor. The operating characteristics of piezoelectric jet devices mean that, under fixed driving parameters, they can only maintain optimal heat dissipation performance within a specific temperature range. When the temperature distribution of the object being cooled changes dynamically, this lack of adaptive adjustment capability becomes significantly apparent. For example, in the intermittent high-load conditions of electronic equipment, the surface temperature of the heat dissipation device may jump by 40-60°C within seconds. If the jet device maintains constant driving conditions, the increase in its heat transfer capacity will lag significantly behind the rate of temperature change. This lack of dynamic response stems from the electromechanical coupling characteristics of the piezoelectric material itself—the strain output of the piezoelectric ceramic is highly dependent on the driving voltage, and rapid adjustment of the driving voltage can cause problems such as resonant frequency shift, ultimately leading to a 20%-30% fluctuation in heat dissipation performance under transient thermal shock scenarios.

[0057] The persistently high overall power consumption of the system constitutes another insurmountable technical obstacle. The intrinsic properties of piezoelectric materials dictate that significant energy loss is inevitable during energy conversion. Taking widely used hard piezoelectric ceramics as an example, at a working frequency of 20kHz, the dielectric loss tangent (tanδ) of the material typically reaches 1.5%-2.5%, meaning that more than a quarter of the input electrical energy is directly lost as heat. Even more seriously, the inherent hysteresis of the piezoelectric effect leads to a phase difference between mechanical deformation and electric field changes. This nonlinear loss can reduce the effective energy conversion efficiency by 15%-20% under dynamic operating conditions. Energy audit data from a certain type of piezoelectric jet device shows that, under rated operating conditions, only 38% of the electrical energy is ultimately converted into effective jet kinetic energy, with the remaining energy wasted in the form of heat loss, mechanical internal friction, etc.

[0058] The energy loss in the drive circuit further amplifies the system's power consumption problem. To achieve the high-frequency, high-voltage drive required for piezoelectric materials, the efficiency loss of the power amplifier circuit becomes a significant factor. A typical Class D amplifier, when converting a low-voltage signal to a 200Vpp high-voltage waveform, typically has an energy conversion efficiency between 75% and 85%, meaning that the drive stage alone causes a 15%-25% energy loss. When the device's operating frequency enters the ultrasonic range (>20kHz), the dynamic losses of the switching devices increase exponentially with frequency. Under 100kHz drive conditions, MOSFET switching losses can account for more than 30% of the total system power consumption. This high-frequency loss characteristic severely restricts the applicability of the device under high-frequency conditions, forcing designers to make a difficult trade-off between heat dissipation efficiency and power consumption levels.

[0059] The contradictory relationship between heat dissipation requirements and increasing power consumption creates a vicious cycle. As the heat load on the object being cooled increases, it is often necessary to increase the driving voltage or operating frequency to maintain the necessary heat dissipation capacity, but this directly leads to a quadratic increase in system power consumption. Experimental data shows that when the driving voltage is increased from 150Vpp to 250Vpp, the linear increase in jet velocity is 40%, while the power consumption increases by 127%. This nonlinear relationship is even more pronounced in high-temperature environments because the dielectric loss of piezoelectric materials increases by an additional 0.3% / ℃ at high temperatures. This causes the system to actually fall into a negative feedback loop when dealing with high heat loads: "increased heat dissipation requirements lead to a surge in power consumption, which in turn leads to a greater increase in device temperature, and ultimately to material performance degradation."

[0060] The dual limitations of heat dissipation capacity and power consumption jointly shape the application boundaries of piezoelectric jet technology. In the field of mobile electronic devices, although its thinness advantage is highly attractive, the sensitivity of battery life and the strong positive correlation with power consumption have led to a lower-than-expected actual adoption rate. Engineering tests of a certain tablet computer showed that although the piezoelectric jet solution reduced the body thickness by 1.2mm, the overall battery life was reduced by 23%, a cost that is clearly unacceptable in the consumer electronics market. In scenarios such as data centers with stringent requirements for heat dissipation performance, the limited heat dissipation capacity per unit area forces the system to be equipped with more components, and the resulting cumulative power consumption effect makes the overall power consumption exceed that of traditional heat dissipation solutions, which runs counter to the industry's goal of optimizing high power usage effectiveness (PUE).

[0061] The fundamental limitations of material physics properties make it difficult to completely solve the above problems through local optimization. The theoretical upper limit of the electromechanical coupling coefficient of piezoelectric materials is about 0.35-0.4, which fundamentally defines the efficiency ceiling for the conversion of electrical energy to mechanical energy. Even with an idealized lossless driving circuit, the theoretical maximum efficiency of piezoelectric jet devices is difficult to exceed 50%, and in actual engineering implementation, energy losses from fluid-structure interaction, turbulence dissipation, and other factors must be deducted. This efficiency limitation at the level of physical laws means that piezoelectric jet technology always faces an inherent disadvantage in energy efficiency when competing with electromagnetically driven heat dissipation solutions.

[0062] A significant application gap exists between market demand and current technological capabilities. The industrial sector has an increasingly urgent need for heat dissipation in chips exceeding 200W, but existing piezoelectric jet devices hover around a heat dissipation capacity of 30-50W per module, forcing systems to adopt complex multi-stage heat dissipation architectures. Each additional heat dissipation stage introduces new interfacial thermal resistance and energy loss, ultimately leading to a decrease in system-level heat dissipation capacity. This limitation is particularly pronounced in emerging fields such as power module heat dissipation in electric vehicles. The stringent size and weight constraints of the automotive environment mean that piezoelectric jet devices cannot provide sufficient heat dissipation within limited space, nor can they meet the low-power requirements of vehicle energy management.

[0063] Therefore, the heat dissipation device and electronic device proposed in this application embodiment help to further improve the heat dissipation capacity of the heat dissipation device, thereby achieving a better heat dissipation effect.

[0064] Figure 2 This is a schematic diagram of the structure of a heat dissipation device 200 according to an embodiment of this application. Figure 2 This is a longitudinal cross-sectional view of the heat dissipation device 200.

[0065] refer to Figure 2 As shown, the heat dissipation device 200 includes:

[0066] The first chamber 210 has a bottom plate 211 with vents 212.

[0067] A second chamber 220 is filled with coolant and includes a flow channel 221.

[0068] A piezoelectric element 230 is located between the first chamber 210 and the second chamber 220. The piezoelectric element 230 vibrates based on an alternating electric field to drive gas out of or into the first chamber 210, and to drive coolant to flow along the flow channel 221.

[0069] Based on the above structural description, it can be seen that the piezoelectric sheet 230 can serve as a divider for separating the first chamber 210 and the second chamber 220. Therefore, the first chamber 210 and the second chamber 220 can also be understood as belonging to a single main chamber. Figure 2In the structure shown, the upper part of the main chamber includes a flow channel 221, which serves as the second chamber 220 (i.e., the liquid chamber). The lower part of the main chamber includes a perforated plate, which serves as the bottom plate 211. The perforated plate has vent holes 212, which serve as the first chamber 210 (i.e., the gas chamber). The piezoelectric element 230 is used to divide the main gas chamber into the gas chamber and the liquid chamber. Therefore, with one side of the piezoelectric element 230 facing the gas and the other side facing the liquid, when the piezoelectric element 230 vibrates based on an alternating electric field, the vibration force can be used as a driving force. This driving force can either drive gas out of or into the first chamber 210, or drive the coolant in the second chamber 220 to flow along the flow channel 221.

[0070] In some possible embodiments, the piezoelectric sheet 230 can be a suspended piezoelectric sheet, fixed to the top of the first chamber 210, which is equivalent to being fixed to the bottom of the second chamber 220. For ease of description, the following description focuses on the fixing form of the piezoelectric sheet 230 to the first chamber 210.

[0071] In some possible embodiments, the first end of the piezoelectric sheet 230 can be fixed to a side wall of the first chamber 210 by a rigid component, thereby fixing the piezoelectric sheet 230 in a single cantilever structure fixing manner.

[0072] In some possible embodiments, Figure 2 The diagram shows a piezoelectric sheet 230 with a double cantilever structure. The first end of the piezoelectric sheet 230 is fixed to one side wall (also called a heat dissipation substrate) of the first chamber 210 via a first elastic member 270, and the second end of the piezoelectric sheet 230 is fixed to the other side wall of the first chamber 210 via a second elastic member 275. This fixing method increases the stability of the piezoelectric sheet 230 and better transmits the mechanical energy conducted when the piezoelectric sheet 230 vibrates. This allows the side wall of the first chamber 210 and the base plate 211 to vibrate based on this mechanical energy, thereby promoting the expulsion or intake of gas.

[0073] In some possible embodiments, the sidewall of the first chamber 210 may also include an elastic material, such that the sidewall as a whole is driven to deform by the mechanical energy conducted by the vibration of the piezoelectric sheet 230, thereby further promoting the exhaust or intake of gas.

[0074] In some possible embodiments, the piezoelectric sheet 230 and the first chamber 210 can also be fixed using thermally conductive adhesive or metal connectors with good thermal conductivity. The thermally conductive adhesive should have both elasticity and thermal conductivity to prevent fatigue cracks from forming on the surface of the thermally conductive adhesive after the piezoelectric sheet 230 has been working for a long time.

[0075] In some possible embodiments, the first chamber 210 described above may also be a support structure, and the piezoelectric sheet 230 may be fixed to the support structure.

[0076] In some possible embodiments, since the overall structure of the heat dissipation device 200 is small, the flow channel 221 in the second chamber 220 can also be called a microchannel. The microchannel can be manufactured by micron-level laser cutting or 3D printing technology to ensure that the coolant can flow smoothly during the vibration of the piezoelectric sheet 230, and the flow direction of the coolant is in line with the vibration direction of the piezoelectric sheet 230, thereby improving the heat dissipation efficiency of the fluid.

[0077] In some possible embodiments, the second chamber 220 is generally symmetrical, and the first flow channel 2211 and the second flow channel 2212 are symmetrical to each other and are symmetrically arranged in the second chamber 220.

[0078] In some possible embodiments, reference Figure 2 As shown, in the heat dissipation device 200, the flow channel 221 includes a first flow channel 2211 and a second flow channel 2212. The first flow channel 2211 and the second flow channel 2212 are disposed in the two side regions 01 of the second chamber 220. The inlet and outlet of the first flow channel 2211 are located on the first side A1 of the middle region 02 of the second chamber 220, and the outlet of the first flow channel 2211 is located on the side away from the piezoelectric element 230 from the inlet of the first flow channel 2211. The inlet and outlet of the second flow channel 2212 are located on the second side A2 of the middle region 02, and the outlet of the second flow channel 2212 is located on the side away from the piezoelectric element 230 from the inlet of the second flow channel 2212. Based on this, the vibration direction of the piezoelectric element 230 is generally vertically upward, thereby squeezing the coolant in the intermediate region 02 upward. This causes the coolant to flow from the inlet of the first flow channel 2211 on the first side A1 of the intermediate region 02 into the first flow channel 2211, and from the inlet of the second flow channel 2212 on the second side A2 of the intermediate region 02 into the second flow channel 2212. Correspondingly, during vibration, the piezoelectric element 230 also squeezes the coolant flowing out of the outlet of the first flow channel 2211 on the first side A1 of the intermediate region 02 upward, causing the flowing coolant to be squeezed to the top of the intermediate region 02, and then enter the inlets of the first flow channel 2211 and the second flow channel 2212 on both sides of the intermediate region 02, thus forming two coolant circulation loops. This ensures that the coolant flow direction is aligned with the vibration direction of the piezoelectric element 230.

[0079] In some possible embodiments, the heat dissipation device 200 further includes an isolation membrane 280, which separates the piezoelectric sheet 230 from the second chamber 220, thereby preventing the coolant in the second chamber 220 from leaking into the first chamber 210.

[0080] For example, the aforementioned isolation membrane 280 can be prepared based on sealant or sealing ring. Meanwhile, the sealing material should possess good thermal conductivity and corrosion resistance to ensure the long-term stable operation of the heat dissipation device 200.

[0081] In some possible embodiments, the piezoelectric element 230 can be connected to an AC power supply B3 (e.g., an AC signal generator), using an alternating electric field to cause the piezoelectric element 230 to vibrate at high frequency. The vibration frequency of the AC power supply B3 can be adjusted between a few hertz and tens of hertz, depending on the product's requirements for the heat dissipation efficiency of the heat sink 200. Therefore, the heat dissipation efficiency of the heat sink 200 can be dynamically adjusted.

[0082] In some possible embodiments, the size of the piezoelectric element 230 can be selected based on actual heat dissipation requirements and the size limitations of the liquid cooling system. An excessively large piezoelectric element may result in excessive power consumption, while an excessively small piezoelectric element may fail to meet heat dissipation requirements. Taking a circular piezoelectric element 230 as an example, its diameter can be designed between 20 mm and 30 mm, and its thickness can range from several hundred micrometers to several millimeters. For different application scenarios and requirements, the geometric parameters of the piezoelectric element 230 can be adaptively adjusted. These geometric parameters can be determined through one or more methods, such as experience, theoretical derivation, experimentation, or simulation.

[0083] In some possible embodiments, the flow channel 221 structure in the second chamber 220 can be designed to cooperate with the vibration direction of the piezoelectric sheet 230 and the airflow cooling direction, so that the coolant can flow in the flow channel 221 based on the vibration of the piezoelectric sheet 230, ensuring that the coolant flow velocity is moderate, thereby effectively removing heat. For example, the diameter of the main section of the flow channel 221 can be designed to be in the range of 50μm to 200μm, and the depth of the main section of the flow channel 221 can be designed to be in the range of 100μm to 500μm.

[0084] In some possible embodiments, the external design of the heat dissipation device 200 should also ensure a compact structure to facilitate its integration into electronic devices. For highly integrated electronic devices, the maximum length and width of the heat dissipation device 200 can be limited to the range of 30mm to 150mm, with the specific values ​​depending on the required heat dissipation capacity and installation space. The maximum thickness of the heat dissipation device 200 can be limited to the range of 5mm to 20mm to avoid making the heat dissipation device 200 too thick and heavy. Similarly, the geometric parameters of the heat dissipation device 200 can be determined through one or more methods, such as experience, theoretical derivation, experimentation, or simulation.

[0085] In some possible embodiments, the coolant filling the second chamber 220 should have good thermal conductivity, i.e., a high specific heat capacity. For example, a water-based liquid (such as deionized water, pure water, or a coolant with appropriate amounts of antifreeze and corrosion inhibitors) can be used to improve heat exchange efficiency.

[0086] Based on the above technical solution, a heat dissipation device integrates two heat dissipation mechanisms into its heat dissipation chambers, and drives the two chambers to dissipate heat using a single piezoelectric element. The introduction of liquid cooling technology directly improves the overall heat dissipation capacity of the device, effectively solving the problem of insufficient heat dissipation capacity of a single piezoelectric synthetic jet device in high-heat-load applications. This heat dissipation device enables high-power devices to maintain a low temperature during operation, effectively avoiding performance degradation caused by overheating and thus improving the reliability of the heat dissipation. Furthermore, this heat dissipation device provides a driving force for both heat dissipation chambers through a single piezoelectric element, increasing the integration of the device. Compared to two independent heat dissipation chambers, fewer parts are used, reducing manufacturing costs and simplifying the fabrication process. This also makes the heat dissipation device suitable for miniaturized and highly integrated electronic devices.

[0087] In addition, the heat dissipation capacity of the aforementioned heat dissipation device 200 can be further improved through the following design.

[0088] In some possible embodiments, reference Figure 2 As shown, the diameter of the inlet of the first flow channel 2211 is smaller than the diameter of the main body of the first flow channel 2211, and / or the diameter of the outlet of the first flow channel 2211 is smaller than the diameter of the main body of the first flow channel 2211; the diameter of the inlet of the second flow channel 2212 is smaller than the diameter of the main body of the second flow channel 2212, and / or the diameter of the outlet of the second flow channel 2212 is smaller than the diameter of the main body of the second flow channel 2212.

[0089] Designing the inlet or outlet diameter to be smaller than that of the main flow channel increases the flow velocity of the coolant entering or leaving the channel. This increased velocity enhances fluid turbulence and improves heat exchange efficiency between the fluid and the chamber sidewalls. Although a smaller diameter increases local resistance, the increased velocity results in smoother overall fluid flow within the channel, helping to reduce the system's total pressure drop.

[0090] Based on the above technical solutions, the heat dissipation capacity of heat dissipation devices can be further improved.

[0091] Furthermore, the present application addresses the issue of high overall power consumption and low energy efficiency of heat dissipation devices through the following further design of heat dissipation devices.

[0092] Figure 3 This is a schematic diagram of another heat dissipation device 200 proposed in the embodiments of this application.

[0093] refer to Figure 3 As shown, compared to Figure 2 The heat dissipation device 200 shown Figure 3 The heat dissipation device 200 shown further includes the following components:

[0094] A first power generation unit 240 is located within a second chamber 220. The first power generation unit 240 includes:

[0095] A first electrode plate 241, a second electrode plate 242, and a porous structure layer 243 are provided. The porous structure layer 243 is located between the first electrode plate 241 and the second electrode plate 242. The porous structure layer 243 includes multiple through holes H1 through which coolant passes. The first electrode plate 241 is connected to the cathode of the first battery B1, and the second electrode plate 242 is connected to the anode of the first battery B1. The first battery B1 is used to store the electrical energy generated by the porous structure layer 243.

[0096] The principle by which the coolant generates electrical energy through the porous structure layer 243 is based on the electrokinetic effect. The electrokinetic effect refers to the phenomenon where, when a charged liquid flows, charged ions (such as positive and negative ions) in the fluid separate due to friction. This separation leads to uneven charge distribution at the fluid-solid (or fluid-to-fluid) interface, and charge accumulation at the fluid-solid interface, thereby generating an electric field in the fluid (i.e., a potential difference along the flow direction within the fluid). This electric field can also be called the stream potential.

[0097] Among them, the porous material selected for the porous structure layer 243 is a key factor in power generation based on the electrodynamic effect. The electrodynamic effect depends on charge separation caused by liquid flow. Therefore, selecting a suitable porous material can significantly improve the power generation performance of the first power generation unit 240.

[0098] For example, inorganic materials (alumina, titanium dioxide), carbon materials (activated carbon, carbon nanotubes, graphene), and composite systems can be selected as materials for the porous structure layer 243.

[0099] In some possible embodiments, the aforementioned via H1 can also be referred to as a micro / nano channel, see reference. Figure 3 As shown, the porous structure layer 243 includes multiple building units, and gaps exist between these building units. These gaps can then be used to form at least a portion of the aforementioned through-holes H1 (Wiener channels). Based on this, it can be understood that the multiple through-holes H1 can be interconnected.

[0100] In some possible embodiments, the aforementioned electrokinetic effect relies on charge separation caused by liquid flow, so the coolant may include first ions, and the sidewalls of the aforementioned through-hole H1 may include second ions, wherein the first and second ions have opposite charges. (Reference) Figure 3 As shown, the first ion is a cation, and the second ion is an anion. During the generation of the electrokinetic effect, for a through-hole H1, the coolant ion concentration inside the through-hole H1 increases from low to high along the coolant flow direction.

[0101] Therefore, under the influence of the electrodynamic effect, a flow potential difference is generated within the micro / nano channel, referencing... Figure 3 As shown, the flow potential difference is formed at the first interface E. Below this interface E, the first ions in the coolant migrate directionally due to the electric field, causing the entire coolant to flow in a specified direction, thus generating an electric current. Correspondingly, above the first interface E, the concentration of the first ions may be unevenly distributed due to fluid flow, the electric field, and other factors. Under the influence of the concentration gradient, the first ions spontaneously diffuse from high-concentration areas to low-concentration areas, generating an electric current. Both types of current can be recovered through the first electrode plate 241 and the second electrode plate 242 and stored in the first power source B1.

[0102] It should be noted that, as Figure 3 As shown, the first electrode plate 241 and the porous structure layer 243 are not in contact, and there is a certain gap between them, so as to prevent the first electrode plate 241 from blocking the coolant from passing through the porous structure layer 243; similarly, the second electrode plate 242 and the porous structure layer 243 are also not in contact, and there is a certain gap between them, so as to prevent the second electrode plate 242 from blocking the coolant flowing out of the porous structure layer 243 from entering the corresponding flow channel.

[0103] In some possible embodiments, the first electrode plate 241 and the second electrode plate 242 may include multiple holes H2, thereby ensuring that the coolant can pass through the first electrode plate 241 and the second electrode plate 242 relatively easily. Moreover, the holes in the electrode plates can increase the contact area between the electrodes and the electrolyte, thereby increasing the charge storage capacity of the two electrodes.

[0104] In some possible embodiments, the porous structure layer 243 described above is perpendicular to the flow direction of the coolant.

[0105] In some possible embodiments, reference Figure 3As shown, the porous structure layer 243 can be disposed in the middle region 02 and parallel to the piezoelectric sheet 230, so that the flow direction of the water driven by the piezoelectric sheet 230 is perpendicular to the porous structure layer 243, thereby maximizing the power generation of the first power generation unit 240.

[0106] In some possible embodiments, the electrical energy generated by the first power generation unit 240 can be used to supply power to other devices in the electronic device.

[0107] For example, other devices could be electronic components in a circuit, light-emitting diodes (LEDs), lasers, etc.

[0108] In some possible embodiments, the electrical energy generated by the first power generation unit 240 can also be directly supplied back to the AC power source that drives the piezoelectric sheet 230 to vibrate through a DC-AC converter, frequency modulation element, phase modulation element, and amplitude modulation element.

[0109] Based on the above technical solution, by introducing a porous structure layer into the heat dissipation device, the coolant generates a flow potential when flowing through the porous structure layer, thereby generating electrical energy. This electrical energy can be stored to achieve energy recovery and self-powered operation, or it can be applied to other electrical devices, thereby increasing the energy efficiency of the heat dissipation device and indirectly reducing its power consumption.

[0110] When the coolant flows in the through hole H1, it can generate electrical energy not only based on the electrodynamic effect, but also generate static electricity (i.e., electrostatic effect) based on the friction between the coolant and the side wall of the through hole H1. This part of the static electricity can also be recovered by the first electrode plate 241 and the second electrode plate 242.

[0111] In some possible embodiments, the aforementioned through-hole H1 can be a tapered orifice, wherein the diameter of the inlet of through-hole H1 is larger than the diameter of the outlet of through-hole H1, or the diameter of the inlet of through-hole H1 is smaller than the diameter of the outlet of through-hole H1. Based on the above structural design of through-hole H1, the flow rate of coolant in through-hole H1 can be further promoted, thereby increasing the friction between the coolant and the sidewall of through-hole H1, thus increasing the amount of static electricity generated, and further increasing the power generation of the first power generation unit 240.

[0112] Figure 4 This is a schematic diagram of another heat dissipation device 200 proposed in the embodiments of this application.

[0113] refer to Figure 4 As shown, compared to Figure 3 The heat dissipation device 200 shown is in Figure 4In the heat dissipation device 200 shown, there can be multiple first power generation units 240 disposed in the second chamber 220. These multiple first power generation units 240 are distributed in at least one of the first flow channel 2211, the second flow channel 2212 and the intermediate region 02. The multiple first power generation units 240 are connected in series or in parallel.

[0114] Based on the above technical solution, the amount of electrical energy recovered by the heat dissipation device can be further increased, thereby further increasing the energy efficiency of the heat dissipation device.

[0115] Furthermore, the size and morphology design of the porous structure layer 243 significantly influence the intensity of the electrokinetic effect and the energy recovery efficiency. Different nanoscale structures (such as nanorods, nanowires, and nanoparticles) exhibit varying charge separation capabilities during liquid flow. Nanorods and nanowires (typically 10 nm to 100 nm in diameter) possess large specific surface areas and high liquid flow properties, which help enhance the interaction between the liquid and material interface, thereby strengthening the output of the electrokinetic effect. Nanoparticles (typically 1 nm to 100 nm in diameter) have smaller dimensions and larger surface areas, effectively enhancing the material's charge trapping ability, making them suitable for applications requiring high surface area or volume ratio. Moreover, by controlling the pore size and porosity, the flow potential output of porous materials (e.g., typically in the range of 1 nm to 1000 nm) can be further optimized. Macroporous structures provide larger fluid channels, while microporous structures facilitate the concentrated separation of charges.

[0116] In some possible embodiments, porous structure layers 243 of different thicknesses can be selected according to actual application requirements. For porous structure layers 243 of different thicknesses, the first power generation unit 240 can be divided into thin-film power generation units and bulk power generation units. Thin-film power generation units have lower weight and smaller volume, making them suitable for space-constrained applications. Furthermore, the thin-film form facilitates integration with other systems (such as microfluidic systems) to achieve efficient energy recovery. The film thickness is typically a few micrometers to tens of micrometers, and the substrate can be a transparent conductive material, such as conductive glass or a metal substrate, to maximize the exposed area in the application. Bulk power generation units typically have a larger volume and higher current output, making them suitable for high-power applications. By adjusting the size and shape of the unit, higher energy recovery capabilities can be provided under conditions of large fluid flow. The size of the bulk power generation unit can be adjusted according to the size of the fluid channel, typically around a few centimeters.

[0117] The design of the microstructure of the porous layer 243 affects the efficiency of charge separation when the coolant flows within it. By increasing the contact area between the coolant and the sidewalls of the porous layer 243, the charge separation efficiency and the generation of flow potential can be effectively enhanced.

[0118] For example, the through holes H1 in the porous structure layer 243 described above can be designed as linear, curved, or mesh structures (see reference). Figure 3 (As shown).

[0119] In some possible embodiments, the pore sizes of the multiple through-holes H1 can be designed in multiple levels, such as the following three levels: micropores, mesopores, and macropores, where micropores help to enhance the viscosity of the coolant, and macropores help to increase the flow rate of the coolant. Based on this design, the pore size range of the through-holes H1 can be adjusted from a few nanometers to several hundred nanometers.

[0120] In some possible embodiments, the porous structure layer 243 based on different materials can be prepared by different preparation processes. For example, the porous structure layer 243 including inorganic materials (such as TiO2, Al2O3) and composite materials can be prepared by the sol-gel method; the porous structure layer 243 including carbon-based materials (such as graphene, carbon nanotubes) or metallic materials (such as copper, silver) can be prepared by chemical vapor deposition (CVD); and the porous structure layer 243 based on thin film materials can be prepared by sputtering to achieve high structural precision and good surface quality.

[0121] In summary, the design parameters of the first power generation unit can be adaptively adjusted according to the basic requirements of the application scenario to achieve efficient energy conversion and power collection.

[0122] In addition, this application embodiment also designs a heat dissipation device 200 with the following structure from another design perspective to increase the energy efficiency of the heat dissipation device 200.

[0123] Figure 5 This is a schematic diagram of another heat dissipation device 200 proposed in the embodiments of this application.

[0124] refer to Figure 5 As shown, compared to Figure 2 The heat dissipation device 200 shown Figure 5 The heat dissipation device 200 shown further includes the following components:

[0125] A second power generation unit 250 is disposed outside the top plate 223 of the second chamber 220, and the second power generation unit 250 includes:

[0126] The third electrode plate 251, the fourth electrode plate 252, and the thermoelectric film 253 are located between the third electrode plate 251 and the fourth electrode plate 252. The third electrode plate 251 is connected to the cathode of the second battery B2, and the fourth electrode plate 252 is connected to the anode of the second battery B2. The second battery B2 is used to store the electrical energy generated by the thermoelectric film 253.

[0127] The thermoelectric thin film 253 generates electricity based on the Seebeck effect. The Seebeck effect reveals the physical mechanism by which different materials generate a potential difference under temperature variations: when a temperature gradient exists at the junction of two conductors or semiconductors, charge carriers (electrons or holes) diffuse from the high-temperature end to the low-temperature end, creating a potential difference (also called the Seebeck potential) across the materials. Based on this principle, thermoelectric power generation technology constructs thermoelectric devices composed of two different materials, utilizing the temperature difference between the contact surfaces to drive the directional movement of charge carriers, directly converting thermal energy into electrical energy. Therefore, by integrating the thermoelectric thin film 253 between the second chamber 220 and the heat dissipation target, efficient utilization of waste heat can be achieved. The two electrodes fixed on both sides of the thermoelectric thin film 253 form a closed loop. When the liquid-cooled plate absorbs heat from the heat dissipation target, the Seebeck potential is generated across the thermoelectric thin film 253 due to the temperature difference, driving the flow of charge carriers to form an electric current.

[0128] In some possible embodiments, the electrical energy generated by the second power generation unit 250 can be used to power other devices in the electronic device. For example, other devices may be electronic components in a circuit, LEDs, lasers, etc.

[0129] In some possible embodiments, the electrical energy generated by the second power generation unit 250 can also be directly supplied back to the AC power source that drives the piezoelectric sheet 230 to vibrate through a DC-AC converter, frequency modulation element, phase modulation element, and amplitude modulation element.

[0130] Based on the above technical solution, by introducing a second power generation unit into the heat dissipation device, the thermoelectric thin film in the second power generation unit can convert part of the heat into usable electrical energy and store this part of the electrical energy to achieve energy recovery and self-powering, or apply this part of the electrical energy to other electrical equipment, thereby increasing the energy efficiency of the heat dissipation device and thus indirectly reducing the power consumption of the heat dissipation device.

[0131] In some possible embodiments, reference Figure 5 The heat dissipation device 200 shown above may further include: a heat-conducting layer 260, the top surface of which is in contact with the heat dissipation target 300, and the bottom surface of which is in contact with the second power generation unit 250.

[0132] The aforementioned thermally conductive layer 260 may include a thermally conductive coating and / or a thermal interface material, thereby enabling the heat dissipated by the heat dissipation target 300 to be transferred to the thermoelectric thin film 253 more efficiently.

[0133] Based on the above technical solution, the temperature difference between the thermoelectric thin film 253 and the second chamber 220 can be increased as much as possible, thereby increasing the thermoelectric conversion efficiency.

[0134] Figure 6 This is a schematic diagram of another heat dissipation device 200 proposed in the embodiments of this application.

[0135] refer to Figure 6 As shown, compared to Figure 5 The heat dissipation device 200 shown is in Figure 6 In the heat dissipation device 200 shown, the top plate 223 of the second chamber 220 includes a groove 214, which is exposed on the outside of the second chamber 220, and the second power generation unit 250 is disposed in the groove 214.

[0136] Based on the above technical solution, the contact area between the thermoelectric thin film 253 and the top plate 223 of the second chamber 220 can be increased, thereby helping to increase the thermoelectric conversion efficiency.

[0137] Figure 7 This is a schematic diagram of another heat dissipation device 200 proposed in the embodiments of this application.

[0138] refer to Figure 7 As shown, compared to Figure 5 or Figure 6 The heat dissipation device 200 shown is in Figure 7 In the heat dissipation device 200 shown, there are multiple second power generation units 250, which are connected in series or in parallel. Series connection helps to increase the electromotive force output and ensure sufficient voltage, while parallel connection helps to increase the current output and improve the power generation capacity.

[0139] Based on the above technical solution, the amount of electrical energy recovered by the heat dissipation device can be further increased, thereby further increasing the energy efficiency of the heat dissipation device.

[0140] In some possible embodiments, the material of the thermoelectric thin film 253 takes into account thermoelectric properties (e.g., thermal conductivity, electronic conductivity, Seebeck coefficient, etc.), compatibility with liquid cooling systems, and feasibility of the fabrication process. The thermoelectric material used in the thermoelectric thin film 253 can be a semiconductor material, such as bismuth telluride (Bi2Te3) or antimony telluride (Sb2Te3); or it can be a high-temperature thermoelectric material, such as skutterudites or silicon-germanium alloys.

[0141] Furthermore, by performing appropriate doping and modulation (such as selenium doping, antimony doping, etc.) on the thermoelectric thin film 253, the Seebeck coefficient and electrical conductivity of the thermoelectric thin film 253 can be effectively improved, while the thermal conductivity can be reduced, thereby enhancing the thermoelectric effect.

[0142] In some possible embodiments, considering that an excessively thick thermoelectric film 253 may result in a high thermal conductivity, thus weakening the thermoelectric effect, while an excessively thin thermoelectric film 253 may not be able to withstand large temperature differences and external loads, the thickness of the thermoelectric film 253 needs to be adaptively adjusted according to the application scenario. For example, the thickness of the thermoelectric film 253 can be adaptively adjusted within the range of 1μm-10μm to balance the thermoelectric performance and mechanical strength of the thermoelectric film 253. Furthermore, the length and width dimensions of the thermoelectric film 253 can also be designed in conjunction with the spatial dimensions of the second chamber 220 and the temperature difference requirements. For example, the thermoelectric film 253 can be designed as a small unit, with the size of each thermoelectric film 253 ranging from 5mm×5mm to 10mm×10mm.

[0143] In some possible embodiments, the third electrode plate 251 and the fourth electrode plate 252 described above are key components for energy harvesting in the second power generation unit 250, and conductive metals (such as aluminum, copper, gold, etc.) are typically used as electrode materials. Furthermore, the electrode dimensions must be designed to ensure good electrical contact is formed at both ends of the thermoelectric film 253, and to guarantee effective current harvesting and conduction.

[0144] In some possible embodiments, the thermoelectric thin film 253 can generate a thermoelectric effect within a temperature difference range of 10-50°C. According to the principle of the thermoelectric effect, the greater the temperature difference, the stronger the electromotive force generated by the thermoelectric thin film 253. Therefore, the design of the thermoelectric thin film 253 needs to make full use of the temperature difference between the liquid cooling end and the heat source.

[0145] In some possible embodiments, the choice of fabrication process for the thermoelectric thin film 253 also directly affects the quality, performance, and processability of the thermoelectric thin film 253. For example, the thermoelectric thin film 253 can be fabricated by sputtering, CVD, solution deposition, and magnetron sputtering.

[0146] Figure 8 This is a schematic diagram of another heat dissipation device 200 proposed in the embodiments of this application.

[0147] refer to Figure 8 As shown, the first power generation unit 240 and the second power generation unit 250 can be integrated simultaneously into one unit. Figure 2 In the heat dissipation device 200 shown, the energy utilization rate (i.e., energy efficiency) of the heat dissipation device 200 can be further increased by superimposing the energy harvesting operations of the two power generation units, thereby indirectly reducing the power consumption of the heat dissipation device.

[0148] In some possible embodiments, when the heat dissipation surface of the heat dissipation target 300 is large, multiple heat dissipation devices 200 mentioned in the above embodiments can be connected together to form a fin structure, which is then positioned opposite to the heat dissipation target 300. Based on this, overall heat dissipation for a large-area heat dissipation target can be achieved, ensuring the heat dissipation effect. Furthermore, when the heat dissipation device 200 includes a power generation unit, the energy efficiency of the multiple heat dissipation devices 200 can be maintained at a high level.

[0149] Figure 9 This is a schematic diagram of another heat dissipation device 200 proposed in the embodiments of this application.

[0150] Compared to Figure 8 The heat dissipation device 200 shown is... Figure 9 The heat dissipation device 200 shown also includes:

[0151] The controller 290 is connected to the AC power supply B3, which is connected to the piezoelectric element 230. The controller 290 is used to control the frequency and amplitude of the AC power supply B3.

[0152] In some possible embodiments, any of the heat dissipation devices 200 proposed in the foregoing embodiments of this application (see reference) Figures 2 to 8 All of these can be equipped with the aforementioned controller 290. By controlling the frequency and amplitude of the AC power supply B3 through the controller 290, the flow rate of the coolant in the flow channel 221, as well as the frequency and volume of gas discharge or intake in the first chamber 210, can be further controlled.

[0153] For example, the flow rate of the coolant can be controlled within the range of 0.1 m / s to 1 m / s, and the specific flow rate value can be dynamically adjusted in combination with the real-time temperature of the heat dissipation target 300.

[0154] In some possible embodiments, reference Figure 9 As shown, a temperature sensor 295 can also be installed on the top surface of the second chamber 220. This temperature sensor 295 is connected to the controller 290 to send real-time temperature values ​​to the controller 290. The controller 290 can dynamically adjust the frequency and amplitude of the AC power supply B3 based on this temperature value to control the flow rate of the coolant and the frequency and volume of gas discharge or intake from the first chamber 210, thereby achieving automatic control by the controller 290. There is a positive correlation between the temperature value, the frequency and amplitude of the AC power supply B3, and the flow rate of the coolant.

[0155] Based on the above technical solution, the heat dissipation intensity of the heat dissipation device can be dynamically adjusted by introducing a controller. When the temperature of the heat dissipation target is high, the heat dissipation intensity of the heat dissipation device can be adaptively increased, so that there is a positive correlation between the heat dissipation intensity of the heat dissipation device and the temperature of the heat dissipation target. This can effectively avoid the waste of energy or insufficient heat dissipation intensity of the heat dissipation device.

[0156] In some possible embodiments, reference Figure 9 As shown, a pump 298 can also be installed in the second chamber 220. The pump 298 can be directly used to control the flow rate of the coolant in the flow channel 221, thereby reducing the workload of the piezoelectric element 230 and the AC power supply B3. It can be seen that the pump 298 can also be connected to the temperature sensor 295 to realize the automatic regulation of the pump 298.

[0157] It should be noted that the above Figures 2 to 9 The design points of the heat dissipation device 200 shown can be combined with each other to form heat dissipation devices 200 with more structural forms.

[0158] Furthermore, embodiments of this application also propose an electronic device that includes the aforementioned heat dissipation target and any heat dissipation device as proposed in embodiments of this application.

[0159] In some possible embodiments, the above-mentioned electronic device can be any terminal device with heat dissipation requirements, such as a television set, a monitoring screen, a standalone monitor, a laptop, a tablet computer, a smartphone, etc.

[0160] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A heat dissipation device, characterized in that, include: The first chamber has air holes in its bottom plate; A second chamber, the second chamber being filled with coolant, the second chamber including flow channels; A piezoelectric element is located between the first chamber and the second chamber. The piezoelectric element vibrates based on an alternating electric field to drive gas out of or into the first chamber and to drive the coolant to flow along the flow channel.

2. The heat dissipation device according to claim 1, characterized in that, The flow channel includes a first flow channel and a second flow channel. The first flow channel and the second flow channel are disposed on both sides of the second chamber. The inlet and outlet of the first flow channel are located on the first side of the middle region of the second chamber, and the outlet of the first flow channel is located on the side of the inlet of the first flow channel away from the piezoelectric element. The inlet and outlet of the second flow channel are located on the second side of the middle region, and the outlet of the second flow channel is located on the side of the inlet of the second flow channel away from the piezoelectric element.

3. The heat dissipation device according to claim 2, characterized in that, The diameter of the inlet of the first flow channel is smaller than the diameter of the main body section of the first flow channel, and / or the diameter of the outlet of the first flow channel is smaller than the diameter of the main body section of the first flow channel. The diameter of the inlet of the second flow channel is smaller than the diameter of the main body section of the second flow channel, and / or the diameter of the outlet of the second flow channel is smaller than the diameter of the main body section of the second flow channel.

4. The heat dissipation device according to claim 2 or 3, characterized in that, The heat dissipation device also includes: A first power generation unit is located within a second chamber. The first power generation unit includes a first electrode plate, a second electrode plate, and a porous structure layer. The porous structure layer is located between the first electrode plate and the second electrode plate and includes multiple through holes through which the coolant passes. The first electrode plate is connected to the cathode of a first battery, and the second electrode plate is connected to the anode of the first battery. The first battery is used to store the electrical energy generated by the porous structure layer.

5. The heat dissipation device according to claim 4, characterized in that, The coolant includes a first ion, and the sidewall of the through hole includes a second ion, wherein the first ion and the second ion have opposite electrical properties.

6. The heat dissipation device according to claim 4 or 5, characterized in that, The porous structure layer is perpendicular to the flow direction of the coolant.

7. The heat dissipation device according to any one of claims 4 to 6, characterized in that, The porous structure layer is disposed in the intermediate region.

8. The heat dissipation device according to any one of claims 4 to 6, characterized in that, The number of the first power generation units is multiple, and the multiple first power generation units are distributed in at least one of the first flow channel, the second flow channel and the intermediate region. The multiple first power generation units are connected in series or in parallel.

9. The heat dissipation device according to any one of claims 4 to 8, characterized in that, The through hole is a tapered hole.

10. The heat dissipation device according to any one of claims 4 to 9, characterized in that, The plurality of through holes are interconnected.

11. The heat dissipation device according to any one of claims 4 to 10, characterized in that, The first electrode plate includes multiple holes, and the second electrode plate includes multiple holes.

12. The heat dissipation device according to any one of claims 1 to 11, characterized in that, The heat dissipation device also includes: The second power generation unit is disposed on the outside of the top plate of the second chamber. The second power generation unit includes a third electrode plate, a fourth electrode plate, and a thermoelectric thin film. The thermoelectric thin film is located between the third electrode plate and the fourth electrode plate. The third electrode plate is connected to the cathode of the second battery, and the fourth electrode plate is connected to the anode of the second battery. The second battery is used to store the electrical energy generated by the thermoelectric thin film.

13. The heat dissipation device according to claim 12, characterized in that, The heat dissipation device further includes a heat-conducting layer, the top surface of which contacts the heat dissipation target, and the bottom surface of which contacts the second power generation unit.

14. The heat dissipation device according to claim 12 or 13, characterized in that, The top plate of the second chamber includes a groove that is exposed on the outside of the second chamber, and the second power generation unit is disposed within the groove.

15. The heat dissipation device according to any one of claims 12 to 14, characterized in that, There are multiple second power generation units, which are connected in series or in parallel.

16. The heat dissipation device according to any one of claims 1 to 15, characterized in that, The sidewall of the first chamber is made of an elastic material, the first end of the piezoelectric sheet is fixed to one sidewall of the first chamber by a first elastic element, and the second end of the piezoelectric sheet is fixed to the other sidewall of the first chamber by a second elastic element.

17. The heat dissipation device according to any one of claims 1 to 16, characterized in that, The heat dissipation device also includes an isolation membrane, and the piezoelectric sheet and the second chamber are separated by the isolation membrane.

18. The heat dissipation device according to any one of claims 1 to 17, characterized in that, The piezoelectric element is connected to an AC power supply, and the heat dissipation device further includes: A controller is connected to the AC power supply and is used to control the frequency and amplitude of the AC power supply.

19. An electronic device, characterized in that, It includes a heat dissipation target and a heat dissipation device as described in any one of claims 1 to 18.

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