Spray synergistic cooling control method

Abstract

This invention relates to the field of heat dissipation in electronic devices, and particularly to a spray-assisted cooling control method comprising: pre-storing a two-dimensional coordinate system mapping table in a data processor, binding each micro-nozzle and its corresponding micro-motion platform to the coordinates of the covered area, and establishing a mapping relationship between the micro-nozzle number and the physical coordinates; the data processor reading temperature data monitored by a temperature sensor array and liquid film thickness data monitored by a liquid film sensor array in real time, and identifying abnormal areas; querying the two-dimensional coordinate system mapping table to search for the micro-nozzle number covering the coordinates of the identified abnormal area; the data processor activating the corresponding micro-nozzle according to the searched micro-nozzle number and generating control commands to adjust the spray angle and spray parameters of the micro-nozzle. This invention can achieve rapid spatial positioning and precise cooling of dynamic hot spots, solve the problem of collaborative arbitration in overlapping areas of multiple nozzles, dynamically match the cooling medium and heat source intensity, and improve heat dissipation efficiency and system reliability.

Description

Technical Field

[0001] This invention relates to the field of heat dissipation technology for electronic devices, and in particular to a spray-assisted cooling control method. Background Technology

[0002] In fields such as high-performance computing, high-power power electronics, and lasers, as device integration and power density continue to rise, the local heat flux density generated during operation far exceeds the heat dissipation limits of traditional air cooling and single-phase liquid cooling technologies. For example, the local hot spot heat flux density of modern GPU chips can exceed 300 W / cm², posing a severe challenge to heat dissipation technology. Spray cooling technology, due to its advantages such as utilizing the latent heat of phase change of the working fluid, high heat transfer coefficient, low superheat, and small working fluid flow rate, is considered one of the effective ways to solve the above-mentioned high heat flux density heat dissipation problems.

[0003] Existing spray cooling systems typically employ fixed nozzle arrays or single-degree-of-freedom scanning nozzles to cool the heating surface. However, in practical applications, these technical solutions suffer from the following drawbacks: First, heat source distribution is dynamic and non-uniform. During chip operation, the location and heat flux density of hot spots shift in real time with changes in computing load. Fixed nozzles cannot adjust the spray point according to the dynamic changes in hot spot location, resulting in over-cooling in some areas and under-cooling in others. Although single-degree-of-freedom scanning nozzles can reciprocate within a certain range, their response speed is slow and their path planning is rigid, making it difficult to provide precise and rapid "on-demand cooling" for instantaneous small-area micro-hot spots, resulting in wasted cooling fluid and low heat dissipation efficiency.

[0004] Second, there is a lack of refined and coordinated control over the spray coverage area and the liquid film state. When multiple nozzles work together, their coverage areas may overlap. Existing systems lack effective coordinate mapping and area division mechanisms, making it impossible to clearly define the specific physical area each nozzle is responsible for. When a hot spot happens to be located in the overlapping area of ​​two or more nozzles, existing technology cannot intelligently arbitrate based on multi-dimensional factors such as distance, liquid film state, and nozzle lifespan. This can easily lead to nozzle conflicts or mutual shirking of responsibility, resulting in untimely replenishment of liquid in abnormal areas, which in turn can cause local "drying" phenomena, triggering boiling crises or device burnout.

[0005] Third, the control parameter generation logic is simplistic and lacks the ability to match parameters with both spatiotemporal precision. Traditional systems typically employ an open-loop control mode with constant frequency and flow rate, which cannot dynamically adjust the spray pulse frequency and flow rate based on the magnitude of real-time heat flux density. This results in wasted working fluid at low heat flux densities and an inability to meet heat dissipation requirements at high heat flux densities. Furthermore, existing nozzles lack precise pose adjustment capabilities. Even if hotspot shift is detected, they cannot achieve micron-level precision dynamic alignment by driving a two-degree-of-freedom platform with quantified angle control commands. This leads to excessive positional deviation between the spray center and the hotspot, weakening the localized heat dissipation effect of the spray cooling system. Summary of the Invention

[0006] This invention aims to overcome the shortcomings of existing technologies and provide a spray-coordinated cooling control method that can achieve intelligent arbitration, precise positioning, and flow-angle joint regulation of multiple nozzles based on real-time thermal spectrum and liquid film state diagram. This solves the problems of slow response, inaccurate positioning, and low coordination efficiency of existing technologies when dealing with dynamic, non-uniform high heat flux density heat dissipation.

[0007] To achieve the above objectives, the technical solution created by this invention is implemented as follows: A spray-assisted cooling control method is implemented using a spray-assisted cooling control system, which includes a heat dissipation substrate, a temperature sensor array, a liquid film sensor array, a spray unit array, and a data processor; wherein, The first side of the heat dissipation substrate is in contact with the heat source, and the temperature sensor array and liquid film sensor array are evenly distributed on the second side of the heat dissipation substrate. The spray unit array faces the second side of the heat dissipation substrate. Each spray unit includes a micro nozzle, a micro-motion platform, and a micro solenoid valve. The micro nozzle is mounted on the micro-motion platform, which is used to adjust the spray angle of the micro nozzle. The micro solenoid valve is set on the liquid supply line of the micro nozzle and is used to adjust the liquid inlet flow rate of the micro nozzle. The data processor is connected to the temperature sensor array, the liquid film sensor array, the miniature solenoid valve, and the micro-motion platform, respectively. The spray-assisted cooling control method includes the following steps: S1: A two-dimensional coordinate system mapping table is pre-stored in the data processor to bind each micro-nozzle and its corresponding micro-motion platform to the coordinates of the covered area, and to establish a mapping relationship between the micro-nozzle number and the physical coordinates. S2: The data processor reads the temperature data monitored by the temperature sensor array and the liquid film thickness data monitored by the liquid film sensor array in real time, identifies the coordinates of the temperature gradient exceeding the preset temperature gradient threshold or the absolute temperature exceeding the preset absolute temperature warning value as abnormal areas, and identifies the coordinates of the liquid film thickness below the critical maintenance thickness as abnormal areas. S3: Query the two-dimensional coordinate system mapping table to search for the micro-nozzle number that covers the coordinates of the identified abnormal area; S4: The data processor activates the corresponding micro-nozzle based on the searched micro-nozzle number and generates control commands to adjust the spray angle and spray parameters of the micro-nozzle.

[0008] Furthermore, when the identified abnormal area is located in an overlapping area covered by two or more micro-nozzles, the data processor executes the following priority arbitration strategy to determine which micro-nozzle to activate: First, the principle of prioritizing straight-line distance is implemented: the Euclidean distance between the center coordinates of the abnormal area and the projected coordinates of the outlet center of each candidate micro-nozzle on the surface of the heat dissipation substrate is calculated. If the difference between the Euclidean distances corresponding to each candidate micro-nozzle is greater than the preset distance threshold, the micro-nozzle with the smallest Euclidean distance is selected as the micro-nozzle to be started. Secondly, the liquid film state priority principle is implemented: if the distance difference between the Euclidean distances corresponding to each candidate micro-nozzle is less than the preset distance threshold, the data of the liquid film sensor corresponding to each sub-region in the overlapping area is read, and the micro-nozzle corresponding to the thinnest liquid film thickness is selected as the micro-nozzle to be started. If the liquid film thickness is the same in each sub-region of the overlapping area, the load balancing principle is applied: query historical work records and prioritize the micro-nozzle with the shortest cumulative working time or the lowest working frequency as the micro-nozzle to be started.

[0009] Furthermore, the steps for adjusting the spray angle of the micro-nozzle are as follows: The deviation between the center coordinates of the abnormal region and the projection center coordinates of the micro-nozzle on the surface of the heat dissipation substrate is calculated to generate the rotation angle of the micro-motion platform. The rotation angle of the micro-motion platform is converted into a drive signal to drive the micro-motion platform to adjust the spray angle of the micro nozzle.

[0010] Furthermore, let the center coordinates of the anomaly region be ( X h , Y h The projection coordinates of the outlet center of the micro-nozzle on the surface of the heat sink substrate are ( X n0 , Y n0 The vertical height of the micro-nozzle from the surface of the heat sink substrate is H ; Calculate the center coordinates of the anomaly region ( X h , Y h Relative to projected coordinates ( X n0 , Yn0 ) horizontal offset vector Δ X and Δ Y Δ X=X h X n Δ Y=Y h Y n ; Calculate the yaw angle of the micro-motion platform and pitch angle i : ; .

[0011] Furthermore, the spray parameters of the micro-nozzle include pulse frequency and inlet flow rate; The pulse frequency of the micro-nozzle is dynamically adjusted based on the local heat flux density monitored by the temperature sensor array. The theoretical value of the liquid inlet flow rate of the micro nozzle is calculated based on the heat load of the abnormal area, and the opening of the micro solenoid valve is adjusted to keep the liquid inlet flow rate of the micro nozzle within the preset error range of the theoretical value of the liquid inlet flow rate.

[0012] Furthermore, when the local heat flux density detected by the temperature sensor array is lower than the first heat flux density threshold, the pulse frequency of the micro-nozzle is set in the low-frequency range; when the local heat flux density detected by the temperature sensor array is higher than the first heat flux density threshold but lower than the second heat flux density threshold, the pulse frequency of the micro-nozzle is set in the mid-frequency range; and when the local heat flux density detected by the temperature sensor array is higher than the second heat flux density threshold, the pulse frequency of the micro-nozzle is set in the high-frequency range.

[0013] Furthermore, the low-frequency range is 1kHz-5kHz, the mid-frequency range is 5kHz-20kHz, and the high-frequency range is 20kHz-50kHz; the first heat flux density threshold is 100W / cm², and the second heat flux density threshold is 300W / cm².

[0014] Furthermore, the theoretical value of the liquid inlet flow rate of the micro-nozzle is calculated using the following formula. Q : ; in, q This refers to the local heat flux density monitored by the temperature sensor array. A This refers to the coverage area of ​​the micro-nozzle. r The density of the cooling working fluid ejected by the micro-nozzle. L To cool the latent heat of the working fluid, orThis is the heat transfer efficiency factor.

[0015] Furthermore, a preset temperature gradient threshold of 5℃ / cm is set.

[0016] Furthermore, the preset absolute temperature warning value is 85℃.

[0017] Compared with the prior art, the present invention can achieve the following beneficial effects: 1. This invention establishes a two-dimensional coordinate system mapping table to bind the coordinates of each micro-nozzle to its coverage area, thereby enabling rapid positioning of micro-nozzles in abnormal areas and improving the system's response speed.

[0018] 2. This invention effectively solves the coordination problem of multiple micro-nozzles in overlapping areas by designing a multi-level priority arbitration strategy (distance priority, liquid film state priority, and load balancing), avoids micro-nozzle conflicts, ensures timely and reasonable spray cooling in abnormal areas, and extends the overall lifespan of the system.

[0019] 3. The present invention can accurately calculate the required flow rate and pulse frequency according to the heat load of the abnormal area, and realize the dynamic matching of the cooling working fluid and the heat source intensity. The system can reduce energy consumption and working fluid consumption under low heat load, and improve spray density and heat dissipation efficiency under high heat load.

[0020] 4. This invention calculates the rotation angle of the micro-motion platform, enabling the micro-nozzle to be precisely aligned with the abnormal area, ensuring that the cooling medium acts on the center of the abnormal area and improving heat dissipation efficiency. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A schematic diagram of the spray-assisted cooling control method described in an embodiment of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0024] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0025] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] This invention provides a spray-assisted cooling control method, implemented using a spray-assisted cooling control system. Before detailing the spray-assisted cooling control method, the spray-assisted cooling control system will be described in detail first.

[0028] The spray-coordinated cooling control system includes a heat dissipation substrate, a temperature sensor array, a liquid film sensor array, a spray unit array, and a data processor. The first side of the heat dissipation substrate is in contact with the heat source, and the temperature sensor array and the liquid film sensor array are evenly distributed on the second side of the heat dissipation substrate. The spray unit array faces the second side of the heat dissipation substrate and covers different areas of the heat dissipation substrate. It is used to spray atomized cooling medium onto the heat dissipation substrate. The thickness of the cooling medium is the thickness of the liquid film.

[0029] A temperature sensor array is embedded in a grid pattern within a heat sink substrate, near the heat source, to monitor the surface temperature field of the heat source. The temperature sensors employ high-response thin-film thermocouples or resistance temperature detectors.

[0030] A liquid film sensor array is arranged in a grid on the surface of a heat sink substrate to monitor the liquid film thickness. The liquid film sensors employ either optical interferometry or electrical impedance tomography principles.

[0031] The second side of the heat dissipation substrate is divided into different areas, and each spray unit covers one area, meaning that each area is cooled and dissipated by a corresponding spray unit.

[0032] Each spray unit includes a micro nozzle, a micro-motion platform, and a micro solenoid valve. The micro nozzle is mounted on the micro-motion platform, which is used to adjust the spray angle of the micro nozzle. The micro solenoid valve is located on the liquid supply line of the micro nozzle and is used to adjust the liquid inlet flow rate of the micro nozzle.

[0033] The heat dissipation substrate and the micro-motion platform can be integrated into a heat dissipation box. A through hole is provided in the bottom of the heat dissipation box. The heat dissipation substrate is fixed on the bottom of the heat dissipation box, and one surface of the heat dissipation substrate is exposed to the heat dissipation box and in contact with the heat source. The top surface of the micro-motion platform is fixed to the top of the heat dissipation box. The micro nozzle is installed on the bottom surface of the micro-motion platform. The micro nozzle is used to spray cooling working fluid onto the heat dissipation substrate below.

[0034] The micro-nozzles are high-density micro-nozzles manufactured using microelectromechanical systems (MEMS) technology. The spraying action of each micro-nozzle can be independently controlled. The micro-nozzles can be piezoelectric, electrostatic, or thermal bubble type to achieve precise spraying at low flow rates and high frequencies. The micro-motion platform uses a micro two-dimensional piezoelectric ceramic drive platform or a voice coil motor platform.

[0035] The data processor is connected to the temperature sensor array, the liquid film sensor array, the miniature solenoid valve, and the micro-motion platform. The data processor receives monitoring data from the temperature sensor array and the liquid film sensor array, identifies abnormal areas, and generates spray control commands and micro-motion platform control commands. The spray control commands control the spray adjustment components to adjust the spray parameters (including flow rate and frequency) of the miniature nozzles, while the micro-motion platform control commands control the position and orientation of the micro-motion platform to adjust the spray angle of the miniature nozzles.

[0036] The spray-assisted cooling control method provided in this invention includes the following steps: S1: A two-dimensional coordinate system mapping table is pre-stored in the data processor to bind each micro-nozzle and its corresponding micro-motion platform to the coordinates of the covered area, thus establishing a mapping relationship between the micro-nozzle number and the physical coordinates.

[0037] A two-dimensional Cartesian coordinate system is established with the geometric center of the heat sink substrate as the origin (0,0). Each micro-nozzle and its corresponding micro-motion platform have a unique identification number and a fixed coverage area coordinate range in this coordinate system. X n, Y n The coordinate range of the coverage area is determined comprehensively based on the spray diffusion angle of the micro-nozzle, the installation height, and the maximum adjustment range of the micro-motion platform. For example, for the micro-nozzle numbered No.1, its coverage area coordinate range can be set as ( X 1_min , X 1_max , Y 1_min , Y 1_max Within this area, the heat dissipation needs are, in principle, met by the micro-nozzle. Through this two-dimensional coordinate system mapping table, the system establishes a mapping relationship between the micro-nozzle number and its physical coordinates, providing a spatial index basis for subsequent area identification and nozzle locking.

[0038] This invention establishes a two-dimensional coordinate system mapping table to bind the coordinates of each micro-nozzle to the coordinates of its coverage area, thereby enabling rapid positioning of micro-nozzles in abnormal areas and improving the system's response speed.

[0039] S2: The data processor reads the temperature data monitored by the temperature sensor array in real time and identifies the coordinates of the temperature gradient exceeding the preset temperature gradient threshold or the absolute temperature exceeding the preset absolute temperature warning value as abnormal areas.

[0040] The data processor reads temperature data from the temperature sensors in real time and calculates the absolute temperature T of each temperature sensor. abs And the temperature gradient ΔT (unit: °C / cm) of the temperature sensors in the four adjacent directions. When the absolute temperature T of the temperature sensor... abs When the temperature exceeds a preset absolute temperature warning value (e.g., 85℃), the coordinates of the temperature sensor are identified as a hotspot region. Alternatively, when the temperature gradient between the temperature sensor and its adjacent temperature sensors exceeds a preset temperature gradient threshold (e.g., 5℃ / cm), the coordinates of the temperature sensor are identified as a hotspot region. The preset temperature gradient threshold and preset absolute temperature warning value can be dynamically adjusted according to the thermal design power (TDP) of the heat source.

[0041] Simultaneously, the data processor reads the liquid film thickness data from the liquid film sensors in real time. When the liquid film thickness detected by a certain liquid film sensor is lower than the critical maintenance thickness (e.g., 0.1 mm), the coordinates of the liquid film sensor are identified as a weak area of ​​the liquid film. The critical maintenance thickness is set comprehensively based on the physical properties of the cooling medium (such as surface tension and evaporation rate) and the working environment of the heat dissipation substrate to ensure that the liquid film below this thickness is free from the risk of drying out or phase change failure.

[0042] It should be noted that both hotspot areas and thin liquid film areas are anomalous regions. These two types of anomalous regions may appear at the same coordinate location or at different coordinate locations. The data processor marks and prioritizes the two types of anomalous regions separately. Typically, temperature anomalies are used as the first-level response trigger condition, and liquid film anomalies are used as the second-level response trigger condition. However, both can independently trigger the subsequent micro-nozzle locking process.

[0043] S3: Query the two-dimensional coordinate system mapping table to search for the micro-nozzle number that covers the coordinates of the identified abnormal area.

[0044] Based on the two-dimensional coordinate system mapping table from step S1, the data processor retrieves all micro-nozzle numbers covering both types of anomaly regions. Specifically, the data processor assigns the center coordinates of the anomaly regions (…). X h , Y h ) and the coordinate range of the coverage area of ​​each micro-nozzle ( X n , Y n Compare and filter out those whose coverage area includes the coordinates ( X h , Y h All candidate micro-nozzles.

[0045] When the identified abnormal area is only within the coverage of a single micro-nozzle, the data processor directly locks that micro-nozzle as the activated nozzle.

[0046] When the identified abnormal area is located in the overlapping area of ​​two or more micro-nozzle coverage areas, the data processor executes the following priority arbitration strategy to determine the nozzle that is ultimately activated: Level 1: Distance priority principle.

[0047] Calculate the center coordinates of the anomaly region ( X h , Y h The projection coordinates of the outlet centers of each candidate micro-nozzle onto the surface of the heat sink substrate. X n0 , Y n0 Euclidean distance between ) If the distance difference between the Euclidean distances corresponding to each candidate micro-nozzle is greater than the preset distance threshold, then the micro-nozzle with the smallest Euclidean distance is selected as the micro-nozzle to be started.

[0048] For example, the Euclidean distance between the center coordinates (5,15) of the abnormal region and the projected coordinates (3,14) of the micro-nozzle a.D a =2.236mm, the Euclidean distance between the center coordinates (5,15) of the abnormal area and the projected coordinates (0,10) of the micro-nozzle b. D b =7.07mm. Then eliminate micro nozzle b and activate micro nozzle a.

[0049] Level 2: Priority principle for liquid film state.

[0050] If the distance difference between the Euclidean distances corresponding to each candidate micro-nozzle is less than a preset distance threshold (e.g., 0.5 mm), the data of the liquid film sensor corresponding to each sub-region within the overlapping area is read, and the micro-nozzle corresponding to the thinnest liquid film thickness is selected as the micro-nozzle to be started, so as to prevent phase change failure in this region due to untimely liquid replenishment.

[0051] Assuming the liquid film thickness in the area corresponding to micro-nozzle a is 0.12 mm (slightly above the critical value), and the liquid film thickness in the area corresponding to micro-nozzle b is 0.08 mm (below the critical value), the system will preferentially select micro-nozzle b because its covered area has a higher risk of drying out and requires immediate liquid replenishment.

[0052] Level 3: Load balancing principle.

[0053] If the liquid film thickness is the same in each sub-region of the overlapping area, the load balancing principle is implemented: query historical work records and prioritize the micro-nozzle with the shortest cumulative working time or the lowest working frequency as the micro-nozzle to start, so as to avoid fatigue damage caused by frequent operation of a single micro-nozzle, thereby extending the overall life of the system.

[0054] If the system determines that the maximum coverage radius (8mm) of a single micro-nozzle is insufficient to cover the entire hot spot area (e.g., the hot spot area has a diameter of 20mm), or if the local heat flux density detected by the temperature sensor exceeds 400W / cm² and the flow rate of a single micro-nozzle reaches its upper limit but still cannot suppress the temperature rise, then two adjacent micro-nozzles are activated simultaneously, and their respective compensation angles are calculated (see step S4) to achieve dual-nozzle coordinated spraying. The spray cones of the two micro-nozzles can overlap to cover the hot spot, forming a superimposed cooling effect.

[0055] This invention effectively solves the coordination problem of multiple micro-nozzles in overlapping areas by designing a multi-level priority arbitration strategy (distance priority, liquid film state priority, and load balancing), avoids micro-nozzle conflicts, ensures timely and reasonable spray cooling in abnormal areas, and extends the overall lifespan of the system.

[0056] S4: The data processor activates the corresponding micro-nozzle based on the searched micro-nozzle number and generates control commands to adjust the spray angle and spray parameters of the micro-nozzle.

[0057] The spray parameters of the micro-nozzle include pulse frequency and inlet flow rate. The pulse frequency of the micro-nozzle is dynamically adjusted based on the local heat flux density monitored by the temperature sensor array. The theoretical value of the inlet flow rate of the micro-nozzle is calculated based on the heat load of the abnormal area, and the opening of the micro-solenoid valve is adjusted to maintain the inlet flow rate of the micro-nozzle within a preset error range (e.g., ±5%) of the theoretical value of the inlet flow rate.

[0058] The pulse frequency is not a fixed value, but depends on the monitored local heat flux density. q And make dynamic adjustments. Specifically, when the monitored local heat flux density q When the pulse frequency is below 100W / cm², the data processor sets the pulse frequency in the low-frequency range, such as 1kHz to 5kHz; when q When the pulse frequency is between 100W / cm² and 300W / cm², the data processor sets the pulse frequency in the intermediate frequency range, for example, 5kHz to 20kHz; when q Under extreme operating conditions exceeding 300 W / cm², the data processor sets the pulse frequency in the high-frequency range, such as 20 kHz to 50 kHz. By dynamically adjusting the pulse frequency, the system can reduce energy consumption and working fluid consumption under low heat loads, and increase spray density and heat dissipation efficiency under high heat loads.

[0059] Theoretical value of liquid inlet flow rate of micro nozzle Q The calculation formula is: ; in, q This refers to the local heat flux density monitored by the temperature sensor array. A This refers to the coverage area of ​​the micro-nozzle. r The density of the cooling working fluid ejected by the micro-nozzle. L To cool the latent heat of the working fluid, or This is the heat transfer efficiency factor.

[0060] This invention can accurately calculate the required flow rate and pulse frequency based on the heat load of abnormal areas, and achieve dynamic matching between the cooling working fluid and the heat source intensity. The system can reduce energy consumption and working fluid consumption under low heat load, and improve spray density and heat dissipation efficiency under high heat load.

[0061] The steps for adjusting the spray angle of the micro-nozzle are as follows: First, the deviation between the center coordinates of the abnormal area and the projection center coordinates of the micro-nozzle on the surface of the heat sink is calculated to generate the rotation angle of the micro-motion platform.

[0062] Let the center coordinates of the abnormal region be ( X h , Y hThe projection coordinates of the outlet center of the micro-nozzle on the surface of the heat sink substrate are ( X n0 , Y n0 The vertical height of the micro-nozzle from the surface of the heat sink substrate is H ; Calculate the center coordinates of the anomaly region ( X h , Y h Relative to projected coordinates ( X n0 , Y n0 ) horizontal offset vector Δ X and Δ Y Δ X=X h X n Δ Y=Y h Y n ; Calculate the yaw angle of the micro-motion platform and pitch angle : ; .

[0063] Then, the rotation angle of the micro-motion platform is converted into a drive signal to drive the micro-motion platform to adjust the spray angle of the micro nozzle.

[0064] The data processor will calculate ( , The signal is converted into a driving voltage signal for a micro two-dimensional piezoelectric ceramic driving platform or a voice coil motor platform, driving the nozzle to align with the abnormal area. The system has a preset angular resolution of 0.01°, ensuring that the deviation between the spray center and the hot spot center is controlled within the micrometer range.

[0065] This invention calculates the rotation angle of the micro-motion platform, enabling the micro-nozzle to be precisely aligned with the abnormal area, ensuring that the cooling medium acts on the center of the abnormal area and improving heat dissipation efficiency.

[0066] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0067] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A spray collaborative cooling control method is realized by using a spray collaborative cooling control system. The spray collaborative cooling control system includes a heat dissipation substrate, a temperature sensor array, a liquid film sensor array, a spray unit array, and a data processor. Among them, The first surface of the heat dissipation substrate is in contact with the heat source, and the temperature sensor array and the liquid film sensor array are evenly distributed on the second surface of the heat dissipation substrate. The spray unit array faces the second surface of the heat dissipation substrate. Each spray unit includes a micro nozzle, a micro motion platform, and a micro solenoid valve. The micro nozzle is installed on the micro motion platform, and the micro motion platform is used to adjust the spraying angle of the micro nozzle. The micro solenoid valve is arranged on the liquid supply pipeline of the micro nozzle and is used to adjust the liquid inlet flow rate of the micro nozzle. The data processor is respectively connected to the temperature sensor array, the liquid film sensor array, the micro solenoid valve, and the micro motion platform. It is characterized in that the spray collaborative cooling control method includes the following steps: S1: Pre-store a two-dimensional coordinate system mapping table in the data processor, bind each micro nozzle and its corresponding micro motion platform to the coordinates of the covered area, and establish a mapping relationship between the micro nozzle number and the physical coordinates. S2: The data processor reads the temperature data monitored by the temperature sensor array and the liquid film thickness data monitored by the liquid film sensor array in real time, identifies the coordinate points where the temperature gradient exceeds the preset temperature gradient threshold or the absolute temperature exceeds the preset absolute temperature warning value as abnormal areas, and identifies the coordinate points where the liquid film thickness is lower than the critical maintenance thickness as abnormal areas. S3: Query the two-dimensional coordinate system mapping table and search for the micro nozzle numbers covering the coordinates of the identified abnormal areas. S4: The data processor starts the corresponding micro nozzle according to the searched micro nozzle number and generates a control instruction to adjust the spraying angle and spraying parameters of the micro nozzle.

2. The spray-assisted cooling control method according to claim 1, characterized in that, When the identified abnormal area is located in the overlapping area covered by two or more micro nozzles, the data processor executes the following priority arbitration strategy to determine the started micro nozzle: First, execute the principle of straight-line distance priority: Calculate the Euclidean distance between the center coordinates of the abnormal area and the projected coordinates of the outlet centers of each candidate micro nozzle on the surface of the heat dissipation substrate. If the distance difference between the Euclidean distances corresponding to each candidate micro nozzle is greater than the preset distance threshold, select the micro nozzle with the smallest Euclidean distance as the started micro nozzle. Secondly, execute the principle of liquid film state priority: If the distance difference between the Euclidean distances corresponding to each candidate micro nozzle is less than the preset distance threshold, read the data of the liquid film sensors corresponding to each sub-region in the overlapping area, and select the micro nozzle corresponding to the thinnest liquid film thickness as the started micro nozzle. If the liquid film thickness of each sub-region in the overlapping area is the same, execute the load balancing principle: Query the historical work records and preferentially select the micro nozzle with the shortest cumulative working time or the lowest working frequency as the started micro nozzle.

3. The spray-assisted cooling control method according to claim 1, characterized in that, The steps to adjust the spraying angle of the micro nozzle are as follows: Calculate the deviation between the center coordinates of the abnormal area and the projected center coordinates of the micro nozzle on the surface of the heat dissipation substrate, and generate the rotation angle of the micro motion platform. Convert the rotation angle of the micro motion platform into a driving signal to drive the micro motion platform to adjust the spraying angle of the micro nozzle.

4. The spray-assisted cooling control method according to claim 3, characterized in that, a... The center coordinates of the abnormal region are ( X h , Y h The projection coordinates of the outlet center of the micro-nozzle on the surface of the heat sink substrate are ( X n0 , Y n0 The vertical height of the micro-nozzle from the surface of the heat sink substrate is H ; Calculate the center coordinates of the anomaly region ( X h , Y h Relative to projected coordinates ( X n0 , Y n0 ) horizontal offset vector Δ X and Δ Y Δ X = X h X n Δ Y=Y h Y n ; Calculate the yaw angle of the micro-motion platform and pitch angle θ : ； 。 5. The spray-assisted cooling control method according to claim 1, characterized in that, The spray parameters of a micro-nozzle include pulse frequency and inlet flow rate; The pulse frequency of the micro-nozzle is dynamically adjusted based on the local heat flux density monitored by the temperature sensor array. The theoretical value of the liquid inlet flow rate of the micro nozzle is calculated based on the heat load of the abnormal area, and the opening of the micro solenoid valve is adjusted to keep the liquid inlet flow rate of the micro nozzle within the preset error range of the theoretical value of the liquid inlet flow rate.

6. The spray-assisted cooling control method according to claim 5, characterized in that, When the local heat flux density detected by the temperature sensor array is lower than the first heat flux density threshold, the pulse frequency of the micro-nozzle is set in the low-frequency range; when the local heat flux density detected by the temperature sensor array is higher than the first heat flux density threshold but lower than the second heat flux density threshold, the pulse frequency of the micro-nozzle is set in the mid-frequency range; when the local heat flux density detected by the temperature sensor array is higher than the second heat flux density threshold, the pulse frequency of the micro-nozzle is set in the high-frequency range.

7. The spray-assisted cooling control method according to claim 6, characterized in that, The low-frequency range is 1kHz-5kHz, the mid-frequency range is 5kHz-20kHz, and the high-frequency range is 20kHz-50kHz; the first heat flux density threshold is 100W / cm², and the second heat flux density threshold is 300W / cm².

8. The spray-assisted cooling control method according to claim 5, characterized in that, The theoretical value of the liquid inlet flow rate of the micro-nozzle is calculated using the following formula. Q : ； in, q This refers to the local heat flux density monitored by the temperature sensor array. A This refers to the coverage area of ​​the micro-nozzle. ρ The density of the cooling working fluid ejected by the micro-nozzle. L To cool the latent heat of the working fluid, η This is the heat transfer efficiency factor.

9. The spray-assisted cooling control method according to claim 1, characterized in that, The preset temperature gradient threshold is 5℃ / cm.

10. The spray-assisted cooling control method according to claim 1, characterized in that, The preset absolute temperature warning value is 85℃.

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