High-speed auxiliary nozzle and special-shaped micro-fin jet microchannel for chip heat dissipation

Abstract

The present invention provides a high-speed auxiliary nozzle-coordinated, irregularly shaped micro-rib jet microchannel, comprising: a base plate, an intermediate plate, and a top cover plate; the base plate is provided with a plurality of free irregularly shaped micro-ribs distributed in an array, with gaps between the tops of the free irregularly shaped micro-ribs and the intermediate plate; the base plate is enclosed by a surrounding plate; the intermediate plate includes a plurality of microchannel inlet slots and a plurality of microchannel outlet slots, the bottom of the microchannel inlet slots being provided with a plurality of nozzles and a plurality of high-speed auxiliary nozzles, the inlet diameter of the high-speed auxiliary nozzles being the same as the nozzle diameter, and the outlet diameter being smaller than the nozzle diameter; the nozzles and the high-speed auxiliary nozzles being spaced apart. The present invention utilizes irregularly shaped micro-ribs to promote bubble nucleation, maintain the liquid film, and disrupt large bubbles / vapor films through jet impact. This effectively addresses the difficulties of conventional large-scale, smooth-surface jet boiling, such as difficulty in nucleation and poor heat transfer due to bubble merging and covering the heated surface, and significantly improves boiling heat transfer performance.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic chip heat dissipation, and in particular to a high-speed auxiliary nozzle coordinated with a special-shaped micro-fin jet microchannel for chip heat dissipation. Background Art

[0002] Miniaturization and integration are the driving forces of modern electronic devices. This has resulted in an increasing number of components per unit area, leading to a sharp increase in operating power consumption and heat generation. Thermal management technology plays a crucial role in ensuring the safe, reliable, and stable operation of high-power electronic devices such as lasers, radars, and microelectronics.

[0003] Microchannel jet impingement boiling heat transfer has broad application prospects in the field of high-heat-flux electronic chip cooling due to its advantages of high heat transfer coefficient, low pressure drop and thermal resistance, and compact system. A typical microchannel jet boiling heat transfer process involves a fluid vertically impacting a smooth wall from a nozzle, absorbing heat and then exiting in a cross-flow. The smooth surface of such a channel makes it difficult for bubbles to nucleate, and even more difficult to nucleate under jet impingement. Sometimes, nucleation remains unaffected even at wall temperatures far exceeding safe limits. Once bubbles nucleate, explosive boiling is likely to occur, accompanied by a sudden drop in wall temperature, triggering unstable flow. Furthermore, the liquid film on the smooth wall is difficult to maintain, making critical dry-out and wall temperature surges more likely. In particular, when a boiling phase transition occurs within a large heat source channel, a large number of bubbles coalesce to form a vapor film covering the heat source surface, which can prematurely trigger critical heat flux. This poses a significant safety risk to heat exchange equipment and power systems.

[0004] Therefore, promoting boiling bubble nucleation, maintaining the wall liquid film, breaking up large bubbles / vapor films, and increasing the critical heat flux are key issues that need to be addressed in the development of high-heat-flux jet microchannel heat exchange. However, currently, no jet microchannel technology can simultaneously address these technical issues. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention proposes a high-speed auxiliary nozzle for chip heat dissipation that cooperates with a special-shaped micro-rib jet microchannel. The special-shaped micro-ribs are used to promote bubble nucleation, maintain the liquid film, and jet impact to break up large bubbles / vapor films. This can effectively solve the problems of traditional smooth surface jet boiling that are difficult to nucleate and bubbles merge to cover the heating surface, worsening heat transfer, and significantly improve the boiling heat transfer performance.

[0006] The technical solution adopted in the present invention is as follows:

[0007] A high-speed auxiliary nozzle coordinated special-shaped micro-fin jet microchannel is provided, comprising: a bottom plate, an intermediate plate and a top cover plate;

[0008] The bottom plate is provided with a plurality of free-shaped micro-ribs distributed in an array, with a gap between the top of the free-shaped micro-ribs and the middle plate; the bottom plate is enclosed by a surrounding plate;

[0009] The middle plate includes a plurality of microchannel inlet slots and a plurality of microchannel outlet slots. The bottom of the microchannel inlet slots is provided with a plurality of nozzles and a plurality of high-speed auxiliary nozzles. The inlet diameter of the high-speed auxiliary nozzle is the same as the nozzle diameter, and the outlet diameter is smaller than the nozzle diameter. The nozzles and the high-speed auxiliary nozzles are arranged at intervals.

[0010] The top cover is arranged above the middle plate.

[0011] Furthermore, the ratio x of the gap to the bottom wall depth satisfies:

[0012] x=g / H≤0.3

[0013] In the above formula, g represents the gap between the top of the free-shaped micro-rib and the middle plate, and H represents the depth of the inner wall of the bottom plate.

[0014] Furthermore, the free special shapes include: single-slit cylindrical special-shaped micro-ribs, double-slit cylindrical special-shaped micro-ribs, cylindrical double-slit cylindrical special-shaped micro-ribs, single-slit square column special-shaped micro-ribs, double-slit square column special-shaped micro-ribs and / or cylindrical double-slit square column special-shaped micro-ribs.

[0015] Furthermore, the slit gap and cylinder diameter of the cylindrical double-slit special-shaped micro-ribs meet the following requirements:

[0016] m=s / D≤0.2,n=d / D≤0.3

[0017] In the above formula, m represents the ratio of the slit gap to the cylinder's major circle diameter, n represents the ratio of the cylinder's minor circle diameter to the cylinder's major circle diameter, s represents the slit gap, D represents the cylinder's major circle diameter, and d represents the cylinder's minor circle diameter.

[0018] Furthermore, the ratio y between the nozzle length and the middle plate thickness satisfies:

[0019] y=l0 / L≤0.6

[0020] In the above formula, l0 represents the length of the nozzle and L represents the thickness of the middle plate.

[0021] Furthermore, the high-speed auxiliary nozzle includes a front half and a rear half structure; the structure of the front half is consistent with the structure of the same part of the nozzle; the rear half is a concave-contracted structure, and its diameter is smaller than the diameter of the same part of the nozzle.

[0022] Furthermore, the length and aspect ratio of the rear half of the high-speed auxiliary nozzle are determined based on the high-speed auxiliary nozzle and the fluid pressure drop requirements within the nozzle. The fluid pressure drop requirements include:

[0023]

[0024] In the above formula, Indicates the pressure drop of the fluid in the high-speed auxiliary nozzle, Indicates the pressure drop of the fluid in the nozzle; the diameter of the front half of the high-speed auxiliary nozzle is d1, the length is l1, and the friction coefficient is f1; the diameter of the rear half is d2, the length is l2, and the friction coefficient is f2; the diameter of the nozzle is d0, and the length is l0;

[0025] The aspect ratio of the rear half of the high-speed auxiliary nozzle is r=l2 / d2.

[0026] Furthermore, the second half includes multiple sections of concave and convex structures, and the diameter of each section of the concave and convex structure becomes smaller from top to bottom.

[0027] Furthermore, the material of the base plate includes semiconductor material, metal or high thermal conductivity material;

[0028] The materials of the middle plate and the top cover plate include semiconductor materials, metals, high thermal conductivity materials or high temperature resistant polymer materials.

[0029] Furthermore, multiple inlet grooves of the microchannel and multiple outlet grooves of the microchannel are arranged in parallel on an intermediate plate. The inlet fluid is first evenly distributed through multiple parallel microchannel grooves, and then sprayed toward the microchannel bottom plate through the nozzle and the height auxiliary nozzle, and then passes through the interval distance of a horizontal inlet and outlet channel, and then flows vertically to the multiple parallel microchannel outlets and flows out.

[0030] It can be seen from the above technical solution that the beneficial technical effects of the present invention are as follows:

[0031] 1. The nozzle-high-speed auxiliary nozzle array structure, spaced apart, replaces the low inlet flow velocity of conventional manifold microchannels, significantly increasing the inlet flow rate. High flow rates improve convective heat transfer performance, while the high flow rates of the auxiliary nozzles prevent boiling phase transition bubbles from merging into large bubbles / films, which can degrade heat transfer performance.

[0032] 2. The free-form micro-rib structure has abundant surface energy mutation points, which can promote the nucleation of fluid bubbles; the slits inside the special-shaped micro-ribs help maintain the liquid film, which is beneficial to improving the boiling heat transfer performance.

[0033] 3. Collaborative nozzles - high-speed auxiliary nozzle arrays and free-shaped micro-fin arrays, by collaboratively utilizing the spontaneous spreading and wetting of the wall of the self-wetting fluid, the shaped micro-fins to promote bubble nucleation, maintain the liquid film, and the jet impact to break up large bubbles / vapor films, can effectively solve the problems of traditional heat dissipation, such as the difficulty of nucleation in jet boiling on smooth surfaces and the deterioration of heat transfer due to bubble merging and covering the heating surface, and significantly improve the boiling heat transfer performance.

[0034] 4. After the fluid vertically impacts the heating base plate, it does not need to flow horizontally for a long distance to the outlet. Instead, it flows in vertically, briefly passes through the interval distance of a horizontal inlet and outlet channel, and then flows out of the channel vertically. The bubbles on the base plate are not easy to generate large bubbles / vapor films. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly describes the drawings required for the specific embodiments or the description of the prior art. Similar elements or parts are generally identified by similar reference numerals throughout the drawings. Elements or parts in the drawings are not necessarily drawn to scale.

[0036] Figure 1 An exploded view of a high-speed auxiliary nozzle in cooperation with a special-shaped micro-rib jet microchannel according to an embodiment of the present invention;

[0037] Figure 2 Schematic diagram of the bottom plate structure of an embodiment of the present invention;

[0038] Figure 3 is a cross-sectional schematic diagram of a bottom plate and an intermediate plate according to an embodiment of the present invention;

[0039] Figure 4 Schematic diagram of the local structure of various special-shaped micro-ribs according to an embodiment of the present invention;

[0040] Figure 5 This is a schematic diagram of the local dimensions of a cylindrical double-slit special-shaped micro-rib according to an embodiment of the present invention;

[0041] Figure 6 This is a schematic diagram of the structure of the intermediate plate according to an embodiment of the present invention;

[0042] Figure 7 Schematic cross-sectional view of a unit nozzle-high-speed auxiliary nozzle according to an embodiment of the present invention;

[0043] Figure 8 This is a schematic diagram of the dimensions of a unit nozzle-high-speed auxiliary nozzle according to an embodiment of the present invention;

[0044] Figure 9 Schematic diagram of a unit step nozzle-high-speed auxiliary nozzle according to an embodiment of the present invention;

[0045] Reference numerals:

[0046] 1- bottom plate, 10- special-shaped micro-rib, 19- enclosure plate, 2- middle plate, 21- micro-channel inlet slot, 22- micro-channel outlet slot, 23- nozzle, 24- high-speed auxiliary nozzle, 3- top cover plate. DETAILED DESCRIPTION

[0047] The following embodiments of the technical solution of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention and are therefore only examples and are not intended to limit the scope of protection of the present invention.

[0048] It should be noted that, unless otherwise specified, the technical or scientific terms used in this application should have the common meanings understood by those skilled in the art to which the present invention belongs.

[0049] Example

[0050] Research has shown that micro-rib structures can enhance heat transfer by promoting boiling bubble nucleation and maintaining a liquid film on the wall. The mechanism is that the microstructure reduces surface energy, and micro-ribs with a special shape exhibit more dramatic surface energy changes, which facilitates bubble nucleation. Furthermore, a suitable micro-rib array also helps maintain the liquid film on the wall, facilitating boiling phase change heat transfer.

[0051] To break up large bubbles and vapor films, the inventors discovered through research that jet impingement heat exchange requires a high jet inlet velocity to achieve effective cooling, typically requiring a very small inlet nozzle diameter. In particular, for microchannel jet impingement heat exchange, the size of a single microchannel currently used in engineering practice is typically less than 1 mm, necessitating a jet nozzle diameter less than 1 mm. Furthermore, jet impingement can also utilize high-speed jets to break up large bubbles and vapor films, further demanding smaller nozzle sizes and suitable nozzle structures.

[0052] From the above, it can be seen that by designing a smaller nozzle diameter, a suitable nozzle structure and a micro-fin structure array, it is expected to simultaneously achieve the promotion of boiling bubble nucleation, wall liquid film maintenance and large bubble / vapor film breaking in high-heat jet microchannel flow boiling heat transfer.

[0053] In view of the above research findings, this embodiment provides a high-speed auxiliary nozzle for chip heat dissipation in conjunction with a special-shaped micro-fin jet microchannel, such as Figure 1 As shown, it consists of a base plate 1 with a free-form micro-fin array, an intermediate plate 2 with a nozzle-high-speed auxiliary nozzle structure, and a top cover plate 3. The coolant fluid flows in from the nozzle-high-speed auxiliary nozzle on the bottom surface of the multiple parallel microchannels in the intermediate plate, vertically impacts the shaped micro-fin base plate, absorbs the heat generated by the base plate, and then flows vertically to the multiple parallel microchannel outlets in the intermediate plate.

[0054] A bottom plate 1 having a free-form micro-rib array, such as Figure 2 As shown, the bottom plate 1 is provided with an array of a plurality of free-shaped micro-ribs 10, and the bottom plate is enclosed by a surrounding plate 19. Figure 3As shown, the top of the free-shaped micro-rib is not in direct contact with the middle plate 2, and a gap g is left in the middle to provide space for gas expansion after boiling phase change. Preferably, the ratio x of the gap g and the depth H of the bottom plate inner wall satisfies:

[0055] x=g / H≤0.3 (1)

[0056] From the above formula, it can be seen that for microchannels of different sizes, the gap g should increase with the increase of the bottom plate inner wall depth H, and the ratio x of the gap g and the bottom plate inner wall depth H should be controlled to be always less than or equal to 0.3. This can ensure that the gap between the top of the free-shaped micro-rib and the middle plate will not be too large, and prevent the small bubbles after nucleation from passing through the top of the micro-rib and merging with the bubbles generated by the adjacent micro-ribs to form large bubbles covering the heating surface.

[0057] For the free-form micro-rib 10, in some embodiments, it can be as follows Figure 4 The illustrated single-slit cylindrical irregular micro-ribs 11, double-slit cylindrical irregular micro-ribs 12, cylindrical double-slit cylindrical irregular micro-ribs 13, single-slit square column irregular micro-ribs 14, double-slit square column irregular micro-ribs 15, cylindrical double-slit square column irregular micro-ribs 16, or other irregularly shaped structures similar to the present invention. The aforementioned free-shaped irregular micro-rib structures have abundant surface energy mutation points, which can promote fluid bubble nucleation; the slits within the irregular micro-ribs help maintain the liquid film, which is beneficial for improving boiling heat transfer performance. In specific embodiments, one or more of the aforementioned free-shaped irregular micro-ribs can be disposed on the base plate.

[0058] For the slit design inside the special-shaped micro-rib, such as Figure 5 As shown, taking the cylindrical double-slit cylindrical special-shaped micro-rib 13 as an example, the ratio m of the slit gap s to the cylinder major diameter D, and the ratio n of the cylinder minor diameter d to the cylinder major diameter D, respectively satisfy:

[0059] m=s / D≤0.2 (2)

[0060] n=d / D≤0.3 (3)

[0061] As can be seen from the above formula, the ratio (m) of the slit gap (s) to the cylinder's major diameter (D) is always less than or equal to 0.2. This ensures that the slit gap (s) is not too large, ensuring that the capillary force within the gap is strong enough to lock and maintain the liquid film and prevent dry burning of the wall surface. Furthermore, the ratio (n) of the cylinder's minor diameter (d) to the cylinder's major diameter (D) is always less than or equal to 0.3. This ensures that the hollow portion of the cylinder is not too large, preventing bubbles from nucleating within the large hollow structure and forming large bubbles that cover the heated surface, causing a rapid increase in wall temperature.

[0062] The middle plate 2 with nozzle-high-speed auxiliary nozzle structure, such as Figure 6As shown, the middle plate 2 includes multiple parallel microchannel inlet slots 21 and multiple parallel microchannel outlet slots 22. The bottom of the microchannel inlet slots is equipped with multiple nozzles 23 arranged in an array, with a high-speed auxiliary nozzle 24 of smaller diameter spaced between every two nozzles 23. The high-speed auxiliary nozzle 24 is based on the shape of the nozzle 23, but the latter half of the nozzle 23 is designed as a concave-convex structure, so that the diameter at the inlet of the high-speed auxiliary nozzle is the same as the nozzle diameter, and the diameter at the outlet is smaller than the nozzle diameter. The cross-section of the inlet and outlet microchannels of the middle plate perpendicular to the flow direction is rectangular or square; the shape of the nozzle is preferably circular, but can also be elliptical, square, or other commonly used shapes.

[0063] Unlike traditional microchannel heat exchangers where the nozzles are directly arranged in the inlet manifold, this embodiment first evenly divides the inlet fluid through multiple parallel microchannels, and then sprays it toward the microchannel base plate through the nozzle and the height auxiliary nozzle. This design can further improve the uniformity of fluid distribution. After the fluid in this embodiment vertically impacts the heating base plate, the fluid does not need to flow horizontally for a long distance to the outlet. Instead, it flows in vertically and then briefly passes through a horizontal inlet and outlet channel before flowing vertically out of the channel. Therefore, it is not easy for the bubbles on the base plate to generate large bubbles / vapor films, and there is no need to worry about the problem of a large amount of fluid in the traditional microchannel needing to flow horizontally for a long distance to the outlet after absorbing the heat from the base plate. In particular, in some embodiments, the inlet and outlet channels and nozzle array of the free-shaped micro-rib array and the intermediate plate can be expanded according to the size of the heat dissipation area, and can be widely used in large-area chip cooling and heat dissipation.

[0064] like Figure 7 As shown, the depth h of the microchannel inlet groove 21 is ≤ 1 mm, and the ratio y of the length l0 of the nozzle 23 and the thickness L of the intermediate plate 2 satisfies:

[0065] y=l0 / L≤0.6 (4)

[0066] As can be seen from the above formula, controlling the depth of the microchannel inlet groove 21 to be less than or equal to 1 mm ensures that the flow path is always a microchannel, thereby improving the flow and heat transfer effect. This is because when the microchannel size is ≤1 mm, microchannels have a significant advantage over conventional channels in terms of flow and heat transfer. Secondly, controlling the ratio of the nozzle length to the intermediate plate thickness to be less than or equal to 0.6 prevents the plate where the nozzle is located from being too thin to withstand the vibration caused by the high-speed jet flow.

[0067] The high-speed auxiliary nozzle is mainly used to destroy large bubbles or vapor films. The diameter of its outlet can theoretically be infinitely small, but in practice it is greater than or equal to 10 microns according to the machining capabilities. In actual applications, the thickness of the intermediate plate is usually several millimeters to several centimeters, and when the nozzle diameter is tens of microns, the aspect ratio of the nozzle increases rapidly. For example, when the thickness of the plate where the nozzle is located is 5 mm and the nozzle diameter is 0.1 mm, the aspect ratio reaches as high as 50. This large aspect ratio through-hole not only brings challenges to manufacturing and processing, but also causes a sharp increase in the pressure drop of the fluid at the inlet section, which is obviously not conducive to jet injection heat exchange. For this reason, the present embodiment designs a high-speed auxiliary nozzle with a concave-convex structure in the second half of the conventional nozzle. This design not only reduces the aspect ratio of the auxiliary nozzle and facilitates processing, but also has the advantage of reducing the flow pressure drop and pump work in the jet inlet section. The following method is used to determine the length and aspect ratio of the second half of the high-speed auxiliary nozzle:

[0068] like Figure 8 As shown, assuming that the density of the fluid is , fluid with the same volume flow rate V flows into nozzle 23 and high-speed auxiliary nozzle 24 respectively. The diameter of the first half of high-speed auxiliary nozzle 24 is d1, the length is l1, and the friction coefficient is f1, while the diameter of the second half is d2, the length is l2, and the friction coefficient is f2. Since the friction loss of the fluid flowing through the local constriction is very small compared to the loss in the main pipeline, this loss can be ignored. Assuming that the diameter of nozzle 23 is d0 and the length is l0, the pressure drop of the fluid in high-speed auxiliary nozzle 24 is the sum of the pressure drops in the first and second halves:

[0069] (5)

[0070] in: , , ,but

[0071] (6)

[0072] The pressure drop of the fluid in the nozzle 23 is:

[0073] (7)

[0074] Therefore, the pressure drop ratio z of the fluid in the high-speed auxiliary nozzle 24 and the nozzle 23 satisfies:

[0075] (8)

[0076] Among them, the aspect ratio r of the rear half of the auxiliary nozzle is defined as:

[0077] r=l2 / d2(9)

[0078] The aspect ratio r of the second half of the auxiliary nozzle shows that, although the diameter d2 of the auxiliary nozzle is very small, its length l2 is less than l0. Therefore, the aspect ratio of the second half of the auxiliary nozzle is smaller than that of the structure without the auxiliary nozzle, which is very beneficial for machining. Its specific value can be adjusted according to the pressure drop requirements within the high-speed auxiliary nozzle 24 and the nozzle 23, as well as the machining capability.

[0079] In some embodiments, when the thickness of the middle plate where the nozzle is located is very large, in order to manufacture a high-speed auxiliary nozzle, a stepped aperture structure can be used for processing. A typical stepped aperture structure is as follows: Figure 9 As shown in FIG, a four-level pore size structure is adopted. When necessary, the number of pore size gradients can be further increased.

[0080] The nozzle-high-speed auxiliary nozzle array structure designed in this embodiment replaces the low inlet flow velocity of the conventional manifold structure microchannel, significantly increasing the inlet flow velocity. High flow velocity can improve convective heat transfer performance, while the high flow velocity of the auxiliary nozzle can inhibit the merging of boiling phase transition bubbles into large bubbles / vapor films, which deteriorates heat transfer performance. Furthermore, the nozzle-high-speed auxiliary nozzle array does not have a high-speed auxiliary nozzle designed on every nozzle. This is because high flow velocity is not conducive to fluid bubble nucleation, thus requiring a relatively low nozzle inlet flow velocity. Wall bubbles corresponding to relatively low nozzle inlet flow velocity nucleate and grow outwards. High-speed auxiliary nozzles next to the nozzle can play a role in disrupting bubble growth by using high jet velocities. On the other hand, if every nozzle is designed as a high-speed auxiliary nozzle, the flow pressure drop and pump work at the jet inlet section will increase. However, arranging high-speed auxiliary nozzles at intervals can reduce the flow pressure drop.

[0081] In a specific embodiment, the base plate, middle plate, and cover plate of the microchannel are made of semiconductor materials, such as common semiconductor materials such as silicon and germanium, metals such as copper, aluminum, and stainless steel, precious metals such as titanium and tungsten, or high thermal conductivity materials such as nickel-based alloys. Furthermore, the middle plate and cover plate can also be made of high-temperature resistant polymer materials, such as polyetheretherketone (PEEK), polycarbonate (PC), and polymethyl methacrylate (PMMA).

[0082] The coolant of the present invention is preferably a self-wetting fluid, such as n-butanol solution, or a common low-boiling point electronic fluoride liquid such as HFE7100, HFE7000, FC72, etc., or deionized water, etc.

[0083] By adopting the technical solution of this embodiment, the nozzle-high-speed auxiliary nozzle array and the free-shaped micro-fin array are coordinated, and at the same time, a fluid with self-wetting function is preferably used. By synergistically utilizing the spontaneous spreading and wetting of the wall of the self-wetting fluid, the special-shaped micro-ribs to promote bubble nucleation, maintain the liquid film and the jet impact to break up large bubbles / vapor film, it can effectively solve the difficult problems of traditional large-scale smooth surface jet boiling that are difficult to nucleate and the bubbles merging and covering the heating surface to deteriorate heat transfer, and significantly improve the boiling heat transfer performance.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention.

Claims

1. A high-speed auxiliary nozzle cooperates with a special-shaped micro-fin jet microchannel, characterized in that: include: bottom plate, middle plate and top cover plate; The bottom plate is provided with a plurality of free-shaped special-shaped micro-ribs distributed in an array, with a gap between the top of the free-shaped special-shaped micro-ribs and the middle plate; the bottom plate is enclosed by a surrounding plate; the free-shaped special-shaped micro-ribs include: single-slit cylindrical special-shaped micro-ribs, double-slit cylindrical special-shaped micro-ribs, cylindrical double-slit cylindrical special-shaped micro-ribs, single-slit square column special-shaped micro-ribs, double-slit square column special-shaped micro-ribs and / or cylindrical double-slit square column special-shaped micro-ribs; The middle plate includes a plurality of microchannel inlet slots and a plurality of microchannel outlet slots. The bottom of the microchannel inlet slots is provided with a plurality of nozzles and a plurality of high-speed auxiliary nozzles. The diameter of the inlet of the high-speed auxiliary nozzle is the same as that of the nozzle, and the diameter of the outlet is smaller than that of the nozzle. The nozzles and the high-speed auxiliary nozzles are arranged at intervals. The top cover is arranged above the middle plate.

2. The high-speed auxiliary nozzle and special-shaped micro-fin jet microchannel according to claim 1 is characterized in that: The ratio x of the gap to the depth of the bottom plate inner wall satisfies: x=g / H≤0.3 In the above formula, g represents the gap between the top of the free-shaped micro-rib and the middle plate, and H represents the depth of the inner wall of the bottom plate.

3. The high-speed auxiliary nozzle and special-shaped micro-fin jet microchannel according to claim 1 is characterized in that: The slit gap and cylinder diameter of the cylindrical double-slit special-shaped micro-ribs satisfy the following requirements: m=s / D≤0.2,n=d / D≤0.3 In the above formula, m represents the ratio of the slit gap to the cylinder's major circle diameter, n represents the ratio of the cylinder's minor circle diameter to the cylinder's major circle diameter, s represents the slit gap, D represents the cylinder's major circle diameter, and d represents the cylinder's minor circle diameter.

4. The high-speed auxiliary nozzle and special-shaped micro-fin jet microchannel according to claim 1, characterized in that: The ratio y of the nozzle length to the intermediate plate thickness satisfies: y=l0 / L≤0.6 In the above formula, l0 represents the length of the nozzle and L represents the thickness of the middle plate.

5. The high-speed auxiliary nozzle and special-shaped micro-fin jet microchannel according to claim 1, characterized in that: The high-speed auxiliary nozzle includes a front half and a rear half structure; the front half structure is consistent with the structure of the same part of the nozzle; the rear half is a concave-concave structure, and its diameter is smaller than the diameter of the same part of the nozzle.

6. The high-speed auxiliary nozzle and special-shaped micro-fin jet microchannel according to claim 5, characterized in that: The length and aspect ratio of the rear half of the high-speed auxiliary nozzle are determined based on the high-speed auxiliary nozzle and the fluid pressure drop requirements within the nozzle. The fluid pressure drop requirements include: In the above formula, Indicates the pressure drop of the fluid in the high-speed auxiliary nozzle, Indicates the pressure drop of the fluid in the nozzle; the diameter of the front half of the high-speed auxiliary nozzle is d1, the length is l1, and the friction coefficient is f1; the diameter of the rear half is d2, the length is l2, and the friction coefficient is f2; the diameter of the nozzle is d0, and the length is l0; The aspect ratio of the rear half of the high-speed auxiliary nozzle is r=l2 / d2.

7. The high-speed auxiliary nozzle and special-shaped micro-fin jet microchannel according to claim 5, characterized in that: The second half includes multiple sections of concave and convex structures, and the diameter of each section of the concave and convex structure decreases from top to bottom.

8. The high-speed auxiliary nozzle and special-shaped micro-fin jet microchannel according to claim 1, characterized in that: The multiple inlet grooves and multiple outlet grooves of the microchannel are arranged in parallel on an intermediate plate. The inlet fluid is first evenly distributed through the multiple parallel microchannel grooves, and then sprayed toward the microchannel bottom plate through the nozzle and the height auxiliary nozzle. Then, after passing through the interval distance of a horizontal inlet and outlet channel, it flows vertically to the multiple parallel microchannel outlets and flows out.

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