Diverging printed circuit board heat exchanger core and heat exchanger adapted for two-phase flow

Abstract

This application discloses a gradually expanding printed circuit board heat exchanger core and heat exchanger adapted to two-phase flow. It includes a cover plate, a bottom plate, a cold side plate layer, and a hot side plate layer. The cold side gradually expanding channel adopts a flow channel structure with progressively increasing width. The cross-sectional area of ​​the flow channel dynamically adapts to the volume change of the gas-liquid phase transition, reducing pressure drop fluctuations and bubble aggregation caused by gas phase expansion. The parallel layout of the diversion channel and the gradually expanding channel, combined with the porous structure of the inner wall, optimizes the uniformity of medium distribution and significantly improves flow stability through graded distribution and enhanced surface wettability. The hot side heat exchange channel incorporates turbulence ribs, which enhance convective heat transfer and phase change heat transfer by disrupting the thermal boundary layer and inducing turbulence. It supports heterogeneous working fluid combinations such as supercritical CO2-water and liquid hydrogen-liquid oxygen. This heat exchanger can improve heat exchange efficiency while reducing pressure drop, balancing compactness, reliability, and wide operating condition adaptability. It achieves optimized two-phase flow and efficient heat exchange, meeting the extreme heat exchange requirements of aerospace, new energy, and other fields.

Description

Technical Field

[0001] This application relates to the technical field of printed circuit board heat exchangers, and more particularly to a gradually expanding printed circuit board heat exchange core and heat exchanger adapted to two-phase flow. Background Technology

[0002] With the technological advancements in aerospace, petrochemical, and energy industries, heat exchange equipment faces increasingly stringent operating conditions, requiring more compact heat transfer efficiency under higher heat loads. This demand has driven the development of new, highly efficient, and compact heat exchange devices. Printed circuit board heat exchangers (PCHEs) have emerged as a new type of highly efficient and compact heat exchange device, significantly improving overall performance through a combination of microchannel structure design and advanced manufacturing processes. A key feature of this type of heat exchanger is the use of chemical etching to form sub-millimeter-level precision flow channels on the surface of a metal substrate, followed by integrated packaging of multi-level flow channel structures through diffusion welding technology. These structural characteristics give it high compactness parameters while maintaining structural stability under extreme conditions, including high-pressure and high-temperature environments. These technological breakthroughs provide crucial technical support for the lightweight and intensive development of industrial equipment.

[0003] Traditional PCHEs typically employ straight-channel or fixed-section flow channels for both hot and cold flow. However, in two-phase flow conditions (such as gas-liquid mixing), straight channels can easily lead to uneven flow, bubble aggregation, and increased pressure drop, thus affecting heat transfer efficiency. In particular, if the cold-side flow channel cannot adapt to changes in two-phase flow volume, it may cause localized drying or liquid film rupture, further exacerbating heat transfer degradation. Furthermore, traditional PCHEs are less capable of handling instantaneous high-power conditions such as liquid hydrogen flash evaporation and rapid supercritical carbon dioxide endothermization, making it difficult to maintain temperature stability under these conditions.

[0004] While some flow channel optimization designs exist in existing technologies (such as wavy and zigzag flow channels), they primarily target single-phase flow heat transfer and do not fully consider the dynamic characteristics of two-phase flow. Therefore, there is an urgent need for a printed circuit board heat exchanger specifically designed for two-phase flow, which can improve flow distribution and heat transfer performance through flow channel geometry optimization, and add corresponding structures to address the problem of instantaneous high-power operation. Summary of the Invention

[0005] In an exemplary embodiment of this application, a gradually expanding printed circuit board heat exchange core and heat exchanger adapted to two-phase flow are provided to improve the heat exchange efficiency and operational stability of two-phase flow through the synergistic effect of composite phase change material cover and base plate, graded gradually expanding channels, porous walls and enhanced heat transfer structure, while also taking into account temperature stability under instantaneous high temperature conditions.

[0006] This application provides a gradually expanding printed circuit board type heat exchange core adapted to two-phase flow, which includes a cover plate, a bottom plate, a cold side plate layer, and a hot side plate layer. The cold side plate layer and the hot side plate layer are respectively located between the cover plate and the bottom plate. The cold side plate layer and the hot side plate layer are alternately stacked in the vertical direction, and the cold side plate layer and the hot side plate layer are welded together.

[0007] Both the cover plate and the bottom plate include a substrate and a phase change layer. The phase change layer is formed inside the substrate and is filled with a phase change material.

[0008] The cold side plate layer includes a cold runner inlet, a branch channel, a diffuser channel, and a cold runner outlet. The cold runner inlet, the branch channel, the diffuser channel, and the cold runner outlet are all formed on the surface of the cold side plate layer. The cold runner inlet, the branch channel, the diffuser channel, and the cold runner outlet are sequentially connected. The medium enters from the cold runner inlet and flows out from the cold runner outlet via the branch channel and the diffuser channel. The number of diffuser channels is greater than the number of branch channels. The width of the diffuser channel gradually increases along the direction from the cold runner inlet to the cold runner outlet.

[0009] The hot side plate layer includes a hot runner inlet, an inlet branch channel, a heat exchange channel, an outlet branch channel, and a hot runner outlet. The hot runner inlet, the inlet branch channel, the heat exchange channel, the outlet branch channel, and the hot runner outlet are all formed on the surface of the hot side plate layer. The hot runner inlet, the inlet branch channel, the heat exchange channel, the outlet branch channel, and the hot runner outlet are sequentially connected. The medium enters from the hot runner inlet and flows through the inlet branch channel, the heat exchange channel, and the outlet branch channel before flowing out from the hot runner outlet. The heat exchange channel is provided with turbulence ribs inside.

[0010] Furthermore, the gradually expanding channel is arranged in parallel with the diversion channel.

[0011] Furthermore, the feature is that the plurality of the turbulence ribs are spaced apart along the extension direction of the heat exchange channel.

[0012] Furthermore, the number of the inlet diversion channel, the heat exchange channel, and the outlet diversion channel are equal.

[0013] Furthermore, a perforated structure is provided on the inner wall of the gradually expanding channel, and the inner diameter of the perforated structure gradually increases along the direction from the cold runner inlet to the cold runner outlet.

[0014] Furthermore, the width of the turbulence rib gradually increases in the direction from the end of the heat exchange channel near the inlet branch channel to the end of the heat exchange channel near the outlet branch channel.

[0015] Furthermore, the height of the turbulence rib is 20% of the height of the heat exchange channel.

[0016] Furthermore, the inlet branch channel is perpendicular to the heat exchange channel, and the outlet branch channel is perpendicular to the heat exchange channel.

[0017] Furthermore, the ratio of the diversion channel to the expanding channel is 1:2, 1:3, or 1:4.

[0018] This application also provides a gradually expanding printed circuit board heat exchanger adapted to two-phase flow, including the gradually expanding printed circuit board heat exchange core adapted to two-phase flow provided above.

[0019] The embodiments of this application have the following beneficial effects: The printed circuit board heat exchanger achieves two-phase flow optimization and efficient heat exchange through multi-structure collaborative design. The cold-side gradually expanding channel adopts a flow channel structure with progressively increasing width. The cross-sectional area of ​​the flow channel dynamically adapts to the volume change of the gas-liquid phase change, reducing pressure drop fluctuations and bubble aggregation caused by gas phase expansion. The parallel layout of the diversion channel and the gradually expanding channel, combined with the porous structure of the inner wall, optimizes the uniformity of medium distribution and significantly improves flow stability through graded distribution and enhanced surface wettability. The hot-side heat exchange channel incorporates turbulence ribs, which enhance convective heat transfer and phase change heat transfer by disrupting the thermal boundary layer and inducing turbulence. The porous wall surface on the cold side promotes liquid phase wetting and microscale phase change, synergistically improving the heat transfer coefficients of both hot and cold sides. The independent layered design of the hot and cold side flow channels supports heterogeneous working fluid combinations such as supercritical CO2-water and liquid hydrogen-liquid oxygen. The multi-stage gradually expanding flow channels, porous wetting surfaces, and turbulence ribs enhance heat transfer and work synergistically with the phase change temperature control layer, achieving improved heat exchange efficiency while reducing pressure drop. It balances compactness, reliability, and wide operating condition adaptability to meet the extreme heat exchange requirements of aerospace, new energy, and other fields. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 An exemplary illustration shows an overall structural diagram of a gradually expanding printed circuit board heat exchange core adapted to two-phase flow, provided in an embodiment of this application.

[0022] Figure 2 An exemplary illustration shows a structural schematic diagram of the cold side plate layer of a gradually expanding printed circuit board type heat exchanger core adapted to two-phase flow, provided in an embodiment of this application.

[0023] Figure 3 An exemplary illustration shows a schematic diagram of the structure of a heat-side plate layer of a gradually expanding printed circuit board type heat exchanger core adapted to two-phase flow, provided in an embodiment of this application.

[0024] Figure 4 An exemplary schematic diagram shows a cover plate or base plate of a gradually expanding printed circuit board heat exchanger core adapted to two-phase flow, provided in an embodiment of this application.

[0025] Figure 5 An exemplary illustration shows a partially enlarged structural diagram of the cold side plate layer of a gradually expanding printed circuit board type heat exchanger core adapted to two-phase flow, provided in an embodiment of this application.

[0026] Figure 6 An exemplary schematic diagram of a partially enlarged thermal side plate layer of a gradually expanding printed circuit board type heat exchanger core adapted to two-phase flow, provided by an embodiment of this application, is shown. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0028] To further illustrate the technical solutions provided in the embodiments of this application, a detailed description is provided below in conjunction with the accompanying drawings and specific implementation methods. Although the embodiments of this application provide method operation steps as shown in the following embodiments or drawings, the method may include more or fewer operation steps based on conventional or non-inventive methods. In steps where there is no logically necessary causal relationship, the execution order of these steps is not limited to the execution order provided in the embodiments of this application.

[0029] refer to Figure 1-6As shown, this application provides a gradually expanding printed circuit board heat exchanger core adapted to two-phase flow, comprising a cover plate 1, a base plate 2, a cold side plate layer 3, and a hot side plate layer 4. The cold side plate layer 3 and the hot side plate layer 4 are respectively located between the cover plate 1 and the base plate 2. The cold side plate layer 3 and the hot side plate layer 4 are alternately stacked in the vertical direction and welded together. Specifically, the cold side plate layer 3 and the hot side plate layer 4 can be connected by diffusion soldering or brazing. The cover plate 1 is welded to adjacent cold side plate layer 3 or hot side plate layer 4, and the base plate 2 is welded to adjacent cold side plate layer 3 or hot side plate layer 4. This application also provides a gradually expanding printed circuit board heat exchanger adapted to two-phase flow, including the gradually expanding printed circuit board heat exchanger core adapted to two-phase flow provided by the above solution.

[0030] Both the cover plate 1 and the base plate 2 include a substrate 11 and a phase change layer 12. The phase change layer 12 is formed inside the substrate 11 or is connected to the substrate 11 by vacuum diffusion welding. The phase change layer 12 is filled with a phase change material. The honeycomb pore size of the phase change layer 12 is 0.5~2mm, the porosity is 60%~80%, and the phase change material used is an aluminum-based paraffin composite material with a filling rate of 90%~95%.

[0031] Therefore, when facing instantaneous high-temperature conditions, such as liquid hydrogen flash evaporation or rapid heat absorption of supercritical CO2, the phase change material can smooth temperature fluctuations by absorbing / releasing latent heat. At the same time, the flexible properties of the phase change layer 12 can alleviate the thermal stress of the metal substrate 11 caused by thermal shock and reduce the thermal fatigue of the heat exchanger.

[0032] The cold side plate layer 3 includes a cold runner inlet 31, a diversion channel 32, a gradually expanding channel 33, and a cold runner outlet 34. The cold runner inlet 31, the diversion channel 32, the gradually expanding channel 33, and the cold runner outlet 34 are all formed on the surface of the cold side plate layer 3. The cold runner inlet 31, the diversion channel 32, the gradually expanding channel 33, and the cold runner outlet 34 are sequentially connected. The medium enters from the cold runner inlet 31 and flows out from the cold runner outlet 34 through the diversion channel 32 and the gradually expanding channel 33. The gradually expanding channel 33 and the diversion channel 32 are arranged in parallel.

[0033] The cross-sectional shape of the flow distribution channel 32, the gradually expanding channel 33, the inlet flow distribution channel 42, the heat exchange channel 43, and the outlet flow distribution channel 44 is one or more of the following: rectangular, semi-circular, circular, elliptical, or polygonal. The flow distribution channel 32, the gradually expanding channel 33, the inlet flow distribution channel 42, the heat exchange channel 43, and the outlet flow distribution channel 44 are straight straight channels, bend channels, or curved channels.

[0034] The diversion channel 32, the gradually expanding channel 33, the inlet diversion channel 42, the heat exchange channel 43, and the outlet diversion channel 44 can be processed by chemical etching, machining, micro-electro-discharge, high-energy laser and other methods.

[0035] The number of expanding channels 33 is greater than the number of diverting channels 32, and the ratio of diverting channels 32 to expanding channels 33 is 1:2, 1:3, or 1:4.

[0036] The width of the gradually widening channel 33 gradually increases along the direction from the cold runner inlet 31 to the cold runner outlet 34.

[0037] The design of the gradually increasing width of the expanding channel 33 along the direction from the cold flow inlet 31 to the outlet is intended to dynamically adapt to the differences in volume changes between the gas and liquid phases in a two-phase flow.

[0038] During two-phase flow, the gaseous working fluid expands significantly due to heat, while the liquid working fluid may contract due to heat transfer or phase change.

[0039] Traditional constant-section flow channels are prone to problems such as sudden increases in local flow resistance, bubble aggregation, or uneven liquid phase distribution due to gas-liquid volume mismatch, which in turn leads to pressure drop fluctuations and decreased heat transfer efficiency. Gradually expanding channels provide physical space buffer for gas phase expansion through the gradual expansion of the channel cross-sectional area, while adapting to the dynamic demand of liquid phase contraction. This allows the gas and liquid phases to naturally adjust their distribution during flow, avoiding flow instability caused by sudden volume changes.

[0040] Furthermore, the gradual expansion structure, through the parallel arrangement of the diversion channel 32 and the gradual expansion channel 33, further guides the medium to be evenly distributed along the flow direction, reduces local velocity differences, and thus creates a stable flow field environment for the coordinated transport and phase change process of the two-phase flow.

[0041] The design of the gradually expanding channel 33 significantly improves the stability and heat transfer uniformity of the two-phase flow. The gradient expansion of the channel width effectively alleviates the squeezing effect of gas phase expansion on the flow cross section, reduces the risk of bubble coalescence and local blockage, and enables the gas and liquid phases to complete volume adjustment at a smoother rate, avoiding turbulent separation or backflow caused by abrupt changes in cross section.

[0042] Meanwhile, the gradually expanding structure gradually reduces the flow resistance per unit cross-section, balances the pressure distribution of the gas and liquid phases along the flow path, suppresses drastic fluctuations in pressure drop, and ensures continuous and stable flow of the medium within the flow channel.

[0043] Furthermore, the synergistic effect of the expanding channel 33 and the diverting channel 32 optimizes the flow distribution, enabling the cold-side medium to uniformly cover the heat exchange surface, reducing "dead zones" or localized overheating / undercooling areas, and enhancing overall heat transfer efficiency. The perforated structure 35 on the inner wall of the flow channel further complements the expanding morphology, promoting the spreading and microscale phase change of the liquid working fluid within the expanding channel through gradient control of surface wettability, thereby strengthening heat transfer at the gas-liquid interface.

[0044] A hole structure 35 is provided on the inner wall of the gradually expanding channel 33. The inner diameter of the hole structure 35 gradually increases along the direction from the cold runner inlet 31 to the cold runner outlet 34.

[0045] The inner wall of the gradually expanding channel 33 is provided with a perforation structure 35 whose inner diameter gradually increases along the flow direction. This aims to optimize the dynamic matching of the gas-liquid phase change process and flow distribution in the two-phase flow through the synergistic effect of gradient surface characteristics and channel morphology. In the two-phase flow, as the medium flows from the cold channel inlet 31 to the outlet, the proportion of the gas phase gradually increases due to heat absorption and expansion, while the liquid phase may contract or undergo local evaporation due to phase change or heat exchange.

[0046] Traditional uniform aperture structures are difficult to adapt to the non-uniform changes in gas-liquid ratio and phase change rate in this flow direction, which can easily lead to problems such as insufficient liquid phase wetting at the inlet or gas phase retention at the outlet.

[0047] By designing the orifice diameter to gradually increase along the flow direction, the smaller orifice structure 35 at the inlet section can maintain a higher capillary pressure, enhance the wettability of the liquid phase in the initial stage, and avoid localized drying of the wall surface caused by rapid expansion of the gas phase; while the orifice diameter at the outlet section gradually increases, thereby reducing capillary resistance, adapting to the flow requirements after the increase in the proportion of gas phase, and promoting the release of gas phase and redistribution of liquid phase.

[0048] Furthermore, the synergistic design of the pore structure 35 and the gradually expanding channel 33 can utilize the velocity reduction effect brought about by the expansion of the flow channel cross-sectional area to extend the residence time of the medium in the pore structure 35 region, thereby enhancing microscale phase change and heat transfer.

[0049] The widening of the gradually expanding channel 33 provides physical expansion space for the gas phase, but simply increasing the cross-sectional area can lead to a decrease in the liquid phase spreading ability (due to reduced flow velocity and enhanced surface tension dominance), potentially causing wetting discontinuity. In this case, the orifice diameter increases synchronously along the flow direction. On the one hand, the small orifice diameter in the inlet section maintains high capillary pressure, forcing the liquid phase to fully wet the wall surface in the early stages of channel expansion; on the other hand, the large orifice diameter in the outlet section reduces capillary constraint, preventing liquid phase stagnation or gas phase blockage caused by excessively wide channels. This allows the gas and liquid phases to both alleviate sudden volume pressure changes using the gradually expanding structure and maintain a dynamic balance between wetting and phase change through the orifice diameter gradient, thereby achieving multi-dimensional optimization from flow field stability to heat transfer efficiency.

[0050] This gradient aperture structure significantly improves the wetting uniformity and phase change heat transfer efficiency of the two-phase flow within the expanding channel 33. The small aperture at the inlet section forces the liquid phase deep into the porous wall through high capillary effect, forming a stable liquid film coverage and suppressing the shading effect of local gas phase accumulation on the heat exchange surface. The large aperture at the outlet section reduces flow resistance, allowing the gas phase to escape efficiently and avoiding discontinuous spreading of the liquid phase due to channel expansion, thus ensuring the dynamic balance of the gas-liquid interface along the flow path.

[0051] Simultaneously, the pore size gradient change and the cross-sectional expansion of the gradually expanding channel 33 create spatial matching: as the channel width increases, the medium velocity decreases, the gas phase expansion space expands, and the gradually increasing pore size adapts to the gas phase volume growth, reducing flow disturbances caused by bubble coalescence and collapse, and maintaining a smooth transition between the gas and liquid phases. Furthermore, the high capillary pressure at the inlet promotes micro-evaporation of the liquid phase, while the low resistance at the outlet supports nucleation boiling of the gas phase, forming a natural transition from forced convection to a phase change-dominated heat transfer mode, thereby achieving efficient and stable heat exchange throughout the entire channel.

[0052] The hot side plate layer 4 includes a hot runner inlet 41, an inlet branch channel 42, a heat exchange channel 43, an outlet branch channel 44, and a hot runner outlet 45. The hot runner inlet 41, the inlet branch channel 42, the heat exchange channel 43, the outlet branch channel 44, and the hot runner outlet 45 are all formed on the surface of the hot side plate layer 4. The hot runner inlet 41, the inlet branch channel 42, the heat exchange channel 43, the outlet branch channel 44, and the hot runner outlet 45 are sequentially connected. The medium enters from the hot runner inlet 41 and flows out from the hot runner outlet 45 after passing through the inlet branch channel 42, the heat exchange channel 43, and the outlet branch channel 44.

[0053] The number of inlet diversion channels 42, heat exchange channels 43 and outlet diversion channels 44 are equal. The inlet diversion channels 42 and heat exchange channels 43 are arranged perpendicularly to each other, and the outlet diversion channels 44 and heat exchange channels 43 are arranged perpendicularly to each other.

[0054] The heat exchange channel 43 is internally provided with baffles 46, and multiple baffles 46 are spaced apart along the extension direction of the heat exchange channel 43. The spacing between adjacent baffles 46 is 2-4 times the width of the heat exchange channel. The width of the baffles 46 gradually increases from the end of the heat exchange channel near the inlet branch channel 42 to the end of the heat exchange channel near the outlet branch channel 44.

[0055] The shape of the baffle 46 is one or more of the following: triangular, trapezoidal, or wavy. The height of the baffle 46 is 20% of the height of the heat exchange channel 43.

[0056] The purpose of the design that the width of the turbulence ribs 46 in the heat exchange channel 43 gradually increases from the inlet to the outlet is as follows: In the initial stage, the liquid phase has a high proportion and a fast flow rate. The flow resistance needs to be reduced by the smaller width of the turbulence ribs 46 to avoid liquid phase backflow or premature gas phase separation caused by sudden disturbance. As the medium flows towards the outlet, heat absorption leads to an increase in the proportion of gas phase and an acceleration of the liquid phase evaporation rate. The viscous resistance of the fluid decreases and the inertial effect is enhanced. At this time, the gradually widening turbulence ribs 46 can enhance the cutting ability of the gas-liquid interface, destroy the thermal boundary layer that has thickened due to the decrease in flow rate, and promote gas phase nucleation boiling and liquid phase micro-convection by enhancing the turbulence intensity.

[0057] In addition, the gradually widening turbulence ribs 46 and the extension direction of the heat exchange channel 43 form an asymmetric flow field structure, which guides the medium to generate a spiral secondary flow in the flow, prolongs the contact time between the gas and liquid phases on the heat exchange surface, and balances the difference in heat load distribution from the inlet to the outlet, avoiding local overheating or the formation of heat transfer dead zones.

[0058] The design of the gradually expanding turbulence ribs 46 significantly improves the heat transfer uniformity and phase change efficiency of the gas and liquid phases within the heat exchange channel 43. The narrower turbulence ribs 46 at the inlet section, while maintaining low flow resistance, moderately disturb the high-velocity liquid phase, disrupting the initial thermal boundary layer and accelerating internal convection of the liquid phase, thus providing preheating conditions for subsequent phase change. The turbulence ribs 46, which gradually widen from the middle section to the outlet section, enhance the blocking effect of the flow channel cross-section, forcing the gas phase to collide violently with the surface of the turbulence ribs 46 during expansion, promoting bubble breakage and redistribution, and inhibiting heat transfer deterioration caused by gas phase coalescence.

[0059] Meanwhile, the gradient expansion of the width of the 46 turbulence ribs dynamically matches the changes in the gas-liquid ratio within the flow channel: when the inlet section is dominated by the liquid phase, the narrow ribs reduce energy loss; after the gas phase ratio increases in the outlet section, the wide ribs enhance the microscale mixing of the gas-liquid interface by expanding the turbulence range, thereby accelerating the evaporation and condensation processes simultaneously.

[0060] In addition, the continuous arrangement of the gradually widening turbulence ribs 46 in the flow channel forms an alternating "sparse-dense" turbulence generation zone, which induces the medium to generate periodic vortices. This not only enhances the heat exchange between the mainstream and the near-wall region, but also balances the temperature field of the flow channel section through the lateral transport effect of the vortices, eliminating the local thermal stress concentration caused by the difference in gas-liquid phase change rate.

[0061] This design enables adaptive control of the entire heat transfer mode from inlet to outlet, allowing forced convection, nucleation boiling and condensation heat transfer to work together efficiently under multi-scale disturbances, thereby improving the overall thermodynamic performance and operating condition adaptability of the heat exchanger.

[0062] The narrow rib structure at the inlet reduces the initial pressure drop and establishes a stable turbulent foundation for the liquid phase through micro-disturbance. As the flow develops, the gradually widening ribs gradually enhance the constraint on the gas phase expansion. By utilizing the interaction between the gas phase inertial force and the surface of the turbulent rib 46, the gas phase expansion energy is converted into turbulent kinetic energy. This not only suppresses the flow channel blockage caused by excessive gas phase accumulation, but also promotes the renewal of the gas-liquid interface through turbulent pulsation.

[0063] Furthermore, the width gradient variation and the shape of the 46 turbulence ribs (triangular / trapezoidal / wavy) form a geometric synergy: the narrow ribs in the inlet section adopt sharp edges (such as triangles) to concentrate the high shear effect and accelerate the stripping of the liquid boundary layer; the wide ribs in the outlet section adopt a gentle transition shape (such as trapezoids) to expand the turbulence coverage area and adapt to the gas phase diffusion requirements.

[0064] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0065] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0066] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0067] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A gradually expanding printed circuit board heat exchange core adapted for two-phase flow, characterized in that, It includes a cover plate, a bottom plate, a cold side plate layer, and a hot side plate layer. The cold side plate layer and the hot side plate layer are respectively located between the cover plate and the bottom plate. The cold side plate layer and the hot side plate layer are alternately stacked in the vertical direction. The cold side plate layer and the hot side plate layer are welded together. Both the cover plate and the bottom plate include a substrate and a phase change layer. The phase change layer is formed inside the substrate and is filled with a phase change material. The cold side plate layer includes a cold runner inlet, a branch channel, a diffuser channel, and a cold runner outlet. The cold runner inlet, the branch channel, the diffuser channel, and the cold runner outlet are all formed on the surface of the cold side plate layer. The cold runner inlet, the branch channel, the diffuser channel, and the cold runner outlet are sequentially connected. The medium enters from the cold runner inlet and flows out from the cold runner outlet via the branch channel and the diffuser channel. The number of diffuser channels is greater than the number of branch channels. The width of the diffuser channel gradually increases along the direction from the cold runner inlet to the cold runner outlet. The hot side plate layer includes a hot runner inlet, an inlet branch channel, a heat exchange channel, an outlet branch channel, and a hot runner outlet. The hot runner inlet, the inlet branch channel, the heat exchange channel, the outlet branch channel, and the hot runner outlet are all formed on the surface of the hot side plate layer. The hot runner inlet, the inlet branch channel, the heat exchange channel, the outlet branch channel, and the hot runner outlet are sequentially connected. The medium enters from the hot runner inlet and flows through the inlet branch channel, the heat exchange channel, and the outlet branch channel before flowing out from the hot runner outlet. The heat exchange channel is provided with flow-tightening ribs inside. The inner wall of the gradually expanding channel is provided with a hole structure, and the inner diameter of the hole structure gradually increases along the direction from the cold runner inlet to the cold runner outlet. The width of the turbulence rib gradually increases from the end of the heat exchange channel near the inlet branch channel to the end of the heat exchange channel near the outlet branch channel.

2. The gradually expanding printed circuit board heat exchange core adapted for two-phase flow according to claim 1, characterized in that, The gradually expanding channel is arranged in parallel with the diversion channel.

3. The gradually expanding printed circuit board heat exchange core adapted for two-phase flow according to claim 2, characterized in that, Multiple turbulence ribs are spaced apart along the extension direction of the heat exchange channel.

4. The gradually expanding printed circuit board heat exchange core adapted for two-phase flow according to claim 3, characterized in that, The number of inlet diversion channels, the number of heat exchange channels, and the number of outlet diversion channels are equal.

5. The gradually expanding printed circuit board heat exchange core adapted for two-phase flow according to claim 1, characterized in that, The height of the turbulence rib is 20% of the height of the heat exchange channel.

6. The gradually expanding printed circuit board heat exchange core adapted for two-phase flow according to claim 5, characterized in that, The inlet diversion channel is perpendicular to the heat exchange channel, and the outlet diversion channel is perpendicular to the heat exchange channel.

7. The gradually expanding printed circuit board heat exchange core adapted for two-phase flow according to claim 6, characterized in that, The ratio of the diversion channel to the expanding channel is 1:2, 1:3, or 1:

4.

8. A gradually expanding printed circuit board heat exchanger adapted for two-phase flow, characterized in that, Includes the gradually expanding printed circuit board heat exchange core adapted for two-phase flow as described in any one of claims 1-7 above.

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