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Chinese Journal of mechanical Engineering 2023年第2期36卷 166-179页

作者： Nanyang Zhao Jinjie Zhang Zhiwei Mao Zhinong Jiang He Li beijing key laboratory of high-end mechanical equipment health monitoring and self-recovery Beijing University of Chemical TechnologyBeijing 100029China

Vibration signals have the characteristics of multi-source strong shock coupling and strong noise interference owing to the complex structure of reciprocating ***,it is difficult to extract,analyze,and diagnose mechanical fault *** accurately extract sensitive features from the strong noise interference and unsteady monitoring signals of reciprocating machinery,a study on the time-frequency feature extraction method of multi-source shock signals is *** the characteristics of reciprocating mechanical vibration signals,a targeted optimization method considering the variational modal decomposition(VMD)mode number and second penalty factor is proposed,which completed the adaptive decomposition of coupled *** at the bilateral asymmetric attenuation characteristics of reciprocating mechanical shock signals,a new bilateral adaptive Laplace wavelet(BALW)is established.A search strategy for wavelet local parameters of multi-shock signals is proposed using the harmony search(HS)method.A multi-source shock simulation signal is established,and actual data on the valve fault are obtained through diesel engine fault *** fault recognition rate of the intake and exhaust valve clearance is above 90%and the extraction accuracy of the shock start position is improved by 10°.

关键词： Shock Signal processing Wavelet VMD Fault diagnosis Diesel engine

Remaining Useful Life Prediction of Rolling Element Bearings Based on Different Degradation Stages and Particle Filter

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第3期36卷 432-441页

作者： LI Qing MA Bo LIU Jiameng beijing key laboratory of high?end mechanical equipment health monitoring and self?recovery Beijing University of Chemical Technology

A method is proposed to improve the accuracy of remaining useful life prediction for rolling element bearings,based on a state space model(SSM)with different degradation stages and a particle *** model is improved by a method based on the Paris formula and the Foreman formula allowing the establishment of different degradation *** remaining useful life of rolling element bearings can be predicted by the adjusted model with inputs of physical data and operating status *** late operating trend is predicted by the use of the particle filter *** rolling bearing full life experimental data validate the proposed ***,the prediction result is compared with the single SSM and the Gamma model,and the results indicate that the predicted accuracy of the proposed method is higher with better practicability.

关键词： different life stages of state space model remaining useful life prediction of rolling element bearing particle filter

Experimental study on vibration suppression of gear shaft misalignment with ISFD

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high Technology Letters 2019年第1期25卷 17-27页

作者： Lu Kaihua He Lidong Zhang Yipeng Chen Zhao Yan Wei beijing key laboratory of health monitoring and self-recovery for high-end mechanical equipment Beijing University of Chemical Technology

Misalignment faults in gear systems lead to violent vibration and noise, shortening the life of equipment. The aim of this work is the demonstration of vibration suppression of parallel-misaligned gear shafts using an integral squeeze film damper(ISFD). Using a first grade spur gear in engineering for reference, an open first-grade spur gear system is built and the vibration characteristics of the gear system with rigid supports and ISFD elastic damping supports are studied under different degrees of misalignment. The experimental results show that ISFD supports have excellent damping and vibration attenuation characteristics, which have improved control of the gear system vibration in horizontal, vertical and axial directions under different degrees of misalignment. This work shows that an ISFD structure can effectively suppress vibration of characteristic frequency components and resonance modulation frequency components. The test results provide evidence for the application of ISFD in vibration control of gear shaft misalignment faults in engineering.

关键词： gear shaft parallel misalignment integral squeeze film damper(ISFD) vibration suppression

Research on active disturbance rejection control method for turbine blade tip clearance

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Science China(Technological Sciences) 2019年第10期62卷 1795-1804页

作者： WANG WeiMin SHAO Xing LI QiHang Gao JinJi HAO ZeRui beijing key laboratory of health monitoring and self-recovery for high-end mechanical equipment Beijing University of ChemicalTechnologyBeijing100029China Department of mechanical Engineering Tsinghua UniversityBeijing100084China

Blade tip clearance(BTC) is one of the key factors affecting the efficiency and reliability of high performance turbomachinery such as heavy duty steam turbines, aircraft engines and other gas turbo machines. The self-adjusting ability of BTC according to the operation condition changing is important to meet the requirement of performance. In this paper, the principle and method of adjusting the BTC by controlling the axial displacement of the rotor were proposed and studied. The basic principle is that the BTC of the turbomachinery with a conical tail shroud will be affected by the axial displacement of rotor and thereby can be adjusted by controlling the axial position of rotor, which can be adjusted by the controllable oil pressure acting on the thrust bearing. To reach a higher control precision, lower noise and model perturbation, an adaptive quasi-sliding mode control(AQSMC) algorithm based on the disturbance observer(DOB) was designed, and numerical and experimental investigations were carried out. The numerical simulation results show that this algorithm can not only effectively suppress the disturbance, but also, compared with the general reaching law, effectively reduce the chattering and transient high gain switching effect of the closed-loop controller system and avoid the instability caused by the controller. Based on the DOB-AQSMC algorithm, the BTC was stabilized within 2 s with no overshoot and no misalignment in the test rig, and this algorithm achieves a better control performance than the proportion-integral-differential(PID) algorithm. These achievements can be used to push forward the intelligent turbomachinery development.

关键词： blade tip clearance turbomachinery active disturbance rejection control DOB-AQSM method

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

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

Optimal Design of Novel Electromagnetic-Ring Active Balancing Actuator with Radial Excitation

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Chinese Journal of mechanical Engineering 2021年第1期34卷 142-155页

作者： Xin Pan Xiaotian He Haiqi Wu Chuanlong Ju Zhinong Jiang Jinji Gao beijing key laboratory of health monitoring and self-recovery for high-end mechanical equipment Beijing University of Chemical TechnologyBeijing 100029China key laboratory of Engine health monitoring-Control and Networking(Ministry of Education) Beijing University of Chemical TechnologyBeijing 100029China

Imbalance vibration is a typical failure mode of rotational machines and has significant negative effects on the efficiency,accuracy,and service life of *** automatically reduce the imbalance vibration during the operational process,different types of active balancing actuators have been designed and widely applied in actual ***,the existing electromagnetic-ring active balancing actuator is designed based on an axial excitation structure which can cause structural instability and has low electromagnetic driving *** this paper,a novel radial excitation structure and the working principle of an electromagnetic-ring active balancing actuator with a combined driving strategy are presented in ***,based on a finite element model,the performance parameters of the actuator are analyzed,and reasonable design parameters are ***-locking torque measurements and comparative static and dynamic experiments are performed to validate the self-locking torque and driving efficiency of the *** results indicate that this novel active balancing actuator has sufficient self-locking torque,achieves normal step rotation at 2000 r/min,and reduces the driving voltage by 12.5%.The proposed novel balancing actuator using radial excitation and a combination of permanent magnets and soft-iron blocks has improved electromagnetic efficiency and a more stable and compact structure.

关键词： Rotational machines Imbalance vibration control Active balancing Balancing actuator Finite element analysis

Bionic Artificial self-recovery Enables Autonomous health of Machine

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Journal of Bionic Engineering 2022年第6期19卷 1545-1561页

作者： Gao Jinji key laboratory of beijing for high-end mechanical equipment health monitoring and self-recovery Beijing University of Chemical TechnologyBeijing100029China key laboratory of Engine health monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing100029China

This paper explores Engineering self-recoveries theory,which emerged from the research of Bionics to meet the great demand of modern high-risk process manufacturing and the development of aerospace *** opens a new era in which artefact s learn from natural *** the rapid development of the industrial Internet and Artificial intelligence technology,we have gained a deep understanding of the law of fault generation and development,which provides an opportunity for the emergence of Engineering self-recoveries *** self-recoveries expands the research field of Cybernetics and Engineering cybernetics,endows machines with the self-recovery mechanism,which is unique to humans and animals,and enables machines to store,supplement and activate self-recovery power to maintain body *** research on Artificial intelligence has greatly enhanced the function of imitating the human brain,but has ignored the important system and function of humans and animals to maintain their own health—the self-recovery system and self-recovery *** intelligence imitates the conscious thinking control behaviour of the human brain to realize automation and intellectualization,making machines *** self-recovery can imitate the self-recovery mechanism of human unconscious thinking,and prevent and suppress faults in operation to realize self-recovery,possibly making machines *** self-recovery technology includes self-repair,compensation,self-protection and self-recovery *** self-recoveries is the basis of the autonomous health of machines and even artificial systems,and a new research field of *** has broad application prospects in engineering.

关键词： Engineering self-recoveries Bionics Artificial self-recovery Artificial intelligence Fault self-recovery regulation

A Review on self-recovery Regulation(SR)Technique for Unbalance Vibration of high-end equipment

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Chinese Journal of mechanical Engineering 2020年第6期33卷 1-23页

作者： Xin Pan Jiaqiao Lu Jiaji Huo Jinji Gao Haiqi Wu beijing key laboratory of health monitoring and self-recovery for high-end mechanical equipment Beijing University of Chemical TechnologyBeijing100029China key laboratory of Engine health monitoring-Control and Networking(Ministry of Education) Beijing University of Chemical TechnologyBeijing100029China

The high-end equipment represented by high-end machine tools and aero-engines is the core component of the national intelligent manufacturing plan,and the mass unbalance is the main reason for its excessive vibration,that seriously impacts the operation efficiency and running life of the *** order to change the traditional way that the fault of equipment can only be repaired by human,the self-recovery mechanism of human and animal are given to the equipment in this paper,which forms the self-recovery regulation(SR)system for unbalance vibration of high-end *** system can online generate the self-recovery force to restrain the unbalance vibration of the equipment in operation,which is an important direction for the development of the equipment to the advanced intelligent *** on the basic principles of SR technique,the typical engineering application cases of this technique in the field of aeroengine and high-end machine tools are introduced,and four related studies promoting the development of this technique are summarized and analyzed in *** includes feature extraction,imbalance location,regulation method and balancing ***-recovery Regulation(SR)Technique is an important way to realize intelligent manufacturing and intelligent *** research can lay a technical foundation for the development of high-end equipment with self-health function.

关键词： Unbalance vibration self-recovery regulation Active balancing high-end equipment self-health

A novel sparse feature extraction method based on sparse signal via dual-channel self-adaptive TQWT

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Chinese Journal of Aeronautics 2021年第7期34卷 157-169页

作者： Junlin LI Huaqing WANG Liuyang SONG College of mechanical and Electrical Engineering 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

Sparse signal is a kind of sparse matrices which can carry fault information and simplify the signal at the same *** can effectively reduce the cost of signal storage,improve the efficiency of data transmission,and ultimately save the cost of equipment fault diagnosis in the aviation *** present,the existing sparse decomposition methods generally extract sparse fault characteristics signals based on orthogonal basis atoms,which limits the adaptability of sparse *** this paper,a self-adaptive atom is extracted by the improved dual-channel tunable Q-factor wavelet transform(TQWT)method to construct a self-adaptive complete ***,the sparse signal is obtained by the orthogonal matching pursuit(OMP)*** atoms obtained by this method are more flexible,and are no longer constrained to an orthogonal basis to reflect the oscillation characteristics of ***,the sparse signal can better extract the fault *** simulation and experimental results show that the selfadaptive dictionary with the atom extracted from the dual-channel TQWT has a stronger decomposition freedom and signal matching ability than orthogonal basis dictionaries,such as discrete cosine transform(DCT),discrete Hartley transform(DHT)and discrete wavelet transform(DWT).In addition,the sparse signal extracted by the self-adaptive complete dictionary can reflect the time-domain characteristics of the vibration signals,and can more accurately extract the bearing fault feature frequency.

关键词： Complete dictionary Data transmission Fault diagnosis Sparse matrices Sparse signal Wavelet transform