A double-port micro-channel liquid cooling component micro-leakage diagnosis system and method

Abstract

This invention discloses a microleakage diagnosis system and method for a dual-port microchannel liquid cooling assembly, belonging to the field of microchannel fault diagnosis technology. The system includes a dual-port microchannel liquid cooling assembly, an external circulation condition adjustment module, a multi-parameter sensing module, a two-stage capillary exposure module, and a data processing and control module. This invention employs a complete process of steady-state setup – balanced baseline construction – temperature-pressure coupling active excitation – multi-dimensional fault discrimination. A primary capillary collection channel, a transition flow-limiting section, and a secondary exposure cavity are set around the leakage-sensitive interface to achieve directional collection, temporal separation, and step-by-step exposure of trace leaked liquid. Combining parameters such as inlet and outlet temperature rise, near-far thermal response difference, and wetting signal triggering timing and hysteresis tail characteristics, it accurately distinguishes early microleakage, direct external leakage, flow imbalance, blockage, and air entrapment anomalies. This invention can effectively identify concealed microleakage, reduce the false leak detection rate, and improve the operational reliability of the liquid cooling system.

Description

Technical Field

[0001] This invention belongs to the field of microchannel fault diagnosis technology, specifically relating to a microleakage diagnosis system and method for a dual-port microchannel liquid cooling assembly. Background Technology

[0002] As semiconductor devices, power devices, and highly integrated electronic components evolve towards higher power density, miniaturization, and higher reliability, the heat flux density during device operation continues to increase. Traditional heat dissipation methods such as air cooling and heat pipes are no longer sufficient to meet the heat dissipation requirements in high heat flux density scenarios. Microchannel liquid cooling technology, due to its advantages such as high heat exchange efficiency, compact structure, strong temperature control capability, and ease of integration, has been widely used in the thermal management systems of various high heat flux density devices. Among them, single-inlet, single-outlet, dual-port microchannel liquid cooling integrated components have become the most common type of liquid cooling component in engineering applications due to their fewer external interfaces, compact structure, and convenient system adaptation. This type of component typically has only one inlet and one outlet. After the coolant enters through the inlet, it flows into the microchannel heat exchange zone through the inlet distribution area, and after completing heat exchange, it is discharged through the outlet confluence area.

[0003] During the long-term operation of the aforementioned dual-port microfluidic liquid-cooled integrated components, leakage is a key risk factor affecting their operational reliability and safety. Once coolant leaks, it not only weakens heat exchange capacity and causes temperature runaway in the device, but may also further lead to secondary problems such as decreased electrical insulation, localized corrosion, interface delamination, and the expansion of seal failure. Existing leak detection methods mainly include offline detection and online monitoring. Offline detection typically employs pressure holding tests, airtightness tests, or other pre-shipment leak detection methods. These methods can detect continuous leaks under static operating conditions, but are difficult to detect intermittent micro-leakage that only occurs under actual operating conditions. Online monitoring monitors macroscopic parameters such as the total pressure drop, total flow rate, and inlet / outlet temperature rise of the component, or uses external leak sensors to trigger alarms.

[0004] However, in dual-port microchannel liquid-cooled integrated components, some leaks do not manifest as continuous, continuous, direct external leakage, but rather as a more concealed form of micro-leakage. Specifically, in dual-port microchannel liquid-cooled integrated components, bonding boundaries, sealing interfaces, interlayer bonding surfaces, or other local connection areas may develop tiny gaps due to manufacturing deviations, stress concentration caused by thermal cycling, and mismatches in the thermal expansion coefficients of different materials. These tiny gaps are usually closed or nearly closed under static or conventional steady-state conditions, only opening briefly under specific temperature, pressure, and thermal expansion stress coupling effects, resulting in a small amount of coolant seepage. When the corresponding conditions are removed, the tiny gap closes again, and the leakage stops. Because this type of leakage is significantly condition-dependent, discontinuous, and short-lived, existing detection methods based on conventional steady-state parameters are difficult to detect in a timely manner. Furthermore, this type of micro-leakage usually does not immediately form externally visible leakage fluid in its early stages. Small leaks of coolant often migrate, stagnate, and accumulate along bond boundaries, interlayer gaps, sealing interface edges, or capillary gaps on material surfaces. Therefore, in the early stages of leakage, liquid leakage and reliability risks already exist inside the component or near the interface, but the coolant has not yet flowed to the outer surface of the component or contacted the external leak sensor. Consequently, the external sensor cannot trigger an alarm in a timely manner. Only when the leakage further expands, the accumulated liquid breaks through interface constraints, and leaks to the sensor's location can existing external monitoring methods identify the fault. This results in a significant lag in early risk identification in current technologies.

[0005] Furthermore, existing online monitoring generally relies on macroscopic parameters such as total pressure drop, total flow rate, and temperature rise at the inlet and outlet sides of the components. However, the dual-port structure itself means that these parameters reflect the overall system state and cannot directly characterize the actual changes in local interfaces or flow channels within the components. Especially in actual operation, various faults such as local blockage, system air entrainment, uneven flow distribution, and local micro-leakage can all cause abnormal changes in total pressure drop, total flow rate, or temperature rise, making different types of faults exhibit mutually coupled and difficult-to-distinguish characteristics at the macroscopic parameter level. In other words, existing technologies not only struggle to detect these micro-leakage phenomena in a timely manner, but even when anomalies are detected in the later stages of micro-leakage, the leakage characteristics are easily confused with ordinary flow anomalies, leading to missed or false diagnoses. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: Firstly, a microleakage diagnostic system for a dual-channel microfluidic assembly is proposed, comprising: The dual-port microfluidic liquid cooling assembly includes, in sequence along the fluid flow direction, a connected liquid inlet, an inlet distribution chamber, a microfluidic heat exchange zone, an outlet manifold, and a liquid outlet; one side of the microfluidic heat exchange zone includes a cooling heat source mounting area. The external circulation condition adjustment module is used to provide circulating coolant to the dual-port microchannel liquid cooling component, and to regulate the flow rate, static pressure and temperature of the circulating coolant entering the dual-port microchannel liquid cooling component; the external circulation condition adjustment module forms a closed circulation loop with the dual-port microchannel liquid cooling component through the fluid pipeline; A multi-parameter sensing module is used to collect fluid parameters of the closed loop, temperature parameters of the dual-port microchannel liquid cooling component, and wetting signals of the leakage liquid in real time. A two-stage capillary exposure module is positioned around the leakage-sensitive interface. The leakage-sensitive interface includes the structural interface where micro-gaps and micro-leakage occur during the processing, packaging, and operation of the dual-port microfluidic liquid cooling assembly. Along the direction of leakage fluid migration, the two-stage capillary exposure module sequentially includes a primary capillary collection channel, a transition flow-limiting section, and a secondary exposure cavity located near the outer edge of the leakage-sensitive interface. The flow cross-sectional area of ​​the transition flow-limiting section is smaller than the flow cross-sectional area of ​​the primary capillary collection channel and the flow cross-sectional area of ​​the secondary exposure cavity. A primary wetting sensor is installed in the primary capillary collection channel, and a secondary wetting sensor is installed in the secondary exposure cavity. The data processing and control module is used to realize operating condition control, data acquisition and processing, equalization baseline establishment, and fault identification and classification; the data processing and control module communicates with the multi-parameter sensing module and the external circulation operating condition adjustment module.

[0007] Secondly, a method for diagnosing microleakage in a dual-channel microfluidic assembly is proposed. Based on the dual-channel microfluidic assembly microleakage diagnosis system described in the first aspect, the following steps are performed: Multiple candidate operating points were set within the rated operating range of the dual-port microchannel liquid cooling assembly. The total flow rate, system pressure drop, near-end region outer wall temperature, far-end region outer wall temperature, and wetting status of the two-stage wetting sensors were collected for each candidate operating point. The near-end and far-end thermal response difference was calculated based on the near-end and far-end outer wall temperatures. The candidate operating points were sorted from small to large according to the near-end and far-end thermal response difference. Combining the total flow rate, system pressure drop, and wetting status of the two-stage wetting sensors, the balanced baseline operating point was selected from the sorted candidate operating points. Under the operating conditions corresponding to the equilibrium baseline operating point, the steady-state total flow, steady-state system pressure drop, and steady-state near-far thermal response difference are collected to establish the equilibrium baseline envelope. At the balanced baseline operating point, controlled pressure loading, controlled thermal loading, and controlled recovery are executed sequentially, and the total flow rate, system pressure drop, near-far thermal response difference, and wetting status of the two wetting sensors are collected in real time. When neither of the two wetting sensors outputs a wetting signal, the total flow rate, system pressure drop, and near-far thermal response difference collected in real time are compared with the equalization baseline envelope. When at least one of them exceeds the normal range of the corresponding baseline in the equalization baseline envelope, a non-leakage anomaly is determined. When the two-stage wetting sensors output wetting signals, the triggering sequence, triggering time interval, and wetting signal continuity status after the system recovers to the equilibrium baseline operating point are extracted. If the first-stage wetting sensor outputs a wetting signal before the second-stage wetting sensor, there is a triggering time interval between them, and the two-stage wetting sensors continue to output wetting signals after the system recovers to the equilibrium baseline operating point, it is determined that there is micro-leakage in the dual-port microfluidic liquid cooling component.

[0008] Compared with existing technologies, this invention has the following advantages and beneficial effects: Through a complete diagnostic process of steady-state setup, benchmark construction, operating condition excitation, and fault identification, combined with a two-stage capillary exposure structure and multi-parameter collaborative identification, it can accurately identify early, hidden, and operating condition-dependent microleakage caused by local micro-gap within the rated safe operating conditions of dual-port microchannel liquid cooling components. This fundamentally solves the problems of existing technologies, such as difficulty in capturing micro-leakage, easy confusion between leakage and flow imbalance / blockage / air entrapment, delayed fault identification, and high rate of false positives and false negatives. The system first establishes a balanced baseline envelope adapted to the individual differences of the tested components, eliminating diagnostic interference caused by processing and assembly deviations. Then, through active excitation via temperature and pressure coupling, it causes hidden micro-gap to open briefly, forcibly making discontinuous micro-leakage explicit. Simultaneously, using a step-by-step capture and time-sequential separation structure of a primary capillary collection channel, a transition flow restriction section, and a secondary exposure cavity, it distinguishes the collection and exposure processes of the leaking liquid in time, forming the typical characteristics of the primary wetting signal being triggered first, the secondary wetting signal being triggered later, and the wetting signal still lags and trailing after the operating condition is restored. Finally, by combining the fluctuation patterns of pressure drop, flow rate, inlet and outlet temperature rise, and near-far thermal response difference with the timing and hysteresis characteristics of the wetting signal, it achieves clear classification and discrimination of normal state, flow imbalance / blockage, system air entrapment, direct external leakage, and early micro-leakage. Without disassembling the components or affecting normal operation, it significantly improves the timeliness, sensitivity, and accuracy of micro-leakage detection, ensuring the long-term reliability and safety of the dual-port microchannel liquid cooling components. Attached Figure Description

[0009] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings: Figure 1 This is a block diagram of a microleakage diagnostic system for a dual-port microfluidic liquid cooling assembly provided in Embodiment 1 of the present invention. Detailed Implementation

[0010] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The illustrative embodiments and descriptions of this invention are for illustrative purposes only and are not intended to limit the invention. The embodiments described below are some, but not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0011] In the following description, numerous specific details are set forth to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other embodiments, well-known structures, materials, or methods are not specifically described to avoid obscuring the invention. Unless otherwise specified, the materials, instruments, and reagents used in the following embodiments are commercially available. Unless otherwise specified, the techniques used in the embodiments are conventional methods well known to those skilled in the art.

[0012] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0013] Example 1: Addressing the difficulty of timely detection of early microleakage caused by localized micro-gaps in dual-port microchannel liquid-cooled integrated components using existing technologies, and the tendency to confuse leakage characteristics with ordinary flow anomalies even when anomalies are detected later, leading to missed or incorrect diagnoses, this example provides a microleakage diagnostic system for dual-port microchannel liquid-cooled components. This system executes a complete technical route of "steady-state setup - baseline construction - operating condition excitation - fault identification," enabling timely and accurate identification of microleakage faults in dual-port microchannel liquid-cooled integrated components. The complete technical approach specifically refers to the following: First, within the rated operating range of the tested dual-port microchannel liquid-cooled integrated component, the operating point with the most balanced flow distribution and the most stable temperature distribution is identified. Then, a balanced baseline envelope is established as the standard reference for subsequent flow balancing and leak diagnosis. Based on the balanced baseline, a temperature-pressure coupling operating window is constructed through controlled pressure loading and controlled heat loading to actively trigger microleakage. Simultaneously, two-stage capillary exposure structures are set around the leak-sensitive interface where micro-gap and microleakage may occur, allowing for directional collection, flow restriction, retention, and step-by-step exposure of the microleakage fluid that was originally near the leak-sensitive interface. Finally, by combining the triggering sequence of the wetting signal, the hysteresis characteristics of the recovery phase, and the changing patterns of pressure drop, total flow rate, and near-far thermal response difference, different leakage types are distinguished. It should be noted that the leak-sensitive interface refers to the structural interface where micro-gap and microleakage occur during the processing, packaging, and long-term operation of the dual-port microchannel liquid-cooled component. The interface of this structure includes, but is not limited to, the bonding boundary between the capping layer and the substrate layer, the welding boundary, the bonding interface between multilayer laminated structures, the connection and sealing interface between the fluid port and the component housing, and the sealing boundary of the sealing ring around the microchannel. It also includes the material bonding interface around the fluid through-hole structure, the through-hole structure, and the transition structure.

[0014] Based on the above complete technical approach, the dual-port microchannel liquid cooling component microleakage diagnostic system includes: Figure 1 The dual-port microfluidic liquid cooling assembly, external circulation condition adjustment module, multi-parameter sensing module, two-stage capillary exposure module, and data processing and control module shown are interconnected and interact with each other through fluid pipelines and electrical circuits, working together to complete the entire microleakage diagnosis process.

[0015] 1. Dual-port microchannel liquid cooling assembly The dual-port microfluidic liquid cooling assembly is the test object of this system, employing a single-inlet, single-outlet dual-port structure. Internally, the microchannels of the dual-port microfluidic liquid cooling assembly, along the flow direction of the coolant, sequentially include an interconnected inlet, an inlet distribution chamber, a microchannel heat exchange zone, an outlet manifold, and an outlet. One side of the microchannel heat exchange zone is the mounting area for the heat source to be cooled, used to attach and mount heat-generating components such as chips and power devices to be cooled. The other side and periphery of the microchannel heat exchange zone constitute the encapsulation structure.

[0016] 2. External circulation operating condition adjustment module The external circulation condition regulation module provides circulating coolant to the dual-port microfluidic liquid cooling assembly, and simultaneously regulates the flow rate, static pressure, and temperature of the circulating coolant entering the assembly, providing controllable operating conditions for establishing an equilibrium baseline and excitation temperature and pressure window. The external circulation condition regulation module forms a closed coolant circulation loop with the dual-port microfluidic liquid cooling assembly via fluid piping. Along the coolant flow direction, this closed coolant circulation loop sequentially includes: a storage tank, a circulation pump, a liquid temperature regulation unit, a filter, the dual-port microfluidic liquid cooling assembly, and a back pressure regulating valve. Additionally, a bypass vent branch is connected in parallel between the output of the circulation pump and the storage tank, and an vent control valve is installed on the bypass vent branch.

[0017] (1) Storage tank The coolant reservoir is used to store circulating coolant, vent air, stabilize pressure, and perform temperature buffering. It is equipped with a level sensor to monitor the coolant level and a temperature sensor to monitor the coolant base temperature. A vent is located on the top of the reservoir to expel air from the entire system.

[0018] (2) Circulating pump The circulating pump powers the coolant circulation. The circulating pump must meet the following requirement: within the rated flow range of the dual-port microchannel liquid cooling assembly (or the flow adjustment range involved in the diagnostic process), the absolute relative deviation between the actual operating flow rate corresponding to any set flow rate value and the set flow rate value is less than ±2%, i.e., satisfying the formula: |(actual flow rate - set flow rate) / set flow rate|×100%<2%. A variable frequency speed-regulating centrifugal pump or a precision gear pump is preferred for the circulating pump, and the total flow rate of the system is controlled by adjusting the output speed of the circulating pump.

[0019] (3) Liquid temperature control unit The liquid temperature regulation unit is located between the circulating pump and the inlet of the dual-port microchannel liquid cooling assembly, and is used to regulate the temperature of the coolant entering the assembly. Preferably, the liquid temperature regulation unit is an integrated cooling and heating temperature control module. The temperature control range of the module must meet the following requirements: within the rated operating temperature range of the dual-port microchannel liquid cooling assembly (or the temperature regulation range involved in the diagnostic process), the absolute value of the absolute deviation between the actual coolant outlet temperature (i.e., the inlet temperature Tin of the dual-port microchannel liquid cooling assembly) corresponding to any set target temperature and the set target temperature is less than ±0.5℃, i.e., satisfying the formula: |actual coolant inlet temperature - set target temperature| < 0.5℃. This achieves linear and stable regulation of the coolant temperature, providing precise temperature control for heat loading.

[0020] (4) Filter A filter is installed between the liquid temperature control unit and the inlet of the dual-port microchannel liquid cooling assembly to intercept solid particulate impurities in the coolant. The filter is required to effectively intercept particles with a diameter of not less than 10μm, with an interception efficiency of not less than 99% (based on ISO4572 standard testing), to prevent particles from entering the microchannels and causing local blockage, leading to flow imbalance and misdiagnosis of faults.

[0021] (5) Back pressure regulating valve The back pressure regulating valve is located downstream of the liquid outlet of the dual-port microchannel liquid cooling assembly and is used to regulate the overall pressure level of the system. Preferably, an electrically operated high-precision back pressure valve is used. By adjusting the opening of the back pressure regulating valve, the static pressure of the fluid inside the dual-port microchannel liquid cooling assembly can be increased or decreased without significantly changing the total flow rate, thus achieving system pressure regulation.

[0022] (6) Bypass exhaust branch The bypass exhaust branch is used to quickly discharge air from the circulation loop during system startup and operation, eliminating the interference of air bubbles on flow measurement, pressure measurement, temperature measurement, and fault diagnosis.

[0023] 3. Multi-parameter sensing module The multi-parameter sensing module is used to acquire the system's fluid parameters, temperature parameters, and wetting signals in real time, providing a data foundation for subsequent baseline establishment, operating condition adjustment, and fault diagnosis. The multi-parameter sensing module is functionally divided into three units: a fluid parameter sensing unit, a temperature sensing unit, and a wetting sensing unit. The output signals of all sensing units are connected to the data processing and control module.

[0024] (1) Fluid parameter sensing unit The fluid parameter sensing module includes an inlet pressure sensor, an outlet pressure sensor, and a total flow sensor.

[0025] The inlet pressure sensor is used to collect the hydrostatic pressure Pin at the inlet of the dual-port microfluidic liquid cooling assembly in real time. The inlet pressure sensor is installed at the liquid inlet of the dual-port microfluidic liquid cooling assembly, close to the liquid inlet channel. Within the rated measurement range of the inlet pressure sensor, the maximum permissible absolute value of the error at any measurement point does not exceed ±0.2% of the rated range of the sensor, that is, it satisfies the formula: |(actual measured value - true value) / sensor rated range|×100%≤0.2%.

[0026] The outlet pressure sensor is used to collect the hydrostatic pressure Pout at the outlet of the dual-port microchannel liquid cooling assembly in real time. The outlet pressure sensor is installed at the liquid outlet of the assembly under test, close to the liquid outlet flow channel. The measurement accuracy of the outlet pressure sensor is the same as that of the inlet pressure sensor.

[0027] The total flow sensor is used to collect the total flow rate Q of the coolant entering the dual-port microchannel liquid cooling assembly in real time. The total flow sensor is installed upstream of the liquid inlet of the dual-port microchannel liquid cooling assembly and downstream of the filter. The total flow sensor is preferably a Coriolis mass flow meter or a high-precision turbine flow meter. Within the rated measurement range of the total flow sensor, the maximum permissible absolute value of the error at any measurement point does not exceed ±0.5% of the rated range of the sensor, that is, it satisfies the formula: |(actual measured value - true value) / sensor rated range|×100%≤0.5%.

[0028] (2) Temperature sensing unit The temperature sensing unit includes an inlet temperature sensor, an outlet temperature sensor, a near-end area outer wall temperature sensor, and a far-end area outer wall temperature sensor.

[0029] The inlet temperature sensor is used to collect the real-time temperature Tin of the coolant entering the dual-port microchannel liquid cooling assembly. The inlet temperature sensor is installed at the liquid inlet of the dual-port microchannel liquid cooling assembly, close to the liquid inlet channel. The inlet temperature sensor uses a PT1000-grade platinum resistance thermometer. Within the rated temperature measurement range of the inlet temperature sensor, the absolute value of the absolute deviation between the actual measured temperature value and the true temperature value of the measured medium at any measurement point is less than 0.2℃, that is, it satisfies the formula: |actual measured temperature value - true medium temperature value| < 0.2℃.

[0030] The outlet temperature sensor is used to collect the coolant temperature Tout of the dual-port microchannel liquid cooling assembly in real time. The outlet temperature sensor is installed at the outlet of the dual-port microchannel liquid cooling assembly, close to the outlet flow channel. The temperature measurement accuracy and selection of the outlet temperature sensor are completely consistent with those of the inlet temperature sensor.

[0031] The near-end area outer wall temperature sensor is used to acquire the wall temperature Tnear of the first outer wall surface of the dual-port microfluidic liquid cooling assembly in real time. The installation position of the near-end area outer wall temperature sensor corresponds to the near-end liquid supply area of ​​the microfluidic heat exchange zone, close to the inlet distribution chamber. The near-end area outer wall temperature sensor is preferably a surface-mount platinum resistance thermometer or a thermocouple. During installation, a highly thermally conductive insulating adhesive is filled between the temperature sensing element and the contact surface of the assembly outer wall to ensure accurate temperature measurement and fast response.

[0032] The distal region outer wall temperature sensor is used to acquire the wall temperature Tfar of the second outer wall surface of the dual-port microfluidic liquid cooling assembly in real time. The distal region outer wall temperature sensor is installed in the distal liquid supply area of ​​the microfluidic heat exchange zone, near the outlet manifold. The selection of the temperature sensing element, installation method, and installation process of the distal region outer wall temperature sensor are completely consistent with those of the near-end region outer wall temperature sensor, and both are located on the same measured plane to ensure consistent measurement references and eliminate measurement errors caused by installation differences.

[0033] (3) Wetting sensor unit The wetting sensing unit includes a primary wetting sensor and a secondary wetting sensor. The primary wetting sensor is installed in the primary capillary collection channel of the two-stage capillary exposure module, and the secondary wetting sensor is installed in the secondary exposure chamber of the two-stage capillary exposure module. Both are used to detect in real time whether the corresponding installation location is wetted by leaking liquid and output wetting signals (including dry-state switching signals, wet-state switching signals, or analog signals positively correlated with the wetting area). The primary and secondary wetting sensors are preferably interdigitated capacitive wetting sensors. Interdigitated capacitive wetting sensors have the characteristics of fast response speed, no contact loss, high sensitivity to trace liquids, strong anti-interference ability, and long service life, enabling effective detection of nanoliter-level trace amounts of coolant.

[0034] 4. Two-stage capillary exposure module The two-stage capillary exposure module is used to collect, restrict and retain, and guide the trace amounts of coolant seeping from the leak-sensitive interface in a targeted manner. It transforms the micro-leakage hidden inside the leak-sensitive interface and undetectable by external sensors into a wetting signal with clear temporal characteristics that can be repeatedly detected, providing a basis for distinguishing between micro-leakage and direct external leakage.

[0035] The two-stage capillary exposure module is located on the periphery of the potential structure interface and includes: a primary capillary collection channel, a transition flow restriction section, and a secondary exposure cavity.

[0036] (1) Primary capillary collection ditch Located on the outer periphery of the leakage-sensitive interface, the primary capillary collection trench extends along the contour of the interface and is adjacent to and surrounds it. The distance between the primary capillary collection trench and the leakage-sensitive interface is ≤2mm. This ensures that the trace amounts of coolant seeping from the leakage-sensitive interface are preferentially captured by the primary capillary collection trench before they migrate extensively under the influence of gravity and capillary force. The primary capillary collection trench has an open or semi-open microgroove structure. The cross-sectional shape of the trench structure is preferably rectangular, trapezoidal, or V-shaped. The dimensions of the trench structure (width and depth of the top opening) can be set between 50μm and 200μm to ensure that the trench structure has sufficiently strong capillary adsorption force, thereby actively adsorbing the trace amounts of coolant seeping from the structural interface, achieving directional collection of trace amounts of leaked liquid, and preventing the leaked liquid from spreading in an irregular direction.

[0037] To further enhance the capillary adsorption capacity of the primary capillary collection trench, the inner wall of the trench structure is preferably subjected to hydrophilic modification treatment, such as plasma hydrophilic modification or coating with a nano-hydrophilic coating, so that the contact angle between the inner wall of the trench structure and the coolant is less than 30°, ensuring the collection efficiency of trace amounts of leaked liquid.

[0038] As the first-stage capture and collection structure for micro-leakage, the primary capillary collection channel plays a crucial role in distinguishing the source of the leaking liquid. Only trace amounts of coolant seeping from the leak-sensitive interface will preferentially enter the primary capillary collection channel, thereby triggering the primary wetting sensor to activate first. External splashes or leaks from other locations will not preferentially enter the primary capillary collection channel to trigger the primary wetting sensor, thus effectively eliminating external interference.

[0039] (2) Transitional flow restriction section The transition flow-limiting section is a fluid channel connecting the primary capillary collection channel and the secondary exposure cavity. The flow cross-sectional area of ​​the fluid channel is smaller than the total flow cross-sectional area of ​​the primary capillary collection channel and the total flow cross-sectional area of ​​the secondary exposure cavity, forming a flow-limiting structure with fluid resistance. The transition flow-limiting section can adopt a narrow slit structure, a microporous structure, or a capillary bundle structure. The dimensions of the transition flow-limiting section (width and depth of the top opening) are preferably 20 μm to 100 μm. The core function of the transition flow-limiting section is to construct a fluid resistance barrier between the primary capillary collection channel and the secondary exposure chamber, achieving a temporal separation of the leakage fluid's "collection first, exposure later" process. The core mechanism is as follows: the trace amount of coolant seeping from the leak-sensitive interface is first adsorbed and collected by the primary capillary collection channel. Because the flow resistance of the transition flow-limiting section is greater than that of the primary capillary collection channel, some of the coolant adsorbed and collected by the primary capillary collection channel cannot immediately enter the secondary exposure chamber and will first accumulate in the primary capillary collection channel. Only when the volume of coolant in the primary capillary collection channel accumulates to form a sufficient capillary pressure difference, or when changes in operating conditions cause changes in the surface tension and migration state of the coolant, will the leaking coolant enter the secondary exposure chamber through the transition flow-limiting section. The transition flow-limiting section allows for the temporal separation of the "seepage and collection" process from the "exposure" process of the leaking fluid, thus forming a temporal characteristic where the primary wetting sensor triggers first, followed by the secondary wetting sensor. This temporal characteristic can serve as one of the criteria for identifying micro-leakage.

[0040] (3) Secondary exposure cavity The secondary exposure chamber is located at the end of the transition flow-limiting section away from the primary capillary collection channel, situated downstream of the primary capillary collection channel along the continuous path of the leaking liquid's capillary migration direction. The secondary exposure chamber serves as the final exposure point for the trace amounts of coolant that leak from the structural interface, first collected by the primary capillary collection channel, and then restricted by the transition flow-limiting section. Its structure can be configured as an open cavity structure. The volume of this open cavity structure is larger than the total volume of the primary capillary collection channel; the flow resistance inside the open cavity structure is less than that of the transition flow-limiting section, thus ensuring that the coolant can spread rapidly after entering the secondary exposure chamber, facilitating detection of the coolant by the secondary wetting sensor. The core function of the secondary exposure chamber is to provide a stable detection space for the final exposure of the leaking liquid. Its open cavity structure's capacity to hold the leaking liquid maintains the wetting state within the open cavity structure, achieving a stable output of the leak signal.

[0041] It should be further explained that: the primary wetting sensor is directly attached to or integrated into the inner wall or bottom of the primary capillary collection channel, ensuring that any trace amount of coolant entering the channel can be quickly detected; the secondary wetting sensor is arranged at the bottom of the secondary exposure chamber, ensuring that coolant entering the secondary exposure chamber can be stably detected.

[0042] 5. Data processing and control module The data processing and control module, the external circulation condition adjustment module, and the multi-parameter sensing module are all connected via electrical circuits to work together to complete the entire process of diagnostic control and data processing.

[0043] The data acquisition and control module includes: (1) Data acquisition unit The data acquisition unit is used to acquire fluid parameters transmitted by the fluid parameter sensing unit in real time (including the hydrostatic pressure Pin at the inlet of the dual-port microfluidic liquid cooling component, the hydrostatic pressure Pout at the outlet of the dual-port microfluidic liquid cooling component, and the total flow rate Q of the coolant entering the component under test), temperature parameters transmitted by the temperature sensing unit in real time (including the coolant temperature Tin entering the dual-port microfluidic liquid cooling component, the coolant temperature Tout flowing out of the dual-port microfluidic liquid cooling component, the wall temperature Tnear of the first outer wall of the dual-port microfluidic liquid cooling component, and the wall temperature Tfar of the second outer wall of the dual-port microfluidic liquid cooling component), and wetting signals transmitted by the wetting sensing module in real time (including dry-state switch signals, wet-state switch signals, or analog signals). Furthermore, it performs analog-to-digital conversion, noise reduction filtering, and synchronous latching on the fluid parameters, temperature parameters, and wetting signals to eliminate signal interference and transmission delay, ensuring the authenticity, synchronization, and accuracy of the acquired data, and providing a raw data source for subsequent data processing.

[0044] (2) Operating condition control unit The operating condition control unit has a built-in standardized timing logic for the entire process of diagnosing microleakage of the dual-port microchannel liquid cooling component. The standardized timing logic includes, in sequence: system initialization and steady-state preparation, establishing a flow balance baseline, controlled temperature-pressure active excitation, and multi-dimensional fault discrimination and classification.

[0045] 1) System initialization and steady-state preparation Before performing flow balancing and microleakage diagnosis on the dual-port microfluidic liquid cooling assembly, it is necessary to fill the system with liquid, vent the air, and establish the initial steady state of the system. The purpose is to eliminate residual air bubbles in the system, eliminate turbulence in the flow field during subsequent execution stages, and eliminate the initial drift caused by multi-parameter sensing modules and system parameters. This ensures that there are clean, stable, and repeatable initial operating conditions when establishing the balancing baseline, laying the foundation for the accuracy and reliability of the entire diagnostic process.

[0046] The standardized timing logic for system initialization is as follows: First, start the circulation pump of the external circulation condition adjustment module to slowly fill the closed coolant circulation loop with coolant (the circulation pump speed can be set to 10%~30% of the rated minimum speed), allowing the coolant to slowly fill the entire closed coolant circulation loop at a low flow rate. Setting the circulation pump speed to 10%~30% of the rated minimum speed is to adapt to the internal microchannel size of the dual-port microchannel liquid cooling assembly. Specifically, the internal flow channel size of the dual-port microchannel liquid cooling assembly is small, and there are many corners, blind ends, and distribution chamber edges, which are prone to trapping air bubbles. If the coolant flow rate is too fast, the air in the closed coolant circulation loop will be dispersed into a large number of micron-sized bubbles under the rapid impact of the coolant. These micron-sized bubbles are easy to adhere to the inner wall of the microchannel or get stuck in the dead corners of the flow channel and are difficult to expel, which will lead to abnormalities in flow measurement, pressure drop measurement, and temperature measurement, and may even be misjudged as blockage or leakage faults. Therefore, in this embodiment, by setting the speed of the circulating pump to 10% to 30% of the rated minimum speed, the coolant is slowly propelled within the closed coolant circulation loop, thereby driving the air in the closed coolant circulation loop toward the outlet and avoiding the formation of dispersed micron-sized bubbles.

[0047] After low-speed filling is completed, multiple rounds (≥2 rounds) of venting are performed through the bypass venting branch of the external circulation condition adjustment module to remove residual air bubbles from the closed coolant circulation loop. Each round of venting includes: a low-speed circulation phase, a settling phase, and a venting phase. The low-speed circulation phase can be set to 5-10 minutes, with the purpose of using the slow-flowing coolant to carry air bubbles in the closed coolant circulation loop towards higher points in the pipes, the bypass branch, and the reservoir. The settling phase can be set to 2-5 minutes, with the purpose of allowing dispersed small air bubbles to aggregate during the settling process, forming larger air bubbles that are more easily carried away by the fluid. The venting phase can be set to 1-3 minutes, with the large air bubbles being discharged into the reservoir by opening the venting control valve of the bypass branch. Using the above multiple rounds of venting improves the efficiency of air bubble removal, thereby eliminating interference from air bubbles in subsequent diagnostics.

[0048] After venting, adjust the system operating conditions to the light load range corresponding to the rated operating range of the dual-port microchannel liquid cooling component (typically 30%~50% of rated flow, 20%~40% of rated pressure, and ambient temperature range, depending on the rated parameters of the dual-port microchannel liquid cooling component). Allow the system to run continuously and stably under this condition for 10~30 minutes to ensure that the flow field and temperature field reach a stable state. Simultaneously, collect fluid and temperature parameters at a preset sampling frequency, and calculate the mean and natural fluctuation range of each parameter based on the 3σ statistical principle to establish the corresponding initial stable fluctuation band. The basis for establishing the initial stable fluctuation band using the 3σ statistical principle is that, under the premise that normal data conforms to a normal distribution, 99.73% of the valid data will fall within the interval [μ-3σ, μ+3σ]. This interval can objectively and accurately reflect the natural fluctuation range of each parameter under normal stable conditions without faults or interference. In subsequent microleakage diagnosis procedures, when judging whether any measured parameters show abnormal deviations, the corresponding initial stable fluctuation band is used as the benchmark. It should be further explained that the initial stable fluctuation band is a dynamic benchmark of the system's own steady-state characteristics. It can effectively avoid misjudgments caused by factors such as individual differences in the processing of different tested components and differences in the state of the external circulation system (such as pipeline resistance and pump performance fluctuations). It can improve the adaptability and accuracy of flow balancing and micro-leakage diagnosis methods.

[0049] After establishing the initial stable fluctuation band, the initial stable state determination is performed. When the fluctuations of all fluid parameters and all temperature parameters within multiple (≥2) consecutive sampling time windows are within the corresponding initial stable fluctuation band range, and the wetting signals output by the primary wetting sensor and the secondary wetting sensor are dry switching signals throughout the process, the system is determined to have entered the initial stable state and can proceed to the equalization baseline establishment process.

[0050] 2) Establish a traffic balancing baseline After system initialization and steady-state preparation, a flow balance baseline can be established. The purpose is to select the optimal operating point for the current dual-port microchannel liquid cooling assembly, ensuring the most uniform flow distribution and the most stable flow and temperature fields. This selected operating point is used to establish a standardized diagnostic benchmark, thereby eliminating interference from individual component differences, uneven flow distribution, and operating condition fluctuations on subsequent control logic. This ensures that subsequent control logic is based on a unified and comparable benchmark. It should be noted that this embodiment establishes corresponding standardized diagnostic benchmarks for different dual-port microchannel liquid cooling assemblies. The purpose is to accommodate individual differences in processing, assembly, materials, flow channel resistance distribution, and heat transfer boundary conditions among different components. Only by finding the operating point where the current dual-port microchannel liquid cooling assembly has the most uniform flow distribution and the most stable flow and temperature fields within the current system can the corresponding baseline envelope have diagnostic significance.

[0051] The standardized timing logic for establishing a traffic balancing baseline is as follows: First, within the rated operating range (rated flow rate, rated pressure, rated temperature) of the dual-port microfluidic liquid cooling assembly, select multiple sets (≥5 sets) of candidate operating conditions. Each candidate operating condition corresponds to a combination of circulating pump speed (i.e., total flow rate) and back pressure regulating valve opening (i.e., system pressure). The selected candidate operating conditions need to cover multiple flow ranges and multiple pressure ranges to facilitate finding the optimal operating condition.

[0052] Subsequently, the system is adjusted to the operating condition corresponding to each group of candidate operating points. After the operating condition stabilizes, it is kept in steady state for 3 to 10 minutes, and steady-state parameters (including fluid parameters, temperature parameters and wetting signals) under the operating condition are collected simultaneously.

[0053] After the steady-state parameters of all candidate operating points are collected, for each candidate operating point, the near-far thermal response difference ΔTw is calculated based on the steady-state parameters. The near-far thermal response difference ΔTw is the difference between the outer wall temperature of the near-end region and the outer wall temperature of the far-end region of the dual-port microchannel liquid cooling assembly, used to characterize the uniformity of flow distribution within the microchannels of the dual-port microchannel liquid cooling assembly. The formula for calculating the near-far thermal response difference ΔTw is: ΔTw = |Tnear − Tfar|. All candidate operating points are sorted by flow balance in ascending order of the near-far thermal response difference ΔTw, establishing a candidate operating point sequence. The mechanism of flow equalization sorting is as follows: When the coolant flows within the microchannel, it continuously exchanges heat with the heat source being cooled, and the coolant temperature gradually increases along the flow direction. If the flow distribution within the microchannel is uniform, the temperature distribution throughout the heat exchange zone will remain uniform, and the near-far thermal response difference will be small. However, if the flow distribution is uneven, or if there is local blockage or air entrapment, the flow rate in the microchannel of the near-end supply area will be large, while the flow rate in the microchannel of the far-end supply area will be small. The coolant temperature rise in the far-end supply area will be significantly higher than that in the near-end, the outer wall temperature difference will be greatly amplified, and the value of the near-far thermal response difference will increase significantly. Therefore, the near-far thermal response difference can be used to indirectly monitor the flow distribution state inside the microchannel of the dual-port microchannel liquid cooling assembly, without the need to place sensors inside the microchannel to obtain the equilibrium state of the internal flow field.

[0054] After the flow balance sorting is completed, the candidate operating points in the candidate operating point sequence are visited sequentially starting from the first candidate operating point. During the visit, the operating conditions of the candidate operating points are verified. Specifically, the operating condition verification is performed to check whether the currently visited candidate operating point simultaneously meets conditions 1 and 2. Condition 1 is that under this candidate operating point, the total coolant flow rate Q, the system pressure drop ΔP, and the hydrostatic pressure Pin at the inlet of the dual-port microchannel liquid cooling component are all within the rated operating range of the dual-port microchannel liquid cooling component. Condition 2 is that under this candidate operating point, the wetting signals output by the primary and secondary wetting sensors are all dry-state switching signals throughout the process. If conditions 1 and 2 cannot be met simultaneously, the next candidate operating point is visited sequentially, and the operating condition verification is performed on the candidate operating point during the visit, until a candidate operating point that can simultaneously meet conditions 1 and 2 is visited. This candidate operating point is then used as the balance baseline operating point for subsequent flow balance and leakage diagnosis.

[0055] After determining the equilibrium baseline operating point, maintain stable operation of the system under the corresponding operating conditions for 5-15 minutes, and collect steady-state operating parameters (including total coolant flow rate Q, system pressure drop ΔP, inlet and outlet temperature rise ΔT, and near-far thermal response difference ΔTw). Perform eigenvalue calculations on the total coolant flow rate Q, system pressure drop ΔP, inlet and outlet temperature rise ΔT, and near-far thermal response difference ΔTw. The eigenvalue calculation includes: calculating the steady-state mean μ. base and standard deviation σ base The inlet and outlet temperature rise ΔT refers to the difference between the coolant outlet temperature and the coolant inlet temperature of the dual-outlet microchannel liquid cooling assembly, calculated using the formula ΔT = Tout − Tin. Then, with [μ... base -3σ base , μ base +3σ base This serves as the baseline normal range for each steady-state operating data, forming a balanced baseline envelope. All steady-state operating parameters and dry-state references are permanently stored as the sole reference for subsequent fault diagnosis processes. The dry-state reference refers to the stable, moisture-free raw signals (including dry-state switch signals or corresponding dry-state analog signals) output by the primary and secondary wetting sensors.

[0056] 3) Controlled temperature-pressure active excitation Controlled temperature-pressure active excitation is a process that actively constructs a microleakage trigger window within the rated operating range of the dual-port microchannel liquid cooling assembly by coupling controlled pressure and temperature. This makes the microleakage that was originally hidden and discontinuous under steady state explicit, providing complete characteristic data for subsequent leakage identification.

[0057] The microleakage described in this embodiment refers to leakage with strong operating condition dependence, that is, leakage that only occurs under specific operating conditions involving the coupling of pressure, temperature, and thermal expansion stress. If the system only operates under normal steady-state conditions, this microleakage will not be apparent, easily leading to missed detection. Therefore, through controlled temperature-pressure active excitation, the operating conditions used to trigger micro-crack expansion can be reproduced under safe operating conditions, thereby making the hidden, discontinuous microleakage visible.

[0058] The standardized timing logic for controlled temperature-pressure active excitation is as follows: First, a baseline reset is performed—before executing controlled temperature-pressure active excitation, the system is allowed to run stably for 2-5 minutes at the equilibrium baseline operating point to confirm that all steady-state operating parameters are within the normal range of the equilibrium baseline envelope, and that the wetting sensor status signals output by the primary and secondary wetting sensors are dry switching signals throughout the process. This ensures that the initial state of the system before controlled temperature-pressure active excitation is completely consistent with the baseline state, eliminating the influence of the initial state deviation on the diagnostic results.

[0059] After baseline reset, controlled pressure is applied first. While maintaining a stable total coolant flow rate Q, the opening of the back pressure regulating valve is adjusted to allow the overall system pressure to rise linearly and slowly over time. The pressure loading rate is controlled at 5% to 10% per minute of the rated maximum operating pressure of the dual-port microchannel liquid cooling assembly. The final target pressure does not exceed 95% of the rated maximum operating pressure of the dual-port microchannel liquid cooling assembly. The entire loading process is conducted within the safe operating range of the dual-port microchannel liquid cooling assembly. Furthermore, during controlled pressure loading, the speed of the circulating pump is simultaneously fine-tuned to compensate for the flow rate changes caused by the increase in back pressure, ensuring that the fluctuation range of the total coolant flow rate Q does not exceed ±5% of the corresponding baseline value, thereby avoiding interference from flow rate changes in subsequent parameter comparisons. For example, the rotational speed is increased by 1% to 3% each time, and after the total coolant flow rate Q stabilizes, the total coolant flow rate Q is compared with the baseline flow rate again. If the total coolant flow rate Q is higher than ±5% of the baseline flow rate, the circulation pump speed is gradually reduced in small steps (no more than 1% to 5% of the rated speed of the circulation pump) until the total coolant flow rate Q returns to the ±5% fluctuation range of the baseline value, thereby achieving closed-loop speed regulation with constant flow rate. It should also be noted that the higher the hydrostatic pressure inside the dual-port microchannel liquid cooling component, the greater the force on the leakage-sensitive interface, and the easier it is to cause the micro-gap to open and form a micro-leakage channel. In this embodiment, micro-leakage is triggered by applying controlled pressure to the system, providing a stable pressure basis for subsequent heat loading.

[0060] Once the controlled pressure is applied until the system pressure reaches the target value and stabilizes, a controlled thermal loading operation is then performed. This involves increasing the temperature of the coolant entering the dual-port microchannel liquid cooling assembly via a liquid temperature regulation unit, establishing a pressure-temperature coupled operating window. The coolant's heating rate must be controlled between 2°C / min and 5°C / min, and the target coolant temperature should not exceed 95% of the rated maximum operating temperature of the dual-port microchannel liquid cooling assembly. During the controlled thermal loading process, the system pressure and the total coolant flow rate Q must remain stable. It should be noted that the thermal expansion coefficients of the capping layer, substrate layer, seals, and bonding materials of the dual-port microchannel liquid cooling assembly differ. When the coolant temperature rises, the different amounts of thermal expansion in each part generate additional thermal stress at leakage-sensitive interfaces, causing the originally closed micro-gap to open and forming a leakage channel. Therefore, performing a controlled thermal loading operation on top of the controlled pressure loading operation can maximize the triggering of micro-leakage.

[0061] Once the system pressure and temperature reach the preset target values ​​and the system is running stably, it enters the temperature-pressure coupling condition maintenance stage—maintaining the system at the target pressure and temperature for 5 to 30 minutes. The purpose of temperature-pressure coupling condition maintenance is to: (1) provide sufficient opening time for the micro-gap, allowing the leakage liquid to have enough time to seep out from the micro-gap; (2) provide sufficient migration time for the seeping micro-leakage liquid, allowing the leakage liquid to first migrate along the structural interface to the primary capillary collection channel and be detected by the primary wetting sensor, and then allow the leakage liquid to gradually enter the secondary exposure chamber through the transition flow restriction section and be detected by the secondary wetting sensor; (3) allow the system to fully accumulate leakage signals, avoiding leakage detection due to insufficient leakage volume and insufficient migration time of the leakage liquid. In addition, during the temperature-pressure coupling operation phase, it is also necessary to continuously stabilize the pressure and temperature of the system to ensure that the amplitude of the pressure band and the fluctuation of the temperature do not exceed ±2% of the target value. At the same time, the measurement data output by all multi-parameter sensing modules are collected in real time throughout the process, and the triggering sequence of the output signals of the primary and secondary wetting sensors is monitored.

[0062] After the temperature-pressure coupling condition maintenance phase ends, a controlled recovery operation is performed. First, the coolant temperature is reduced at a rate consistent with the coolant's heating rate. Once the coolant temperature returns to the baseline value, the system pressure is reduced at a rate consistent with the pressure increase rate, ultimately restoring the system operating conditions completely to the condition corresponding to the equilibrium baseline operating point. The controlled recovery operation must employ a linear and slow adjustment method throughout to avoid disturbances in the flow and temperature fields caused by sudden changes in operating conditions. Simultaneously, measurement data from all multi-parameter sensor modules are collected in real-time throughout the process, monitoring the hysteresis and tailing characteristics of the output signals from the primary and secondary wetting sensors. It should be noted that for microleakage, when the temperature and pressure drop, the micro-gap will close again due to stress release, stopping the leakage. However, the leaked coolant will remain in the primary capillary collection channel, the transition flow restriction section, and the secondary exposure cavity, and continue to migrate and spread. This results in a hysteresis and tailing phenomenon where "the system has completed the recovery and returned to the initial stable state, but the primary and secondary wetting sensors continue to output wetting signals; even during the recovery phase, the secondary wetting sensor is only triggered for the first time." Therefore, the hysteresis and tailing characteristics of the wetting signal can be extracted through controlled recovery operations, and these characteristics can be used as distinguishing features between microleakage and other faults.

[0063] 4) Multidimensional Fault Identification and Classification Multidimensional fault identification and classification is based on all parameter data collected in the preceding steps. First, the boundary between non-leakage and leakage anomalies is defined by whether a wetting signal is collected. Then, different fault types are accurately identified through multidimensional features. Finally, the classification and diagnosis results of the operating status are completed, thereby reducing the false positive and false negative rates from the root.

[0064] The standardized timing logic for multidimensional fault identification and classification is divided into: non-leakage anomaly identification logic, direct external leakage anomaly identification logic, and micro-leakage anomaly identification logic.

[0065] <1> The logic for non-leakage anomaly detection is as follows: Throughout the entire "temperature-pressure excitation, temperature-pressure coupling condition maintenance, and controlled recovery" timing logic, if the wetting signals output by both the primary and secondary wetting sensors are dry-state switching signals, then micro-leakage anomalies can be directly ruled out. The mechanism for non-leakage anomaly detection is as follows: Micro-leakage is essentially coolant seeping from the inside of the microchannel to the outside, which will inevitably be captured by the two-stage capillary exposure units, triggering the primary and secondary wetting sensors to output wet-state switching signals. Conversely, non-leakage anomalies output dry-state switching signals from the primary and secondary wetting sensors. Therefore, it is possible to fundamentally avoid misjudging non-leakage faults such as flow imbalance, blockage, and air entrapment as micro-leakage faults.

[0066] Furthermore, based on the variation characteristics of the near-far thermal response difference ΔTw, system pressure drop ΔP, and total coolant flow rate Q, the fault types of non-leakage anomalies can be further subdivided: If the near-far thermal response difference ΔTw continuously exceeds the normal range of the equilibrium baseline envelope, the total coolant flow rate Q decreases compared to the baseline value and the decrease exceeds the lower limit of the baseline range, while the system pressure drop ΔP increases compared to the baseline value and the increase exceeds the upper limit of the baseline range, then the current fault type can be determined to be a local blockage or particulate deposition anomaly. The core mechanism for this type of anomaly detection is: when local blockage or particulate deposition occurs in the microchannel, it will cause a significant increase in the flow resistance of the microchannel, and the flow will be distributed to other channels. The overall flow distribution uniformity of the dual-port microchannel liquid cooling assembly is disrupted, resulting in an increase in the near-far thermal response difference ΔTw. At the same time, the overall flow resistance of the dual-port microchannel liquid cooling assembly increases. With the pump speed unchanged, the total coolant flow rate Q will decrease, and the system pressure drop ΔP will increase. Moreover, the entire process will not trigger the output of wet switching signals from the primary and secondary wetting sensors, thus having a clear boundary with the leakage fault.

[0067] If the near-far thermal response difference ΔTw exceeds the normal range of the equilibrium baseline envelope and is accompanied by irregular fluctuations, while the total coolant flow rate Q and system pressure drop ΔP also exhibit unstable fluctuations, and the inlet and outlet temperature rise ΔT shows synchronous irregular fluctuations, then it can be determined that the system has gas entrainment or gas evolution anomalies. The core mechanism for this type of anomaly detection is: when there are residual bubbles in the system, or when the coolant precipitates dissolved gas during the heating process, the bubbles will flow with the fluid in the microchannel, causing a reduction in the flow area and a sudden change in flow resistance in the local channel, which in turn leads to irregular fluctuations in flow rate, pressure, and temperature parameters. At the same time, it will also disrupt the uniformity of flow distribution, resulting in an abnormal near-far thermal response difference ΔTw. However, the bubbles will not cause coolant leakage, so they will not trigger the output of wet switching signals from the primary and secondary wetting sensors.

[0068] <2> The common logic for identifying direct external leakage anomalies is as follows: During the entire process of temperature and pressure excitation-holding-recovery, if the primary or secondary wetting sensor outputs a wet-state switching signal, the leakage anomaly identification process begins. Through timing characteristics, hysteresis characteristics, and reproducibility verification, direct external leakage is distinguished from micro-leakage. The identification process for direct external leakage anomalies is as follows: First, the core features that trigger the output of wet switching signals from the primary and secondary wetting sensors throughout the entire process are extracted. These features include the triggering sequence, the triggering time interval Δt, the corresponding operating condition stage at the time of triggering, and the continuous state of the wet switching signal after the operating condition recovers. Then, based on these core features, direct external leakage anomalies are identified. Specifically, if any of the following characteristics are present, it can be determined as a direct external leakage anomaly: 1) The time difference Δt between the triggering of the output wet switching signals from the primary and secondary wetting sensors is less than a preset time threshold (preferably 10 seconds); 2) The secondary wetting sensor outputs a wet switching signal before the primary wetting sensor (which does not conform to the timing characteristics of the output wet switching signals from the primary and secondary wetting sensors); 3) The primary and secondary wetting sensors output wet switching signals at the initial stage of pressure loading, and the signal strength continuously increases with the loading process, accompanied by a continuous and irregular increase in the total coolant flow rate Q and a continuous and irregular decrease in the system pressure drop ΔP. The core mechanism of this type of anomaly detection is as follows: Direct external leakage is caused by a through-hole rupture or large-flow leakage in the sealing structure of the dual-port microfluidic liquid cooling assembly. The coolant will quickly fill the entire leakage area, and the primary capillary collection channel and the secondary exposure chamber will be simultaneously wetted by the leaked coolant. Therefore, the time difference Δt between the output wet switching signals of the primary and secondary wetting sensors will be less than the preset time threshold. If the leakage location is far from the primary collection channel, the leaked coolant will directly diffuse into the secondary exposure chamber, and the secondary wetting sensor may even output a wet switching signal before the primary wetting sensor (which does not conform to the timing characteristics of the output wet switching signals of the primary and secondary wetting sensors, thus enabling clear differentiation).

[0069] After ruling out direct external leakage anomalies, the core characteristics of microleakage are then determined—if both the first and second criteria are met, it can be identified as microleakage.

[0070] The first criterion is timing characteristics: the primary wetting sensor outputs a wet switching signal before the secondary wetting sensor, and the time difference Δt between their output wet switching signals is greater than a preset time threshold. Specifically, the primary wetting sensor outputs its wet switching signal during the hot loading stage or the temperature-pressure coupling holding stage, while the secondary wetting sensor outputs its wet switching signal during the later stages of the holding stage or the controlled recovery stage. This timing characteristic is direct, observable physical evidence of microleakage, determined by the structure of the two-stage capillary exposure unit and the microleakage mechanism. For microleakage, the leaking fluid seeps out in a small amount and slowly from the leakage-sensitive interface of the adjacent primary capillary collection channel. Therefore, it will inevitably be captured by the primary collection channel first, triggering the primary wetting sensor to output a wet switching signal. Due to the flow resistance barrier of the transition flow limiting section, the small amount of leaking fluid cannot immediately enter the secondary exposure chamber. It needs to accumulate to a certain amount in the primary channel before it can overcome the flow resistance and enter the secondary exposure chamber. Therefore, the secondary wetting sensor outputs a wet switching signal with a time lag, especially during the recovery phase. Although the micro-gap has closed and the leakage has stopped, the leaked coolant will continue to migrate. Therefore, the phenomenon that the secondary wetting sensor only outputs a wet switching signal when the operating condition drops will occur.

[0071] The second primary criterion is the hysteresis and tailing characteristic: when the system's pressure and temperature conditions fully recover to the equilibrium baseline operating point, the primary wetting sensor will continuously output a wet switching signal before the secondary wetting sensor, and this signal will not disappear as the operating conditions recover, thus resulting in hysteresis and tailing of the wetting signal. The core mechanism of this characteristic is that microleakage is short-term and discontinuous, occurring only under temperature-pressure coupling conditions. When the operating conditions recover, the micro-gap closes, and microleakage stops. However, the coolant that has already seeped out of the leakage-sensitive interface and into the two-stage capillary exposure units will not disappear but will continue to remain in the primary collection channel and the secondary exposure chamber, continuously triggering the primary and secondary wetting sensors to output wet switching signals, thus causing hysteresis and tailing of the wetting signal.

[0072] After completing all the above leakage anomaly identification processes, the operating status of the dual-port microfluidic liquid cooling assembly can be divided into four categories, and corresponding diagnostic results can be output: The first category is the normal equilibrium state, that is, all sensor parameters are always within the equilibrium baseline envelope range, the primary and secondary wetting sensors output dry switching signals throughout the process, and there is no leakage anomaly; the second category is the non-leakage anomaly of flow imbalance or blockage, that is, the remote thermal response difference ΔTw, system pressure drop ΔP, and total coolant flow rate Q are continuously abnormal, but the primary and secondary wetting sensors output dry switching signals throughout the process; the third category is the direct external leakage anomaly, that is, the time difference Δt between the output wet switching signals of the primary and secondary wetting sensors is less than the preset time threshold, which is judged as a continuous, high-flow direct external leakage anomaly; the fourth category is the micro-leakage anomaly, that is, if the first and second criteria above are met, it can be judged as an early micro-leakage fault.

[0073] Example 2: This example provides a diagnostic method based on the microleakage diagnostic system for the dual-port microchannel liquid cooling assembly described in Example 1. The method is executed in the following order: "system initialization and steady-state preparation, candidate operating point setting and balanced baseline operating point screening—balanced baseline envelope establishment, controlled pressure loading and controlled heat loading, operating condition maintenance and controlled recovery, non-leakage anomalies, direct external leakage anomalies, and microleakage anomaly discrimination." Through the above steps, flow imbalance / blockage, system gas entrainment or gas evolution, direct external leakage, and operating condition-dependent microleakage of the dual-port microchannel liquid cooling assembly within its rated safe operating range can be distinguished.

[0074] In this embodiment, the tested object is a single-inlet, single-outlet, dual-port microfluidic liquid cooling assembly. The diagnostic device includes the dual-port microfluidic liquid cooling assembly, an external circulation condition adjustment module, a multi-parameter sensing module, a two-stage capillary exposure module, and a data processing and control module. The external circulation condition adjustment module provides circulating coolant and adjusts the total flow rate, system pressure, and coolant temperature. The multi-parameter sensing module collects inlet pressure, outlet pressure, total flow rate, inlet temperature, outlet temperature, near-end region outer wall temperature, far-end region outer wall temperature, and wetting signals from the primary and secondary wetting sensors. The two-stage capillary exposure module includes a primary capillary collection channel, a transition flow-limiting section, and a secondary exposure cavity. The primary wetting sensor is located in the primary capillary collection channel, and the secondary wetting sensor is located in the secondary exposure cavity. The near-end region outer wall temperature sensor is located on the side of the microfluidic heat exchange zone near the inlet distribution cavity, and the far-end region outer wall temperature sensor is located on the side of the microfluidic heat exchange zone near the outlet manifold. Both are on the same measured plane and installed in the same manner.

[0075] The method steps in this embodiment are as follows.

[0076] First, perform system initialization and steady-state preparation steps. Start the circulation pump in the external circulation condition adjustment module to slowly fill the closed coolant circulation loop with coolant at 10%–30% of its rated minimum speed, allowing the circulating coolant to slowly fill the entire closed circulation loop. After the low-speed filling is complete, perform at least two rounds of venting operations through the bypass venting branch. Each round of venting operations includes a low-speed circulation phase, a static dwell phase, and a venting phase. The low-speed circulation phase lasts 5–10 minutes, the static dwell phase lasts 2–5 minutes, and the venting phase lasts 1–3 minutes. After venting, adjust the system to a light-load condition within the rated operating range of the dual-port microchannel liquid cooling component, allowing the system to run continuously and stably for 10–30 minutes. Collect inlet pressure, outlet pressure, total flow rate, inlet temperature, outlet temperature, near-end region outer wall temperature, and far-end region outer wall temperature at a preset sampling frequency. Based on the steady-state operating data, calculate the mean and natural fluctuation range of each parameter to establish the corresponding initial stable fluctuation band. When all fluid parameters and temperature parameters within multiple consecutive sampling time windows are within their corresponding initial stable fluctuation ranges, and both the primary and secondary wetting sensors continuously output dry-state signals, the system is deemed to have entered a qualified initial stable state. This step is used to eliminate interference from residual bubbles, initial flow field disturbances, and temperature drift on subsequent diagnostic procedures.

[0077] After the system reaches its initial stable state, the steps of setting candidate operating points and screening baseline operating points are performed. Specifically, multiple sets of candidate operating points are set within the rated operating range of the dual-port microfluidic liquid cooling assembly. Each set of candidate operating points consists of a set of circulating pump speeds and a set of back pressure regulating valve openings, thus corresponding to a set of total flow and system pressure combinations. The number of candidate operating points is preferably no less than 5 sets, covering multiple flow ranges and multiple pressure ranges. The system is sequentially adjusted to the operating conditions corresponding to each candidate operating point. After the operating conditions stabilize, it is kept in steady-state operation for 3–10 minutes, and the inlet pressure, outlet pressure, total flow, inlet temperature, outlet temperature, near-end region outer wall temperature, far-end region outer wall temperature, and wetting status of the primary and secondary wetting sensors are collected simultaneously at the candidate operating point. Subsequently, the near-end and far-end thermal response difference ΔTw at the candidate operating point is calculated based on the near-end region outer wall temperature Tnear and the far-end region outer wall temperature Tfar. The calculation formula is: ΔTw=|Tnear−Tfar|. The near-far thermal response difference is used to characterize the uniformity of flow distribution in the microchannels within the dual-port microchannel liquid cooling assembly. A smaller ΔTw indicates a more uniform flow distribution and a more stable outer wall temperature distribution. Then, the candidate operating points are sorted in ascending order of near-far thermal response difference to form a candidate operating point sequence.

[0078] After forming a sequence of candidate operating points, operating condition verification is performed sequentially starting from the highest-ranked candidate operating point. During operating condition verification, the following conditions are simultaneously considered: First, the total coolant flow rate Q, system pressure drop ΔP, and hydrostatic pressure Pin at the inlet of the dual-port microchannel liquid cooling component at the current candidate operating point are within the rated operating range of the dual-port microchannel liquid cooling component; second, the wetting signals output by the primary and secondary wetting sensors are both dry signals. When the current candidate operating point simultaneously meets the above conditions, it is determined as the equilibrium baseline operating point; if the current candidate operating point does not simultaneously meet the above conditions, the next candidate operating point in the ranking is selected for continued operating condition verification until an equilibrium baseline operating point is found. Through this selection method, the baseline operating condition with the most balanced flow distribution, the most stable temperature field, and no leakage can be determined under the current tested dual-port microchannel liquid cooling component, the current external circulation system, and the current installation state.

[0079] After the baseline operating points are selected, the baseline envelope establishment step is performed. The system is kept running stably for 5–15 minutes under the operating conditions corresponding to the baseline operating points, and steady-state total flow rate Q, steady-state system pressure drop ΔP, steady-state inlet and outlet temperature rise ΔT, and steady-state near-far thermal response difference ΔTw are collected. The inlet and outlet temperature rise ΔT is the difference between the coolant outlet temperature Tout and the coolant inlet temperature Tin, i.e., ΔT = Tout − Tin. The steady-state mean μbase and standard deviation σbase of the steady-state total flow rate Q, steady-state system pressure drop ΔP, steady-state inlet and outlet temperature rise ΔT, and steady-state near-far thermal response difference ΔTw are calculated respectively. Subsequently, the interval [μbase − 3σbase, μbase + 3σbase] for each parameter is used as the baseline normal range for each parameter, and the baseline normal ranges of each parameter are used together to form the baseline envelope. Simultaneously, the original output signals of the primary and secondary wetting sensors under dry conditions are stored and used as the dry-state reference for subsequent fault diagnosis. The equilibrium baseline envelope is used to characterize the normal steady-state parameter boundary of the dual-port microchannel liquid cooling component under the current system state, and all subsequent anomaly detections are based on this equilibrium baseline envelope.

[0080] After the equilibrium baseline envelope is established, the controlled temperature-pressure active excitation step is executed. First, baseline reset is performed; that is, before executing the temperature-pressure active excitation, the system is allowed to run stably again for 2-5 minutes at the equilibrium baseline operating point, confirming that the steady-state total flow rate, steady-state system pressure drop, steady-state inlet and outlet temperature rise, and steady-state near-far thermal response difference are all within the normal range corresponding to the equilibrium baseline envelope. Simultaneously, both the primary and secondary wetting sensors output dry-state signals. After confirmation, controlled pressure loading is executed: while maintaining a relatively stable total coolant flow rate Q, the overall system pressure is linearly and slowly increased over time by adjusting the back pressure regulating valve opening. The pressure loading rate is controlled to be 5%-10% / min of the rated maximum operating pressure of the dual-port microfluidic liquid cooling assembly, with the target pressure not exceeding 95% of the rated maximum operating pressure. During the controlled pressure loading process, the circulation pump speed is simultaneously fine-tuned to compensate for the flow rate changes caused by the increase in back pressure, ensuring that the fluctuation range of the total coolant flow rate Q relative to the flow rate corresponding to the equilibrium baseline operating point does not exceed ±5%.

[0081] Once the controlled pressure reaches the target pressure and the system pressure stabilizes, controlled thermal loading is performed: the temperature of the circulating coolant entering the dual-port microchannel liquid cooling assembly is increased via the liquid temperature regulation unit, with the heating rate controlled at 2°C / min to 5°C / min, and the target temperature not exceeding 95% of the rated maximum operating temperature of the dual-port microchannel liquid cooling assembly. During controlled thermal loading, the system pressure is kept stable, and the total coolant flow rate Q is maintained within the aforementioned allowable fluctuation range. Due to the differences in thermal expansion coefficients among the capping layer, substrate layer, sealing components, and bonding materials of the dual-port microchannel liquid cooling assembly, the combined effect of increased internal fluid static pressure and increased coolant temperature makes it easier for tiny gaps at leakage-sensitive interfaces to open briefly, thus making condition-dependent microleakage, which is difficult to detect under normal steady-state conditions, detectable.

[0082] After both controlled pressure loading and controlled heat loading reach their target values, a temperature-pressure coupling condition maintenance step is executed. Specifically, the system is maintained at the target pressure and temperature for 5–30 minutes, ensuring that pressure and temperature fluctuations do not exceed ±2% of the target values. During the temperature-pressure coupling condition maintenance period, inlet pressure, outlet pressure, total flow rate, inlet temperature, outlet temperature, near-end area outer wall temperature, far-end area outer wall temperature, primary wetting sensor output signal, and secondary wetting sensor output signal are continuously and in real-time collected to monitor the dynamic changes of each parameter and the triggering sequence of the two-stage wetting signals. This stage provides sufficient pressure and heat exposure time for potential micro-gaps at leak-sensitive interfaces and sufficient time for trace amounts of leaked fluid to migrate along the primary capillary collection channel, transition flow restriction section, and secondary exposure cavity.

[0083] After the temperature-pressure coupling condition holding phase ends, a controlled recovery step is executed. Specifically, the circulating coolant temperature is first reduced at the same rate as the controlled thermal loading. Once the coolant temperature recovers to the temperature corresponding to the equilibrium baseline operating point, the system pressure is then reduced at the same rate as the controlled pressure loading until the system recovers to the operating condition corresponding to the equilibrium baseline operating point. During the controlled recovery process, various fluid parameters, temperature parameters, and the output signals of the primary and secondary wetting sensors are also collected in real time. It should be noted that the microleakage channels may reclose after the temperature and pressure drop, and new leakage behavior will stop. However, the trace amounts of coolant that have already seeped from the leakage-sensitive interface will remain in the primary capillary collection channel, the transition flow restriction section, and the secondary exposure cavity, and continue to migrate or spread. Therefore, the controlled recovery phase is an important stage for extracting the microleakage hysteresis and tailing characteristics.

[0084] After completing the above excitation and recovery steps, a multi-dimensional fault discrimination and classification step is performed. First, based on whether the two-stage wetting signals are triggered, the abnormal state of the tested component is divided into non-leakage anomalies and leakage anomalies. If, throughout the entire controlled pressure loading, controlled heat loading, temperature-pressure coupling condition maintenance, and controlled recovery process, both the primary and secondary wetting sensors consistently output dry signals, then the real-time collected near-far thermal response difference ΔTw, system pressure drop ΔP, and total coolant flow rate Q are compared with the baseline normal range of the corresponding parameters in the equalization baseline envelope. If the near-far thermal response difference ΔTw continuously exceeds the corresponding baseline normal range, the total coolant flow rate Q is lower than the corresponding baseline normal range, and the system pressure drop ΔP is higher than the corresponding baseline normal range, then it is determined to be a local blockage or particulate deposition anomaly; if the near-far thermal response difference ΔTw exceeds the corresponding baseline normal range and is accompanied by irregular fluctuations, while the total coolant flow rate Q and system pressure drop ΔP both show irregular fluctuations, then it is determined to be a system gas entrainment or gas evolution anomaly.

[0085] If either the primary or secondary wetting sensor outputs a wet signal during the diagnostic process, the process enters the leakage anomaly identification procedure. During leakage anomaly identification, the following core characteristics are extracted: the triggering sequence of the primary and secondary wetting sensors, the triggering time interval Δt between the two wetting signals, the operating condition stage corresponding to the first triggering of the two wetting signals, the continuous state of the two wetting signals after controlled recovery, and the corresponding changes in total flow rate Q and system pressure drop ΔP. If any of the following conditions occur, it is determined to be a direct external leakage anomaly: First, the time difference Δt between the output wet signals of the primary and secondary wetting sensors is less than a preset time threshold, preferably 10 seconds; second, the secondary wetting sensor outputs a wet signal before the primary wetting sensor; third, both the primary and secondary wetting sensors output wet signals at the initial stage of controlled pressure loading, and the wetting signal intensity continuously increases with the loading process, while the total coolant flow rate Q continuously and irregularly increases and the system pressure drop ΔP continuously and irregularly decreases. Direct external leakage corresponds to penetrating damage or large-flow leakage. Its characteristic is that the leaking fluid quickly fills the leakage area, so the two exposed locations will be wetted simultaneously in a short period of time.

[0086] If the criteria for determining direct external leakage are not met, a further determination is made as to whether it is a micro-leakage anomaly. Specifically, a micro-leakage is determined to exist in the dual-port microchannel liquid cooling assembly when the following two conditions are met simultaneously: First, the primary wetting sensor outputs a wet signal before the secondary wetting sensor, and there is a distinguishable trigger time interval Δt between the two. Preferably, the time interval is greater than the preset time threshold used for determining direct external leakage anomalies. Second, after the system completes controlled recovery and returns to the operating condition corresponding to the equilibrium baseline operating point, the primary and secondary wetting sensors continue to output wet signals. The above two conditions correspond to the timing characteristics and hysteresis / tailing characteristics of micro-leakage, respectively. The mechanism is as follows: after a small amount of leaking liquid seeps out from the leak-sensitive interface, it is first captured by the primary capillary collection channel set near the leak-sensitive interface, so that the primary wetting sensor outputs a wet signal first; under the flow restriction effect of the transition flow restriction section, the leaking liquid needs to accumulate to a certain extent in the primary capillary collection channel before it can further enter the secondary exposure chamber and trigger the secondary wetting sensor. Therefore, there is a time interval between the two wetting signals; after the system recovers to the equilibrium baseline operating point, although the micro-gap may close again, the leaking liquid that has already seeped out is still retained in the primary capillary collection channel, the transition flow restriction section and the secondary exposure chamber, so that the two wetting sensors continue to output wet signals during the recovery phase and after the recovery is completed.

[0087] In this embodiment, based on the above discrimination logic, the operating states of the dual-port microchannel liquid cooling assembly can be classified into the following categories: The first category is the normal equilibrium state, where all parameters are within the equilibrium baseline envelope, and the primary and secondary wetting sensors output dry signals throughout the process; the second category is non-leakage abnormal states, including flow imbalance abnormalities, blockage abnormalities, system entrainment abnormalities, and system gas evolution abnormalities; the third category is direct external leakage abnormal states; and the fourth category is micro-leakage abnormal states. This classification method can identify faults that exhibit abnormalities at the macroscopic parameter level but are not leaks, and can also identify hidden condition-dependent micro-leakages using the temporal characteristics of the two-stage capillary exposure module and the two-stage wetting signals.

[0088] Example 3: Based on the system provided in Example 1 and the method provided in Example 2, this example provides a computer device that executes the method described in Example 2 or any method that may involve the method described in Example 2. The device includes a memory, a processor, and a transceiver connected in sequence. The memory stores a computer program, the transceiver sends and receives messages, and the processor reads the computer program and executes the method described in Example 1 or any method that may involve the method described in Example 2. Specifically, the memory may include, but is not limited to, random-access memory (RAM), read-only memory (ROM), flash memory, first-in-first-out (FIFO) memory, and / or last-in-first-out (FILO) memory, etc.; the processor may include, but is not limited to, a microprocessor of the STM32F105 series. Furthermore, the computer device may also include, but is not limited to, a power module, a display screen, and other necessary components.

[0089] The working process, working details and technical effects of the aforementioned computer device provided in this embodiment can be found in the method described in Embodiment 2 or any method that may involve the method described in Embodiment 2, and will not be repeated here.

[0090] Example 4: This example provides a computer-readable storage medium that stores instructions that include the method described in Example 2 or any other method that may involve the method described in Example 2. Specifically, the computer-readable storage medium stores instructions that, when executed on a computer, perform the method described in Example 2 or any other method that may involve the method described in Example 2. The computer-readable storage medium refers to a data storage medium, which may include, but is not limited to, floppy disks, optical disks, hard disks, flash memory, USB flash drives, and / or Memory Sticks. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.

[0091] The working process, working details and technical effects of the aforementioned computer-readable storage medium provided in this embodiment can be found in the method described in Embodiment 1 or any method that may be related to Embodiment 1, and will not be repeated here.

[0092] Example 5: This example provides a computer program product containing instructions that, when executed on a computer, cause the computer to perform the method described in Example 2 or any method that may involve the method described in Example 2. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device.

Claims

1. A microleakage diagnostic system for a dual-channel microfluidic assembly, characterized in that, include: The dual-port microfluidic liquid cooling assembly includes, in sequence along the fluid flow direction, a connected liquid inlet, an inlet distribution chamber, a microfluidic heat exchange zone, an outlet manifold, and a liquid outlet; one side of the microfluidic heat exchange zone includes a cooling heat source mounting area. The external circulation condition adjustment module is used to provide circulating coolant to the dual-port microchannel liquid cooling component, and to regulate the flow rate, static pressure and temperature of the circulating coolant entering the dual-port microchannel liquid cooling component; the external circulation condition adjustment module forms a closed circulation loop with the dual-port microchannel liquid cooling component through the fluid pipeline; A multi-parameter sensing module is used to collect fluid parameters of the closed loop, temperature parameters of the dual-port microchannel liquid cooling component, and wetting signals of the leakage liquid in real time. A two-stage capillary exposure module is positioned around the leakage-sensitive interface. The leakage-sensitive interface includes the structural interface where micro-gaps and micro-leakage occur during the processing, packaging, and operation of the dual-port microfluidic liquid cooling assembly. Along the direction of leakage fluid migration, the two-stage capillary exposure module sequentially includes a primary capillary collection channel, a transition flow-limiting section, and a secondary exposure cavity located near the outer edge of the leakage-sensitive interface. The flow cross-sectional area of ​​the transition flow-limiting section is smaller than the flow cross-sectional area of ​​the primary capillary collection channel and the flow cross-sectional area of ​​the secondary exposure cavity. A primary wetting sensor is installed in the primary capillary collection channel, and a secondary wetting sensor is installed in the secondary exposure cavity. The data processing and control module is used to realize operating condition control, data acquisition and processing, equalization baseline establishment, and fault identification and classification; the data processing and control module communicates with the multi-parameter sensing module and the external circulation operating condition adjustment module.

2. The microleakage diagnostic system for a dual-channel microfluidic assembly according to claim 1, characterized in that, The multi-parameter sensing module includes: a fluid parameter sensing unit, a temperature sensing unit, and a wetting sensing unit; the wetting sensing unit includes: a primary wetting sensor and a secondary wetting sensor; Along the flow direction of the circulating coolant, the external circulation condition adjustment module sequentially includes: a reservoir, a circulation pump, a coolant temperature control unit, a filter, and a back pressure regulating valve, and also includes a bypass vent branch connected in parallel between the output of the circulation pump and the reservoir; wherein: The circulating pump is a variable frequency speed control pump; the flow rate adjustment range of the circulating pump covers the rated operating flow rate range of the dual-port microchannel liquid cooling assembly. The liquid temperature control unit is located between the circulating pump and the liquid inlet of the dual-port microchannel liquid cooling assembly; the temperature control range of the liquid temperature control unit covers the rated operating temperature range of the dual-port microchannel liquid cooling assembly. The back pressure regulating valve is used to regulate the flow rate and static pressure of the circulating coolant entering the dual-port microchannel liquid cooling component; the back pressure regulating valve is located downstream of the liquid outlet of the dual-port microchannel liquid cooling component. The bypass exhaust branch is equipped with an exhaust control valve.

3. The microleakage diagnostic system for a dual-channel microfluidic assembly according to claim 2, characterized in that: The fluid parameter sensing unit includes: an inlet pressure sensor, an outlet pressure sensor, and a total flow sensor; the inlet pressure sensor is installed at the liquid inlet of the dual-port microchannel liquid cooling assembly, the outlet pressure sensor is installed at the liquid outlet of the dual-port microchannel liquid cooling assembly, and the total flow sensor is installed upstream of the liquid inlet of the dual-port microchannel liquid cooling assembly. The temperature sensing unit includes: an inlet temperature sensor, an outlet temperature sensor, a near-end region outer wall temperature sensor, and a far-end region outer wall temperature sensor. The inlet temperature sensor is installed at the liquid inlet of the dual-port microchannel liquid cooling assembly, the outlet temperature sensor is installed at the liquid outlet of the dual-port microchannel liquid cooling assembly, the near-end region outer wall temperature sensor is installed on the side of the microchannel heat exchange zone near the inlet distribution chamber, and the far-end region outer wall temperature sensor is installed on the side of the microchannel heat exchange zone near the outlet manifold. The near-end region outer wall temperature sensor and the far-end region outer wall temperature sensor are on the same measured plane and are installed in the same way.

4. The microleakage diagnostic system for a dual-channel microfluidic assembly according to claim 1, characterized in that, The primary capillary collection channel is a microgroove structure with capillary adsorption capacity, and it is located close to the leakage-sensitive interface. The transition flow-limiting section is a narrow slit structure, a microporous structure, or a capillary bundle structure. The size of the transition flow-limiting section is smaller than that of the primary capillary collection channel. The volume of the secondary exposure cavity is larger than that of the primary capillary collection channel. The internal flow resistance of the secondary exposure cavity is smaller than that of the transition flow-limiting section.

5. The microleakage diagnostic system for a dual-channel microfluidic assembly according to claim 4, characterized in that, The distance between the primary capillary collection trench and the leakage-sensitive interface shall not exceed 2 mm. The cross-sectional shape of the primary capillary collection trench shall be rectangular, trapezoidal, or V-shaped. The top opening width and depth of the primary capillary collection trench shall be 50 μm-200 μm. The inner wall of the primary capillary collection channel is hydrophilically modified, and the contact angle between the inner wall of the primary capillary collection channel and the circulating coolant is less than 30°.

6. The microleakage diagnostic system for a dual-channel microfluidic assembly according to claim 1, characterized in that, Both the primary and secondary wetting sensors are interdigitated electrode capacitive wetting sensors; the sensitive element of the primary wetting sensor is attached to or integrated into the inner wall or bottom of the primary capillary collection channel, while the sensitive element of the secondary wetting sensor is arranged at the bottom of the secondary exposure cavity.

7. The microleakage diagnostic system for a dual-channel microfluidic assembly according to claim 1, characterized in that, The data processing and control module includes: a working condition control module, which sends liquid filling control commands, exhaust control commands, working condition adjustment control commands, and temperature and pressure window excitation control commands to the external circulation working condition adjustment module; The data processing module is used to collect measurement data from the multi-parameter sensing module in real time, filter and reduce noise in the strategy data, and calculate the system pressure drop, inlet and outlet temperature rise and near-far thermal response difference. The baseline establishment module is used to select the equilibrium baseline operating point based on the difference in near-far thermal response and to establish the equilibrium baseline envelope. The fault diagnosis module is used to determine the system's operating status by combining the operating condition excitation timing, the triggering sequence and time interval of the wetting signal, and the recovery characteristics of the parameters. It classifies and identifies normal status, flow imbalance, blockage, direct external leakage, and breathing leakage and outputs diagnostic results.

8. A method for diagnosing microleakage in a dual-channel microfluidic assembly, characterized in that, Based on the dual-port microchannel liquid cooling component microleakage diagnostic system according to any one of claims 1-7, the following steps are performed: Multiple candidate operating points were set within the rated operating range of the dual-port microchannel liquid cooling assembly. The total flow rate, system pressure drop, near-end region outer wall temperature, far-end region outer wall temperature, and wetting status of the two-stage wetting sensors were collected for each candidate operating point. The near-end and far-end thermal response difference was calculated based on the near-end and far-end outer wall temperatures. The candidate operating points were sorted from small to large according to the near-end and far-end thermal response difference. Combining the total flow rate, system pressure drop, and wetting status of the two-stage wetting sensors, the balanced baseline operating point was selected from the sorted candidate operating points. Under the operating conditions corresponding to the equilibrium baseline operating point, the steady-state total flow, steady-state system pressure drop, and steady-state near-far thermal response difference are collected to establish the equilibrium baseline envelope. At the balanced baseline operating point, controlled pressure loading, controlled thermal loading, and controlled recovery are executed sequentially, and the total flow rate, system pressure drop, near-far thermal response difference, and wetting status of the two wetting sensors are collected in real time. When neither of the two wetting sensors outputs a wetting signal, the total flow rate, system pressure drop, and near-far thermal response difference collected in real time are compared with the equalization baseline envelope. When at least one of them exceeds the normal range of the corresponding baseline in the equalization baseline envelope, a non-leakage anomaly is determined. When the two-stage wetting sensors output wetting signals, the triggering sequence, triggering time interval, and wetting signal continuity status after the system recovers to the equilibrium baseline operating point are extracted. If the first-stage wetting sensor outputs a wetting signal before the second-stage wetting sensor, there is a triggering time interval between them, and the two-stage wetting sensors continue to output wetting signals after the system recovers to the equilibrium baseline operating point, it is determined that there is micro-leakage in the dual-port microfluidic liquid cooling component.

9. The method for diagnosing microleakage in a dual-channel microfluidic assembly according to claim 8, characterized in that, The temperature sensor on the outer wall of the proximal region is installed on the side of the microfluidic heat exchange zone near the inlet distribution cavity, and the temperature sensor on the outer wall of the distal region is installed on the side of the microfluidic heat exchange zone near the outlet manifold cavity. The near-far thermal response difference is the absolute value of the difference between the outer wall temperature of the near region and the outer wall temperature of the far region. The balanced baseline operating point is selected from the ranked candidate operating points, including: starting from the candidate operating point at the top of the ranking, the operating point is checked in sequence. When the total flow rate and system pressure drop are within the rated operating range of the dual-port microchannel liquid cooling component and both the primary and secondary wetting sensors are kept dry, the current candidate operating point is determined as the balanced baseline operating point.

10. The method for diagnosing microleakage in a dual-channel microfluidic assembly according to claim 8, characterized in that, Establishing the equilibrium baseline envelope includes: maintaining stable system operation under the operating conditions corresponding to the equilibrium baseline operating point; collecting steady-state total flow, steady-state system pressure drop, steady-state near-far thermal response difference, and inlet / outlet temperature rise; calculating the steady-state mean and standard deviation of the steady-state total flow, steady-state system pressure drop, steady-state near-far thermal response difference, and inlet / outlet temperature rise respectively; determining the baseline normal range of each parameter by subtracting three times the standard deviation from the steady-state mean to adding three times the standard deviation, and forming the equilibrium baseline envelope based on the baseline normal range of each parameter.

11. The method for diagnosing microleakage in a dual-channel microfluidic assembly according to claim 8, characterized in that, Controlled pressure loading includes: adjusting the opening of the back pressure regulating valve and simultaneously adjusting the speed of the circulating pump when the total flow fluctuation is within a preset range; Controlled thermal loading includes adjusting the liquid temperature control unit after the controlled pressure loading reaches the target pressure to increase the temperature of the circulating coolant entering the dual-port microchannel liquid cooling assembly; Controlled recovery includes: first restoring the circulating coolant temperature to the temperature corresponding to the equilibrium baseline operating point, and then restoring the system pressure to the pressure corresponding to the equilibrium baseline operating point.

12. The method for diagnosing microleakage in a dual-channel microfluidic assembly according to claim 8, characterized in that, If the time difference between the output of the primary and secondary wetting sensors is less than a preset time threshold, or if the secondary wetting sensor outputs a wetting signal before the primary wetting sensor, or if the primary and secondary wetting sensors output a wetting signal immediately after the controlled pressure loading stage begins and the intensity of the wetting signal continues to increase, while the total flow rate increases irregularly and the system pressure drop decreases irregularly, then it is determined that there is a direct external leakage abnormality in the dual-port microfluidic liquid cooling component.

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