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A sharp-interface immersed smoothed point interpolation method with improved mass conservation for fluid-structure interaction problems

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Journal of Hydrodynamics 2020年第2期32卷 267-285页

作者： Bo-qian Yan shuangqiang wang Gui-yong Zhang Chen Jiang Qi-hang Xiao Zhe Sun State Key Laboratory of Structural Analysis for Industrial Equipment School of Naval ArchitectureDalian University of TechnologyDalian116023China Department of Fisheries and Oceans Bedford Institute of OceanographyDartmouthCanada Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai200240China Key Laboratory of Traffic Safety on Track of Ministry of Education School of Traffic and Transportation EngineeringCentral South UniversityChangsha410076China Joint International Research Laboratory of Key Technology for Rail Traffic Safety Central South UniversityChangsha410076China National and Local Joint Engineering Research Center of Safety Technology for Rail Vehicle Central South UniversityChangsha410076China

To solve the problem of inaccurate boundary identification and to eliminate the spurious pressure oscillation in the previously developed immersed smoothed point interpolation method(IS-PIM),a new sharp-interface IS-PIM combining mass conservation algorithm,called Sharp-ISPIM-Mass,is proposed in this *** on the so called sharp-interface method,the technique of quadratic local velocity reconstruction has been developed by combining with the mass conservation algorithm,which enables the present method improve the accuracy of the velocity field and satisfy the mass conservation condition near the boundary *** the proposed method would not encounter the problem of spurious mass *** addition,a new form of FSI force evaluation considering pressure and viscous force to perform a whole function from the fluid domain to fictitious fluid domain is introduced,which makes the present method obtain more accurate results of FSI force than the original *** the numerical studies of a number of benchmark examples,the performance of the Sharp-ISPIM-Mass has been examined and illustrated.

关键词： Sharp-interface technique immersed type method mass conservation algorithm fluid-structure interaction(FSI)

Single-pulse Emissions of PSRs J1611-0114 and J1617+1123

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Research in Astronomy and Astrophysics 2024年第11期24卷 1-10页

作者： Shifang Liu Zhigang Wen shuangqiang wang Feifei Kou Wenming Yan Jianping Yuan Qingdong Wu De Zhao Chenchen Miao Na wang Menyao Xue Di Li Pei wang Shengnan Sun Weiwei Zhu Juntao Bai School of Physics and Technology Xinjiang UniversityUrumqi 830046China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830046China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830046China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Department of Astronomy Tsinghua UniversityBeijing 100084China

In this paper,the emissions from two pulsars,PSRs J1611-0114 and J1617+1123,were investigated using th Five-hundred-meter Aperture Spherical radio Telescope operating at a central frequency of 1250 *** average pulse profile of PSR J1611-0114 shows two components,the first of which is relatively weak in intensity The two-dimensional pulse stack exhibits an obvious nulling phenomenon,with an estimated nulling fraction o40.1%±5.4%.The durations of the nulls and bursts are consistent with power-law distributions,and no periodi nulling phenomenon is *** results from PSR J1617+1123 demonstrate that the average pulse profile i composed of four *** peak intensity of the fourth component varies significantly,causing an unstabl integrated *** addition,the modulation characteristics of J1611-0114 and J1617+1123 were studied by analyzing the modulation index,longitude resolved fluctuation spectrum and two-dimensional fluctuation spectrum using the software *** was found that the two pulsars exhibit intensity *** particular,J1611-0114 displays even-odd modulation,with the modulation period of approximately two *** modulation period of J1617+1123 is relatively *** is an obvious subpulse drift phenomenon,and the value of P_(2)i~0.125c/P_(0),corresponding to 12 pulse longitude bins,and the drift rate(P_(2)/P_(3))is about 0.29.

关键词： stars neutron-(stars:)pulsars general-(stars:)pulsars individual(PSRs J1611-0114 and J1617+1123)

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基于光滑点插值方法的三维流固耦合问题研究

中国造船 2020年第S02期61卷 199-206页

作者：黄硕张桂勇王双强王鹏大连理工大学工业装备结构分析国家重点实验室船舶工程学院大连116024 上海交通大学高新船舶与深海开发装备协同创新中心上海200240 贝德福德海洋研究所渔业与海洋部加拿大达特茅斯B2Y4A2

基于浸没式光滑点插值方法(IS-PIM)解决置于不可压缩粘性流体域内大变形非线性固体的三维流固耦合问题.流体域控制方程(N-S方程)采用半隐式特征分离法(CBS)进行求解;基于显示时间积分,采用光滑点插值方法(S-PIM)求解非线性固体的瞬态动... 详细信息

基于浸没式光滑点插值方法(IS-PIM)解决置于不可压缩粘性流体域内大变形非线性固体的三维流固耦合问题.流体域控制方程(N-S方程)采用半隐式特征分离法(CBS)进行求解;基于显示时间积分,采用光滑点插值方法(S-PIM)求解非线性固体的瞬态动力学响应.针对虚拟流体,采用虚拟流体具有真实流体的物理属性和固体的运动属性两项假设实现流固耦合条件的连续.相关数值研究表明,浸没光滑点插值方法具有在三维流固耦合问题中准确模拟固体运动或变形和流动的能力.

关键词：光滑点插值方法流固耦合虚拟流体非线性固体

基于WCSPH-SPIM流固耦合模型的弹性体入水模拟

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振动与冲击 2020年第18期39卷 103-108页

作者：施书文张桂勇王双强胡泰安大连理工大学船舶工程学院辽宁省深海浮动结构工程实验室辽宁大连116024 大连理工大学工业装备与结构分析国家重点实验室辽宁大连116024 高新船舶与深海开发装备协同创新中心上海200240

对于入水砰击这类强非线性问题,运用网格方法不可避免会发生网格畸变、自由液面捕捉不准确等问题,而拉格朗日型无网格方法在处理该类问题时展现出很强的优越性。针对这一特点,采用两种无网格方法分别作为流体与固体求解器、建立流固耦... 详细信息

对于入水砰击这类强非线性问题,运用网格方法不可避免会发生网格畸变、自由液面捕捉不准确等问题,而拉格朗日型无网格方法在处理该类问题时展现出很强的优越性。针对这一特点,采用两种无网格方法分别作为流体与固体求解器、建立流固耦合模型模拟入水问题;在通过刚性体入水问题对弱可压光滑粒子水动力法(WCSPH)进行验证之后,采用新提出的弱可压光滑粒子水动力与光滑点插值(SPIM)流固耦合方法(WCSPH-SPIM)分别对弹性体低速和高速入水问题进行了计算。结果显示关键点处变形与压力随时间的变化情况都与试验值或半解析解吻合良好,证明了该方法对模拟弹性体入水问题的有效性。

关键词：弱可压光滑粒子水动力法(WCSPH) 光滑点插值方法(SPIM) 流固耦合(FSI) 入水

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轻质高强层状复合材料研究现状

轻金属 2017年第4期 50-54页

作者：王栓强王快社张金龙西安航空学院陕西西安710077 西安建筑科技大学陕西西安710055

综述了层状复合板材的研究现状。从制备技术、复合机理、界面形态等方面叙述了轻质、高强层状复合板材的研究现状和发展趋势,指出采用合适的工艺制备铝、镁、钛三种金属结构材料的层状板材,是获得轻质高强的结构材料的有效途径之一。

关键词：轻质金属层状复合材料稍备复合机理界面形态

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船舶与海洋工程流固耦合数值方法研究进展

中国舰船研究 2022年第5期17卷 52-73页

作者：张桂勇王双强孙哲肖启航大连理工大学船舶工程学院辽宁大连116024 大连理工大学工业装备与结构分析国家重点实验室辽宁大连116024 高新船舶与深海开发装备协同创新中心上海200240 贝德福德海洋研究所渔业与海洋部加拿大达特茅斯B2Y 4A2

流固耦合问题较为复杂,通常难以通过理论推导求得,而数值模拟则能提供一种有效的解决方案,并被广泛用于船舶与海洋工程领域。流固耦合数值方法根据其网格离散方式,可以分为贴体网格方法、非贴体网格方法、重叠网格方法和粒子类方法 4类... 详细信息

流固耦合问题较为复杂,通常难以通过理论推导求得,而数值模拟则能提供一种有效的解决方案,并被广泛用于船舶与海洋工程领域。流固耦合数值方法根据其网格离散方式,可以分为贴体网格方法、非贴体网格方法、重叠网格方法和粒子类方法 4类,对这4类方法的特点及研究进展进行概述并总结得出:贴体网格方法和重叠网格方法均能精确捕捉界面的变形和演化,适合高雷诺数流动问题,在考虑结构变形时一般采用贴体网格方法,而考虑复杂几何形状的刚体运动时则常采用重叠网格方法;非贴体网格方法能够避免网格的更新操作,使计算较为简单,目前多用于模拟流动控制、水下柔性仿生航行器的研发以及多体运动干扰等问题;粒子类方法因其固有的拉格朗日属性,在模拟涉及自由液面剧烈变形、砰击、爆炸等强非线性流固耦合问题中发挥着重要作用。不同的流固耦合问题属性决定了不同方法的适用性,如何选取适合的数值方法,同时结合各类方法的优势开发新的计算方法以应对更为复杂的问题,是流固耦合算法开发的重要发展方向。

关键词：流固耦合贴体网格方法非贴体网格方法重叠网格方法粒子类方法

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脉冲星发现50年

科技导报 2017年第18期35卷 52-57页

作者：张承民王双强尚伦华杨佚沿中国科学院国家天文台北京100020 中国科学院大学北京101400 中国科学院新疆天文台乌鲁木齐830001 北京师范大学天文系北京100089

脉冲星自1967年发现以来,50年的观测和理论研究取得巨大进展,期间曾2次获颁诺贝尔物理学奖。脉冲星以其高度致密和强引力场堪称宇宙天然实验室,可用来验证爱因斯坦广义相对论及进行引力波探测,推动了天文学与物理学研究的发展。本文简... 详细信息

脉冲星自1967年发现以来,50年的观测和理论研究取得巨大进展,期间曾2次获颁诺贝尔物理学奖。脉冲星以其高度致密和强引力场堪称宇宙天然实验室,可用来验证爱因斯坦广义相对论及进行引力波探测,推动了天文学与物理学研究的发展。本文简介了脉冲星的发现及其性质,并综述了脉冲星导航以及最近建成的500 m口径球面射电望远镜(FAST)的脉冲星探测研究进展。

关键词：脉冲星中子星引力波

An Iterated Greedy Algorithm with Memory and Learning Mechanisms for the Distributed Permutation Flow Shop Scheduling Problem

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Computers, Materials & Continua 2025年第1期82卷 371-388页

作者： Binhui wang Hongfeng wang College of Information Science and Engineering Northeastern UniversityShenyang110819China

The distributed permutation flow shop scheduling problem(DPFSP)has received increasing attention in recent *** iterated greedy algorithm(IGA)serves as a powerful optimizer for addressing such a problem because of its straightforward,single-solution evolution ***,a potential draw-back of IGA is the lack of utilization of historical information,which could lead to an imbalance between exploration and exploitation,especially in large-scale *** a consequence,this paper develops an IGA with memory and learning mechanisms(MLIGA)to efficiently solve the DPFSP targeted at the ***,we incorporate a memory mechanism to make a more informed selection of the initial solution at each stage of the search,by extending,reconstructing,and reinforcing the information from previous *** addition,we design a twolayer cooperative reinforcement learning approach to intelligently determine the key parameters of IGA and the operations of the memory ***,to ensure that the experience generated by each perturbation operator is fully learned and to reduce the prior parameters of MLIGA,a probability curve-based acceptance criterion is proposed by combining a cube root function with custom *** last,a discrete adaptive learning rate is employed to enhance the stability of the memory and *** ablation experiments are utilized to verify the effectiveness of the memory mechanism,and the results show that this mechanism is capable of improving the performance of IGA to a large ***,through comparative experiments involving MLIGA and five state-of-the-art algorithms on 720 benchmarks,we have discovered that MLI-GA demonstrates significant potential for solving large-scale *** indicates that MLIGA is well-suited for real-world distributed flow shop scheduling.

关键词： Distributed permutation flow shop scheduling makespan iterated greedy algorithm memory mechanism cooperative reinforcement learning

Quickly obtaining densely dispersed coherent particles in steel matrix and its related mechanical property

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 111-118页

作者： Xiaoxiao wang Qingsong Huang School of Chemical Engineering Sichuan UniversityChengdu 610065China

Densely distributed coherent nanoparticles(DCN)in steel matrix can enhance the work-hardening ability and ductility of steel *** the routes to this end can be generally classified into the liquid-solid route and the solid-solid ***,the formation of DCN structures in steel requires long processes and complex *** far,obtaining steel with coherent particle enhancement in a short time remains a bottleneck,and some necessary steps remain ***,we show a high-efficiency liquid-phase refining process reinforced by a dynamic magnetic ***-Y-Mn-O particles had an average size of around(3.53±1.21)nm and can be obtained in just around 180 *** small nanoparticles were coherent with the matrix,implying no accumulated dislocations between the particles and the steel *** findings have a potential application for improving material machining capacity,creep resistance,and radiation resistance.

关键词： ferritic steels coherent particles microstructure compression test work hardening