Excellent Temperature Uniformity Research Articles

A Y-Type Air-Cooled Battery Thermal Management System with a Short Airflow Path for Temperature Uniformity

A Y-type air-cooled structure has been proposed to improve the heat dissipation efficiency and temperature uniformity of battery thermal management systems (BTMSs) by reducing the flow path of air. By combining computational fluid dynamics (CFD) methods, the influence of the depths of the distribution and convergence plenums on the airflow velocity through battery cells was analyzed to improve heat dissipation efficiency. Adjusting the width of the first and ninth cooling channels can change the air velocity of these two channels, thereby improving the temperature uniformity of the BTMS. Further discussion was conducted regarding the influences of inlet and outlet depths. When the inlet width and outlet width were 20 mm, the maximum temperature and maximum temperature difference of the Y-type BTMS were 39.84 °C and 0.066 °C at a discharge rate of 2.5 °C, respectively; these temperatures were 1.537 °C (3.68%) and 0.059 °C (47.2%) lower than those of the T-type model. Meanwhile, the energy consumption of the sample also decreased by 13.1%. The results indicate that the heat dissipation performance of the proposed Y-type BTMS was improved, achieving excellent temperature uniformity, and the energy consumption was also reduced.

Numerical study on a new manifold ring-shaped microchannel structure for circular heat source with excellent temperature uniformity

The manifold microchannel heat sink shows great potential for cooling high-heat-flux electronic equipment owing to its exceptional thermal and flow performance. A new manifold ring-shaped channel design is introduced to improve the temperature uniformity for circular heat sources. A comparative analysis of the manifold straight channel, radial expansion channel and manifold ring-shaped channel designs is conducted based on the same heating area under equal mass flow conditions by numerical investigation using single-phase de-ionized water. The findings indicate that the newly proposed manifold ring-shaped channel design exhibits a lower maximum temperature, a lower average temperature, a better temperature uniformity and a smaller pressure drop in comparison to the straight channel and radial channel designs. Specifically, at a mass flow rate of 2.5 g/s, the ring-shaped channel design demonstrates a 71.4 % and 45.4 % reduction in the temperature difference between the maximum temperature and the minimum temperature of the heating surface, and the coefficient of performance is enhanced by 458.2 % and 169.7 % when compared to the straight channel and radial channel designs, respectively. Additionally, three improved designs based on the original manifold ring-shaped channel design are proposed to further enhance fluid flow distribution in the ring-shaped channel design. The results reveal that all three manifold ring-shaped channel optimizations further lower the maximum temperature, the average temperature and the temperature difference. Notably, the improved case3 exhibits the best thermal and hydraulic performances among all structures. When compared to straight channel and radial channel designs, the improved case3 demonstrates an 86.9 % and 75.0 % reduction in the temperature difference, and an increase of 201.2 % and 523.4 % in coefficient of performance under the equal mass flow comparison basis. A heat flux of 1200 W/cm2 can be dissipated at 6 g/s when the maximum temperature rise is kept below 60 K, with a pressure drop of 38 kPa.

Design and application of high-precision calibration blackbody for space optical remote sensing sensor

Radiation calibration is a crucial step in producing high-quality images for spaceborne infrared cameras. Blackbody radiation sources, as the standard equipment for infrared thermometers, play an increasingly important role in radiation calibration. But as the camera aperture increases, blackbody faces challenges such as poor temperature uniformity, slow heating and cooling rates, large mass, and large volume. This article proposes a design scheme for spaceborne calibration blackbody based on a combination of rope pull fixation and limit block positioning. The temperature uniformity, temperature stability, temperature rise and fall rate, thermal stress characteristics, and anti-emission vibration characteristics of the blackbody under this scheme are analyzed and optimized in detail. The analysis results show that the conduction thermal resistance between the blackbody and the environment is nearly two orders of magnitude higher than that of the conventional scheme. The blackbody has excellent temperature uniformity, temperature stability, wide calibration temperature range, light weight, small volume, and fast temperature rise and fall speed. The blackbody scheme with a thickness of only 1.5 mm was implemented and applied on orbit.

Thermohydraulic and thermal fatigue characteristics of W/Cu flat-type microchannel mock-up for CFETR divertor

The divertor of the China Fusion Engineering Test Reactor (CFETR) requires a more efficient heat dissipation structure due to the high demand of heat flux dissipation of up to 20 MW/m2. Microchannel cooling technology excels in thermal management because of large heat transfer area to volume ratio and capability to achieve uniform temperature distribution. However, the heat transfer and thermal fatigue characteristics of W/Cu flat type mock-up with microchannel cooling structures at a heat flux of 20 MW/m2 remains elusive. In this work, we analyzed the thermohydraulic (numerically) and thermal fatigue (experimentally) characteristics of W/Cu flat-type microchannel mock-up. The numerical results show that the thermal loaded area (W) of the microchannel mock-up possesses excellent temperature uniformity and heat transfer performance (the W surface temperature is only ∼685 °C even at a low volumetric flow rate V̇ = 5 L/min). We also compared the heat dissipation efficiency with the hypervapotron cooling channels, and found that the maximum temperature of the W surface and channel wall of the microchannel mock-up are reduced by 18.9 % and 46.7 %, respectively. The thermal stress analysis indicates that the maximum equivalent stress is concentrated in the middle region of the W surface at 15 s, with a value of 357.8 MPa that is below the maximum allowable stress of W material (425 MPa at 650 °C). The as-manufactured W/Cu flat-type microchannel mock-up successfully withstood a thermal fatigue test consisting of 1000 cycles at 20 MW/m2 steady state heat load at V̇ = 30 L/min and Tin = 25 °C. The maximum temperature of W is only 616.2 °C during the test, and some microcracks are detected on the W surface after the test; these microcracks are perpendicular to the heat loading surface, which have negligible influence to the heat transfer of the entire mock-up. This study reveals that the W/Cu flat-type microchannel mock-up is promising in dissipating ultra-high heat flux (steady-state 20 MW/m2) on the divertor target, which might provide valuable insights for the engineering design of the CFETR divertor.

Multi-objective optimization of a combined heat sink with triangular protrusion and corrugated surface impinged by a nanofluid slit-confined jet

Improving temperature uniformity and heat transfer capacity is crucial for the application of a jet-impingement heat sink in dissipating heat from high-power electronic devices. Therefore, a combined heat sink with a triangular protrusion in the stagnation zone, a corrugated surface in the wall-jet zone, and an oblique angle of the upper plate impinged by a nanofluid jet is proposed. A two-dimensional model is established, using Al2O3-H2O nanofluid as coolant. The effects of the structural parameters of the heat sink, the volume fraction of the nanofluid on the temperature uniformity of the heat sink and the jet-impingement heat transfer were studied numerically. Meanwhile, the structure of the heat sink is optimized by the NSGA-II genetic algorithm. The results indicate that the three structures can enhance both the temperature uniformity and the heat-transfer capacity. Using nanofluids with a 3%volume fraction and a Reynolds number of 8,000, the average Nusselt number of the optimal structure is 26 % greater than that of a jet impingement flat heat sink, the temperature standard deviation is 67 % less, and the friction coefficient and thermal-hydraulic performance factor are greater by 55 % and 9 %, respectively. Meanwhile, the optimized structure exhibits excellent heat dissipation and temperature uniformity at higher heat flux. The allowable maximum heat flux reaches 341 W/cm2 when the junction temperature of the hot spot does not exceed 348 K, and the temperature standard deviation is 2.926, which are increase by 83 % and decrease by 36 % compared with that of jet-impingement plate heat sink, respectively.

Development of a pipeless, cascade phase change power battery thermal management system

To solve the problems of pipe weight and phase change material (PCM) utilization in the PCM coupled liquid cooling system, a novel pipeless cascade shape-stabilized phase change material coupled phase change emulsion (PCE) cascaded with the shape-stabilized PCM BTMs was proposed. Firstly, a pipeless shape-stabilized PCM channel with high thermal conductivity was prepared. Compared with pure PCM, its thermal conductivity was increased by about 45 times, and it had excellent leakage prevention ability. Then the cooling performance of the shape-stabilized PCM channel BTMs was compared to the metal channel BTMs, and the cooling performance of the PCE/shape-stabilized PCM channel BTMs was compared to the performance of the water/shape-stabilized PCM channel BTMs. It turns out that the shape-stabilized PCM channel coupled PCE BTMs have both good temperature control performance and excellent temperature uniformity. And the thermal management performance of pipeless cascaded shape-stabilized PCM and the cascade between shape-stabilized PCM and PCE in BTMs was studied. Compared with BTMs without cascade phase change, the maximum temperature and maximum temperature difference are reduced by 1.7 °C and 0.5 °C, respectively. What's more, compared to the PCE cascaded with the shape-stabilized PCM, the cascaded shape-stabilized PCM channel has a greater influence on the performance of the BTMs. Finally, compared with other existing BTMs, this work has strong competitiveness in reducing the maximum temperature and the maximum temperature difference of the battery module.

Performance Study of Battery Thermal Management System With a Bionic Cooling Plate Based on Leaf Vein Channels of Plantain

Abstract The microchannel cooling plate is a vital component in an efficient battery thermal management system (BTMS) that has been widely used to design battery modules for electric vehicles. In this study, regarding the leaf vein structure of plantain, a novel bionic cooling plate similar to the plantain leaf vein channels was proposed. A three-dimensional mathematical model of BTMS including the bionic cooling plate was established. The effects of the structure type; the reducing angle of the main inlet channel; the number, angle, and width of branch channels; and the inlet mass flowrate of the coolant on the thermal performance of the BTMS were investigated. The results indicated that the cooling plate of single-inlet and double-outlet channels with leaf veins exhibited excellent comprehensive performance. The increase of the reducing angle of the main inlet channel decreased the pressure drop by up to 43.55% but could not improve the temperature uniformity of batteries; the maximum temperature difference of batteries increased by 0.11 °C. A larger number of branch channels and a smaller angle of branch channels can improve the cooling performance of BTMS, while the increase in the width of branch channels significantly decreases the pressure drop. At a coolant inlet mass flowrate of 1 g/s, the BTMS can control the maximum temperature and maximum temperature difference of the batteries at a 3C discharge rate to 31.75 °C and 4.95 °C, respectively, and exhibited excellent temperature uniformity at low pressure drop (669 Pa).

Enhanced heat transfer in a latent heat thermal energy storage unit using a longitudinal fin with different structural parameters

The latent heat thermal energy storage (LHTES) unit can be used to resolve the imbalance between energy supply and demand. To boost heat storage efficiency, a model with longitudinal fins was developed to accelerate the melting process. Based on the finite volume method (FVM), the effect of fin angle and number on melting performance was evaluated. Further, the response surface methodology (RSM) was applied to optimize the longitudinal fin by maximizing its melting rate. Results demonstrate same heat transfer capacity at the fin angles θ and θ1(θ1=90−θ). The complete melting time at a θ values of 0°was reduced by 46.66%, compared with a θ value of 45°. The optimized case (θ = 0°, N =16 fins) reduced the total melting time by 62.59%. The melting rate of the upper region of the LHTES unit was higher than that of the lower region in all cases. Further, the study quantified the temperature uniformity of the system using mathematical methods, which showed that the integrated mean value of temperature uniformity at a θ value of 0° was the smallest (12.51°C), suggesting excellent temperature uniformity at a rotation angle of 0°.

Experimental study of a passive thermal management system using vapor chamber for proton exchange membrane fuel cell stack

To mitigate the parasitic power consumption caused by conventional air and water cooling, this study proposes a novel passive cooling scheme that integrates vapor chambers into proton exchange membrane fuel cell stack for thermal management. A 1.32 mm thick vapor chamber is designed and fabricated, and its heat transfer performance is verified through tests conducted at different powers using a heating pad. After confirming that vapor chambers can meet the heat dissipation requirements, the output characteristics of the stack coupled with vapor chambers, are experimentally evaluated during both fast start-up and steady-state operation. Results demonstrate that the vapor chamber efficiently operates at a heat flux density of only 0.052 W/cm2 at evaporation section, while maintaining a maximum in-plane temperature difference of 2.6 °C at 48 W. During fast start-up loading of the stack from 0 A to 40 A, the vapor chamber exhibits rapid thermal response and excellent temperature uniformity, preventing stack performance degradation due to improper operating temperatures. Compared to a general air-cooled stack, the stack coupled with vapor chambers exhibits a significant 21.7% improvement in stack voltage. These results systematically demonstrate the feasibility of vapor chambers for the thermal management of air-cooled proton exchange membrane fuel cell stacks.

Heat transfer enhancement in cold plates with wavy channels via free-shape modeling and optimization

The objective of this study is to improve heat transfer performance of cold plates with wavy channels typically used in Battery Thermal Management Systems (BTMSs). The means of enhanced design flexibility based on parametric modeling allows for the free construction of wavy geometry in terms of amplitudes, wavelengths, waveforms, and cross-sections. The fixed dimensions are “liberated” into these four degrees of freedom, which helps to find the optimized wavy structures with the superior cooling performance. Based on the proposed free-shape modeling framework, the Horizontal Wavy Channel (HWC) and Radial Wavy Channel (RWC) are constructed, and these single channels can be considered as the basic structure of cold plates. One of the most popular evolutionary algorithms, NSGA−II, is utilized to optimize these two types of channels. The average temperature (overall thermal performance) and root mean square temperature (temperature uniformity) of top and bottom surfaces of cold plates are specified as the objective functions. In addition, to better verify the validity of the proposed method, empirical-based uniform HWC (UHWC) and RWC (URWC) are given as further comparisons. Based on the obtained Pareto front and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method, when the weight coefficients of the two thermal performance indicators are set to 0.5:0.5, the best compromised solutions are obtained: VHWC−22 for HWC and VRWC−30 for RWC. The results further show that the ranking of excellent overall thermal performance is VHWC−22 > URWC >≈ VRWC−30 > UHWC, while the ranking of excellent temperature uniformity is VRWC−30 > VHWC−22 > URWC > UHWC. Obviously, the variable wavy channels are generally superior the uniform wavy channels in terms of thermal performance. This work provides a guideline for the design of wave structures that can be used not only in cold plates but also in heat sink with fins, heat exchangers, and other components with wave structures.

Advanced In Situ TEM Microchip with Excellent Temperature Uniformity and High Spatial Resolution.

Transmission electron microscopy (TEM) is a highly effective method for scientific research, providing comprehensive analysis and characterization. However, traditional TEM is limited to observing static material structures at room temperature within a high-vacuum environment. To address this limitation, a microchip was developed for in situ TEM characterization, enabling the real-time study of material structure evolution and chemical process mechanisms. This microchip, based on microelectromechanical System (MEMS) technology, is capable of introducing multi-physics stimulation and can be used in conjunction with TEM to investigate the dynamic changes of matter in gas and high-temperature environments. The microchip design ensures a high-temperature uniformity in the sample observation area, and a system of tests was established to verify its performance. Results show that the temperature uniformity of 10 real-time observation windows with a total area of up to 1130 μm2 exceeded 95%, and the spatial resolution reached the lattice level, even in a flowing atmosphere of 1 bar.

Research on Calibration Sources for a 35–40 GHz Millimeter-Wave Solar Radio Observation System

The microwave spectra in the optically thin regime provides unique information about the solar corona magnetic field; thus, a millimetre-wave solar radio observation system (35-40 GHz) in the Chashan Observatory is newly established to obtain relevant data. Herein, we design and develop a blackbody calibration source employing a metal cone array and absorbing patch to calibrate the system and obtain accurate solar observation data for analysis and decision-making. The reflectivity of the calibration source is simulated and measured to characterize its emissivity. The reflectivity is obtained by the finite-integration (FIT) method under various fitting conditions, i.e., the thickness of the absorbent patches and aspect ratios of the cone. The temperature gradient of cones is determined by the finite-element method (FEM). A 5×5 array microwave blackbody was developed based on a cone with a low scattering coefficient and excellent temperature uniformity. To reduce the influence of spurious signals, the time-domain gate technique is used to test the reflectivity of the target. The results demonstrate that the emissivity of the blackbody is higher than 0.9995 in the 35-40 GHz band. The temperature difference between the cone top and the cone bottom is 0.20 °C.

Fast self-preheating system and energy conversion model for lithium-ion batteries under low-temperature conditions

Low temperature is one of the major drawbacks of electric cars in high latitudes. This problem can be addressed using a battery self-preheating system. The existing self-heating systems have problems, such as slow heating rate, complex control system, single thermal management function and poor safety. Herein, we propose a conductive phase change material (cPCM)-based self-preheating system that generates heat simultaneously using the internal resistance of cells and external resistance of the cPCM. This self-preheating system shows a high heating rate of 17.14 °C/min and excellent temperature uniformity (temperature difference of 3.58 °C). The system can preheat the battery safely in the capacity range of 20%–100%. When the battery pack is set in −20 °C, the effective electric energy can be increased by 550% after preheating. An energy conversion model is also built to measure the relationship between the energy improvement of battery and the energy consumption by preheating. This energy conversion model can help the system to make the optimal preheating strategy and obtain the maximum discharge energy. Nevertheless, based on the outcome of this study, this self-preheating strategy can effectively solve the problem of battery in low temperatures and maximize the effective electric energy of the battery.

A step-wise numerical thermal control method for advanced composite curing process using digital image based programming

Accurate temperature control is required in advanced heat treatment processes such as composite curing. The crux is how to determine the appropriate heat sources which would result in the required temperature distribution during part heating process. This paper presents a new thermal control method using digital image based programming, which efficiently and accurately estimates required heat sources and controls temperature distribution in a step-wise numerical manner. The method was validated in both simulation and real heating tests for microwave curing of composites, showing excellent temperature uniformity and consistency with given target temperature profiles, compared with existing technologies.

Thermal performance of a lithium-ion battery thermal management system with vapor chamber and minichannel cold plate

An effective battery thermal management system is essential to maintain the operating temperature of lithium-ion batteries for electric vehicles in the optimum range and excellent temperature uniformity. In this work, a novel battery thermal management system based on a vapor chamber and minichannel cold plate is proposed to cool and preheat the battery module. A transient numerical simulation is developed and verified by experiments. The thermal characteristics of three battery thermal management systems are analyzed: natural convection cooling, minichannel cold plate cooling, and mixed minichannel cold plate and vapor chamber cooling. Subsequently, the effects of the discharge rate (1C, 2C, 3C), the arrangement and width of the minichannel cold plate, the coolant inlet velocity and coolant temperature on the cooling performance of the systems are investigated. The research results reveal that compared with natural convection cooling and minichannel cold plate cooling, mixed minichannel cold plate and vapor chamber cooling method exhibits lower maximum temperature and more uniform temperature distribution. When the batteries are discharged at 2C and the coolant temperature is 25 °C, the maximum temperature and temperature difference of the batteries can be maintained at 29.6 °C and 3.5 °C respectively. In addition, the preheating performance of the battery module at subzero temperature is also discussed. The results indicate that the proposed battery thermal management system with vapor chamber and minichannel cold plate also exhibits rapid heating capacity and excellent temperature uniformity.

Experimental study on heat transfer performance of high temperature heat pipe with large length-diameter ratio for heat utilization of concentrated solar energy

• A conceptual model of dish concentrated solar receiver based on finned high temperature heat pipe (HTHP) is designed. • A batch of HTHPs with large length to diameter ratio and excellent performance were prepared. • The frozen start-up, steady heat transfer and consecutive operation performance of the HTHP with large length to diameter ratio are studied theoretically and experimentally. • A finned HTHP with excellent performance is prepared, and its enhanced heat transfer capacity was verified by experiment. Solar receiver, as the core device of the dish concentrated solar thermal power generation system, is becoming a research focus and has attracted much attention. High temperature heat pipe, which works by following the principle of vapor–liquid circulation, has the ability to flatten the temperature of the hot spot, and maintain excellent heat transfer performance with the illumination of concentrated facula with inhomogeneous ultra-high energy flux density; Through the structural design, the compressed air flows outside of the high temperature heat pipe, and thus, compared with flowing in the pipe, the heat transfer coefficient is increased and the flow resistance is reduced. In view of the above advantages, we designed a dish concentrated solar receiver with finned high temperature heat pipe as the core heat transfer device, prepared a high temperature heat pipe with a large length-diameter ratio, and conducted a quantitative performance study comprehensively and systematically. The present study verified the safety and stability of the high temperature heat pipe with the illumination of concentrated facula with inhomogeneous ultra-high energy flux density, theoretically analyzed the process of frozen start-up and heat transfer limits of high temperature heat pipe, explored the reasonable frozen start-up mode, carried out the parameter optimization and consecutive long-time operation stability test, and quantitatively verified the enhanced heat transfer capacity of finned high temperature heat pipe through the experiment. The results show that the HTHP prepared by the same process can operate safely and stably with the illumination of concentrated facula at the average energy flux density of 2.3 × 10 6 W/m 2 , and maintain a high temperature above 700 ℃ as well as excellent temperature uniformity, which fully verifies the feasibility and superiority of HTHP as the core heat transfer device of the dish concentrated solar receiver. In addition, these results can provide quantitative experimental data and theoretical reference for the design and development of the dish concentrated solar receiver.

Thermal performance of a medium temperature cesium heat pipe at different inclination angles

The cesium heat pipe has great potential in the medium temperature heat transfer fields for its large heat transfer capacity and high isothermality. To present the thermal performance of a cesium heat pipe, especially under different inclination angles, a cesium heat pipe is fabricated and tested in this work. As a result, the applicability of the theoretical calculation of the transition temperature to the cesium heat pipe is verified by the maximum temperature variation rate. Then, the frozen startup process with a sonic limit is described in detail which obeys the same rule as other alkali metal heat pipes. Furthermore, the effects of the heating powers (317.2 W ∼ 1416.2 W) and the inclination angles (0°, 30°, 60°, 68°, and 80°) on the thermal performance of the cesium heat pipe are experimentally analyzed. To precisely evaluate the temperature uniformity, the standard deviation of axial temperature in the condenser is calculated. The results indicate that the cesium heat pipe shows excellent temperature uniformity at 68°. The end of the condenser presents a non-negligible temperature gradient at 80° which can be reduced by adding a heat shield in the adiabatic section.

Visualization and Heat Transfer Performance of Mini-Grooved Flat Heat Pipe Filled with Different Working Fluids.

Mini-grooved flat heat pipe (MGFHP) possesses the advantages of high compactness, no mechanical component, super thermal conductivity, and excellent temperature uniformity, which can meet the demand for electronic devices efficiently cooling. In this research, visual and heat transfer experiments were performed to investigate the flow and thermal characteristics inside the MGFHP. Fluid flow and distribution are observed to be quite different in the MGFHP containing different working fluids, which is affected by the physical properties of working fluid, the surface state of the grooved wick, and limited working space. Additionally, the input heat, working fluid type, filling ratio, and wettability obviously affect the thermal conductivity and temperature uniformity of the MGFHP. The deionized water-filled MGFHP possesses lower thermal resistance and higher heat transfer capacity than anhydrous ethanol or hexane filled MGFHP, especially for the copper oxide MGFHP filled with deionized water with a filling ratio of 1.0. Thermal resistance, maximum temperature, and temperature nonuniformity at the condensation section of deionized water-filled copper oxide MGFHP are lower than those of the original copper MGFHP by 31.1%, 3.7 °C, and 0.11 °C for the anhydrous ethanol filled MGFHP and 34.4%, 3.1 °C, and 0.13 °C for the hexane filled MGFHP, respectively.

Visualization research on influencing factors of flat heat pipes

Flat heat pipes can effectively spread a concentrated high power heat source in a small region into a larger heat dissipation area, which is widely used in the thermal management of electronic devices. In this paper, two different sintered copper powder wick structures are designed to study the effect of porous column height on the heat transfer performance. The results show that the best performance is achieved at the 30% filling ratio under the 15 ℃ cooling water with all the porous columns contacting with the condenser. The heat power is 312.7 W and the thermal resistance is 0.192 ℃/W. As the cooling water temperature increases, the evaporation rate increases, resulting in a decrease in the thermal resistance. But the decrease in temperature difference causes the decline in heat dissipation power. Through the visual observation, it is found that the porous column contacting with the condenser can not only play the role of support and liquid reflow pathway, but also serve as an effective evaporation area to improve the heat transfer performance. While the low porous column cannot transport the condensed liquid and is completely immersed by the liquid under the high filling ratio, which is difficult to promote evaporation rate. In order to improve the performance at air cooling situation, an integrated heat pipe combined the flat heat pipe and fin tubes is designed, which can achieve a heat power of 259.8 W and present excellent temperature uniformity. This research provides the guidelines to optimize the heat transfer performance of porous column wick structures.

Two-stage multichannel liquid–metal cooling system for thermal management of high-heat-flux-density chip array

A two-stage multichannel liquid–metal cooling system for a high-heat-flux-density chip array is investigated in this study. This system exhibits high cooling performance, low cost, excellent temperature uniformity, and high reliability. The first stage, which comprises a multichannel liquid metal convection subsystem, is implemented in the high-heat-flux-density chip area to achieve high cooling performance. The second stage, which comprises a water convection subsystem, is utilized in the low-heat-flux-density area to effectively reduce the system cost. Because the liquid–metal loops are equipped with independent electromagnetic pumps for each chip, the chip temperature can be conveniently adjusted, thereby guaranteeing good temperature uniformity. The experimental results show that the proposed liquid–metal cooling system can accommodate a heat flux of 50–200 W/cm2 with a convective heat transfer coefficient exceeding 20 000 W/(m2·K). Moreover, the flow of liquid metal can be continuously adjusted by varying the input current of the electromagnetic pump to ensure a chip array temperature uniformity of approximately 1 °C. The proposed liquid–metal cooling system can serve as a high-performance solution for the thermal management of high-heat-flux-density chip arrays in data centers.