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Intelligent fault diagnosis methods toward gas turbine: A review

Chinese Journal of Aeronautics 2024年第4期37卷 93-120页

作者： Xiaofeng LIU Yingjie CHEN Liuqi XIONG Jianhua WANG Chenshuang LUO Liming ZHANG Kehuan WANG School of transportation Science and Engineering Beihang UniversityBeijing 100191China Systems Engineering Research Institute China State Shipbuilding CorporationBeijing 100094China

Fault diagnosis plays a significant role in conducting condition-based maintenance and health management for gas turbines(GTs) to improve reliability and reduce costs. Various diagnosis methods developed by modeling engine systems or certain components implement faults detection and diagnosis based on the measurement of systemic parameters deviations. However, these conventional model-based methods are hindered by limitations of inability to handle the nonlinear nature, measurement uncertainty, fault coupling and other implementing problems. Recently, the development of artificial intelligence algorithms has provided an effective solution to the above problems, triggering broad researches for data-driven fault diagnosis methods with better accuracy,dynamic performance, and universality. This paper presents a systematic review of recently proposed intelligent fault diagnosis methods for GT engines, according to the classification of shallow learning methods, deep learning methods and hybrid intelligent methods. Moreover, the principle of typical algorithms, the evolution of enhanced methods, and the assessment of pros and cons are summarized to conclude the present status and look forward to the future in the field of GT fault diagnosis. Possible directions for development in method validation, information fusion, and interpretability of intelligent diagnosis methods are concluded in the end to provide insightful concepts for scholars in related fields.

关键词： Fault diagnosis Health management Gas turbine Artificial intelligence Intelligent diagnosis method

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Mechanical response of a tunnel subjected to strike-slip faulting processes,based on a multi-scale modeling method

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1281-1295页

作者： Guoguo LIU Ping GENG Tianqiang WANG Xiangyu GUO Jiaxiang WANG Ti DING Key Laboratory of transportation Tunnel Engineering Ministry of EducationChengdu 610031China College of Civil Engineering Huaqiao UniversityXiamen 361021China China Railway Design corporation Tianjin 300308China

The stick-slip action of strike-slip faults poses a significant threat to the safety and stability of underground *** this study,the north-east area of the Longmenshan fault,Sichuan,provides the geological background;the rheological characteristics of the crustal lithosphere and the nonlinear interactions between plates are described by Burger’s viscoelastic constitutive model and the friction constitutive model,respectively.A large-scale global numerical model for plate squeezing analysis is established,and the seemingly periodic stick-slip action of faults at different crust depths is *** a second model at a smaller scale,a local finite element model(sub-model),the time history of displacement at a ground level location on the Longmenshan fault plane in a stick-slip action is considered as the displacement *** integration of these models,creating a multi-scale modeling method,is used to evaluate the crack propagation and mechanical response of a tunnel subjected to strike-slip *** determinations of the recurrence interval of stick-slip action and the cracking characteristics of the tunnel are in substantial agreement with the previous field investigation and experimental results,validating the multi-scale modeling *** can be concluded that,regardless of stratum stiffness,initial cracks first occur at the inverted arch of the tunnel in the footwall,on the squeezed side under strike-slip *** smaller the stratum stiffness is,the smaller the included angle between the crack expansion and longitudinal direction of the tunnel,and the more extensive the crack expansion *** the tunnel in a high stiffness stratum,both shear and bending failures occur on the lining under strike-slip faulting,while for that in the low stiffness stratum,only bending failure occurs on the lining.

关键词： stick-slip action plate squeezing analysis multi-scale modeling method lining cracking mechanical response

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管幕预筑法施工引起的地表沉降:顶管群施工顺序的影响

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Journal of Central South University 2024年第2期31卷 576-588页

作者：杨松松章定文汪淼徐敬民沈晨张超哲 School of transportation Southeast UniversityNanjing 211189China China Road and Bridge corporation Beijing 100010China

以太原火车站下穿隧道为例,研究了封闭管幕预筑隧道在顶管阶段的地表沉降特征。首先采用数值模拟分析了3类顶管顺序,从上向下、上下同时施工和从下向上的9种工况,顶管施工顺序引起的地表沉降特征。数值模拟结果表明采用从上向下的顶管... 详细信息

以太原火车站下穿隧道为例,研究了封闭管幕预筑隧道在顶管阶段的地表沉降特征。首先采用数值模拟分析了3类顶管顺序,从上向下、上下同时施工和从下向上的9种工况,顶管施工顺序引起的地表沉降特征。数值模拟结果表明采用从上向下的顶管施工顺序引起的地表沉降量最小,为12 mm;采用从下向上的顶管施工顺序引起的地表沉降量最大,为25 mm。通过大尺寸模型试验对数值模拟结果进行了验证,模型试验结果与数值模拟结果一致,从上向下的顶管施工引起的地表沉降最小,从下向上顶管施工顺序引起的地表沉降最大。基于数值模拟与模型试验结果,确定了太原火车站北隧道的顶管群施工顺序,现场监测结果表明选择的施工方案满足沉降要求。研究结果表明,在顶管施工阶段相邻顶管之间会形成微土拱,隧道上方相邻管道之间的微土拱将组合成大的管土拱结构,可以减少隧道下方和两侧顶管阶段引起的地表沉降。因此,考虑隧道上方管土拱结构的顶管施工顺序可以减小下方顶管施工引起的地表沉降。

关键词：管幕预筑法顶管施工顺序管间土拱结构地表沉降

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Simulation of Underground Reservoir Stability of Pumped Storage Power Station Based on Fluid-Structure Coupling

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Computer Modeling in Engineering & sciences 2024年第5期139卷 1381-1399页

作者： Peng Qiao Shuangshuang Lan Hongbiao Gu Zhengtan Mao Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing100020China College of transportation Engineering Nanjing Tech UniversityNanjing210000China

Based on global initiatives such as the clean energy transition and the development of renewable energy,the pumped storage power station has become a new and significant way of energy storage and regulation,and its construction environment is more complex than that of a traditional *** particular,the stability of the rock strata in the underground reservoirs is affected by the seepage pressure and rock stress,which presents some challenges in achieving engineering safety and *** the advantages of the numerical simulation method in dealing deal with nonlinear problems in engineering stability,in this study,the stability of the underground reservoir of the Shidangshan(SDS)pumped storage power station was numerically calculated and quantitatively analyzed based on fluid-structure coupling theory,providing an important reference for the safe operation and management of the underground ***,using the COMSOL software,a suitablemechanicalmodel was created in accordance with the geological structure and project characteristics of the underground ***,the characteristics of the stress field,displacement field,and seepage field after excavation of the underground reservoir were simulated in light of the seepage effect of groundwater on the nearby rock of the underground ***,based on the construction specifications and Molar-Coulomb criterion,a thorough evaluation of the stability of the underground reservoir was performed through simulation of the filling and discharge conditions and anti-seepage strengthening *** findings demonstrate that the numerical simulation results have a certain level of reliability and are in accordance with the stress measured in the project *** underground reservoir excavation resulted in a maximum displacement value of the rock mass around the caverns of 3.56 mm in a typical section,and the safety coefficient of the parts,as determined using the Molar-Coulomb criterion,was highe

关键词： Underground reservoir fluid-structure coupling numerical simulation pumped storage power station filling and discharge

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Influence of sea-land breeze on the formation and dissipation of severe dense fog and its burst reinforcement in the Yellow Sea coastal area,China

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Science China Earth sciences 2024年第2期67卷 432-449页

作者： Ya GAO Duanyang LIU Shuqi YAN Wenjun ZHOU Hongbin WANG Fan ZU Qin MEI Chuanxiang YI Ye SHENG Key Laboratory of transportation Meteorology of China Meteorological Administration Nanjing210041China Yancheng Meteorological Bureau Yancheng224000China Nanjing Joint Institute for Atmospheric sciences Nanjing210041China Key Laboratory of Disaster Weather Chinese Academy of Meteorological SciencesBeijing100086China

Based on the global reanalysis data of the National Centers for Environmental Prediction(NCEP)/National Center for Atmospheric Research,the surface meteorological observation data,sounding data and satellite observation data,this paper comprehensively analyzes the evolution process and formation mechanism of a persistent severe dense fog process occurred on February 15–17,2015 in Yancheng,eastern *** the numerical simulation experiment of Weather Research and Forecast(WRF)model,we further analyze the impact of sea-land breeze on the formation and burst reinforcement of *** show that the precipitation caused by the southwesterly airflow in front of the upper-level trough and the low-pressure inverted trough are conducive to the formation of early rain fog,while the nighttime clear radiance under the control of surface cold high and the infiltration of weak cold advection are conducive to the formation and development of later radiation-advection *** WRF model simulates the fog evolution process,which is basically consistent with the actual fog area,and the simulation results are credible to a certain *** simulation results show that the establishment of sea breeze has an advection cooling effect on the near surface layer,which is conducive to the formation and development of the inversion layer on the near surface,providing stable stratification conditions for the formation and burst reinforcement of *** one hand,the strengthening of sea breeze circulation can continuously transport water vapor to the study *** the other,the occurrence of ultra-low level jet is favorable for the accumulation of low-level water *** the same time,the inversion intensity further strengthens,which is in favor of the burst reinforcement and long-term maintenance of fog.

关键词： Radiation-advection fog Sea-land breeze Atmospheric boundary layer Fog burst reinforcement WRF model

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In-depth understanding of transport behavior of sulfided nano zerovalent iron/reduced graphene oxide@guar gum slurry: Stability and mobility

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Journal of Environmental sciences 2024年第10期144卷 1-14页

作者： Yuheng Ma Wenhui You Zijiang Yang Zhongyu Ren Qi Jing Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China

Nanoscale zero-valent iron(NZVI),which has the advantages of small particle size,large specific surface area,and high reactivity,is often injected into contaminated aquifers in the form of ***,the prone to passivation and agglomeration as well as poor stability andmobility of NZVI limit the further application of this technology in ***,sulfided NZVI loaded on reduced graphene oxide(S-NZVI/rGO)and guar gum(GG)with shearthinning properties as stabilizers were used to synthesize S-NZVI/rGO@GG ***,TEM,and FT-IR confirmed that the dispersion and anti-passivation of NZVI were optimized in the coupled *** stability and mobility of the slurry were improved by increasing the GG concentration,enhancing the pH,and decreasing the ionic strength and the presence of Ca^(2+)ions,respectively.A modified advection-dispersion equation(ADE)was used to simulate the transport experiments considering the strain and physicochemical deposition/***,colloidal filtration theory(CFT)demonstrated that Brownian motion plays a dominant role in themigration of S-NZVI/rGO@GG slurry,and the maximummigration distance can be increased by appropriately increasing the injection ***-Derjaguin-Landau-Verwey-Overbeek(XDLVO)theory showed that the excellent stability and migration of S-NZVI/rGO@GG slurry mainly came from the GG spatial *** study has important implications for the field injection of S-NZVI/rGO@GG *** to the injection parameters,the injection range of S-NZVI/rGO@GG slurry is effectively controlled,which lays the foundation for the promotion of application in actual fields.

关键词： S-NZVI rGO Guar gum Transport Stability

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Effect of Skeleton Grain Size on the Saturation of Gas Hydrate in Natural Sediments

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Journal of Ocean University of China 2024年第3期23卷 676-682页

作者： XU Zhenqiang LI Yang College of Marine sciences Ocean University of ChinaQingdao 266100China China Petroleum&Chemical corporation Beijing 100728China

Natural gas hydrate is prospected as a new and promising,highly clean energy resource that mainly occurs in perma-frost or at continental *** formation is subject to many soil conditions,such as grain size,matrix materials,pore morphology,and *** this study,we propose that grain size is the most decisive parameter that affects the saturation of gas hydrate in sediments based on data from Ocean Drilling Program Leg 164 and Mallik 5L-38,which represent marine sediments and terrestrial sediments,*** study reveals that high gas hydrate saturation generally occurs in coarse-grained sand,regardless of whether sediment formation is homogeneous or inhomogeneous,and the sorting of sediments may affect the hydrate saturation to a certain *** grain size and sorting of sediments may be the most intuitive proxy method for a rough estimation of hydrate *** study is necessary to fully understand the relationship between hydrate morphology and sediment grain size,even though massive hydrates are typically found in fine clayey-rich sediments.

关键词： grain size saturation gas hydrates ODP Leg 164 Mallik 5L-38

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Jigsaw-Sketch: a fast and accurate algorithm for finding top-k elephant flows in high-speed networks

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Science China(Information sciences) 2024年第4期67卷 113-130页

作者： Boyu ZHANG He HUANG Yu-E SUN Yang DU Dan WANG School of Computer Science and Technology Soochow University School of Rail transportation Soochow University

Finding top-k elephant flows in high-speed networks is one of the most fundamental network measurement tasks. It is more challenging than per-flow size estimation since the IDs and sizes of top-k flows must be tracked simultaneously. Most existing studies only record the IDs of a small number of elephant flows to fit their estimators in the extremely limited high-speed on-chip memory. However, these solutions need too many memory accesses when a packet arrives to track the elephant flows with high accuracy, which limits their practicability. Therefore, this paper proposes Jigsaw-Sketch, a new algorithm to find the top-k elephant flows with much fewer memory accesses while achieving high memory efficiency and accuracy. In this design, we propose a novel two-stage jigsaw storage scheme, which can capture the candidate top-k flows from massive network steams efficiently, and further find the top-k elephant flows with high memory efficiency and only a few memory accesses for each packet. Extensive experimental results based on real network traces show that Jigsaw-Sketch improves the packet processing throughput by at least 86%, while achieving smaller memory footprints and higher accuracy compared to the SOTA.

关键词： sketch top-$k$ network measurement elephant flow high-speed networks

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Mechanical behaviors of warm and ice-rich frozen soil stabilized with sulphoaluminate cement

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Journal of Mountain Science 2024年第1期21卷 335-345页

作者： WANG Honglei ZHANG Hu ZHANG Jianming ZHANG Qi YIN Zhenhua State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of sciences Beijing 100049China School of Civil Engineering and transportation Northeast Forestry UniversityHarbin 150040China National Key Laboratory of Green and Long-Life Road Engineering in Extreme Environment CCCC First Highway Consultants Co.LtdXi'an 710065China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

The warm and ice-rich frozen soil is characterized by high unfrozen water content, low shear strength and large compressibility, which is unreliable to meet the stability requirements of engineering infrastructures and foundations in permafrost regions. In this study, a novel approach for stabilizing the warm and ice-rich frozen soil with sulphoaluminate cement was proposed based on chemical stabilization. The mechanical behaviors of the stabilized soil, such as strength and stress-strain relationship, were investigated through a series of triaxial compression tests conducted at -1.0℃, and the mechanism of strength variations of the stabilized soil was also explained based on scanning electron microscope test. The investigations indicated that the strength of stabilized soil to resist failure has been improved, and the linear Mohr-Coulomb criteria can accurately reflect the shear strength of stabilized soil under various applied confining pressure. The increase in both curing age and cement mixing ratio were favorable to the growth of cohesion and internal friction angle. More importantly, the strength improvement mechanism of the stabilized soil is attributed to the formation of structural skeleton and the generation of cementitious hydration products within itself. Therefore, the investigations conducted in this study provide valuable references for chemical stabilization of warm and ice-rich frozen ground, thereby providing a basis for in-situ ground improvement for reinforcing warm and ice-rich permafrost foundations by soil-cement column installation.

关键词： Permafrost regions Frozen soil Mechanical behavior Chemical stabilization Ground improvement Ground modification

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A synthetic differencein-differences model for the influence of CR Express on Chongqing's economy

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Railway sciences 2024年第3期3卷 295-310页

作者： Rong Zhang Qi Li School of Traffic and transportation Beijing Jiaotong UniversityBeijingChina Institute of transportation Planning China Railway Design CorporationTianjinChina

Purpose-The China-Europe Railway Express(CR Express)in Chongqing has operated regularly and undergone large-scale *** impact on Chongqing's economic growth has become increasingly evident,necessitating further research in this ***/methodology/approach-This study employs the opening of CR Express as a quasi-natural experiment,designating Chongqing,which inaugurated the CR Express in 2011,as the treatment group.13 provinces and cities that had not yet opened the CR Express until 2017 were selected as the control *** panel data from 14 provinces across China spanning from 2006 to 2017,the synthetic control method(SCM)is employed to synthetically construct *** quantify the difference in economic development levels between Chongqing with the operation of the CR express and Chongqing without its *** metrics such as gross domestic product(GDP),per capita GDP,total retail sales of consumer goods,import and export value and the proportions of the secondary and tertiary industries are employed to measure urban economic development *** is designated as the experimental group,and a double-difference model is constructed to regress the operation of the CR Express against economic development *** tests are conducted to validate the analytical ***-The results indicate that,compared to provinces without the operation of the CR Express,the initiation of the CR Express in Chongqing significantly enhances the economic development level of the *** opening of the CR Express exhibits a pronounced positive impact on Chongqing's economic development,and these findings remain robust and effective even after parallel trend tests and placebo ***-The study represents an expansion of the theoretical *** contrast to previous studies that relied on a single indicator such as GDP,this study selects six indicators from the dimensions of economy,trade and industry

关键词： CR Express Regional economic development Synthetic model Difference-indifferences method Papertype Research paper

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