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Actuator fault diagnosis and severity identification of turbofan engines for steady-state and dynamic conditions

Chinese Journal of Aeronautics 2025年第1期38卷 427-443页

作者： Yuzhi CHEN Weigang ZHANG Zhiwen ZHAO Elias TSOUTSANIS Areti MALKOGIANNI Yanhua MA Linfeng GOU School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China Sichuan Gas Turbine research Establishment Aero Engine Corporation of ChinaChengdu 610500China propulsion and Space research Center Technology Innovation InstituteAbu Dhabi 9639United Arab Emirates School of Integrated Circuits Dalian University of TechnologyDalian 116023China

Actuator faults can be critical in turbofan engines as they can lead to stall,surge,loss of thrust and failure of speed ***,fault diagnosis of gas turbine actuators has attracted considerable attention,from both academia and ***,the extensive literature that exists on this topic does not address identifying the severity of actuator faults and focuses mainly on actuator fault detection and *** addition,previous studies of actuator fault identification have not dealt with multiple concurrent faults in real time,especially when these are accompanied by sudden failures under dynamic *** study develops component-level models for fault identification in four typical actuators used in high-bypass ratio turbofan engines under both dynamic and steady-state conditions and these are then integrated with the engine performance model developed by the *** research results reported here present a novel method of quantifying actuator faults using dynamic effect *** maximum error for each actuator is less than0.06%and 0.07%,with average computational time of less than 0.0058 s and 0.0086 s for steady-state and transient cases,*** results confirm that the proposed method can accurately and efficiently identify concurrent actuator fault for an engine operating under either transient or steady-state conditions,even in the case of a sudden *** research results emonstrate the potential benefit to emergency response capabilities by introducing this method of monitoring the health of aero engines.

关键词： Turbofan engines Actuators Real time systems Fault identification Steady-state conditions Dynamic conditions

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Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期34卷 268-282页

作者： ZHENG Weilin WANG Qijiao XIAO Huahua CHEN Xiaoxiao XIE Fan ZENG Wen Liaoning Key Lab of Advanced Test technology for Aerospace propulsion System Shenyang Aerospace UniversityShenyang 110136China State Key Laboratory of Fire Science University of science and Technology of ChinaHefei 230027China AVIC Shenyang Aircraft Design and research Institute Shenyang 110035China

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature(T=300-400 K),initial pressure(P=0.1-0.3 MPa),turbulence intensity(u'=1.0-2.7 m/s),oxygen volumetric percentage(φ(O_(2))=15%-21%)and carbon dioxide volumetric percentage(φ(CO_(2))=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale(D6-D8)disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词： geometry characteristics large-scale wrinkling wavelet decomposition network topology fan-stirred turbulent combustor

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HfC–HfO2 modified high/superhigh temperature thermal protection coating for superior hot corrosion resistance and antioxidation performance

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Journal of Advanced Ceramics 2025年第1期14卷 177-191页

作者： Zhiyun Ye Shuqi Wang Shuang Yu Xinrui Zhao Yongchun Zou Guoliang Chen Lei Wen Lina Zhao Guangxi Zhang Yaming Wang Jiahu Ouyang Dechang Jia Yu Zhou State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001China Institute for Advanced Ceramics Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Advanced Structure-Function Integrated Materials and Green Manufacturing technology Harbin Institute of TechnologyHarbin 150001China National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China Xi’an Aerospace Composites research Institute Academy of Aerospace Propulsion TechnologyXi’an 710025China

With advances in the thrust-weight ratio,the service temperature of gas turbine engines even exceeds 1500℃,which is urgent for the development of high/superhigh-temperature thermal protection systems(TPSs)for long-term *** alloys are increasingly viewed as promising structural materials for high-temperature applications because of their superior high-temperature mechanical strength,but the“pest”catastrophic oxidation greatly restricts their further *** this study,a HfC–HfO2-modified silicide coating was prepared via an innovative method of halide-activated pack cementation(HAPC)combined with liquid-plasma-assisted particle deposition and sintering of niobium alloys,resulting in a composite coating with excellent hot corrosion resistance and high-temperature oxidation *** modified multilayer coating is characterized by the synergistic combination of a dense NbSi2 inner layer and a HfC–HfO2 porous outer layer,resulting in a significant improvement in high-temperature performance compared with that of the single NbSi2 *** corrosion gain of the composite coating is only 13.94 mg·cm−2 after a corrosion time of 200 h at 900℃,and an intact oxide scale surface is observed after oxidation at 1500℃for 500 *** improvement is attributed to the formation of a robust Hf-rich skeleton provided by the deposited HfC–HfO2 layer,which can accelerate the formation of a highly stable corroded layer/oxide *** addition,multiple stress release mechanisms of the composite coating at high temperatures also provide substantial contributions to long-term *** these merits make HfC–HfO2-modified composite coatings on niobium alloys competitive for the development of high/superhigh-temperature thermal protection systems for long-term service.

关键词： thermal protection coating niobium alloys hot corrosion resistance high-temperature oxidation resistance stress releasemechanism

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Integrating machine learning and human use experience to identify personalized pharmacotherapy in Traditional Chinese Medicine:a case study on resistant hypertension

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Journal of Traditional Chinese Medicine 2025年第1期45卷 192-200页

作者： CHE Qianzi LIU Dasheng XIANG Xinghua TIAN Yaxin XIE Feibiao XU Wenyuan LIU Jian WANG Xuejie WANG Liying BAI Weiguo HAN Xuejie YANG Wei Department of Medical Statistics Institute of Basic Research in Clinical MedicineChina Academy of Chinese Medical Sciences Department of Science and Education Medical Statistics Teaching and Research OfficeInstitute of Basic Research in Clinical MedicineChina Academy of Chinese Medical Sciences Computer Department Xiyuan Hospital of the China Academy of Chinese Medical Sciences Traditional Chinese Medicine Standards research Center Medical Statistics Teaching and Research OfficeInstitute of Basic Research in Clinical MedicineChina Academy of Chinese Medical Sciences

OBJECTIVE: To enhance the understanding of identifying personalized pharmacotherapy options in Traditional Chinese Medicine(TCM), and further support the registration of new TCM drugs. METHODS: Generalized Boosted Models and XGBoost were employed to construct a classification model to identify the bad prognosis factors in resistant hypertension(RH) patients. Furthermore, we used association analysis to explore the rules of "symptomsyndrome" and "symptom-herb" for the major influencing factors, in order to summarize prescription pattern and applicable patients of TCM. RESULTS: Patients with major adverse cardiac events mostly have complex symptoms of phlegm, stasis, deficiency and fire intermingled with each other, and finally summarized the human experience of using Chinese herbal medicine to precisely intervene in some symptoms of RH patients on the basis of conventional Western medical treatment. CONCLUSIONS: Machine learning algorithms can make full use of human use experience and evidence to save clinical trial resources and accelerate the development of TCM varieties.

关键词： human clinical experience machine learning new drugs registration personalized pharmacotherapy

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Status analysis on sputtering and erosion evaluation methods of ion optic systems

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Chinese Journal of Aeronautics 2025年第1期38卷 254-270页

作者： Long MIAO Tongxun YANG Zhengxi ZHU Chang LU Zhiwen WU Ningfei WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 404100China Advanced Aerospace Power and Energy research Center Beijing Institute of TechnologyZhuhai 519088China

In the past few decades,ion engines have been widely used in deep-space propulsion and satellite *** aim of extending the thruster lifetime is still one of the most important parts during the design stage of ion *** one of the core components of ion engine,the grid assembly of ion optic systems may experience long-term ion sputtering in extreme electro-thermal environments,which will eventually lead to its structural and electron-backstreaming *** this paper,the current studies of the grid assembly erosion process are systematically analyzed from the aspects of sputtering damage process of grid materials,numerical simulations,and measurements of erosion characteristics of grid *** advantages and disadvantages of various erosion prediction models are highlighted,and the key factors and processes affecting the prediction accuracy of grid assembly erosion patterns are *** different types of experimental methods of grid assembly erosion patterns are *** analysis in this paper is of great importance for selecting the sputter-resistant grid materials,as well as establishing the erosion models and measurement methods to accurately determine the erosion rate and failure modes of grid ***,the working conditions and structure parameters of ion optic systems could be optimized based on erosion models to promote the ion engine lifetime.

关键词： Electric propulsion Ion optic systems Sputtering yield Erosion characteristics Erosion pattern measurement Lifetime evaluation

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Analysis of a Hail Process in Foshan, Guangdong Province Using an Advanced Phased-Array Radar System and Development of a New Early Warning Index

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Journal of Meteorological research 2025年第01期 41-58页

作者： Ling YANG Jie FU Zhaoming LI Shuqing MA Wanyi WEI Yang LIU College of Electronic Engineering Chengdu University of Information Technology China Meteorological Administration Key Laboratory of Atmospheric Sounding Foshan Tornado research Center/Foshan Meteorological office of Guangdong Province CMA Meteorological Observation Centre China Meteorological Administration (CMA) Rayshon technology Co. Ltd.

Dual-Doppler radar detection and wind-field retrieval techniques are crucial for capturing small-scale structures within convective systems. The spatiotemporal resolution of radar data is a key factor influencing the accuracy of wind-field observations. Recently, an advanced X-band phased-array weather radar system was deployed in Foshan,Guangdong Province, China, comprising a central collaborative control unit and multiple networked phased-array radar front-ends. These radar front-ends work together to scan a common area, achieving a maximum data time difference of 5 s and a volume scan interval of 30 s, thereby providing three-dimensional wind-field data with higher spatiotemporal resolution and greater accuracy than achieved using traditional methods. This study utilized the Xband phased-array weather radar system to analyze the development of a substantial hailstorm that occurred over Foshan on 26 March 2022. Analysis indicated that hail cloud activity intensified considerably after 1442 local time,with the maximum reflectivity factor exceeding 60 dBZ above the altitude of the-20°C level, and reflectivity continued to increase over the subsequent 12 min. More precise information on the flow-field structure of the storm was obtained by examining the X-band radar data. The temporal and vertical variations in the maximum reflectivity factor,updraft velocity, vertical wind shear, and horizontal wind speed within a hailstorm cloud were scrutinized. The results show that the altitude, intensity, and range of the main updraft area increased as the storm core ascended. Concurrently, the vertical wind shear at mid-lower levels of the storm became more pronounced as the altitude of the strong radar echo center increased prior to the peak of the updraft. Therefore, a new hail warning index was developed by using the vertical wind shear, and the index can be used to issue warnings up to 12 min earlier than achievable using traditional methods detecting increases in hailstor

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Attenuation of Richtmyer-Meshkov instability growth of fluid layer via double shock

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Science China(Physics,Mechanics & Astronomy) 2025年第04期Mechanics & Astronomy) .卷 148-155页

作者： Chenren Chen Jiaxuan Li He Wang Zhigang Zhai Xisheng Luo Advanced propulsion Laboratory Department of Modern Mechanics University of Science and Technology of China State Key Laboratory of High-Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences

Suppression of the hydrodynamic instabilities involved in the inertial confinement fusion has attracted much attention but remains a challenge. In this work, we report the first theoretical analysis and experimental validation on attenuating the instability growth of a shock-accelerated fluid layer through a second shock impact. An analytical model is established to predict linear growth rates of the perturbations at two interfaces of the layer by considering both the effects of interface coupling and reverberating waves. Theoretically, there are nine possibilities for simultaneously attenuating the instability growths of perturbations at the two interfaces. Accordingly, shock-tube experiments are specially designed and conducted, and nine possibilities are all realized by experiments, which verifies the reliability of the analytical model and also demonstrates the feasibility of attenuating the instability growth of a fluid layer via double shock.

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Investigation of spatiotemporal distribution and formation mechanisms of ozone pollution in eastern Chinese cities applying convolutional neural network

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Journal of Environmental Sciences 2025年第2期148卷 126-138页

作者： Qiaoli Wang Dongping Sheng Chengzhi Wu Xiaojie Ou Shengdong Yao Jingkai Zhao Feili Li Wei Li Jianmeng Chen 无 College of Environment Zhejiang University of TechnologyHangzhou 310032China Key Laboratory of Biomass Chemical Engineering of the Ministry of Education Institute of Industrial Ecology and EnvironmentCollege of Chemical and Biological EngineeringZhejiang University(Zijingang Campus)Hangzhou 310027China Trinity Consultants Inc.(China office)Hangzhou 310012China Zhejiang University of Science&technology Hangzhou 310023China

Severe ground-level ozone(O_(3))pollution over major Chinese cities has become one of the most challenging problems,which have deleterious effects on human health and the sustainability of *** study explored the spatiotemporal distribution characteristics of ground-level O_(3) and its precursors based on conventional pollutant and meteorological monitoring data in Zhejiang Province from 2016 to ***,a high-performance convolutional neural network(CNN)model was established by expanding the moment and the concentration variations to general ***,the response mechanism of O_(3) to the variation with crucial influencing factors is explored by controlling variables and interpolating target *** results indicated that the annual average MDA8-90th concentrations in Zhejiang Province are higher in the northern and lower in the *** the wind direction(WD)ranges from east to southwest and the wind speed(WS)ranges between 2 and 3 m/sec,higher O_(3) concentration prone to *** different temperatures(T),the O_(3) concentration showed a trend of first increasing and subsequently decreasing with increasing NO_(2) concentration,peaks at the NO_(2) concentration around 0.02mg/m^(3).The sensitivity of NO_(2) to O_(3) formation is not easily affected by temperature,barometric pressure and dew point ***,there is a minimum IRNO_(2) at each temperature when the NO_(2) concentration is 0.03 mg/m^(3),and this minimum IRNO_(2) decreases with increasing *** study explores the response mechanism of O_(3) with the change of driving variables,which can provide a scientific foundation and methodological support for the targeted management of O_(3) pollution.

关键词： Ozone Spatiotemporal distribution Convolutional neural network Ozone formation rules Incremental reactivity

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Characteristics of Transition Layer at Soft Metal-Substrate Interface for Metal Seal

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稀有金属材料与工程 2025年第1期54卷 1-9页

作者： Zhang Dawei Zhang Xuekai Cao Zixuan Ge Ziyi Lv Shichang Li Zhijun Zhao Shengdun Hu Yanghu Xi'an Key Laboratory of Intelligent Equipment and Control School of Mechanical EngineeringXi'an Jiaotong UniversityXi'an 710049China Xi'an Aerospace propulsion Institute Xi'an 710100China Light Alloy research Institute Central South UniversityChangsha 410083China National Key Laboratory of Metal Forming technology and Heavy Equipment Xi'an 710018China

The pressure-actuated metal seal with soft metal coating has been widely used in complex working conditions such as high temperature,low temperature and high *** investigation of the characteristics and binding strength of the transition layer between the soft metal coating and the superalloy substrate is important to improve the sealing performance and to model and simplify the working through-process of metal *** distribution characteristics of elements at soft metal-substrate interface and the binding strength between coating and substrate under different thicknesses and material combinations of coating layer were studied by experimental *** results indicate that the thickness of soft metal coating has little influence on the interface morphology of GH4169-Cu,GH4169-Ag and Cu-Ag,but has an influence on the thickness of transition layer between different metals,while this influence is weakened with increasing the coating thickness,and the thickness of transition layer is about 2μm when the coating thickness is more than 30μ*** cross-cut test shows that the Cu,Ag and Cu-Ag coatings are all well combined with nickel-based superalloy GH4169 *** materials of soft metal,*** coating materials,have significant influence on the characteristic of transition layer and the surface characteristics of coating after cross-cut test.

关键词： pressure-actuated metal seal nickel-based superalloy copper coating silver coating element transition layer

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Hotspots and trends in stem cell therapy for liver fibrosis and cirrhosis: A bibliometric analysis

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World Journal of Hepatology 2025年第1期17卷 112-131页

作者： Wen-Yan Zhu Xiang Li Jia-Ling Xie Qin Lu Ying-Jie Ma Zhao-Jing Zhu Juan Liu Chongqing Engineering research Center of Pharmaceutical Sciences Chongqing Medical and Pharmaceutical CollegeChongqing 401331China College of Pharmacy Chongqing Medical UniversityChongqing 400016China Department of Cardiology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Immunology research Center of Medical research Institute Southwest UniversityChongqing 402460China office of Scientific research of Army Medical Center Army Medical UniversityChongqing 400042China

BACKGROUND Liver fibrosis and cirrhosis are global medical challenges that require safe and effective *** the past two decades,there has been a surge in research on stem cell therapy for liver fibrosis and *** study aimed to conduct a comprehensive analysis of the research hotspots and trends in this field through *** was *** As of September 20,2024,a total of 1935 documents were retrieved dating from 2004 to 2024,with 1186 strongly relevant publications obtained after ***,the United States,and Japan were the major contributors in this *** University,Zhejiang University and Yamaguchi University were the major institution in this *** journal Stem Cell research&Therapy published the most *** were 686 authors,with Shuji Terai,Isao Sakaida,Soon Koo Baik,and Lanjuan Li publishing the most *** research focused on alcoholic cirrhosis and nonalcoholic fatty liver *** emerging areas of interest were extracellular vesicles,exosomes,and their enriched *** field is experiencing rapid growth due to the changing research trends and increasing *** These findings provide a thorough overview of stem cell therapy in the field of liver fibrosis and cirrhosis.

关键词： Liver fibrosis Cirrhosis Stem cell therapy Mesenchymal stromal cell Extracellular vesicles Exosomes Bibliometrics

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