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Flow Field Simulation and Parameter Analysis of Hydraulic Unbalanced Bionic Self-recovery Actuator for Rotary Equipment

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Journal of Bionic Engineering 2024年第1期21卷 325-343页

作者： Wei Li Xin Pan Dehong Ge Jinji Gao Key Laboratory of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

The rotor is the most important component of rotating machinery,and the vibration produced by its mass unbalance has a serious influence on the secure and steady operation of the machine,so an effective online suppression technology is urgently needed.A new hydraulic unbalanced bionic self-recovery system is introduced,imitating the way of manually repairing faulty *** accomplish the effect of actuator mass redistribution,the technology employs pressurized air to drive the quantitative transfer of liquid in the reservoir cavity at opposite *** can complete the online adjustment of the equipment's balancing state and suppress the unbalanced vibration of equipment in real time,which gives the equipment the ability to maintain an autonomous health state and improve equipment *** composition and working principle of the system are introduced in detail,and the key performance parameters,such as the minimum running speed and the balancing liquid transfer speed,are analyzed *** fluid-solid coupling model of the actuator was established,and the two-phase flow from inside the hydraulic unbalanced bionic self-recovery actuator was simulated under multiple working conditions and the performance parameters were quantitatively analyzed.A balancing simulation test bed was built,and its effectiveness was verified by performance parameter tests and unbalanced bionic self-recovery *** experimental results show that the mass distribution adjustment of the balancing disk can be achieved using different viscosity balancing liquid,and the response of liquid viscosity 10 cSt is faster than that of liquid viscosity 100 cSt in the process of balancing liquid transfer,and the time is reduced by more than 75%;the system can reduce the simulated rotor amplitude from 18.3μm to 10.6μm online in real time,which provides technical support for the subsequent development of a new generation of bionic intelligent equipment.

关键词： Engineering self-recovery-Bionics Simulation analysis Self-recovery regulation

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Improving accuracy of damage quantification based on two-level consistency control of PZT layers

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Chinese Journal of Aeronautics 2023年第3期36卷 241-253页

作者： Yuanqiang REN Qiuhui XU Shenfang YUAN Research Center of Structural Health Monitoring and Prognosis State Key Lab of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China

structural health monitoring-based quantitative damage diagnosis technique plays a key role in real-time condition *** the current research,piezoelectric(PZT)sensor and Guided Wave(GW)based damage quantification methods are promising,which normally establish a calibration model between GW feature and damage degree by experiments on batch specimens,and then conduct the calibration model on the monitored ***,the accuracy of PZT and GW based damage quantification is affected by dispersion introduced by sensor network performance,structural material,and damage propagation among the adopted batch *** improving the accuracy of damage quantification,this paper adopts PZT layer as sensor network and creatively implements theoretical and experimental research on batch PZT layers consistency *** one hand,a two-level consistency control method based on multidimensional features-Euclidean distance is proposed to ensure the performance consistency of PZT layers placed on different *** the other hand,experimental research on typical aircraft lug structures is also carried out to evaluate the requirement on performance consistency of PZT layers when performing quantitative damage diagnosis,and further verify the proposed two-level consistency control *** results show that the accuracy of damage quantification raises by 38% when the dispersion of different PZT layers is controlled within 5%.

关键词： Consistency control Guided waves PZT layer Quantitative damage diagnosis structural health monitoring

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Acoustic emission characteristics of damage evolution of multi-scale fiber reinforced rubberized concrete under uniaxial compression and tension after being subjected to high temperatures

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Frontiers of structural and Civil Engineering 2024年第8期18卷 1237-1266页

作者： Shaoqi ZHANG Yao ZHANG Qianru LEI Yumeng YANG Yichao WANG Fei XU Zhiguo YAN Hehua ZHU Laboratory of Fire Safety School of Safety Engineering and Emergency ManagementShijiazhuang Tiedao UniversityShijiazhuang 050043China Structural Health Monitoring and Control Key Laboratory of Hebei Province Shijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

Recently developed multi-scale fiber(i.e.,CaCO3 whisker,polyvinyl alcohol(PVA)fiber,and steel fiber)reinforced rubberized concrete exhibits excellent mechanical properties and spalling resistance at high *** of macro properties such as strength and Young’s modulus cannot reveal and characterize damage mechanisms,particularly those relating to the multi-scale fiber strengthening *** this study,acoustic emission(AE)technology is applied to investigate the impact of multi-scale fiber on the damage evolution of rubberized concrete exposed to high temperatures,under the uniaxial compression and tension loading *** mechanical properties,AE event location,peak frequency,b-value,the ratio of rise time to amplitude(RA),average frequency(AF)values,and AE energy of specimens are *** results show that the number of events observed using AE gradually increases as the loading *** crumb rubber and fibers inhibit the generation and development of the *** is concluded that both the peak frequency and b-value reflect the extension process of *** the cracks develop from the micro scale to the macro scale,the peak frequency tends to be distributed in a lower frequency range,and the b-value decreases *** the peak stress point,the AE energy increases rapidly and the b-value *** specimens without multi-scale fibers exhibit brittle failure,while the specimens with fibers exhibit ductile *** addition,adding multi-scale fibers and crumb rubber increases the peak frequency in the medium and high frequency ranges,indicating a positive effect on inhibiting crack *** being subjected to high temperatures,the maximum and minimum b-values decrease,reflecting an increase in the number of initial cracks due to thermal ***,the RA and AF values are used to classify tensile and shear *** specimens fracture with more shear cracks under compression,and there are more tensile

关键词： multi-scale fibers acoustic emission fracture damage evolution rubberized concrete

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Time Synchronous Averaging Based on Cross-power Spectrum

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Chinese Journal of Mechanical Engineering 2023年第2期36卷 198-205页

作者： Ling Wang Minghui Hu Bo Ma Zhinong Jiang Key Laboratory of Engine Health Monitoring‑control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High‑end Mechanical Equipment Health Monitoring and Self‑Recovery Beijing University of Chemical TechnologyBeijing 100029China

Periodic components are of great significance for fault diagnosis and health monitoring of rotating *** synchronous averaging is an effective and convenient technique for extracting those ***,the performance of time synchronous averaging is seriously limited when the separate segments are poorly *** paper proposes a new averaging method capable of extracting periodic components without external reference and an accurate period to solve this *** this approach,phase detection and compensation eliminate all segments'phase differences,which enables the segments to be well *** effectiveness of the proposed method is validated by numerical and experimental signals.

关键词： Time synchronous averaging Phase detection Cross-power spectrum Fault diagnosis

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Source apportionment and suitability evaluation of seasonal VOCs contaminants in the soil around a typical refining-chemical integration park in China

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Journal of Environmental Sciences 2024年第3期137卷 651-663页

作者： Xu Zhao Jing Meng Qianqian Li Guijin Su Qifan Zhang Bin Shi Lingwen Dai Yong Yu Key Laboratory of Environmental Nanotechnology and Health Effects State Key Laboratory of Environmental Chemistry and EcotoxicologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China State Environmental Protection Key Laboratory of Quality Control in Environmental Monitoring China National Environmental Monitoring CenterBeijing 100012China

Accurate source apportionment of volatile organic compounds(VOCs)in soil nearby petrochemical industries prevailing globally,is critical for preventing ***,in the process,seasonal effect on contamination pathways and accumulation of soil VOCs is often ***,Yanshan Refining-Chemical Integration Park,including a carpet,refining,synthetic rubber,and two synthetic resin zones,was selected for *** variations resulted in a gradual decrease of 31 VOCs in soil from winter to summer.A method of dry deposition resistance model coupling partitioning coefficient model was created,revealing that dry deposition by gas phase was the primary pathway for VOCs to enter soil in winter and spring,with 100 times higher fux than by particle *** profiles for five zones were built by gas sampling with distinct substance indicators screened,which were used for positive matrix factorization factors *** of the five zones were 14.9%,20.8%,13.6%,22.1%,and 28.6%in winter and 33.4%,12.5%,10.7%,24.9%,and 18.5%in spring,*** variation in the soil sorption capacity of VOCs causes inter-seasonal differences in *** better correlation between dry deposition capacity and soil storage of VOCs made root mean square and mean absolute errors decrease averagely by 8.8%and 5.5%in winter compared to *** study provides new perspectives and methods for the source apportionment of soil VOCs contamination in industrial sites.

关键词： Dry deposition resistance model Positive matrix factorization model Partitioning coefficient model Contamination pathway Source profile

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On-line Updated Guided Wave-Based Gaussian Process Method for Damage Evaluation of Aircraft Structure 11

On-line Updated Guided Wave-Based Gaussian Process Method fo...

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11th European Workshop on structural health monitoring, EWSHM 2024

作者： Tong, Lin Jing, Hutao Chen, Jian Yuan, Shenfang Wang, Hui Research Center of Structural Health Monitoring and Prognosis State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and Astronautics Nanjing China

Accurate damage evaluation for an aircraft by using guided wave(GW) - based structural health monitoring (SHM) technology is in critical demand. An aircraft experiences various uncertainties during its service life, such as the time-varying environment, operational conditions, and different flight missions. Additionally, the actual aircraft structure involves complex structural forms such as varied thicknesses, stiffeners, and ribs, leading to a strong uncertainty of damage initiation and propagation. Consequently, when applied to an individual aircraft structure, the diagnosis model trained by prior data inevitably introduces errors, and the errors accumulate as the damage propagates, which brings challenges in engineering application. To achieve individual aircraft structure's more accurate damage evaluation, an on-line updated GW-based Gaussian process (GP) damage evaluation method is investigated in this paper. Multi-source data from the service and maintenance stages are utilized to continuously update and evolve the GP model, enabling its accurate evaluation throughout the long-term service life. © 2024 11th European Workshop on structural health monitoring, EWSHM 2024. All rights reserved.

关键词： Gaussian distribution

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GW-MUSIC focusing algorithm with high accuracy for composite damage diagnosis 11

GW-MUSIC focusing algorithm with high accuracy for composite...

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11th European Workshop on structural health monitoring, EWSHM 2024

作者： Zheng, Fei Yuan, Shenfang Qiu, Lei Ren, Yuanqiang Research Center of Structural Health Monitoring and Prognosis State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and Astronautics Nanjing China

The Guided Wave (GW)-based Multiple Signal Classification (MUSIC) method for damage imaging in composite structures offers high-resolution and flexible sensor array placement, demonstrating the considerable potential for precise damage localization. However, the application to aircraft composite structures, characterized by complex structural features, presents substantial challenges. These include pronounced anisotropy and diminished scattered signals from damaged sites. This paper presents a GW-MUSIC focusing algorithm for composite damage diagnosis. This method, designed for high localization accuracy, combines an anisotropy-compensated strategy to mitigate anisotropy while focusing on amplifying signals. Experimental validation on a composite structure demonstrated significant enhancements in localization precision, affirming the method's efficacy. © 2024 11th European Workshop on structural health monitoring, EWSHM 2024. All rights reserved.

关键词： anisotropy compensation Composite structures damage localization GW-MUSIC focusing algorithm

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A novel rotor dynamic balancing method based on blade tip clearance measurement without the once per revolution sensor

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Chinese Journal of Aeronautics 2025年第2期38卷 445-458页

作者： Weibo LI Weimin WANG Shuai ZHANG Jiale WANG Yulong LIN Tianqing LI Key Lab of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of High-end Compressor and System Technology Beijing University of Chemical TechnologyBeijing 100029China

The existence of the aeroengine casing,limited monitoring points,and multi-fault characteristics make obtaining the rotor’s vibration transmission characteristics challenging,resulting in difficulties accurately identifying the rotor *** paper utilizes a high-frequency composite sensor to monitor the engine’s blade tip clearance(BTC)and extracts unbalanced information from BTC signals for rotor dynamic balancing,while avoiding the need for the once per revolution(OPR)***,the vibration characteristics of the rotor-blade system under multi-fault conditions are ***,based on BTC measurement,a none OPR method and an unbalance identification method are proposed,in which the radial vibration of the blade tip in the BTC signals at different speeds is extracted and operated in the time domain to obtain the rotor unbalanced vibration,the signal is reconstructed,and cross-correlation analysis is used to accurately identify the magnitude and phase of the unbalanced ***,a rotor test bench is utilized for experimental *** results reveal that the dynamic balancing method based on the BTC signal can more precisely identify the rotor unbalance than the traditional rotor dynamic balancing *** application of this technique will effectively improve engine health management and fault prediction.

关键词： Aeroengine Rotor unbalance Composite sensor None once per revolution Blade tip clearance Dynamic balancing

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Enhanced VOC emission with increased temperature contributes to the shift of O_(3)-precursors relationship and optimal control strategy

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Journal of Environmental Sciences 2025年第4期150卷 218-229页

作者： Fangqi Qu Yuanjie Huang Yemin Shen Genqiang Zhong Yan Xu Lingling Jin Hongtao Qian Chun Xiong Fei Zhang Jiasi Shen Bingye Xu Xudong Tian Zhengning Xu Zhibin Wang Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control MOE Key Laboratory of Environment Remediation and Ecological HealthCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Jiaxing Ecological and Environment Bureau Tongxiang Branch Tongxiang 314500China Zhejiang Ecological and Environmental Monitoring Center Hangzhou 310012China Zhejiang Key Laboratory of Ecological and Environmental Monitoring Forewarning and Quality ControlHangzhou 310058China

Assessing the impact of anthropogenic volatile organic compounds(VOCs)on ozone(O_(3))formation is vital for themanagement of emission reduction and pollution *** of O_(3)and the major precursorswas conducted in a typical light industrial city in the YRD region from 1 May to 25 July in *** were the most abundant VOC group,contributing to 55.0%of TVOCs concentration(56.43±21.10 ppb).OVOCs,aromatics,halides,alkenes,and alkynes contributed 18.7%,9.6%,9.3%,5.2%and 1.9%,*** observational site shifted from a typical VOC control regime to a mixed regime from May to July,which can be explained by the significant increase of RO_(x)production,resulting in the transition of environment from NOx saturation to radical saturation with respect to O_(3)*** optimal O_(3)control strategy should be dynamically changed depending on the transition of control *** NOx saturation condition,minimizing the proportion of NOx in reduction could lead to better achievement of O_(3)*** mixed control regime,the cut percentage gets the top priority for the effectiveness of O_(3)*** VOCs sources were identified:temperature dependent source(28.1%),vehicular exhausts(19.9%),petrochemical industries(7.2%),solvent&gasoline usage(32.3%)and manufacturing industries(12.6%).The increase of temperature and radiation would enhance the evaporation related VOC emissions,resulting in the increase of VOC concentration and the change of RO_(x)*** results highlight determination of the optimal control strategies for O_(3)pollution in a typical YRD industrial city.

关键词： O_(3)pollution Volatile organic compounds Photochemical box model Source apportionment Optimal O_(3)control strategies

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Prediction of Coefficient of Restitution for Impact Elastoplastic Spheres Considering Finite Plate Thickness

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 183-193页

作者： Yunfeng Fan Hao Wang Tao Zhou Limin Zou Zhinong Jiang Minghui Hu State Key Laboratory of High-end Compressor and System Technology Beijing University of Chemical TechnologyBeijing 100029China China Ship Research and Development Academy Beijing 100101China Key Lab of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

Collisions between objects are a relatively common phenomenon in *** of collision processes can greatly contribute to solving problems such as impact-rub faults and particle *** coefficient of restitution is a critical parameter in the analysis of collision *** experiments have shown that the coefficient of restitution is closely related to the plate thickness,and the smaller the plate thickness,the more inaccurate the coefficient of restitution predicted by the existing model,which seriously affects the process of collision *** remedy this shortcoming,this paper proposes a plate thickness influence factor with the ratio of sphere diameter to plate thickness as the *** plate thickness influence factor can optimize the coefficient of restitution model to effectively predict the coefficient of restitution of impacting elastoplastic spheres with finite plate ***,the validity of the new model is verified using a large amount of experimental data.

关键词： Collision Coefficient of restitution Energy loss Sphere

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