To address the persistent challenges of temperature drift interference, insufficient sensitivity in the low-pressure region, and high implementation cost in existing airflow sensing technologies for heat dissipation systems, the work aims to propose a novel integrated air inflow monitoring sensor based on carbon nanotube (CNT) functional materials and a dual-mode perception architecture. The sensor monolithically integrates a micro-pressure sensing unit and a temperature sensing unit on a single substrate, enabling simultaneous monitoring of airflow-induced pressure variations and environmental temperature. A key structural innovation lies in the introduction of a stress-concentrating boss within the pressure unit, which amplifies localized strain and significantly enhances piezoresistive responsivity under weak airflow excitation. Meanwhile, the temperature sensing unit employs a voltage-divider-based measurement circuit to realize real-time and accurate acquisition of ambient temperature, which provides a reference for correcting temperature-related errors in pressure signals, and effectively suppresses the effect of thermo-mechanical cross-interference on measurement accuracy.
A finite element analysis (FEA) model was established to investigate the structural mechanics, resistance evolution, and sensing characteristics of the proposed device. Special attention was given to the effect of the boss height of the sensitive layer and the major axis size of the ellipsoid on the sensitivity response characteristics of the sensor. Multiple structural configurations with different boss heights and different ellipsoid major axis sizes were comparatively analyzed. Simulation results verified that all structures exhibited clear and monotonic resistance-pressure relationships within 0-100 kPa, confirming the feasibility of the sensing mechanism and low-pressure sensing. More important, notable performance differentiation was observed in the low-pressure working region. The sensitive layer with a 300 μm boss height and a microstructure with a smaller major axis size exhibited the most excellent low-pressure region performance, with the most significant resistance change and the highest initial sensitivity. Its sensitivity curve demonstrated an evident "rise-peak-decline" evolution, reaching a pronounced maximum near approximately 16 kPa, indicating its superior suitability for detecting subtle airflow disturbances and early-stage airflow degradation. In comparison, increasing boss height reduced strain localization, weakened the electrical response amplitude, and shifted the optimal working region toward higher pressures.
In parallel with structural optimization, the dual-mode sensing design allows coordinated utilization of temperature and pressure information. The temperature sensing unit provides real-time environmental temperature references, enabling compensation for thermally induced drift in the pressure signal and significantly improving measurement robustness in variable thermal environments. This collaborative sensing paradigm fundamentally overcomes limitations of traditional single-parameter airflow sensors, tending to lose accuracy when airflow variations and temperature fluctuations coexist.
From a manufacturing perspective, the proposed sensor structure shows good potential compatibility with scalable micro and nano fabrication technologies. Considering the structural characteristics and material system, the device can potentially be fabricated through either nanoimprint technology (NIL) or laser direct writing (LDW), and both routes are capable of realizing microstructural formation together with the construction of the CNT based sensitive layer. In the NIL route, stress concentrating features such as bosses and strain beams can be replicated with high geometric fidelity through template transfer, while CNT-polymer composite sensitive layers can be concurrently or subsequently integrated into the imprinted microstructures, indicating suitability for uniform and scalable fabrication. In the LDW route, localized laser processing can simultaneously define microstructural regions and selectively pattern CNT functional films and electrode networks on the same substrate, providing a rapid and flexible pathway for device construction. These complementary fabrication routes indicate promising engineering feasibility and scalability potential for future implementation.
In summary, this work presents an integrated airflow monitoring sensor featuring stress-induced strain amplification, dual-mode perception, temperature-adaptive compensation, and validated low-pressure superiority. The results provide new insights into structural enhancement strategies for micro-pressure sensing and deliver a feasible, high-performance, and cost-effective solution for advanced thermal management monitoring applications.
Key words
micro-pressure monitoring /
temperature sensing /
dual-mode integration /
stress-concentrating boss /
carbon nanotube (CNT) /
air inflow monitoring
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References
[1] SHEHABI A, SMITH S J, SARTOR D A, et al.United States Data Center Energy Usage Report: LBNL- 1005775[R]. Berkeley, California: Lawrence Berkeley National Laboratory, 2016
[2] HANUS N, NEWKIRK A, STRATTON H.Organizational and Psychological Measures for Data Center Energy Efficiency: Barriers and Mitigation Strategies[J]. Energy Efficiency, 2023, 16(1): 1.
[3] KATAL A, DAHIYA S, CHOUDHURY T.Energy Efficiency in Cloud Computing Data Centers: A Survey on Software Technologies[J]. Cluster Computing, 2023, 26(3): 1845-1875.
[4] WANG Y W, ZHANG Y R, NÖRTERSHÄUSER D, et al. Model and Data Driven Transient Thermal System Modelings for Contained Data Centers[J]. Energy and Buildings, 2022, 258: 111790.
[5] 袁瑞明, 章钢, 余剑宇, 等. 风机性能对服务器散热特性影响的数值研究[J]. 环境技术, 2023, 41(5): 120-126.
YUAN R M, ZHANG G, YU J Y, et al.Numerical Investigation of the Effects of Fan Performance on the Heat Dissipation Characteristics of the Server[J]. Environmental Technology, 2023, 41(5): 120-126.
[6] 刘巍, 程林. 风机串并联在电子设备散热中的应用研究[J]. 空军预警学院学报, 2020, 34(2): 117-120.
LIU W, CHENG L.Application of Fans Series and Parallel in Heat Dissipation of Electronic Equipment[J]. Journal of Air Force Early Warning Academy, 2020, 34(2): 117-120.
[7] 吴俊. 关于解决数据中心局部热点问题的研究[J]. 洁净与空调技术, 2023(1): 110-112.
WU J.Research on Solving Local Hot Issues in Data Center[J]. Contamination Control & Air-Conditioning Technology, 2023(1): 110-112.
[8] CHEN H, ZHANG H M, WU S Y, et al.Numerical Simulation and Optimisation Design for Ventilation and Heat Dissipation in High-Temperature and High-Load Indoor Substations[J]. Case Studies in Thermal Engineering, 2024, 59: 104502.
[9] XIE R, HUANG J Q, ZUO P Q, et al.Optimization of Ventilation and Heat Dissipation Structure of Transformer Room in Prefabricated Substation Based on Multi-Physics Coupling[C]//2023 IEEE 4th International Conference on Electrical Materials and Power Equipment (ICEMPE). Shanghai, China. IEEE, 2023: 1-4.
[10] RAMOS J C, BEIZA M, GASTELURRUTIA J, et al.Numerical Modelling of the Natural Ventilation of Underground Transformer Substations[J]. Applied Thermal Engineering, 2013, 51(1/2): 852-863.
[11] 裘一超, 张锋, 求少军, 等. 制冷设备散热系统优化设计及实验分析[C]// 江西省工程师联合会. 工程技术与新能源经济学术研讨会论文集(一). 浙江北峰制冷设备有限公司, 2025: 409-413.
QIU Y C, ZHANG F, QIU S J, et al.Optimization Design and Experimental Analysis of Heat Dissipation System for Refrigeration Equipment[C]//Jiangxi Provincial Federation of Engineers. Proceedings of the Academic Symposium on Engineering Technology and New Energy Economy (I). Zhejiang Beifeng Refrigeration Equipment Co., Ltd., 2025: 409-413.
[12] WAN J X, GUI X, KASAHARA S, et al.Air Flow Measurement and Management for Improving Cooling and Energy Efficiency in Raised-Floor Data Centers: A Survey[J]. IEEE Access, 2018, 6: 48867-48901.
[13] 刘学. 温度测量常见故障分析与处理[J]. 矿山机械, 2011, 39(3): 138-140.
LIU X.Analysis and Treatment of Common Faults in Temperature Measurement[J]. Mining & Processing Equipment, 2011, 39(3): 138-140.
[14] 林鸿辉. 两线制多路远传温度监测仪设计与应用[J]. 自动化仪表, 2007, 28(S1): 118-120.
LIN H H.Design and Application of Two-Wired Multi- Channel Remote Temperature Monitor[J]. Process Automation Instrumentation, 2007, 28(S1): 118-120.
[15] 王婷婷. 典型气候试验对热敏电阻电性能参数影响研究[J]. 环境技术, 2024, 42(11): 49-54.
WANG T T.Study on the Influence of Typical Climate Test on the Electrical Performance Parameters of Thermistor[J]. Environmental Technology, 2024, 42(11): 49-54.
[16] UMAR L.New Approach for Airflow Measurement Using Thermal Resistance Simulation[J]. KnE Engineering, 2016, 1(1): 1-7.
[17] TONG X, HAO B E, CHEN Z, et al.Thermal Airflow Sensor Design and Temperature Compensation Research Based on the Thermostatic Method[J]. Sensor Review, 2022, 42(5): 568-575.
[18] 朱磊. 机械通风环境中的压差控制[J]. 中华建设, 2025(8): 69-71.
ZHU L.Pressure Difference Control in Mechanical Ventilation Environment[J]. China Construction, 2025(8): 69-71.
[19] 周辉, 韩冰, 高楚霖, 等. 一种燃气轮机燃烧室压差精密测量的冗余设计[J]. 自动化应用, 2025, 66(13): 278-279.
ZHOU H, HAN B, GAO C L, et al.A Redundant Design for Precision Measurement of Pressure Difference in Gas Turbine Combustion Chamber[J]. Automation Application, 2025, 66(13): 278-279.
[20] CHOU S Y, KRAUSS P R, RENSTROM P J.Nanoimprint Lithography[J]. Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena, 1996, 14(6): 4129-4133.
[21] MOHAPATRA S, MOIRANGTHEM R S.Flexible and Disposable Plasmonic Refractive Index Sensor Using Nanoimprint Lithography[C]//Third International Conference on Photonics Solutions (ICPS 2017). SPIE, 2018, 10714: 14-20.
[22] NANKALI M, ROUHI M, JONES J, et al.Fiber Laser Writing of Highly Sensitive Nickel Nanoparticle-Incorporated Graphene Strain Sensors[J]. ACS Applied Materials & Interfaces, 2024, 16(30): 39835-39846.
[23] FIALKOVA S, YARMOLENKO S, KRISHNASWAMY A, et al.Nanoimprint Lithography for Next-Generation Carbon Nanotube-Based Devices[J]. Nanomaterials, 2024, 14(12): 1011.
[24] WANG W, CHEN Z Q, LI Y Q, et al.Laser Direct Writing of Flexible Multifunctional Airflow Sensors on the Kevlar Fabric[J]. Nano Research, 2025, 18(1): 94907062.
[25] WANG Z R, WANG S, ZENG J F, et al.High Sensitivity, Wearable, Piezoresistive Pressure Sensors Based on Irregular Microhump Structures and Its Applications in Body Motion Sensing[J]. Small, 2016, 12(28): 3827-3836.
[26] ZHANG Y, HU Y G, ZHU P L, et al.Flexible and Highly Sensitive Pressure Sensor Based on Microdome-Patterned PDMS Forming with Assistance of Colloid Self-Assembly and Replica Technique for Wearable Electronics[J]. ACS Applied Materials & Interfaces, 2017, 9(41): 35968-35976.
[27] 郝国栋, 陈欣欣, 董宇彪, 等. 钛表面微弧氧化复合碳纳米管负极材料的制备及电化学性能[J]. 表面技术, 2025, 54(15): 78-85.
HAO G D, CHEN X X, DONG Y B, et al.Preparation and Electrochemical Performance of Carbon Nanotube Composite Anode Material via Micro-Arc Oxidation on Titanium Surface[J]. Surface Technology, 2025, 54(15): 78-85.
[28] WANG H H, CEN Y M, ZENG X Q.Highly Sensitive Flexible Tactile Sensor Mimicking the Microstructure Perception Behavior of Human Skin[J]. ACS Applied Materials & Interfaces, 2021, 13(24): 28538-28545.
[29] WANG H H, YANG H M, ZHANG S, et al.3D-Printed Flexible Tactile Sensor Mimicking the Texture and Sensitivity of Human Skin[J]. Advanced Materials Technologies, 2019, 4(9): 1900147.
[30] ZHANG Z K, ZHAO W J, MA Y C, et al.A Flexible Integrated Temperature-Pressure Sensor for Wearable Detection of Thermal Runaway in Lithium Batteries[J]. Applied Energy, 2025, 381: 125191.
[31] YU C C, CHEN H L.Nanoimprint Technology for Patterning Functional Materials and Its Applications[J]. Microelectronic Engineering, 2015, 132: 98-119.
[32] 周伟平, 白石, 谢祖武, 等. 激光直写制备金属与碳材料微纳结构与器件研究进展[J]. 光电工程, 2022, 49(1): 210330.
ZHOU W P, BAI S, XIE Z W, et al.Research Progress of Laser Direct Writing Fabrication of Metal and Carbon Micro/Nano Structures and Devices[J]. Opto-Electronic Engineering, 2022, 49(1): 210330.
Funding
National Natural Science Foundation of China (22478245); Shanxi Provincial Key Research and Development Program (202402040201002)
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