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Intelligent fault diagnosis methods toward gas turbine: A review

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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

How does trip frequency distort time value to impact congestion charging schemes?

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transportation Safety and Environment 2024年第1期6卷 22-39页

作者： Maosheng Li Hangcong Li School of Traffic and transportation engineering Central South UniversityChangshaHunan 410075China

A notable feature of a city or region with close economic and social connections with its neighbours is its highly mixed local and external traffic,and in some cases the external traffic volume is almost as high as that of local *** local traffic volume may be largely made up of the same regular local commuters making frequent trips,external traffic from outside of the city(region)may not be the same people making regular trips to/from the ***,from a large pool of people making infrequent trips to/from the city,the existence of external traffic is proven by data from the licence plate recognition system of road vehicles in Changde,*** function of value of time correlated with the income/wage rate and trip frequency is exploited and verified *** time value distorted by trip frequency is defined as perceived time value(PTV),which also influences the way travellers perceive any travel impedance such as congestion delay and toll *** paper analyses the price of anarchy(POA)when explicitly considering the travel frequency of the trip-makers and their PTV,and compares with previous analysis without considering travel *** show that when travel frequency is considered,the optimal toll of congested road pricing schemes which converts road traffic flow from user equilibrium into system optimization is much lower than that without considering travel *** cost of licence plate auction cannot be treated as a congestion toll,which is only a threshold of vehicle *** travellers choose routes by PTV rather than TV(time value)is proven by an example of Heishipu Bridge in Changsha,Hunan Province,China.

关键词： road congestion charging travel frequency perceived time value road traffic impedance price of anarchy

Smoothed-Particle Hydrodynamics Simulation of Ship Motion and Tank Sloshing under the Effect of Regular Waves

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1045-1061页

作者： Mingming Zhao Jialong Jiao School of Civil engineering and transportation South China University of TechnologyGuangzhou510641China

Predicting the response of liquefied natural gas(LNG)contained in vessels subjected to external waves is extremely important to ensure the safety of the transportation *** this study,the coupled behavior due to ship motion and liquid tank sloshing has been simulated by the Smoothed-Particle Hydrodynamics(SPH)***,the sloshing flow in a rectangular tank was simulated and the related loads were analyzed to verify and validate the accuracy of the present SPH ***,a three-dimensional simplified LNG carrier model,including two prismatic liquid tanks and a wave tank,was *** conditions were examined corresponding to different wave lengths,wave heights,wave heading angles,and tank loading ***,the effects of liquid tank loading rate on LNG ship motions and sloshing loading were analyzed,thereby showing that the SPH method can effectively provide useful indications for the design of liquid cargo ships.

关键词： LNG carrier tank sloshing seakeeping inner and external fluid coupling Smoothed Particle Hydrodynamics(SPH)

Effects of grain's shape-and size-polydispersities,orientation,and area fraction on tortuosity and permeability of 2D granular media

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Particuology 2024年第7期90卷 535-557页

作者： Ke Cao Huisu Chen Mohammad Iqbal Khan Mingqi Li Lin Liu Jiangsu Key Laboratory of Construction Materials School of Materials Science and EngineeringSoutheast UniversityNanjing 211189China Department of Civil engineering College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia School of Civil and transportation engineering Hebei University of TechnologyTianjin 300401China College of Civil and transportation engineering Hohai UniversityNanjing210098China

The microstructure of granular media, including grain's shape- and size-polydispersities, orientation, and area fraction can potentially affect its permeability. However, few studies consider the coupling effects of these features. This work employs geometrical probability and stereology to establish quantitative relationships between the above microstructural features and the geometric tortuosity of the two-dimensional granular media containing superellipse, superoval, and polygon grains. Then the lattice Boltzmann method (LBM) is used to determine the permeabilities of these granular media. By combining the tortuosity model and the LBM-derived permeabilities, modified K–C equations are formulated to predict the permeability and the shape factor, considering the grain's shape- and size-polydispersities, orientation, and area fraction. The reliability of these methods can be verified by comparing them with both our simulations and available experimental, theoretical, and numerical data reported in the literature. The findings implicate that the tortuosity and permeability of the granular media are strongly correlated with the grain's shape, orientation, and area fraction but unaffected by the size polydispersity and spatial arrangement of grains. Only circularity is not enough to derive a unified formula for considering the impact of grain shape on tortuosity and permeability, other shape parameters need to be explored in the future.

关键词： Geometric tortuosity Konzey-Carman equation Shape and size ploydispersities Grain orientation Lattice Boltzmann method Granular media

A pressure-sensitive rheological origin of high friction angles of granular matter observed in NASA–MGM project

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Chinese Physics B 2024年第6期33卷 559-567页

作者：程晓辉肖世泽杨森赵乃峰 Alex Sixie Cao Department of Civil engineering Tsinghua UniversityBeijing 100084China College of transportation engineering Nanjing Tech UniversityNanjing 211816China Institute of Structural engineering ETH ZurichZurich 8092Switzerland

An abnormally high peak friction angle of Ottawa sand was observed in(National Aeronautics and Space Administration) NASA–(Mechanics of Granular Materials) MGM tests in microgravity conditions on the space shuttle. Previous investigations have been unsuccessful in providing a constitutive insight into this behavior of granular materials under extremely low effective stress conditions. Here, a recently proposed unified constitutive model for transient rheological behavior of sand and other granular materials is adopted for the analytical assessment of high peak friction angles. For the first time, this long-eluded behavior of sand is attributed to a hidden rheological transition mechanism, that is not only rate-sensitive, but also pressure-sensitive. The NASA–MGM microgravity conditions show that shear-tests of sand can be performed under abnormally low confining stress conditions. The pressure-sensitive behavior of granular shearing that is previously ignored is studied based on the μ(I) rheology and its variations. Comparisons between the model and the NASA microgravity tests demonstrate a high degree of agreement. The research is highly valid for pressure-sensitive and rate-dependent problems that occur during earthquakes, landslides, and space exploration.

关键词： granular matter microgravity pressure-sensitive NASA–MGM

Feature Selection Using Tree Model and Classification Through Convolutional Neural Network for Structural Damage Detection

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Acta Mechanica Solida Sinica 2024年第3期37卷 498-518页

作者： Zihan Jin Jiqiao Zhang Qianpeng He Silang Zhu Tianlong Ouyang Gongfa Chen School of Civil and transportation engineering Guangdong University of TechnologyGuangzhou510006China Guangdong Tianxin Electric Power engineering Testing Co. LtdGuangzhou510663China

Structural damage detection(SDD)remains highly challenging,due to the difficulty in selecting the optimal damage features from a vast amount of *** this study,a tree model-based method using decision tree and random forest was employed for feature selection of vibration response signals in *** datasets were obtained by numerical experiments and vibration experiments,*** features extracted using this method were input into a convolutional neural network to determine the location of structural *** indicated a 5%to 10%improvement in detection accuracy compared to using original datasets without feature selection,demonstrating the feasibility of this *** proposed method,based on tree model and classification,addresses the issue of extracting effective information from numerous vibration response signals in structural health monitoring.

关键词： Feature selection Structural damage detection Decision tree Random forest Convolutional neural network

Development and optimization of object detection technology in pavement engineering: A literature review

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Journal of Road engineering 2024年第2期4卷 163-188页

作者： Hui Yao Yaning Fan Yanhao Liu Dandan Cao Ning Chen Tiancheng Luo Jingyu Yang Xueyi Hu Jie Ji Zhanping You Beijing Key Laboratory of transportation engineering Faculty of ArchitectureCivil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China School of Civil and transportation engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Department of Civil and Environmental engineering Michigan Technological UniversityHoughtonMI 49931USA

Due to the rapid advancement of the transportation industry and the continual increase in pavement infrastructure,it is difficult to keep up with the huge road maintenance task by relying only on the traditional manual detection *** pavement detection technology with deep learning techniques is available for the research and industry areas by the gradual development of computer vision *** to the different characteristics of pavement distress and the uncertainty of the external environment,this kind of object detection technology for distress classification and location still faces great *** paper discusses the development of object detection technology and analyzes classical convolutional neural network(CNN)*** addition to the one-stage and two-stage object detection frameworks,object detection without anchor frames is introduced,which is divided according to whether the anchor box is used or *** paper also introduces attention mechanisms based on convolutional neural networks and emphasizes the performance of these mechanisms to further enhance the accuracy of object *** network architecture is introduced for mobile and industrial *** stereo cameras and sensors are rapidly developed,a detailed summary of three-dimensional object detection algorithms is also *** reviewing the history of the development of object detection,the scope of this review is not only limited to the area of pavement crack detection but also guidance for researchers in related fields is shared.

关键词： Pavement engineering Object detection Lightweight network Attention mechanism Convolutional neural network

Dynamic Response of A Group of Cylindrical Storage Tanks with Baffles Considering the Effect of Soil Foundation

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China Ocean engineering 2024年第1期38卷 129-143页

作者： SUN Ying WANG Jia-dong HUO Rui-li ZHOU Ding GU Zhen-yuan QIAN Wang-ping School of transportation and Civil engineering Nantong UniversityNantong 226019China Faculty of Civil engineering and Mechanics Jiangsu UniversityZhenjiang 212013China College of Civil engineering Nanjing Tech UniversityNanjing 211816China

The sloshing in a group of rigid cylindrical tanks with baffles and on soil foundation under horizontal excitation is studied *** solutions for the velocity potential are derived out by the liquid subdomain *** models with mass-spring oscillators are established to replace continuous *** with the least square technique,Chebyshev polynomials are employed to fit horizontal,rocking and horizontal-rocking coupling impedances of soil,respectively.A lumped parameter model for impedance is presented to describe the effects of soil on tank structures.A mechanical model for the soil-foundation-tank-liquid-baffle system with small amount of calculation and high accuracy is proposed using the substructure *** analytical solutions are in comparison with data from reported literature and numerical codes to validate the effectiveness and correctness of the *** dynamic properties and seismic responses of the soil-tank system are given for the baffle number,size and location as well as soil parameter.

关键词： cylindrical tanks multiple annular baffles equivalent analytical model soil−structure interaction subdomain method dynamic response

Chaotic Aquila Optimization Algorithm for Solving Phase Equilibrium Problems and Parameter Estimation of Semi-empirical Models

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Journal of Bionic engineering 2024年第1期21卷 486-526页

作者： Oguz Emrah Turgut Mert Sinan Turgut Erhan Kırtepe Department of Industrial engineering Faculty of Engineering and ArchitectureIzmir Bakircay UniversityMenemenizmirTurkey Department of Mechanical engineering Faculty of EngineeringEge UniversityBornovaizmirTurkey Department of Motor Vehicles and transportation Technologies Sirnak UniversitySirnakTurkey

This research study aims to enhance the optimization performance of a newly emerged Aquila Optimization algorithm by incorporating chaotic sequences rather than using uniformly generated Gaussian random *** work employs 25 different chaotic maps under the framework of Aquila *** considers the ten best chaotic variants for performance evaluation on multidimensional test functions composed of unimodal and multimodal problems,which have yet to be studied in past literature *** was found that Ikeda chaotic map enhanced Aquila Optimization algorithm yields the best predictions and becomes the leading method in most of the *** test the effectivity of this chaotic variant on real-world optimization problems,it is employed on two constrained engineering design problems,and its effectiveness has been ***,phase equilibrium and semi-empirical parameter estimation problems have been solved by the proposed method,and respective solutions have been compared with those obtained from state-of-art *** is observed that CH01 can successfully cope with the restrictive nonlinearities and nonconvexities of parameter estimation and phase equilibrium problems,showing the capabilities of yielding minimum prediction error values of no more than 0.05 compared to the remaining algorithms utilized in the performance benchmarking process.

关键词： Aquila optimization algorithm Chaotic maps Parameter estimation Phase equilibrium Unconstrained optimization