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Machine learning in materials design:Algorithm and application

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Chinese Physics B 2020年第11期29卷 52-80页

作者：宋志龙陈曦雯孟繁斌程观剑王陈孙中体尹万健 College of energy Soochow Institute for Energy and Materials InnovationS(SIEMIS)and Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySuzhou 215006China

Traditional materials discovery is in ‘trial-and-error’ mode, leading to the issues of low-efficiency, high-cost, and unsustainability in materials design. Meanwhile, numerous experimental and computational trials accumulate enormous quantities of data with multi-dimensionality and complexity, which might bury critical ‘structure–properties’ rules yet unfortunately not well explored. Machine learning(ML), as a burgeoning approach in materials science, may dig out the hidden structure–properties relationship from materials bigdata, therefore, has recently garnered much attention in materials science. In this review, we try to shortly summarize recent research progress in this field, following the ML paradigm:(i) data acquisition →(ii) feature engineering →(iii) algorithm →(iv) ML model →(v) model evaluation →(vi) application. In section of application, we summarize recent work by following the ‘material science tetrahedron’:(i) structure and composition →(ii) property →(iii) synthesis →(iv) characterization, in order to reveal the quantitative structure–property relationship and provide inverse design countermeasures. In addition, the concurrent challenges encompassing data quality and quantity, model interpretability and generalizability, have also been discussed. This review intends to provide a preliminary overview of ML from basic algorithms to applications.

关键词： machine learning materials design structure–property relationship active learning

Effect of system response on partial surge initiated instability in a transonic axial flow compressor

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Chinese Journal of Aeronautics 2022年第2期35卷 117-127页

作者： Tianyu PAN Zhaoqi YAN Dakun SUN Simin LI Mengzong ZHENG Qiushi LI Reserach institute of Aero-Engine Beihang UniversityBeijing 100083China School of energy and Power Engineering Beihang UniversityBeijing 100083China Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

Partial surge is a type of instability inception in transonic compressors and occurs in the form of axisymmetric low-frequency disturbances localized in the hub region.Previous studies illustrate that the frequency of partial surge is set by the Helmholtz frequency of the entire system,which motivates to propose a hypothesis that the system response performs an important role in the formation of partial surge.For further verification,a series of experiments are conducted to explore the link between the propagating of the partial surge and the system feedback in this study.In the first case,an additional test point is set on the wall of the plenum to detect the system response.Combining the flow behaviors inside the plenum with the disturbances in the rotor tip and stator hub/tip regions,the effects of the system feedback on the occurrence of the continuous disturbances and the rotating stall cells are illustrated.In the second case,a screen is mounted at the compressor outlet to prevent positive feedback from the plenum.The experimental results demonstrate that in the absence of system feedback,it is the occurrence of spike-type stall inception that leads to the flow instability instead of that of partial surge.In addition,three flow phenomena in the second case are discussed,including the occurrence of the single pulse,the unstable process during the stall evolution and the switch of instability inception.

关键词： Partial surge Plenum amplification Rotating stall System response Stall inception Transonic compressor

Influence of structure and material on the vibration modal characteristics of novel combined flexible road wheel

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Defence Technology（防务技术） 2022年第7期18卷 1179-1189页

作者： Yao-ji Deng You-qun Zhao Fen Lin Li-guo Zang College of Mechanical Engineering Yangzhou UniversityYangzhou 225127China College of energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Automobile&Rail Transit Nanjing Institute of TechnologyNanjing 211167China

Aiming at the independent development of tracked vehicles,it is urgent to improve its mobility,passability and ride comfort,a new type of flexible road wheel with a“wheel-hinge-hub”combined structure is proposed in this study.The vibration model characteristics of the flexible road wheel were studied by the combination of numerical simulation and experiments.The superelasticity of rubber is obtained through uniaxial tensile experiment of the material and a detail three-dimensional nolinear finite element model of the flexible road wheel is established through finite element software ABAQUS.The free vibration equation of the flexible road wheel is solved by Lanczos vector direct superposition method,and its predicted modes and natural frequencies are compared with experimental results,which verifies the accuracy and reliability of the established finite element model.On this basis,the effects of various key structural or material factors on the natural frequencies of the flexible road wheel are studied using orthogonal experimental design method.Besides,the vibration modal characteristics of the flexible road wheel are also compared with those of the rigid road wheel.The research results provide a theoretical basis for the vibration and noise reduction of flexible road wheel.

关键词： Flexible road wheel Orthogonal experimental design Vibration modal Tracked vehicle Finite element analysis

Multi-dimensional hybrid flexible films promote uniform lithium deposition and mitigate volume change as lithium metal anodes

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Journal of energy Chemistry 2022年第2期31卷 583-591页

作者： Jian Yang Tingting Feng Junming Hou Xinran Li Boyu Chen Cheng Chen Zhi Chen Yaochen Song Mengqiang Wu School of Materials and energy University of Electronic Science and Technology of Chin1Chengdu 611731SichuanChina Yangtze Delta Region institute(HuZhou) University of Electronic Science and Technology of Chin1Huzhou 313001ZhejiangChina

Lithium metal is the ultimate anode material for next-generation high-energy batteries.Yet,the practical application of lithium metal anodes is limited by the formation of Li dendrites and large volume changes.Herein,an effective multi-dimensional hybrid flexible film(MD-HFF)composed of iodine ion(0 dimension),CNTs(1 dimension)and graphene(2 dimensions)is designed for regulating Li deposition and mitigating volume changes.The multi-dimensional components serve separate roles:(1)iodine ion enhances the conductivity of the electrode and provides lithiophilic sites,(2)CNTs strengthen interlaminar conductance and mechanical strength,acting as a spring in the layered structure to alleviate volume changes during Li plating and stripping and(3)graphene provides mechanical flexibility and electrical conductivity.The resulting MD-HFF material supports stable Li plating/stripping and high Coulombic efficiency(99%)over 230 cycles at 1 mA cm^(-2) with a deposition capacity of 1 mAh cm^(-2).Theoretical calculations indicate that LiI contributes to the lateral growth of Li on the MD-HFF surface,thereby inhibiting the formation of Li dendrites.When paired with a typical NCM811 cathode,the assembled MD-HFF‖NCM811 cell exhibit improved capability and stable cycling performance.This research serves to guide material design in achieving Li anode materials that do not suffer from dendrite formation and volume changes.

关键词： Flexible film Li metal anode Uniform Li deposition Electrode volume change

Vibration of fluid-conveying pipe with nonlinear supports at both ends

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Applied Mathematics and Mechanics(English Edition) 2022年第6期43卷 845-862页

作者： Sha WEI Xiong YAN Xin FAN Xiaoye MAO Hu DING Liqun CHEN Shanghai institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Engineering Science University of Science and Technology of ChinaHefei 230026China

The axial fluid-induced vibration of pipes is very widespread in engineering applications.The nonlinear forced vibration of a viscoelastic fluid-conveying pipe with nonlinear supports at both ends is investigated.The multi-scale method combined with the modal revision method is formulated for the fluid-conveying pipe system with nonlinear boundary conditions.The governing equations and the nonlinear boundary conditions are rescaled simultaneously as linear inhomogeneous equations and linear inhomogeneous boundary conditions on different time-scales.The modal revision method is used to transform the linear inhomogeneous boundary problem into a linear homogeneous boundary problem.The differential quadrature element method(DQEM)is used to verify the approximate analytical results.The results show good agreement between these two methods.A detailed analysis of the boundary nonlinearity is also presented.The obtained results demonstrate that the boundary nonlinearities have a significant effect on the dynamic characteristics of the fluid-conveying pipe,and can lead to significant differences in the dynamic responses of the pipe system.

关键词： gyroscopic system fluid-conveying pipe transverse vibration nonlinear boundary

An anomaly detection method for spacecraft solar arrays based on the ILS-SVM model

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系统工程与电子技术：英文版 2023年第2期34卷 515-529页

作者： WANG Yu ZHANG Tao HUI Jianjiang LIU Yajie College of Systems Engineering National University of Defense TechnologyChangsha 410073China Hunan Key Laboratory of Multi-energy System Intelligent Interconnection Technology Changsha 410073China Beijing institute of Tracking and Telecommunication Technology Beijing 100094China

Solar arrays are important and indispensable parts of spacecraft and provide energy support for spacecraft to operate in orbit and complete on-orbit missions.When a spacecraft is in orbit,because the solar array is exposed to the harsh space environment,with increasing working time,the performance of its internal electronic components gradually degrade until abnormal damage occurs.This damage makes solar array power generation unable to fully meet the energy demand of a spacecraft.Therefore,timely and accurate detection of solar array anomalies is of great significance for the on-orbit operation and maintenance management of spacecraft.In this paper,we propose an anomaly detection method for spacecraft solar arrays based on the integrated least squares support vector machine(ILS-SVM)model:it selects correlated telemetry data from spacecraft solar arrays to form a training set and extracts n groups of training subsets from this set,then gets n corresponding least squares support vector machine(LS-SVM)submodels by training on these training subsets,respectively;after that,the ILS-SVM model is obtained by integrating these submodels through a weighting operation to increase the prediction accuracy and so on;finally,based on the obtained ILS-SVM model,a parameterfree and unsupervised anomaly determination method is proposed to detect the health status of solar arrays.We use the telemetry data set from a satellite in orbit to carry out experimental verification and find that the proposed method can diagnose solar array anomalies in time and can capture the signs before a solar array anomaly occurs,which reflects the applicability of the method.

关键词： spacecraft solar array anomaly detection integrated least squares support vector machine(ILS-SVM) induced ordered weighted average(IOWA)operator integrated model

The inactivation of bacteriophages MS2 and PhiX174 by nanoscale zero-valent iron:Resistance difference and mechanisms

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Frontiers of Environmental Science & Engineering 2022年第8期16卷 247-256页

作者： Rong Cheng Yingying Zhang Tao Zhang Feng Hou Xiaoxin Cao Lei Shi Peiwen Jiang Xiang Zheng Jianlong Wang School of Environment and Natural Resources Renmin University of ChinaBeijing 100872China China Water Environment Group Co.Ltd. Beijing 101101China institute of Nuclear and New energy Technology Tsinghua UniversityBeijing 100084China

Pathogenic enteric viruses pose a significant risk to human health.Nanoscale zero-valent iron(nZVI),a novel material for environmental remediation,has been shown to be a promising tool for disinfection.However,the existing research has typically utilized MS2 or f2 bacteriophages to investigate the antimicrobial properties of nZVI,and the resistance difference between bacteriophages,which is important for the application of disinfection technologies,is not yet understood.Here,MS2 and PhiX174 containing RNA and DNA,respectively,were used as model viruses to investigate the resistances to nZVI.The bacteriophage inactivation mechanisms were also discussed using TEM images,protein,and nucleic acid analysis.The results showed that an initial concentration of 10^(6)PFU/mL of MS2 could be completely inactivated within 240 min by 40 mg/L nZVI at pH 7,whereas the complete inactivation of PhiX174 could not be achieved by extending the reaction time,increasing the nZVI dosage,or changing the dosing means.This indicates that the resistance of phage PhiX174 to nZVI was much stronger than that of MS2.TEM images indicated that the viral particle shape was distorted,and the capsid shell was ruptured by nZVI.The damage to viral surface proteins in both phages was examined by three-dimensional fluorescence spectrum and sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE).However,the nucleic acid analysis demonstrated that the nucleic acid of MS2,but not PhiX174,was destroyed.It indicated that bacteriophage inactivation was mainly attributed to the damage of nucleic acids.

关键词： Nanoscale zero-valent iron(nZVI) MS2 PhiΧ174 Resistance Inactivation Pathogenic microorganisms

Large-eddy simulation of turbulent boundary layer flow over multiple hills

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Journal of Hydrodynamics 2023年第4期35卷 746-756页

作者： Ying Deng Kai Leong Chong Yan Li Zhi-ming Lu Bo-fu Wang Shanghai Key Laboratory of Mechanics in energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

Atmospheric boundary layer(ABL)flow over multiple-hill terrain is studied numerically.The spectral vanishing viscosity(SVV)method is employed for implicit large eddy simulation(ILES).ABL flow over one hill,double hills,and three hills are presented in detail.The instantaneous three-dimensional vortex structures,mean velocity,and turbulence intensity in mainstream and vertical directions around the hills are investigated to reveal the main properties of this turbulent flow.During the flow evolution downstream,the Kelvin-Helmholtz vortex,braid vortex,and hairpin vortex are observed sequentially.The turbulence intensity is enhanced around crests and reduced in the recirculation zones.The present results are helpful for understanding the impact of topography on the turbulent flow.The findings can be useful in various fields,such as wind energy,air pollution,and weather forecasting.

关键词： Large-eddy simulation(LES) atmospheric boundary layer(ABL)flow complex terrain turbulent flow fields

Coordinated voltage control of renewable energy power plants in weak sending-end power grid

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Global energy Interconnection 2020年第4期3卷 365-374页

作者： Yongning Chi Weihao Li Qiuwei Wu Chao Liu Department of renewable energy China Electric Power Research InstituteBeijing 100031P.R.China School of Electrical Engineering Shandong UniversityJinan 250000P.R.China Center for Electric Power and energy Department of Electrical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark

The utilization of renewable energy in sending-end power grids is increasing rapidly,which brings difficulties to voltage control.This paper proposes a coordinated voltage control strategy based on model predictive control(MPC)for the renewable energy power plants of wind and solar power connected to a weak sending-end power grid(WSPG).Wind turbine generators(WTGs),photovoltaic arrays(PVAs),and a static synchronous compensator are coordinated to maintain voltage within a feasible range during operation.This results in the full use of the reactive power capability of WTGs and PVAs.In addition,the impact of the active power outputs of WTGs and PVAs on voltage control are considered because of the high R/X ratio of a collector system.An analytical method is used for calculating sensitivity coefficients to improve computation efficiency.A renewable energy power plant with 80 WTGs and 20 PVAs connected to a WSPG is used to verify the proposed voltage control strategy.Case studies show that the coordinated voltage control strategy can achieve good voltage control performance,which improves the voltage quality of the entire power plant.

关键词： Coordinated voltage control Model predictive control(MPC) renewable energy Weak sending-end power grid Wind turbine generators(WTGs) Photovoltaic arrays(PVAs) STATCOM