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Chinese Journal of Aeronautics 2024年第3期37卷 404-416页

作者： Huibin SUN Meng LIU Yingzhi ZHANG Chenle WEI Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China aecc south industry company limited Zhuzhou 412002China

Due to the excellent self-centering and load-carrying capability,curvic couplings have been widely used in advanced aero-engine ***,curvic tooth surface errors lead to poor assembly *** physical-master-gauge-based indirect tooth surface error measurement and circumferential assembly angle optimization methods have the disadvantages of high cost and weak *** unknown tooth surface fitting mechanism is a big barrier to assembly precision prediction and ***,this work puts forward a data-driven assembly simulation and optimization approach for aero-engine rotors connected by curvic *** origin of curvic tooth surface error is deeply *** 5-axis sweep scan method,a large amount of high-precision curvic tooth surface data are acquired *** on geometric models of parts,the fitting mechanism of curvic couplings is uncovered for assembly precision simulation and prediction.A circumferential assembly angle optimization model is developed to decrease axial and radial assembly *** results show that the assembly precision can be predicted accurately and improved *** uncovering the essential principle of the assembly precision formation and proposing circumferential assembly angle optimization model,this work is meaningful for assembly quality,efficiency and economy improvement of multistage aero-engine rotors connected by curvic couplings.

关键词： Curvic couplings Tooth surface error Assembly precision Axial and radial runouts Circumferential assembly angle

Automatic Road Tunnel Crack Inspection Based on Crack Area Sensing and Multiscale Semantic Segmentation

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Computers, Materials & Continua 2024年第4期79卷 1679-1703页

作者： Dingping Chen Zhiheng Zhu Jinyang Fu Jilin He College of Mechanical and Electrical Engineering Central South UniversityChangsha410083China Department of Geotechnical Guangdong Hualu Transportation Technology Company LimitedGuangzhou510000China National Engineering Research Center of High-Speed Railway Construction Technology Changsha410075China

The detection of crack defects on the walls of road tunnels is a crucial step in the process of ensuring travel safetyand performing routine tunnel maintenance. The automatic and accurate detection of cracks on the surface of roadtunnels is the key to improving the maintenance efficiency of road tunnels. Machine vision technology combinedwith a deep neural network model is an effective means to realize the localization and identification of crackdefects on the surface of road *** propose a complete set of automatic inspection methods for identifyingcracks on the walls of road tunnels as a solution to the problem of difficulty in identifying cracks during manualmaintenance. First, a set of equipment applied to the real-time acquisition of high-definition images of walls inroad tunnels is designed. Images of walls in road tunnels are acquired based on the designed equipment, whereimages containing crack defects are manually identified and selected. Subsequently, the training and validationsets used to construct the crack inspection model are obtained based on the acquired images, whereas the regionscontaining cracks and the pixels of the cracks are finely labeled. After that, a crack area sensing module is designedbased on the proposed you only look once version 7 model combined with coordinate attention mechanism (CAYOLOV7) network to locate the crack regions in the road tunnel surface images. Only subimages containingcracks are acquired and sent to the multiscale semantic segmentation module for extraction of the pixels to whichthe cracks belong based on the DeepLab V3+ network. The precision and recall of the crack region localizationon the surface of a road tunnel based on our proposed method are 82.4% and 93.8%, respectively. Moreover, themean intersection over union (MIoU) and pixel accuracy (PA) values for achieving pixel-level detection accuracyare 76.84% and 78.29%, respectively. The experimental results on the dataset show that our proposed two-staged

关键词： Road tunnel crack inspection crack area sensing multiscale semantic segmentation CA-YOLO V7 DeepLab V3+

Predicting the coefficient of friction in a sliding contact by applying machine learning to acoustic emission data

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Friction 2024年第6期12卷 1299-1321页

作者： Robert GUTIERREZ Tianshi FANG Robert MAINWARING Tom REDDYHOFF Tribology Group Department of Mechanical EngineeringImperial College LondonExhibition RoadLondon SW72AZUK Shell Global Solutions(US)Inc.Shell Technology Center Houston 3333 Highway 6 SouthHoustonTX 77082USA Shell International Petroleum company limited Shell CentreYork RoadLondon SE17NAUK

It is increasingly important to monitor sliding interfaces within machines,since this is where both energy is lost,and failures *** emission(AE)techniques offer a way to monitor contacts remotely without requiring transparent or electrically conductive ***,acoustic data from sliding contacts is notoriously complex and difficult to ***,we simultaneously measure coefficient of friction(with a conventional force transducer)and acoustic emission(with a piezoelectric sensor and high acquisition rate digitizer)produced by a steel‒steel rubbing *** data is then used to train machine learning(ML)algorithms(e.g.,Gaussian process regression(GPR)and support vector machine(SVM))to correlated acoustic emission with *** training requires the dense AE data to first be reduced in size and a range of processing techniques are assessed for this(e.g.,down-sampling,averaging,fast Fourier transforms(FFTs),histograms).Next,fresh,unseen AE data is given to the trained model and the resulting friction predictions are compared with the directly measured *** is excellent agreement between the measured and predicted friction when the GPR model is used on AE histogram data,with root mean square(RMS)errors as low as 0.03 and Pearson correlation coefficients reaching ***,predictions remain accurate despite changes in test conditions such as normal load,reciprocating frequency,and stroke *** paves the way for remote,acoustic measurements of friction in inaccessible locations within machinery to increase mechanical efficiency and avoid costly failure/needless maintenance.

关键词： acoustic emission condition monitoring friction machine learning Gaussian process regression support vector machine

Evaluation of the Shallow Gas Hydrate Production Based on the Radial Drilling-Heat Injection-Back Fill Method

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Journal of Ocean University of China 2024年第1期23卷 119-128页

作者： CHEN Qiang WAN Yizhao WU Nengyou SUN Jianye WANG Jian LIU Changling LI Yanlong LI Chengfeng HU Gaowei Key Laboratory of Gas Hydrate Ministry of Natural ResourcesQingdao 266071China Laboratory for Marine Mineral Resources Laoshan LaboratoryQingdao 266071China CNPC Offshore Engineering company limited Beijing 100028China Technology Innovation Center for Marine Methane Monitoring Ministry of Natural ResourcesQingdao 266071China

It has been evidenced that shallow gas hydrate resources are abundant in deep oceans *** geological back-ground,occurrence,and other characteristics differ significantly from deep-seated *** of the high risk of well construction and low production efficiency,they are difficult to be recovered by using conventional oil production *** a result,this paper proposes an alternative design based on a combination of radial drilling,heat injection,and backfilling ***-branch holes are used to penetrate shallow gas hydrate reservoirs to expand the depressurization area,and heat injection is utilized as a supplement to improve gas *** information collected from an investigation site close to the offshore production well in the south China Sea is used to assess the essential components of this plan,including well construction stability and gas production *** demonstrates that the hydraulic fracturing of the 60mbsf overburden layer can be prevented by regulating the drilling fluid ***,the traditional well structure is unstable,and the suction anchor is advised for better mechanical *** gas produc-tion rate can be significantly increased by combining hot water injection and depressurization ***,the suitable produc-tion equipment already in use is discussed.

关键词： shallow gas hydrate trail production radial drilling-heat injection-back fill method experimental and numerical simulation

Wetting-drying effect on the strength and microstructure of cementphosphogypsum stabilized soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1049-1058页

作者： Lingling Zeng Xia Bian Jiaxing Weng Tao Zhang College of Civil Engineering Zhejiang University of TechnologyHanzhou310014China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China Jiangsu Water Source company Ltd.of the Eastern Route of the south-to-North Water Diversion Project Nanjing210000China Power China Zhongnan Engineering Corporation limited Changsha410027China

Phosphogypsum has often been used as an effective and environmentally friendly binder for partial replacement of cement,improving the engineering properties of slurries with high water ***,the influence of phosphogypsum on the physicomechnical properties of stabilized soil subjected to wettingedrying cycles is not well understood to *** this study,the effect of phosphogypsum on the durability of stabilized soil was studied by conducting a series of laboratory experiments,illustrating the changes in mass loss,pH value and unconfined compressive strength(qu)with wettingdrying *** test results showed that the presence of phosphogypsum significantly restrained the mass loss in the early stage(lower than the 4th cycle),which in turn led to a higher qu of stabilized soil than that without *** the 4th cycle,a sudden increase in mass loss was observed for stabilized soil with phosphogypsum,resulting in a significant drop in qu to a value lower than those without phosphogypsum at the 6th *** addition,the qu of stabilized soils correlated well with the measured soil pH irrespective of phosphogypsum content for all wettingedrying *** to the microstructure observation via scanning electron microscope(SEM)and X-ray diffraction(XRD)tests,the mechanisms relating the sudden loss of qu for the stabilized soils with phosphogypsum after the 4th wetting-drying cycle are summarized as follows:(i)the disappearance of ettringite weakening the cementation bonding effect,(ii)the generation of a larger extent of microcrack,and(iii)a lower pH value,in comparison with the stabilized soil without phosphogypsum.

关键词： Wetting-drying Phosphogypsum Microstructure Durability

Recent advancements in hydrometallurgical recycling technologies of spent lithium-ion battery cathode materials

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Rare Metals 2024年第3期43卷 879-899页

作者： Juan Wu Li Xiao Li Shen Jian-Jun Ran Hui Zhong Yi-Rong Zhu Han Chen College of Materials and Advanced Manufacturing Hunan University of TechnologyZhuzhou412007China School of Resources Processing and Bioengineering Central South UniversityChangsha410083China Guangdong JiaNa Energy Technology company Qingyuan513000China

The rapidly increasing production of lithium-ion batteries(LIBs)and their limited service time increases the number of spent LIBs,eventually causing serious environmental issues and resource *** the perspectives of clean production and the development of the LIB industry,the effective recovery and recycling of spent LIBs require urgent *** study provides an overview of the current hydrometallurgical processes employed in the recycling of spent cathode materials,focusing on the leaching of valuable metals and their *** particular,this research reviews the various leaching systems(inorganic acid,organic acid,and ammonia)and the separation of valuable metals,and then,recommendations for subsequent study are offered in an attempt to contribute to the development of highly efficient methods for recycling spent cathode *** addition,a range of existing technologies,such as solvent extraction,chemical precipitation,electrochemical deposition,and regeneration,for the postprocessing of leaching solutions are ***,the promising technologies,existing challenges and suggestions with respect to the development of effective and environmentally friendly recycling methods for handling spent cathode materials are identified.

关键词： Spent lithium-ion batteries(LIBs) Cathode material Hydrometallurgy Leaching Recycling

Trajectory optimisation in electrical discharge machining of three-dimensional curved and twisted channels

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Chinese Journal of Aeronautics 2022年第4期35卷 473-484页

作者： Jianshe ZHAO Yicong QIU Jian YUAN Chao LIU College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Laboratory of Integrated Electrical Processing Nanjing HANGPU Machinery Technology Company LimitedNanjing 210000China Military Representative Bureau of the Air Force Equipment Department in Shanghai and Military Representative Office in Zhuzhou Region Zhuzhou 412002China aecc south industry company limited Zhuzhou 412002China

Numerical control electrical discharge machining(NC EDM) is one of the most widely used machining technologies for manufacturing a closed blisk flow path, particularly for three-dimensional(3D) curved and twisted flow channels. In this process, tool electrode design and machining trajectory planning are the key factors affecting machining accessibility and efficiency. Herein, to reduce the difficulty in designing the electrode and its motion path in the closed curved and twisted channels, a heuristic search hybrid optimisation strategy based on channel grids is adopted to realise the initial electrode trajectory design search and optimised size reduction. By transferring the trajectory optimisation constraints from the complex free-form surface to numbered grids, the search is found to be more orderly and accurate. The two trajectory indicators, namely argument angle and minimum distance, are analysed separately for the optimised results of the adaptive learning particle swarm optimisation algorithm, demonstrating that they can meet the actual processing *** results of NC EDM indicate that the motion path generated by this design method can meet the machining requirements of 3D curved and twisted flow channels.

关键词： Blisk Electrical discharge machining(EDM) Electrode Objective functions Trajectory generation

Sealing performance analysis of rubber core of annular BOP:FEM simulation and optimization to prevent the SBZ

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Petroleum 2023年第3期9卷 419-426页

作者： Liangliang Dong Yuan Tang Geng Tang Hai Li Ke Wu Wei Luo School of Mechanical and Electrical Engineering Southwest Petroleum University610500ChengduChina Engineering Technology Research Institute of southwest Oil&Gas Field company 618300DeyangChina aecc south industry company limited Zhuzhou412002China Sichuan Shengnuo Oil&Gas Engineering Technology Service Co. Ltd.618000DeyangChina

The present work studies the influence of oil pipe joint passing through annular blowout preventer(BOP)on its sealing performance in high pressure gas wells under snubbing *** the oil pipe joint passes through the BOP,due to the change of its structure,it is easy to cause the rubber core seal failure of the BOP,resulting in the leakage of toxic and harmful gas in the well,which seriously threatens the safety of the *** at the problem of gas leakage caused by rubber core seal failure of annular BOP,based on the rubber large deformation theory and rubber core seal mechanism,a dynamic finite element model of rubber core-oil pipe joint is established,and the correctness of the model is verified by comparing the failure of rubber core on site;The results show that when the oil pipe joint passes through the BOP,a sealing buffer zone(SBZ)will be formed at the upper and lower shoulder of the joint,and the contact stress of the rubber core will decrease by 10 MPae30 MPa;Because of the funnel effect of the rubber core,the damage of the rubber core caused by the running oil pipe joint of the BOP is greater than that caused by the lift oil pipe joint;When lifting oil pipe,the existence of SBZ is easy to cause gas leakage in the well;The optimized structure of oil pipe joint with small inclination and long shoulder can significantly reduce the influence of SBZ on the sealing performance of *** research work in this paper is of great significance to improve the dynamic sealing performance of BOP.

关键词： Annular blowout preventer Hyperelasticity Sealing performance Structural optimization FEM

A tip clearance prediction model for multistage rotors and stators in aero-engines

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Chinese Journal of Aeronautics 2021年第2期34卷 343-357页

作者： Huibin SUN Jing WANG Kai CHEN Huateng XIA Xin FENG Zhiyong CHANG Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Poly technical UniversityXi'an 710072China aecc south industry company limited Zhuzhou 412002China

Tip clearances of multistage rotors and stators greatly affect aero-engines’ aerodynamic efficiency, stability and safety. The inevitable machining and assembly errors, as well as the complicated error propagation mechanism, cause overproof or non-uniform tip clearances. However, it is generally accepted that tip clearances are difficult to predict, even under assembly state. In this paper, a tip clearance prediction model is proposed based on measured error data. Some 3 D error propagation sub-models, regarding rotors, supports and casings, are built and combined. The complex error coupling relationship is uncovered using mathematical methods. Rotor and stator tip clearances are predicted and analyzed in different phase angles. The maximum, minimum and average tip clearances can be calculated. The proposed model is implemented by a computer program,and a case study illustrates its performance and verifies its feasibility. The results can be referred by engineers in assembly quality judgement and decision-making.

关键词： Tip clearance Prediction Error propagation model Rotor and stator Aero-engine Assembly

Microstructure and mechanical properties of a low activation cast WTaHfTiZr refractory high-entropy alloy

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China Foundry 2022年第6期19卷 489-494页

作者： Xian-neng Ma Yi-fei Hu Kai Wang Hai-long Zhang Zi-tian Fan Jin-ping Suo Xin-wang Liu State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Dekai Intelligent Casting Co. Ltd.Zhuozhou 072750HebeiChina China Iron and Steel Research Institute Group Beijing 100081China aecc south industry company limited Zhuzhou 412002HunanChina

In the face of the requirement that nuclear fusion reactor materials exhibit more excellent thermal,mechanical and physical properties,a novel refractory highentropy alloy,WTaHfTiZr was *** constituent elements were selected in consideration of low activation,high melting point and high *** alloys were prepared by arc *** as-cast alloy shows a dendrite microstructure with two disordered BCC phases,which caused by the preferential nucleation of W and Ta with much higher melting points during *** exhibits a high compressive yield strength of 1,900 MPa and fracture strain of 8.1% at room temperature,and its yield strengths are up to 612 MPa at 700 ℃ and 203 MPa at 1,000 ℃,*** high strengths are attributed mainly to solid solution strengthening and second phase *** alloy shows great promise as one of the next-generation nuclear fusion reactor materials.

关键词： refractory high-entropy alloy phase structure microstructure mechanical properties