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Digital twin model of gas turbine and its application in warning of performance fault

Chinese Journal of Aeronautics 2023年第3期36卷 449-470页

作者： Minghui HU Ya HE Xinzhi LIN Ziyuan LU Zhinong JIANG Bo MA 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 Capital Aerospace Machinery Corporation Limited Beijing 100076China Hangli(Group)Industrial Co. LtdChengdu 611936China

The digital twin-driven performance model provides an attractive option for the warn gas-path faults of the gas ***,three technical difficulties need to be solved:(1)low modeling precision caused by individual differences between gas turbines,(2)poor solution efficiency due to excessive iterations,and(3)the false alarm and missing alarm brought by the traditional fixed threshold *** paper proposes a digital twin model-based early warning method for gas-path faults that breaks through the above obstacles from three ***,a novel performance modeling strategy is proposed to make the simulation effect close to the actual gas turbine by fusing the mechanism model and measurement ***,the idea of controlling the relative accuracy of model parameters is *** introduction of an error module to the existing model can greatly shorten the modeling *** third solution focuses on the early warning based on the digital twin model,which self-learns the alarm threshold of the warning feature of gas-path parameters using the kernel density *** proposed method is utilized to analyze actual measured data of LM2500+,and the results verify that the new-built digital model has higher accuracy and better *** comparisons show that the proposed method shows evident superiority in early warning of performance faults for gas turbines over other methods.

关键词： Gas turbine Digital twin model Gas-path fault warning Deviation degree analysis Performance simulation

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Comparative Study of Linear Variable Flux Reluctance Machine with Linear Wound Field Flux Reversal Machine

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CES Transactions on Electrical Machines and Systems 2023年第1期7卷 73-80页

作者： Tingting Jiang Liang Xu Jinghua Ji Wenxiang Zhao the School of Electrical and Information Engineering the Jiangsu Key Laboratory of Drive and Intelligent Control for Electric Vehicleand the National Center for International Research on StructuralHealth Management of Critical ComponentsJiangsu UniversityZhenjiang 212013China IEEE

As members of doubly salient magnetless linear machines,linear variable flux reluctance(LVFR)and wound field flux reversal(LWFFR)machines inherit the merits of conventional magnetless linear machines such as low cost,high flux adjustment capability and high ***,like linear switched reluctance machine,they have a very simple and compact long secondary,which are very attractive for long stroke ***,low force capability is their major *** solve this issue,new LVFR and LWFFR machine topologies were proposed in recent work,while lacking studies on their force improvement mechanism and further force *** this paper,LVFR and LWFFR machines with improved force performance are comparatively studied with the emphasis on their force *** operation principle of the two machines is analyzed based on magnetic field harmonics produced by flux *** of air-gap flux density harmonic components to no-load back electromagnetic forces of the two machines are analyzed and the average force equation is ***,force capabilities of the both machines are investigated by means of the time-stepping finite-element analysis to verify the theoretical analysis.

关键词： Wound field Variable flux reluctance Flux reversal Linear machine Finite-element analysis

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Coumarin Glycosides Reverse Enterococci-Facilitated Enteric Infections

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Research 2025年第1期2024卷 121-134页

作者： Wenjiao Xu Guixin Yuan Yuwen Fang Xiaojia Liu Xiaowei Ma Kui Zhu National Key Laboratory of Veterinary Public Health and Safety College of Veterinary MedicineChina Agricultural UniversityBeijing 100193China Engineering Research Center of Animal Innovative Drugs and Safety Evaluation Ministry of EducationCollege of Veterinary MedicineChina Agricultural UniversityBeijing 100193China Ministry of Agriculture and Rural Affairs Key Laboratory for Crop Pest Monitoring and Green Control China Agricultural UniversityBeijing 100193China

Commensal enterococci with pathogenic potential often facilitate the growth of diverse pathogens,thereby exacerbating ***,there are few effective therapeutic strategies to prevent and intervene in enterococci-mediated polymicrobial ***,we find that enterococci at high density drive the expansion and pathogenicity of enteric Salmonella enterica serotype Typhimurium(***).Subsequently,we show that the driving role of enterococci in such infections is counteracted by dietary coumarin glycosides in ***,which are tolerant of iron-deficient environments,produceβ-glucosidases to hydrolyze coumarin glycosides into bioactive aglycones,inhibiting *** growth and ameliorating the severity of ***-induced symptoms by inducing iron ***,we demonstrate that coumarin glycosides as a common diet effectively reverse enterococci-facilitated enteric infections,providing an alternative intervention to combat polymicrobial infections.

关键词： polymicrobial infections coumarin glycosides dietary coumarin g iron limitation enterococci enteric infections commensal enterococci glucosidases

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DNA Methylation of KLRC1 and KLRC3 in Autoimmune Thyroiditis:Perspective of Different Water Iodine Exposure

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Biomedical and Environmental Sciences 2024年第9期37卷 1044-1055页

作者： Yao Chen Jinjin Liu Mengying Qu Bingxuan Ren Huaiyong Wu Li Zhang Zheng Zhou Lixiang Liu Hongmei Shen Disorders Control Centre for Endemic Disease ControlChinese Centre for Disease Control and PreventionHarbin Medical UniversityHarbin 150081HeilongjiangChina National Health Commission&Education Bureau of Heilongjiang Province Key Laboratory of Etiology and EpidemiologyHarbin Medical UniversityHarbin 150081HeilongjiangChina Heilongjiang Provincial Key Laboratory of Trace Elements and Human Health Harbin Medical UniversityHarbin 150081HeilongjiangChina Division of Health Risk Factor Monitoring and Control Shanghai Municipal Center for Disease Control and PreventionShanghai 200336China Department of Public Health Administration Affiliated Hospital of Jining Medical UniversityJining 272060ShandongChina Heze Municipal Hospital Shandong Provincial Hospital Heze HospitalHeze 274700ShandongChina

Objective This study aimed to identify differentially methylated genes(DMGs) associated with natural killer cells in patients with autoimmune thyroiditis(AIT), focusing on the influence of varying water iodine exposure *** Participants were divided into categories based on median water iodine(MWI)concentrations: iodine-fortified areas(IFA, MWI < 10 μg/L), iodine-adequate areas(IAA, 40 ≤ MWI ≤ 100μg/L), and iodine-excessive areas(IEA, MWI > 300 μg/L). A total of 176 matched AIT cases and controls were recruited and divided into 89, 40, and 47 pairs for IFA, IAA, and IEA, respectively. DMGs were identified using 850K Bead Chip analysis for 10/10 paired samples. Validation of DNA methylation and m RNA expression levels of the DMGs was conducted using Methyl Target^(TM) and QRT-PCR for 176/176paired *** KLRC1, KLRC3, and SH2D1B were identified as significant DMGs. Validation revealed that KLRC1 was hypomethylated and highly expressed, whereas KLRC3 was hypermethylated and highly expressed in individuals with AIT. Furthermore, KLRC1 was hypomethylated and highly expressed in both IFA and *** The DNA methylation status of KLRC1 and KLRC3 may play crucial roles in AIT pathogenesis. Additionally, DNA methylation of KLRC1 seems to be influenced by different iodine concentrations in water.

关键词： Autoimmune thyroiditis DNA methylation KLRC1 KLRC3 SH2D1B Iodine

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Soil amendment strategies determining microbial community composition and their assembly processes in a continuously cropped soil

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Soil Ecology Letters 2024年第3期6卷 85-95页

作者： Hongkai Liao Chunli Zheng Juan Li Jian Long Yaying Li Guizhou Provincial Key Laboratory of Mountain Environment Guizhou Normal UniversityGuiyang 550001China The Key Laboratory of Environmental Pollution Monitoring and Disease Control Ministry of EducationDepartment of ToxicologySchool of Public HealthGuizhou Medical UniversityGuiyang 550025China Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Laboratory of Urban Environmental Processes and Pollution Control Ningbo(Beilun)Zhongke Haixi Industry Technology Innovation CenterNingbo 315800China

Reductive soil disinfestation(RSD)is an important tool for sustainable agricultural ***,the differences in soil bacterial communities and their community assembly processes among RSD and other treatment strategies(e.g.,biochar and chemical fumigation)are still subject to open *** this study,soils subjected to various treatments–un-treated control(CK),chemical soil fumigation with CaCN_(2)(CF),1% biochar(1%B),3% biochar(3%B),and reductive soil disinfestation(RSD)are *** samples were collected,incubated,and then used for growth of tomato *** Sloan neutral community model indicates that stochastic processes dominate in bacterial community assembly for both biochar and CF *** contrast,this work shows that RSD treatment can have a strong impact on soil bacterial community *** relative abundance of Firmicutes increased during unplanted soil incubation,whereas Proteobacteria and Bacteroidetes dominated in the rhizosphere after planting of *** stochasticity ratio reveals that deterministic selection played an important role in the bacterial assembly under RSD *** found that RSD amendment yielded lower biomass than that for other treatments after 28 days of tomato *** results suggest that although RSD treatment has great potential to rebuild soil bacterial ecology by shaping bacterial communities and their assembly processes,it is important to monitor and manage soil conditions(e.g.,soil nutrients or physical properties)before planting to ensure plant productivity.

关键词： amendment strategy reductive soil disinfestation bacterial community assembly processes

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FINITE ELEMENT-BASED COMPRESSION SIMULATION AND PERMEATION PERFORMANCE MEASUREMENT AND control OF HIGH TEMPERATURE SEALING MATERIALS

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UPB Scientific Bulletin, Series D: Mechanical Engineering 2023年第2期85卷 103-118页

作者： Chen, Lifang Guo, Yixiang Key Lab of Engine Health Monitoring Control and Networking of Ministry of Education Beijing University of Chemical Technology Beijing100029 China State Key Laboratory of High-end Compressor and System Technology Beijing University of Chemical Technology Beijing100029 China

To obtain the characteristic operational parameters of spacecraft heat seals, a customized tester is used to carry out the structure and performance research of the P-shaped heat seals. A heat-sealing test system is built to simulate real working conditions. The structure and the plan of the tester are optimized based on the finite element thermal analysis method. For different compression rates and pore-opening structures, the leakage rates of the P-shaped seal are tested at room temperature, high temperature, and different air pressures. The test results show that the leakage of the P-shaped sealing ring decreases with the increase of compression rate and the number of openings on the outer high-pressure side. These results are following those of the finite element theoretical analysis. The main control factors that affect the size of seal leakage have been preliminarily determined, and the data obtained from the test has laid the foundation for future research on sealing theory. © 2023, Politechnica University of Bucharest. All rights reserved.

关键词： Seals

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Research on mechanical wear life feature fusion prediction method based on temporal pattern attention mechanism

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High Technology Letters 2023年第1期29卷 12-21页

作者：江志农 CHEN Yuyang ZHANG Jinjie LI Zhaoyang MAO Zhiwei ZHI Haifeng LIU Fengchun Beijing Key Laboratory of Health Monitoring and Self-Healing of High-end Mechanical Equipment Beijing University of Chemical TechnologyBeijing 100029P.R.China Key Laboratory of Engine Health Monitoring-control and Networking Ministry of EducationBeijing University of Chemical TechnologyBeijing 100029P.R.China China North Engine Research Institute(Tianjin) Tianjin 300400P.R.China

In order to solve the problem of low prediction accuracy when only vibration or oil signal is used to predict the remaining life of gear wear,a gear wear life feature fusion prediction method based on temporal pattern attention mechanism is ***,deep residual shrinkage network(DRSN)is used to extract the features of the original vibration time series signals with low signal-tonoise ratio,and the vibration features associated with gear wear evolution are ***,the extracted vibration features and the oil monitoring data that can intuitively reflect the wear process information are jointly input into the bi-directional long short-term memory neural network based on temporal pattern attention mechanism(TPA-BiLSTM),the complex nonlinear relationship between vibration features,oil features and gear wear process evolution is further explored to improve the prediction *** gear life cycle dynamic response and wear process signals are obtained based on the gear numerical simulation model,and the feasibility of the proposed method is ***,the proposed method is applied to the residual life prediction of gear on a test bench,and the comparison between different methods proved the validity of the proposed method.

关键词： prediction of gear remaining useful life information fusion numerical simulation neural network oil monitoring

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The construction method of typical engine fault identification model based on Simulink

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IFAC-PapersOnLine 2024年第29期58卷 19-24页

作者： Xin bo Zhu Cheng Hu RuiJie Jiang Zhinong Gao Zhilong Key Laboratory of Engine Health Monitoring-Control and Networking Ministry of Education Beijing University of Chemical Technology Beijing China China North Engine Research Institute Tianjin China Key Laboratory of Engine Health Monitoring-Control and Networking Ministry of Education Beijing Key Laboratory of Health Monitoring Control and Fault Self-Recovery for High-end Machinery Beijing University of Chemical Technology Beijing China

This paper provides a summary and overview of methods for constructing typical fault identification model for diesel engines based on Simulink, aiming at improving the efficiency of engine fault diagnosis and maintenance. First of all, the common types of diesel engine faults were analyzed, including intake and exhaust system faults, cooling system faults, lubrication system faults and fuel system faults. Then, the basic steps and methods of Simulink modeling are introduced in detail, by using data acquisition and preprocessing techniques, a large amount of sensor data was converted into signals that can be used as inputs. Next, this paper discussed the specific process of the fault identification model, including the data reading module, speed discrimination module, threshold discrimination module and state identification module, and the feasibility of the model is verified through practical application cases. The research show that the fault identification model based on Simulink can effectively improve the accuracy and efficiency of engine fault diagnosis, providing a new technical method to enhance the operational safety and reliability of engines, and also offering valuable reference for subsequent related research.

关键词： Diesel Engine Fault Identification Model Construction Simulink

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Multi-Material Topology Optimization for Spatial-Varying Porous Structures

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Computer Modeling in Engineering & Sciences 2024年第1期138卷 369-390页

作者： Chengwan Zhang Kai Long Zhuo Chen Xiaoyu Yang Feiyu Lu Jinhua Zhang Zunyi Duan State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing102206China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou510640China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing100124China Institute of Structural Health Monitoring and Control School of MechanicsCivil Engineering&ArchitectureNorthwestern Polytechnical UniversityXi’an710072China

This paper aims to propose a topology optimization method on generating porous structures comprising multiple *** mathematical optimization formulation is established under the constraints of individual volume fraction of constituent phase or total mass,as well as the local volume fraction of all *** original optimization problem with numerous constraints is converted into a box-constrained optimization problem by incorporating all constraints to the augmented Lagrangian function,avoiding the parameter dependence in the conventional aggregation ***,the local volume percentage can be precisely *** effects including the globalmass bound,the influence radius and local volume percentage on final designs are exploited through numerical *** numerical results also reveal that porous structures keep a balance between the bulk design and periodic design in terms of the resulting *** results,including those for irregular structures andmultiple volume fraction constraints,demonstrate that the proposedmethod can provide an efficient solution for multiple material infill structures.

关键词： Topology optimization porous structures local volume fraction augmented lagrangian multiple materials

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Reduction of Unipolar Leakage Flux and Torque Ripple in Consequent-pole PM Vernier Machine

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CES Transactions on Electrical Machines and Systems 2023年第1期7卷 35-44页

作者： Liang Xu Yang Li Wenxiang Zhao Guohai Liu the School of Electrical and Information Engineering Jiangsu UniversityZhenjiang212013China the Jiangsu Key Laboratory of Drive and Intelligent Control for Electric Vehicle and the National Center for International Research on Structural Health Management of Critical ComponentsJiangsu UniversityZhenjiang212013China IEEE

This paper proposes a new consequent-pole permanent magnet vernier machine(CPMVM),which can be regarded as a combination of two conventional CPMVM with opposite *** on the simplified axial magnetic circuit model,it is verified that the proposed CPMVM can reduce the unipolar leakage *** order to reduce the torque ripple of machine and improve the output torque of machine,the flux barrier is placed on the rotor of the proposed ***,the parameters of the proposed CPMVM are optimized and ***,the electromagnetic performance,including no-load air-gap flux density,average torque and torque ripple,flux linkage,back-electromotive force,cogging torque,average torque,torque ripple,power factor and loss,is compared with conventional surface-mounted permanent magnet vernier machine(SPMVM)and ***,it is demonstrated that proposed CPMVM with flux barrier can effectively reduce the unipolar leakage flux and greatly reduce the torque ripple of ***,compared with the SPMVM,the proposed CPMVM with flux barrier saves more than 45%of the permanent magnet material without reducing output torque.

关键词： Consequent-pole Permanent magnet vernier machine Unipolar leakage flux Torque ripple Flux barrier Output torque

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