Spiral micro-channel cooling pipe combined with impact jet flow

Abstract

The invention relates to a spiral micro-channel cooling pipe combined with impact jet flow. The spiral micro-channel cooling pipe comprises a pipe body, a channel in the center of the pipe body is a center flow guide channel, a spiral micro-channel is arranged in the pipe body and surrounds the periphery of the center flow guide channel, a coolant inlet is formed in one end of the center flow guide channel, impact holes are formed in the periphery of the center flow guide channel, and the center flow guide channel is communicated with the spiral micro-channel through the impact holes. An annular flow collecting cavity is formed in the end, opposite to the coolant inlet, of the pipe body, the tail ends of the spiral micro-channels communicate with the annular flow collecting cavity, and a coolant outlet is formed in the annular flow collecting cavity. The invention discloses a spiral micro-channel cooling pipe combined with impingement jet flow, which realizes an efficient, uniform and low-energy-consumption heat dissipation effect through the synergistic effect of periodic impingement cooling and micro-channel rotational flow, and is suitable for the fields of electronic equipment, industrial equipment and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of thermal management and relates to a spiral microchannel cooling tube combined with an impingement jet. Background Art

[0002] With the continuous development of electronic and industrial equipment, their power density and heat flux density are increasing. Heat dissipation has become a key factor restricting the performance improvement and stable operation of equipment. For example, the energy consumption of data centers has accounted for 1% to 3% of the total global energy consumption, and the data center market in the Asia-Pacific region has grown most significantly. In high-performance electronic devices, such as CPUs and GPUs, the local heat density can even exceed 1kW / cm 2 , traditional heat dissipation technology is difficult to meet the needs. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention proposes a spiral microchannel cooling tube combined with an impingement jet. The cooling tube achieves efficient, uniform and low-energy heat dissipation effect through the organic combination of spiral microchannels and impingement jet devices, and is suitable for electronic equipment, industrial equipment and other fields.

[0004] The technical solution of the present invention to solve the above problems is: a spiral microchannel cooling tube combined with impingement jet, which is special in that:

[0005] Includes tube body;

[0006] The channel in the center of the tube body is a central flow guide channel, a spiral microchannel is provided in the tube body, the spiral microchannel surrounds the periphery of the central flow guide channel, an impact hole is provided on the periphery of the central flow guide channel, and the central flow guide channel is connected to the spiral microchannel through the impact hole;

[0007] One end of the central flow guide channel is a coolant inlet, and the end of the tube body opposite to the coolant inlet is provided with an annular collecting cavity. The end of the spiral microchannel is connected to the annular collecting cavity, and a coolant outlet is provided on the annular collecting cavity.

[0008] Furthermore, there are multiple spiral microchannels, which are evenly distributed around the central flow guiding channel; the length of the central flow guiding channel is 0.7 to 0.9L, where L is the length of the tube body.

[0009] Furthermore, the section from the coolant inlet to the starting end of the spiral microchannel on the tube body is the inlet section, and the length N of the inlet section is 2 to 4 times R0, where R0 is the diameter of the central guide channel.

[0010] Furthermore, the above-mentioned impact holes are perpendicular to the axial direction of the central guide channel and are evenly distributed along the circumference of the central guide channel in a staggered array. The cooling medium is ejected outward through the impact holes of the impact jet layer, forming a high-speed jet that vertically impacts the cooled surface, thereby achieving rapid cooling of local high heat flux density.

[0011] Furthermore, the jet coverage density can be controlled by the array distribution of the impact holes. The hole spacing d is set to 1 to 4 impact holes according to each spiral period. The aperture r2 of the impact hole is required to be smaller than the inner diameter of the spiral microchannel and is 0.5 to 1 times the impact hole height to ensure the balance between structural strength and jet penetration. The impact hole height is (R1-R0), where R1 is the inner diameter of the spiral microchannel.

[0012] Furthermore, the above-mentioned spiral microchannel is a spiral flow channel etched on the inner wall of the tube body. The working fluid that completes the impact cooling enters the spiral microchannel and is induced by the spiral structure to generate continuous vortex, which peels off the thermal boundary layer through the centrifugal effect and extends the effective heat exchange path.

[0013] Furthermore, the spiral angle θ of the spiral microchannel is 25° to 75°; the cross-sectional aspect ratio of the spiral microchannel is 1.5:1 to 2:1, which enhances the secondary flow intensity. The cross-section of the spiral microchannel can be rectangular, trapezoidal, circular, or the like.

[0014] Furthermore, the length M of the annular collecting cavity is 0.5 to 1 times the pitch of the spiral microchannel to ensure a smooth transition of the flow pattern. The inner diameter R1 of the annular collecting cavity is consistent with the inner diameter of the spiral microchannel, and the outer diameter R2 of the annular collecting cavity is consistent with the outer diameter of the spiral microchannel.

[0015] Furthermore, the coolant outlet is a tubular outlet perpendicular to the side wall of the annular collecting cavity, which discharges the final working medium of the enhanced heat exchange system.

[0016] Furthermore, the ratio of the inner diameter r1 of the coolant outlet to the equivalent diameter of the spiral microchannel is 1:1 to 2:1, matching the flow expansion requirements. In addition, it can be set to a gradually widening structure with a gradually widening angle of 8° to 12° to avoid flow separation while maximizing pressure recovery.

[0017] Advantages of the present invention:

[0018] The present invention discloses a spiral microchannel cooling tube combined with an impinging jet. Microchannel cooling technology has become one of the effective ways to solve the problem of high heat flux density heat dissipation due to its efficient flow and heat transfer performance. The size of the microchannel is usually in the micron to millimeter level, which makes the surface area to volume ratio of the fluid in the channel large, and forms a laminar flow in the channel, so that heat can be quickly transferred to the fluid, thereby achieving efficient heat dissipation. Among them, the spiral microchannel, due to its unique spiral shape, can provide a larger surface area in a limited space, while increasing the turbulent flow of the fluid, helping to break the boundary layer and make the heat transfer between the fluid and the wall more sufficient; based on the heat dissipation advantage of impinging cooling in local hot spots, the flow mixing in the channel is enhanced, and a spiral microchannel cooling tube combined with an impinging jet is designed to enhance the local heat exchange of the spiral microchannel and improve temperature uniformity; the present invention realizes a multi-stage enhanced heat transfer mechanism of "jet injection-swirl maintenance-boundary layer dynamic control" by coupling the impinging jet with the spiral flow to achieve efficient and uniform heat dissipation effect, which can be widely used in high heat flux density electronic equipment, industrial equipment and other fields, effectively improving the operating efficiency and stability of the equipment and extending its service life. In addition, the cooling pipe has the advantages of strong scalability and stable system performance. It can be customized and optimized according to different heat dissipation requirements to meet diverse application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the overall structure of the spiral microchannel cooling tube proposed in the present invention;

[0020] Figure 2 The left side view shows the spiral microchannel cooling tube, and the right side shows the overall structure of the fluid domain without the tube.

[0021] Figure 3 A partial structural view of a spiral cycle of a spiral microchannel cooling tube. The left side shows the distribution of impact holes, and the right side shows a schematic diagram of the spiral microchannel combined impact hole structure.

[0022] Figure 4 This is the main view of the spiral microchannel cooling tube;

[0023] Figure 5 The left side view shows the overall dimensions of the spiral microchannel cooling tube, and the right side shows the microchannel structure dimensions of a single spiral period without the tube body.

[0024] Figure 6 The coolant flow diagram in a single spiral microchannel branch.

[0025] 1. Tube body, 2. Coolant inlet, 3. Central guide channel, 4. Impact hole, 5. Spiral microchannel, 6. Annular collecting cavity, 7. Coolant outlet. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention for which protection is claimed, but merely represents selected embodiments of the present invention.

[0027] See attached Figures 1-6 The present invention proposes a spiral microchannel cooling tube combined with an impact jet, comprising a tube body 1; the channel in the center of the tube body 1 is a central flow guide channel 3, a spiral microchannel 5 is provided in the tube wall of the tube body 1, the spiral microchannel 5 surrounds the periphery of the central flow guide channel 3, one end of the central flow guide channel 3 is a coolant inlet 2, and the tube body 1 is provided with an annular collecting cavity 6 at the end opposite to the coolant inlet 2. An impact hole 4 is provided on the periphery of the central flow guide channel 3, and the central guide channel 3 is connected to the spiral microchannel 5 through the impact hole 4. The end of the spiral microchannel 5 is connected to the annular collecting cavity 6, and a coolant outlet 7 is provided on the annular collecting cavity 6. The annular collecting cavity 6 is used to collect the outflowing working fluid after heat exchange of each branch spiral microchannel.

[0028] After being injected into the central flow channel 3, the cooling fluid forms a high-speed jet through the impact hole 4, which vertically impacts the high-heat-flux surface. This generates strong turbulence and shear forces, rapidly removing heat and achieving localized, instantaneous heat transfer enhancement. The impacted fluid then enters the spiral microchannel 5, where the spiral geometry induces a secondary vortex. This centrifugal effect continuously strips away the thermal boundary layer and extends the effective heat transfer path. The microchannel's spiral structure increases heat dissipation area and optimizes fluid distribution, improving heat dissipation efficiency while reducing pressure drop. This design offers excellent spatial adaptability and structural compactness.

[0029] Specifically, the tube body 1 is a cylindrical, high-strength metal body. Its wall forms the outer heat transfer surface of the spiral microchannel, serving as the main load-bearing structure of the device, providing mechanical strength support and flow channel sealing. The central guide channel 3 is used to introduce coolant and distribute its flow. The inner diameter and length of the central guide channel 3 must be precisely calculated based on the cooling requirements and system pressure to ensure that the coolant can enter the spiral microchannel at an appropriate speed and flow rate.

[0030] The impact hole connects the central tube and the spiral microchannel, directing the coolant onto the heat source surface in the form of a high-speed jet, rapidly removing a large amount of heat and achieving localized enhanced heat transfer. The impact hole diameter must take into account the size of the spiral microchannel to prevent excessive flow resistance within the channel.

[0031] The spiral microchannels are arranged in a spiral pattern, with multiple continuous coils. The inner and outer diameters of each coil can be optimized based on heat dissipation requirements. These microchannels increase the heat dissipation area and optimize fluid distribution, meeting the heat dissipation requirements in high-heat flux density scenarios.

[0032] When the spiral microchannel cooling tube is operating, the coolant in the spiral microchannel flows in an annular pattern. The centripetal acceleration creates a high velocity region at the outer ring of the tube, enhancing the heat dissipation performance when the heat source is the outer ring of the spiral microchannel. The impinging jet passing through the impact hole forms a stagnation zone on the wall, combining with the spiral flow to enhance flow and heat transfer. The jet and the spiral flow direction form a shear force, effectively suppressing boundary layer flow separation. The impact and entrainment caused by the jet will form two additional secondary vortices, which then gradually dissipate. The uniform layout of the impinging jet further promotes uniform heat transfer and avoids local overheating.

[0033] In some embodiments provided herein, the spiral microchannels 5 are multiple and evenly distributed around the periphery of the central flow channel 3. The central flow channel 3 is located at the device's axial center, and the working fluid flows axially along the central flow channel 3, forming a uniform initial flow field. The length of the central flow channel 3 is 0.7 to 0.9L, where L is the length of the tube body 1.

[0034] Furthermore, the wall thickness of the tube body 1 is positively correlated with its diameter, ensuring that the structural rigidity matches the thermal expansion.

[0035] In some embodiments provided by the present invention, see Figure 4 The section from the coolant inlet 2 to the starting end of the spiral microchannel 5 on the tube body 1 is the inlet section, and the length N of the inlet section is 2 to 4 times R0, where R0 is the inner diameter of the central guide channel 3.

[0036] In some embodiments provided by the present invention, see Figures 1-6 The impact holes 4 are perpendicular to the axis of the central flow channel 3 and are evenly distributed around the circumference of the central flow channel 3 in a staggered array. The cooling fluid is ejected outward through the micropores of the impact jet layer, forming a high-speed jet that perpendicularly impacts the cooled surface, achieving rapid cooling at a localized high heat flux density.

[0037] In some embodiments provided by the present invention, see Figure 5 The jet coverage density can be controlled by the hole array distribution. 1 to 4 impact holes are set in each spiral period. The aperture r2 of the impact hole 4 is required to be smaller than the inner diameter of the spiral microchannel 5 and is 0.5 to 1 times the height of the impact hole 4 to ensure the balance between structural strength and jet penetration. The height of the impact hole 4 is (R1-R0), and R1 is the inner diameter of the spiral microchannel 5.

[0038] In some embodiments provided by the present invention, the outer spiral microchannel 5 is a spiral flow channel etched on the inner wall of the tube body 1. The working fluid that completes the impact cooling enters the spiral microchannel and is induced by the spiral structure to generate continuous vortex, which peels off the thermal boundary layer through the centrifugal effect and extends the effective heat exchange path.

[0039] For further information, see Figure 5 The spiral angle θ of the spiral microchannel 5 is 25° to 75°; the channel cross-section depth-to-width ratio of the spiral microchannel 5 is 1.5:1 to 2:1, which enhances the secondary flow intensity. In addition, the channel cross-section can be rectangular, trapezoidal, circular, and other shapes.

[0040] Furthermore, the number of branches of the spiral microchannel can be changed according to heat exchange requirements and flow resistance limitations.

[0041] In some embodiments provided by the present invention, the axial length M of the cavity is 0.5 to 1 times the pitch of the spiral microchannel to ensure a smooth transition of the flow state. The inner diameter R1 is consistent with the inner diameter of the spiral tube, and the outer diameter R2 is consistent with the outer diameter of the spiral tube.

[0042] In some embodiments provided by the present invention, see Figure 4 The coolant outlet 7 is a tubular outlet perpendicular to the annular collecting cavity 6, which will discharge the final working medium that completes the enhanced heat exchange out of the system.

[0043] Specifically, the ratio of the inner diameter r1 of the coolant outlet 7 to the equivalent diameter of the spiral microchannel is 1:1 to 2:1, matching the flow expansion requirements. In addition, the coolant outlet 7 can also be set to a gradually widened structure with a gradually widening angle of 8° to 12° to avoid flow separation while maximizing pressure recovery.

[0044] The core principle of the cooling structure coupled with impinging jets and spiral microchannels proposed in the present invention to enhance heat exchange is to achieve dynamic destruction of the thermal boundary layer and efficient coverage of the heat transfer surface through the synergistic effect of multi-stage flow patterns.

[0045] Specifically (see Appendix Figure 6 ), taking a single spiral microchannel branch as an example to illustrate the coolant flow direction, the cooling medium is axially injected from the central guide channel 3 to form a uniform and stable initial flow field (C1). When the cooling medium is ejected outward through the circumferentially distributed impact holes 4, a high-speed, dense micro-jet array (C2) is formed, which vertically impacts the cooled surface and enters the spiral microchannel 5.

[0046] This shock has a double reinforcing effect:

[0047] First, the high velocity (C3) in the core area of the jet directly penetrates the stagnation boundary layer of traditional convective heat transfer, rapidly entraining and separating the high-temperature fluid near the wall, allowing the cold fluid to come into direct contact with the hot surface, significantly enhancing the intensity of local convective heat transfer.

[0048] Secondly, the radial wall jet (C4) formed by the impinging jet spreading on the wall induces strong turbulent pulsation through shearing action, further disturbing the thermal boundary layer and enhancing the heat exchange in the near-wall region.

[0049] The working fluid after the impact cooling is mixed with the preceding fluid flowing in the spiral microchannel 5, that is, the working fluid from the upstream spiral section (C5) at the impact outlet, and then merges to form a spiral flow (C6).

[0050] At the same time, the periodic injection of the impact fluid forms unsteady disturbances in the spiral microchannel, inducing unstable waves and leading to intermittent rupture of the thermal boundary layer.

[0051] The mechanism of spiral motion enhancing heat transfer is that, on the one hand, centrifugal force continuously throws the low-temperature working fluid toward the high heat flux wall outside the channel, forming forced wall flow and extending the effective contact time between the working fluid and the heat transfer surface; on the other hand, the lateral momentum exchange caused by the swirl continuously destroys the formed thermal boundary layer, making the wall temperature distribution tend to be uniform.

[0052] Finally, the working medium (C7) that completes the heat exchange in the spiral microchannel moves along the spiral flow channel to the terminal outlet section, and multiple flow branches converge into the annular collecting cavity 6.

[0053] At this time, the annular cavity regularizes the flow of the microchannel fluid with uneven flow state, uneven temperature distribution and residual swirl energy, and discharges the rectified working medium (C8) through the tubular outlet.

[0054] In summary, this invention couples impingement cooling with spiral flow to create an enhanced heat transfer system characterized by "jet injection, swirl maintenance, and dynamic boundary layer control." This design not only overcomes the technical bottleneck of traditional cooling structures in high-temperature environments but also achieves synergistic optimization of heat dissipation and energy consumption characteristics through the stepped utilization of flow energy, providing an innovative solution for compact thermal management of high-heat-flux equipment.

[0055] The above descriptions are merely embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied to other related system fields, are also included in the scope of protection of the present invention.

Claims

1. A spiral microchannel cooling tube combined with impingement jet, characterized in that: Includes tube body(1); The channel at the center of the tube body (1) is a central flow guiding channel (3), a spiral microchannel (5) is provided in the tube body (1), the spiral microchannel (5) surrounds the periphery of the central flow guiding channel (3), one end of the central flow guiding channel (3) is a coolant inlet (2), an impact hole (4) is provided on the periphery of the central flow guiding channel (3), and the central flow guiding channel (3) is connected to the spiral microchannel (5) through the impact hole (4); An annular collecting cavity (6) is provided at one end of the tube body (1) relative to the coolant inlet (2), the end of the spiral microchannel (5) is communicated with the annular collecting cavity (6), and a coolant outlet (7) is provided on the annular collecting cavity (6).

2. The spiral microchannel cooling tube combined with impingement jet according to claim 1, characterized in that: The spiral microchannels (5) are multiple in number, and the multiple spiral microchannels (5) are evenly distributed around the central flow guiding channel (3); the length of the central flow guiding channel (3) is 0.7-0.9L, where L is the length of the tube body (1).

3. The spiral microchannel cooling tube combined with impingement jet according to claim 2, characterized in that: The section from the coolant inlet (2) to the starting end of the spiral microchannel (5) on the tube body (1) is an inlet section, and the length N of the inlet section is 2 to 4 times R0, where R0 is the inner diameter of the central guide channel (3).

4. The spiral microchannel cooling tube combined with impingement jet according to claim 3, characterized in that: The impact holes (4) are perpendicular to the axial direction of the central flow guiding channel (3) and are evenly distributed along the circumference of the central flow guiding channel (3) in a staggered array.

5. The spiral microchannel cooling tube combined with impingement jet according to claim 4, characterized in that: Each spiral period of the spiral microchannel (5) is provided with 1 to 4 impact holes. The aperture r2 of the impact hole (4) is required to be smaller than the inner diameter of the spiral microchannel (5) and is 0.5 to 1 times the height of the impact hole (4) to ensure a balance between structural strength and jet penetration. The height of the impact hole (4) is (R1-R0), where R1 is the inner diameter of the spiral microchannel (5).

6. The spiral microchannel cooling tube combined with impingement jet according to claim 1, characterized in that: The spiral microchannel (5) is a spiral flow channel etched on the wall of the tube body (1).

7. The spiral microchannel cooling tube combined with impingement jet according to claim 5, characterized in that: The spiral angle θ of the spiral microchannel (5) is 25° to 75°; the cross-sectional depth-to-width ratio of the spiral microchannel (5) is 1.5:1 to 2:1; and the cross-section of the spiral microchannel (5) is rectangular, trapezoidal, or circular.

8. The spiral microchannel cooling tube combined with impingement jet according to claim 7, characterized in that: The length M of the annular collecting cavity (6) is 0.5 to 1 times the pitch of the spiral microchannel (5), the inner diameter R1 of the annular collecting cavity (6) is equal to the inner wall diameter of the spiral microchannel (5), and the outer diameter R2 of the annular collecting cavity (6) is equal to the outer wall diameter of the spiral microchannel (5).

9. The spiral microchannel cooling tube combined with impingement jet according to claim 8, characterized in that: The coolant outlet (7) is a tubular outlet perpendicular to the side wall of the annular collecting cavity (6).

10. The spiral microchannel cooling tube combined with impingement jet according to claim 9, characterized in that: The ratio of the inner diameter r1 of the coolant outlet (7) to the equivalent diameter of the spiral microchannel (5) is 1:1 to 2:1.

Images