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Effects of Floating Ring Bearing Manufacturing Tolerance Clearances on the Dynamic Characteristics for Turbocharger

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Chinese Journal of Mechanical Engineering 2015年第3期28卷 530-540页

作者： WANG Longkai BIN Guangfu LI Xuejun ZHANG Xuefeng Health Maintenance for Mechanical equipment Key Lab of Hunan Province Hunan University of Science and Technology Xeca Turbo Technologies(Beijing) co. Ltd.

The inner and outer oil film dynamic characteristic co.fficients of floating ring bearings（FRBs） change due to the manufacturing tolerance of the floating ring, journal and intermediate, which leads to high-speed turbocharger＇s vibration too large and even causes nonlinear vibration accident. However, the investigation of floating ring bearing manufacturing tolerance clearance on the rotordynamic characteristics is less at present. In order to study the influence law of inner and outer clearance on turbocharger vibration, the rotor dynamic motion equations of turbocharger supported in FRBs are derived by analyzing the size relations between floating ring, journal and intermediate for the inner and outer oil film clearances, the time transient response analysis for co.bination of FRBs clearance are developed. A realistic turbocharger is taken as a research object, the FE model of the turbocharger with FRBs is modeled. Under the co.ditions of four kinds of limit state bearing clearances for inner and outer oil film, the nonlinear transient analyses are performed based on the established FE dynamic models of the nonlinear rotor-FRBs system applied incentive co.binations of gravity and unbalance force, respectively. From the waterfall, the simulation results show that the speed for the appearance of fractional frequency is not identical and the amplitude magnitude is different under the four kinds of bearing manufacturing tolerance limit clearances, and fractional frequency does not appear in the turbocharger and the amplitude is minimum under the ODMin/IDMax bearing manufacturing tolerance clearances. The turbocharger vibration is reduced by co.trolling the manufacturing tolerance clearance co.binations of FRBs, which is helpful for the dynamic design and production-manufacturing of high-speed turbocharger.

关键词： turbocharger floating ring bearing manufacturing tolerance clearance nonlinear transient analysis dynamic characteristics

co.st-Down Modeling of Canned Motor Based on Torque Behavior Study

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Journal of Shanghai Jiaotong university(Science) 2015年第4期20卷 420-426页

作者：薛亚波姚振强成德沈洪李孟超 School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China State Key Laboratory of Mechanical system and Vibration Shanghai 200240 China Harbin Electric Power equipment co. Ltd. Harbin 150040 China

The co.st-down behavior is specially designed to satisfy the certain flow requirements in a special kind of canned motor pump when it is used in primary reactor co.lant system. However, co.st-down models once used are not suitable for designing ultra-large canned motor pumps with flywheels, in which case rotor's fluid resistance of canned motor is modeled by an empirical co.stant. When the size of canned motor increases, the error of empirical relationship beco.es remarkable. In thrall to material's density and strength, flow resistance of co.st-down behavior should be dynamically modeled accurately to reduce the demands of materials. In this paper, an improved analytical model is proposed to study barbell-like canned motor's co.st-down characteristic based on basic torque behavior researches in Taylor-co.ette flow and hydraulic co.pler, where bearing's resistance is ignored. This model takes geometric and kinematic parameters into co.sideration. In addition, the influence of pressure and temperature is co.pled into this co.st-down model by using Reolands' visco.ity *** on this model, co.st-down behavior is studied and parameters sensitivity analysis is co.ducted from design view point. Parameters sensitivity analysis indicates that the density and distribution of materials have more remarkable influence on co.st-down behavior co.pared with working co.dition and geometric parameters.

关键词： canned motor pump co.st-down behavior Taylor-co.ette(TC) flow torque behavior theoretical model

Optimization for Micro-energy Grid Dispatch Based on Non-supplementary Fired co.pressed Air Energy Storage Aided Energy Hub and Hybrid Hyper-spherical Search

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Journal of Modern Power systems and Clean Energy 2022年第4期10卷 1009-1020页

作者： Zhenlong Li Peng Li Jing Xia Xiangqian Liu Beijing Jiaotong University BeijingChina State Key Laboratory of Alternate Electrical Power system with Renewable Energy Sources North China Electric Power UniversityBeijingChina Beijing Goldwind Science&Creation Wind Power equipment co. Ltd.BeijingChina

Micro-energy grids have shown superiorities over traditional electricity and heating management *** paper presents a hybrid optimization strategy for micro-energy grid dispatch with three salient ***,to enhance the ability to support new storage equipment,an energy hub model is proposed using the non-supplementary fired co.pressed air energy storage(NSF-CAES).This provides flexible dispatch for co.ling,heating and ***,co.sidering the unique characteristics of the NSF-CAES,a sliding time window(STW)method is designed for simple but effective energy ***,for the optimization of energy dispatch,we blend the differential evolution(DE)with the hyper-spherical search(HSS)to formulate a hybrid DE-HSS algorithm,which enhances the global search ability and *** case studies are performed using real data of scenarios to demonstrate the superiorities of the proposed scheme.

关键词： Energy hub dispatch hyper-spherical search micro-energy grid sliding time window

High precision 3D reco.struction system based on PTZ image acquisition device

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High precision 3D reconstruction system based on PTZ image a...

第35届中国过程控制会议

作者： Changdi Li Jian Ding Wenhan Ji Yichen Song Anqi Xie Minze Wang Qunshan He Xinggao Liu School of Biotechnology Jiangnan University Suzhou Hanyun Keling Network Information Service co. Ltd. School of Advanced Technology Xi'an Jiaotong-Liverpool University

In the era of digital intelligence, the co.cept of 3D reco.struction has progressively evolved and garnered significant interest. co.sequently, there is a need to establish a high-precision, low-co.t, and high-efficiency 3D reco.struction system for the digital twin. In this paper, we introduce our 3D reco.struction system and the Pan-Tilt-Zoom(PTZ) image acquisition equipment suitable for this system. Furthermore, we have specifically designed single-node and multi-node pose optimization algorithms for this system to enhance the accuracy of 3D reco.struction. Through extensive experimentation, we demonstrate that our proposed 3D reco.struction system,based on the PTZ image acquisition device, can obtain high-precision 3D reco.struction models. This provides a solid foundation for the digital twin.

关键词： PTZ image acquisition device 3D reco.struction Pose optimization Digital twin

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中国碳收支:1980~2021年

Science Bulletin 2024年第1期69卷 114-124页

作者：夏晓圣任培阳王旭辉刘丹陈修治丹利何斌何洪林居为民梁敏琪陆星劼彭静覃章才夏江周郑博魏静乐旭于贵瑞朴世龙袁文平 School of atmospheric Sciences Guangdong Province Data Center of Terrestrial and Marine Ecosystems Carbon CycleSun Yat-sen UniversityZhuhai 510245China Sino-French Institute for Earth system Science College of Urban and Environmental SciencesPeking UniversityBeijing 100091China State Key Laboratory of Tibetan Plateau Earth system Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Earth Surface Processes and Resource Eco.ogy College of Global Change and Earth System ScienceBeijing Normal UniversityBeijing 100875China Synthesis Research Center of China’s Eco.0} Research Network Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China International Institute for Earth system Science Nanjing UniversityNanjing 210023China Tianjin Key Laboratory of Water Resources and Environment Tianjin Normal UniversityTianjin 300387China Institute of Environment and Eco.ogy Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Jiangsu Key Laboratory of atmospheric Environment Monitoring and Pollution co.trol Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China

As one of the world's largest emitters of greenhouse gases,China has set itself the ambitious goal of achieving carbon peaking and carbon ***,it is crucial to quantify the magnitude and trend of sources and sinks of atmospheric carbon dioxide(co.(2)),and to monitor China's progress toward these *** state-of-the-art datasets and models,this study co.prehensively estimated the anthropogenic co.(2)emissions from energy,industrial processes and product use,and waste along with natural sources and sinks of co.(2)for all of China during *** reco.nize the differences among various methods of estimating greenhouse emissions,the estimates are co.pared with China's National Greenhouse Gas Inventories(NGHGIs)for 1994,2005,2010,2012,and *** co.(2)emissions in China have increased by 7.39 times from 1980 to 12.77 Gt co.(2)a^(-1)in *** benefiting from eco.ogical projects(e.g.,Three Norths Shelter Forest system Project),the land carbon sink in China has reached 1.65 Gt co.(2)a^(-1)averaged through 2010-2021,which is almost 15.81 times that of the carbon sink in the *** average,China's terrestrial eco.1}s offset 14.69%±2.49%of anthropogenic co.(2)emissions through *** provincial-level administrative regions of China,Xizang and Qinghai,have achieved carbon neutrality acco.ding to our estimates,but nearly half of the administrative regions of China have terrestrial carbon sink offsets of less than 10%of anthropogenic co.(2)*** study indicated a high level of co.sistency between NGHGIs and various datasets used for estimating fossil co.(2)emissions,but found notable differences for land carbon *** estimates of the terrestrial carbon sinks of NGHGIs urgently need to be verified with process-based models which integrate the co.prehensive carbon cycle processes.

关键词： co.(2)emission Land carbon sink China Carbon neutrality Carbon budget

co.struction and Optimization of Liquefied Natural Gas Regasification co.d Energy co.prehensive Utilization system on Floating Storage Regasification Unit

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Journal of Thermal Science 2022年第6期31卷 1853-1867页

作者： YAO Shouguang WANG Mengdi YAN Likun ZHANG Qiang YE Yong School of Energy and Power Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China China Ship Shenghui equipment co. LtdZhangjiagang 215600China

In this paper, the efficient utilization of liquefied natural gas(LNG) vaporization co.d energy in offshore liquefied natural gas floating storage regasification unit(FSRU) is studied. On the basis of co.sidering different boil-off gas(BOG) practical treatment processes, a cascade co.prehensive utilization scheme of co.d energy of LNG based on the longitudinal three-stage organic Rankine cycle power generation and the low-grade co.d energy used to frozen seawater desalination was proposed. Through the co.parative analysis of the effects of the pure working fluid and eight mixed working fluids on the performance of the new system, the co.bination scheme of system mixed working fluid with the highest exergy efficiency of the system was determined. Then, the genetic algorithm was used to optimize the parameters of the new system. After optimization, the net output power of the LNG co.d energy co.prehensive utilization system proposed in this paper was 5186 kW, and the exergy efficiency is 30.6%. co.sidering the power generation and freshwater revenue, the annual eco.omic benefit of the system operating is 18.71 million CNY.

关键词： LNG co.d energy utilization mixed working fluid organic Rankine cycle boil-off gas(BOG)treatment

Online soft measurement for wastewater treatment system based on hybrid deep learning

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 77-89页

作者： Wenjie Mai Zhenguo Chen Xiaoyong Li Xiaohui Yi Yingzhong Zhao Xinzhong He Xiang Xu Mingzhi Huang SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSchool of EnvironmentSouth China Normal UniversityGuangzhou 510006China Fujian Environmental Protection Design Institute co.Ltd. Fuzhou 350000China Huashi(Fujian)Environment Technology co.Ltd. Quanzhou362001China SCNU Qingyuan Institute of Science and Technology Innovation co.Ltd. Qingyuan 511517China Eco. Technology co.Ltd. Yantai 265503China

The existing automated wastewater treatment co.trol systems enco.nter challenges such as the utilization of specialized testing instruments, equipment repair co.plications, high operational co.ts, substantial operational errors, and low detection accuracy. An effective soft measure model offers a viable approach for real-time monitoring and the development of automated co.trol in the wastewater treatment process. co.sequently, a novel hybrid deep learning CNN-BNLSTM-Attention (CBNLSMA) model, which inco.porates co.volutional neural networks (CNN), bidirectional nested long and short-term memory neural networks (BNLSTM), attention mechanisms (AM), and Tree-structure Parzen Estimators (TPE), has been developed for monitoring effluent water quality during the wastewater treatment process. The CBNLSMA model is divided into four stages: the CNN module for feature extraction and data filtering to expedite operations;the BNLSTM module for temporal data’s temporal information extraction;the AM module for model weight reassignment;and the TPE optimization algorithm for the CBNLSMA model’s hyperparameter search optimization. In co.parison with other models (TPE-CNN-BNLSTM, TPE-BNLSTM-AM, TPE-CNN-AM, PSO-CBNLSTMA), the CBNLSMA model reduced the RMSE for effluent co. prediction by 25.4%, decreased the MAPE by 32.9%, and enhanced the R2 by 14.9%. For the effluent SS prediction, the CBNLSMA model reduced the RMSE by 26.4%, the MAPE by 21.0%, and improved the R2 by 35.7% co.pared to other models. The simulation results demonstrate that the proposed CBNLSMA model holds significant potential for real-time effluent quality monitoring, indicating its high potential for automated co.trol in wastewater treatment processes.

关键词： Prediction model Soft measurement CNN-BNLSTM-AM model TPE optimization algorithm

Iterative-Reweighting-Based Robust Iterative-Closest-Point Method

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Journal of Shanghai Jiaotong university(Science) 2021年第5期26卷 739-746页

作者： ZHANG Jianlin ZHOU Xuejun YANG Ming Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of system co.trol and Information Processing of Ministry of Education Shanghai 200240China Noblelift Intelligent equipment co. Ltd.Huzhou 313100ZhejiangChina

In point cloud registration applications,noise and poor initial co.ditions lead to many false *** matches significantly degrade registration accuracy and speed.A penalty function is adopted in many robust point-to-point registration methods to suppress the influence of false ***,after applying a penalty function,problems cannot be solved in their analytical forms based on the introduction of ***,most existing methods adopt the descending *** this paper,a novel iterative-reweighting-based method is proposed to overco.e the limitations of existing *** proposed method iteratively solves the eigenvectors of a four-dimensional matrix,whereas the calculation of the descending method relies on solving an eight-dimensional ***,the proposed method can achieve increased co.putational *** proposed method was validated on simulated noise co.ruption data,and the results reveal that it obtains higher efficiency and precision than existing methods,particularly under very noisy *** results for the KITTI dataset demonstrate that the proposed method can be used in real-time localization processes with high accuracy and good efficiency.

关键词： point cloud registration iterative reweighting iterative closest-point(ICP) robust localization

Characteristics of motorized spindle supported by active magnetic bearings

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Chinese Journal of Aeronautics 2014年第6期27卷 1619-1624页

作者： Xie Zhenyu Yu Kun Wen Liantang Wang Xiao Zhou Hongkai Department of Design Engineering Nanjing University of Aeronautics and Astronautics Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Jiangxi Zhonghang Optics equipment co. Ltd.

A motorized spindle supported by active magnetic bearings（AMBs） is generally used for ultra-high-speed machining. Iron loss of radial AMB is very great owing to high rotation speed, and it will cause severe thermal deformation. The problem is particularly serious on the occasion of large power application, such as all electric aero-engine. In this study, a prototype motorized spindle supported by five degree-of-freedom AMBs is developed. Homopolar and heteropolar AMBs are independently adopted as radial bearings. The influences of the two types of radial AMBs on the dynamic characteristics of the motorized spindle are co.paratively investigated by theoretical analysis, test modal analysis and actual operation of the system. The iron loss of the two types of radial AMBs is analyzed by finite element software and verified through run-down experiments of the system. The results show that the structures of AMB have less influence on the dynamic characteristics of the motorized spindle. However, the homopolar structure can effectively reduce the iron loss of the radial AMB and it is useful for improving the overall performance of the motorized spindle.

关键词： Dynamic characteristics Finite element analysis Loss Magnetic bearings Modal analysis Spindle design