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Phase-field simulations of the effect of temperature and interface for zirconiumδ-hydrides

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Chinese Physics B 2024年第4期33卷 701-710页

作者：陈子航盛杰刘瑜施小明黄厚兵许可王越超武帅孙博刘海风宋海峰 School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Department of Physics University of Science and Technology BeijingBeijing 100083China

Hydride precipitation in zirconium cladding materials can damage their integrity and *** temperature and material defects have a significant effect on the dynamic growth of *** this study,we have developed a phasefield model based on the assumption of elastic behaviour within a specific temperature range(613.K-653.K).This model allows us to study the influence of temperature and interfacial effects on the morphology,stress,and average growth rate of zirconium *** results suggest that changes in temperature and interfacial energy influence the length-to-thickness ratio and average growth rate of the hydride *** ultimate determinant of hydride orientation is the loss of interfacial coherency,primarily induced by interfacial dislocation defects and quantifiable by the mismatch degree *** escalation in interfacial coherency loss leads to a transition of hydride growth from horizontal to vertical,accompanied by the onset of redirection ***,redirection occurs at a critical mismatch level,denoted as qc,and remains unaffected by variations in temperature and interfacial ***,this redirection leads to an increase in the maximum stress,which may influence the direction of hydride crack *** research highlights the importance of interfacial coherency and provides valuable insights into the morphology and growth kinetics of hydrides in zirconium alloys.

关键词： zirconium hydride phase-field method temperature effect mismatch degree

A Composite Ansatz for Calculation of Dynamical Structure Factor

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Chinese Physics Letters 2024年第1期41卷 92-103页

作者：张玉佩莫崇杰张平康炜 HEDPS Center for Applied Physics and Technologyand School of PhysicsPeking UniversityBeijing 100871China beijing Computational Science Research Center Beijing 100193China institute of applied Physics and Computational Mathematics Beijing 100088China HEDPS Center for Applied Physics and Technologyand College of EngineeringPeking UniversityBeijing 100871China

We propose an ansatz without adjustable parameters for the calculation of a dynamical structure *** ansatz combines the quasi-particle Green’s function,especially the contribution from the renormalization factor,and the exchange-correlation kernel from time-dependent density functional theory together,verified for typical metals and semiconductors from a plasmon excitation regime to the Compton scattering *** has the capability to reconcile both small-angle and large-angle inelastic x-ray scattering(IXS)signals with muchimproved accuracy,which can be used as the theoretical base model,in inversely inferring electronic structures of condensed matter from IXS experimental signals *** may also be used to diagnose thermal parameters,such as temperature and density,of dense plasmas in x-ray Thomson scattering experiments.

关键词： excitation inverse verified

Contrast in Secondary Organic Aerosols between the Present Day and the Preindustrial Period:The Importance of Nontraditional Sources and the Changed Atmospheric Oxidation Capability

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Advances in Atmospheric Sciences 2024年第10期41卷 1936-1952,I0002-I0010页

作者： Yingchuan YANG Wenyi YANG Xueshun CHEN Jiawen ZHU Huansheng CHEN Yuanlin WANG Wending WANG Lianfang WEI Ying WEI Qian YE Huiyun DU Zichen WU Zhe WANG Jie LI Xiaodong ZENG Zifa WANG State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Chinese Academy of Environmental Planning Beijing 100041China University of Chinese Academy of Sciences Beijing 100049China institute of Urban meteorology China Meteorology AdministrationBeijing 100089China Unit 93.13.of PLA Beijing 100085China

Quantifying differences in secondary organic aerosols(SOAs)between the preindustrial period and the present day is crucial to assess climate forcing and environmental effects resulting from anthropogenic *** lack of vegetation information for the preindustrial period and the uncertainties in describing SOA formation are two leading factors preventing simulation of *** study calculated the online emissions of biogenic volatile organic compounds(VOCs)in the Aerosol and Atmospheric Chemistry Model of the institute of Atmospheric Physics(IAP-AACM)by coupling the Model of Emissions of Gases and Aerosols from Nature(MEGAN),where the input vegetation parameters were simulated by the IAP Dynamic Global Vegetation Model(IAP-DGVM).The volatility basis set(VBS)approach was adopted to simulate SOA formation from the nontraditional pathways,i.e.,the oxidation of intermediate VOCs and aging of primary organic *** biogenic SOAs(BSOAs)were dominant in SOAs globally in the preindustrial period,the contribution of nontraditional anthropogenic SOAs(ASOAs)to the total SOAs was up to 3..7%.In the present day,the contribution of ASOAs was 2.8 times larger than that in the preindustrial *** contribution of nontraditional sources of SOAs to SOA was as high as 53.1%.The influence of increased anthropogenic emissions in the present day on BSOA concentrations was greater than that of increased biogenic emission *** response of BSOA concentrations to anthropogenic emission changes in the present day was more sensitive than that in the preindustrial *** nontraditional sources and the atmospheric oxidation capability greatly affect the global SOA change.

关键词： IAP-AACM VBS MEGAN secondary organic aerosol anthropogenic and biogenic emissions

Reflection behavior of insensitive explosive detonation propagating around a cylinder

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Acta Mechanica Sinica 2024年第7期40卷 55-65页

作者： Zixuan Zhang Yuan Wang Xiaomian Hu Haitao Chen institute of applied Physics and Computational Mathematics Beijing 100094China Graduate School of China Academy of Engineering Physics Beijing 100088China

Insensitive explosive detonation has wide applications in compressing and driving inert materials,and thereby the interaction between detonation and inert materials has received more *** this paper,a two-dimensional numerical simulation based on the Euler multiphase flow framework is used to investigate the reflection behavior of the insensitive explosive detonation propagating around a *** results show that there is a critical incident angle,defined as transition angle for detonation propagating around the cylinder,below which the regular reflection(RR)on the cylinder surface is *** the incident angle is greater than the transition angle,RR changes to Mach *** transition angle is larger than that obtained by polar curve theory and the change of incident angle is used to interpret above *** addition,the influence of cylindrical radius and detonation reaction zone width on the reflection behavior is *** the cylindrical radius increases,the height of Mach stem increases while the transition angle decreases and gradually approaches the value in pole curve *** Neumann reflection is observed when the reaction zone width is relatively *** is because the energy release rate in the reaction zone is high for small reaction zone width,resulting in the formation of a series of compression waves near the cylindrical interface.

关键词： Insensitive explosive detonation Cylindrical inert material Reflection behavior

Flow instability of supercritical hydrocarbon fuel in a multi-channel cooling system

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Chinese Journal of Aeronautics 2024年第2期37卷 283-295页

作者： Yichao JIN Kun WU Xuejun FAN institute of applied Physics and Computational Mathematics Beijing 100094China institute of Mechanics Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Thermally-induced flow instabilities are a critical issue in multi-channel regenerative cooling *** particular,the interactions between Density-Wave Oscillations(DWO)and Flow Maldistribution(FMD)can result in complex and disastrous instability *** study investigates the instability behaviors of hydrocarbon fluid in a four-channel system with a constant heat flux ratio using both frequency-and time-domain *** the heat flux increases,the in-tube flow sequentially destabilizes in each channel and converges to new equilibrium states,leading to the emergence of FMD *** also causes the system eigenvalue to change repeatedly from negative to positive rather than increasing ***,the system eigenvalues are between those of the two most unstable channels,indicating that the stability behavior of the entire system is dictated by the most unstable *** FMD occurs,flow oscillations are activated in channels with weak stability,and the in-tube flow is observed to evolve into various flow patterns,including stable flow,self-sustained oscillation,oscillation divergence,quasiperiodic oscillation,and oscillation *** novel instability mode of oscillation excursion involves a spontaneous transition of operating *** oscillates from an equilibrium state and then stabilizes at a new operational state after oscillation-induced ***,the newfound stable state may also be only temporary,with the in-tube flow regressing to the initial state,resulting in quasi-periodic oscillation.

关键词： Cooling Supercritical fluids Hydrocarbons Flow instability Flow maldistribution Density-wave oscillations

Co-influence of the start of thermal growing season and precipitation on vegetation spring green-up on the Tibetan Plateau

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Advances in Climate Change Research 2024年第2期15卷 327-337页

作者： Chen-Peng WANG Meng-Tian HUANG Pan-Mao ZHAI State Key Laboratory of Severe Weather and institute of Global Change and Polar meteorology Chinese Academy of Meteorological SciencesBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China

The climate in the Tibetan Plateau(TP)has undergone significant change in recent decades,mainly in thermal and water conditions,which plays a crucial role in phenological changes in vegetation spring ***,how the start of the thermal growing season(SOS-T)and the start of the rainy season(SORS)as key climatic factors affect vegetation green-up remains *** that these factors characterize thermal and water conditions required for vegetation green-up,this study investigated changes in the SOS-T and SORS from 1961 to 2022,using observation-based datasets with long time *** found that the SOS-T and SORS have advanced across the TP in 1961-2022 and have shown a spatial pattern of advancement in the east and delay in the west in ***,the co-effect of temperature and precipitation change on the start of vegetation growing season(SOS-V)in 2000-2022 was *** across TP,the SOS-V had an early onset of 1.3.d per decade during 2000-2022,corresponding to advanced SOS-T and ***,the SOS-V generally occurred nearly at the same time as the SOS-T in the high-altitude meadow region.A substantial delay in the SOS-V relative to the SOS-T was observed in the desert,shrub,grassland and forest regions and generally kept pace with the ***,for 50%of the vegetated regions on the TP,inter-annual variation in the delay in the SOS-V relative to the SOS-T was dominated by precipitation change,which was profound in warm-climate *** study highlights the co-regulation of precipitation and temperature change in the SOS-V in different vegetation cover regions in the TP,offering a scientific foundation for comprehending the impact of climate change and prospects for vegetation phenology on the TP.

关键词： Tibetan Plateau Start of growing season Temperature Precipitation Climate change

Comparison of Adaptive Simulation Observation Experiments of the Heavy Rainfall in South China and Sichuan Basin

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Advances in Atmospheric Sciences 2024年第11期41卷 2173-2191页

作者： Linbin HE Weiyi PENG Yu ZHANG Shiguang MIAO Siqi CHEN Jiajing LI Duanzhou SHAO Xutao ZHANG College of Ocean and meteorology Guangdong Ocean UniversityZhanjiang 524088China Chinese Academy of meteorology Sciences Beijing 100081China institute of Urban meteorology China Meteorological AdministrationBeijing 100089China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Dalian Marine Center Ministry of Nature Resources of the People's Republic of ChinaDalian 116001China

This study examines the effectiveness of adaptive observation experiments using the ensemble transformation sensitivity(ETS) method to improve precipitation forecasts during heavy rainfall events in South China and the Sichuan Basin. High-resolution numerical models are employed to simulate adaptive observations. By identifying the sensitive areas of key weather system positions 42 hours before heavy rainfall events, the adaptive observations improve the prediction of jet streams, strong winds, and shear lines, which are essential for accurate heavy rainfall forecasting. This improvement is reflected in both the precipitation structure and location accuracy within the verification region. In South China, targeted observations enhance rainfall predictions by improving water vapor transport. In the Sichuan Basin, adaptive observations refine water vapor transport and adjust vortex dynamics. This research highlights the importance of accurately predicting shear lines and jet streams for forecasting heavy rainfall in these areas. Overall, this study found that adaptive observation enhances the precipitation forecast skills of the structure and location for heavy rainfall in South China and the Sichuan Basin, emphasizing their potential utility in operational numerical weather prediction.

关键词： adaptive observation ensemble transform sensitivity data assimilation rainfall

A novel triple periodic minimal surface-like plate lattice and its data-driven optimization method for superior mechanical properties

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applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 217-238页

作者： Yanda WANG Yanping LIAN Zhidong WANG Chunpeng WANG Daining FANG State Key Laboratory for Turbulence and Complex Systems&Center for applied Physics and Technology College of EngineeringPeking UniversityBeijing 100871China institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

Lattice structures can be designed to achieve unique mechanical properties and have attracted increasing attention for applications in high-end industrial equipment,along with the advances in additive manufacturing(AM)*** this work,a novel design of plate lattice structures described by a parametric model is proposed to enrich the design space of plate lattice structures with high connectivity suitable for AM *** parametric model takes the basic unit of the triple periodic minimal surface(TPMS)lattice as a skeleton and adopts a set of generation parameters to determine the plate lattice structure with different topologies,which takes the advantages of both plate lattices for superior specific mechanical properties and TPMS lattices for high connectivity,and therefore is referred to as a TPMS-like plate lattice(TLPL).Furthermore,a data-driven shape optimization method is proposed to optimize the TLPL structure for maximum mechanical properties with or without the isotropic *** this method,the genetic algorithm for the optimization is utilized for global search capability,and an artificial neural network(ANN)model for individual fitness estimation is integrated for high efficiency.A set of optimized TLPLs at different relative densities are experimentally validated by the selective laser melting(SLM)fabricated *** is confirmed that the optimized TLPLs could achieve elastic isotropy and have superior stiffness over other isotropic lattice structures.

关键词： lattice structure triple periodic minimal surface(TPMS) plate lattice structural optimization machine learning

Three-dimensional thermohaline structure estimation derived from HY-2 satellite data over the Maritime Silk Road and its applications

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Acta Oceanologica Sinica 2024年第5期43卷 41-53页

作者： Zhiqiang Chen Xidong Wang Xiangyu Wu Yuan Cao Zikang He Dakui Wang Jian Chen Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210024China Laboratory for Regional Oceanography and Numercial Modeling Qingdao Marine Science and Technology CenterQingdao 266061China National Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijing 100081China beijing institute of applied {3. Beijing 100029China

Estimated ocean subsurface fields derived from satellite observations provide potential data sources for operational marine environmental monitoring and prediction *** study employs a statistic regression reconstruction method,in combination with domestic autonomous sea surface height and sea surface temperature observations from the Haiyang-2(HY-2)satellite fusion data,to establish an operational quasi-realtime three-dimensional(3.)temperature and salinity products over the Maritime Silk *** products feature a daily temporal resolution and a spatial resolution of 0.25°×0.25°and exhibit stability and *** have demonstrated the accuracy of the reconstructed thermohaline fields in capturing the 3. thermohaline variations through comprehensive statistical evaluations,after comparing them against Argo observations and ocean analysis data from *** results illustrate that the reconstructed fields effectively represent seasonal variations in oceanic subsurface structures,along with structural changes resulting from mesoscale processes,and the upper ocean’s responses to tropical ***,the incorporation of HY-2 satellite observations notably enhances the accuracy of temperature and salinity reconstructions in the Northwest Pacific Ocean and marginally improves salinity reconstruction accuracy in the North Indian Ocean when compared to the World Ocean Atlas 2018 monthly climatology thermohaline *** a result,the reconstructed product holds promise for providing quasi-real-time 3. temperature and salinity field information to facilitate fast decisionmaking during emergencies,and also offers foundational thermohaline fields for operational ocean reanalysis and forecasting *** contributions enhance the safety and stability of ocean subsurface activities and navigation.

关键词： HY-2 satellite observations subsurface structures reconstruction Maritime Silk Road operational thermohaline product