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Information Geometric Structures for the Thermodynamic Manifold
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作者 张士诚 孙华飞 李春辉 《Journal of Beijing Institute of Technology》 EI CAS 2010年第4期491-494,共4页
In view of information geometry,the state space S of thermodynamic parameters is investigated.First a Riemannian metric for S is defined and then the α-geometric structures of S is given.Some of results obtained by o... In view of information geometry,the state space S of thermodynamic parameters is investigated.First a Riemannian metric for S is defined and then the α-geometric structures of S is given.Some of results obtained by other authors are extended. 展开更多
关键词 thermodynamic manifold information geometry geometric structure
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Fine Structure Constant Model Demonstrates the Electron Elementary Charge of Having an Intrinsic Manifold
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作者 Emmanouil Markoulakis Emmanuel Antonidakis 《Journal of Applied Mathematics and Physics》 2022年第10期2923-2939,共17页
Using our recently published electron’s charge electromagnetic flux manifold fiber model of the electron, described by analytical method and numerical simulations, we show how the fine structure constant is embedded ... Using our recently published electron’s charge electromagnetic flux manifold fiber model of the electron, described by analytical method and numerical simulations, we show how the fine structure constant is embedded as a geometrical proportionality constant in three dimensional space of its charge manifold and how this dictates the first QED term one-loop contribution of its anomalous magnetic moment making for the first time a connection of its intrinsic characteristics with physical geometrical dimensions and therefore demonstrating that the physical electron charge cannot be dimensionless. We show that the fine structure constant (FSC) α, and anomalous magnetic moment α<sub>μ</sub> of the electron is related to the sphericity of its charge distribution which is not perfectly spherical and thus has a shape, and therefore its self-confined charge possesses measurable physical dimensions. We also explain why these are not yet able to be measured by past and current experiments and how possible we could succeed. 展开更多
关键词 Electron Charge manifold Electron Fiber Model Compton Electron Fine structure Constant Anomalous Magnetic Moment Electron Dipole Moment Classical Electrodynamics Electron Geometry
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HAMILTONIAN STRUCTURE FOR RIGID BODY WITH FLEXIBLE ATTACHMENTS IN A CIRCULAR ORBIT 被引量:1
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作者 程耀 黄克累 陆启韶 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1993年第1期72-79,共8页
Hamiltonian structure of a rigid body in a circular orbit is established in this paper. With the reduction technique, the Hamiltonian structure of a rigid body in a circular orbit is derived from Lie-Poisson structure... Hamiltonian structure of a rigid body in a circular orbit is established in this paper. With the reduction technique, the Hamiltonian structure of a rigid body in a circular orbit is derived from Lie-Poisson structure of semidirect product, and Hamiltonian is derived from Jacobi's integral. The above method can be generalized to establish the Hamiltonian structure of a rigid body with a flexible attachment in a circular or- bit. At last, an example of stability analysis is given. 展开更多
关键词 Hamiltonian structure Poisson manifold rigid-elastic coupled system semidirect product circular orbit
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Recent developments in the structural design and optimization of ITER neutral beam manifold
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作者 曹诚志 潘宇东 +3 位作者 夏志伟 李波 江涛 李伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第2期180-185,共6页
This paper describes a new design of the neutral beam manifold based on a more optimized support system.A proposed alternative scheme has presented to replace the former complex manifold supports and internal pipe sup... This paper describes a new design of the neutral beam manifold based on a more optimized support system.A proposed alternative scheme has presented to replace the former complex manifold supports and internal pipe supports in the final design phase.Both the structural reliability and feasibility were confirmed with detailed analyses.Comparative analyses between two typical types of manifold support scheme were performed.All relevant results of mechanical analyses for typical operation scenarios and fault conditions are presented.Future optimization activities are described,which will give useful information for a refined setting of components in the next phase. 展开更多
关键词 ITER neutral beam manifold optimized design on supports structural seismic analysis
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Spontaneous Emergence of Physical Structures and Observable Formations: Fluctuations, Waves, Turbulent Pulsations and So on
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作者 L. I. Petrova 《Journal of Applied Mathematics and Physics》 2016年第5期863-870,共8页
As it is known, the closed inexact exterior form and associated closed dual form make up a differential-geometrical structure. Such a differential-geometrical structure describes a physical structure, namely, a pseudo... As it is known, the closed inexact exterior form and associated closed dual form make up a differential-geometrical structure. Such a differential-geometrical structure describes a physical structure, namely, a pseudostructure on which conservation laws are fulfilled (A closed dual form describes a pseudostructure. And a closed exterior form, as it is known, describes a conservative quantity, since the differential of closed form is equal to zero). It has been shown that closed inexact exterior forms, which describe physical structures, are obtained from the equations of mathematical physics. This process proceeds spontaneously under realization of any degrees of freedom of the material medium described. Such a process describes an emergence of physical structures and this is accompanied by an appearance of observed formations such as fluctuations, waves, turbulent pulsations and so on. 展开更多
关键词 Skew-Symmetric Form Nonidentical Relation Degenerate Transformation the Transition from the Nonintegrable manifolds to the Integrable structures
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Delineating homogeneous domains of fractured rocks using topological manifolds and deep learning
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作者 Yongqiang Liu Jianping Chen +3 位作者 Fujun Zhou Jiewei Zhan Wanglai Xu Jianhua Yan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2996-3013,共18页
Determining homogeneous domains statistically is helpful for engineering geological modeling and rock mass stability evaluation.In this text,a technique that can integrate lithology,geotechnical and structural informa... Determining homogeneous domains statistically is helpful for engineering geological modeling and rock mass stability evaluation.In this text,a technique that can integrate lithology,geotechnical and structural information is proposed to delineate homogeneous domains.This technique is then applied to a high and steep slope along a road.First,geological and geotechnical domains were described based on lithology,faults,and shear zones.Next,topological manifolds were used to eliminate the incompatibility between orientations and other parameters(i.e.trace length and roughness)so that the data concerning various properties of each discontinuity can be matched and characterized in the same Euclidean space.Thus,the influence of implicit combined effect in between parameter sequences on the homogeneous domains could be considered.Deep learning technique was employed to quantify abstract features of the characterization images of discontinuity properties,and to assess the similarity of rock mass structures.The results show that the technique can effectively distinguish structural variations and outperform conventional methods.It can handle multisource engineering geological information and multiple discontinuity parameters.This technique can also minimize the interference of human factors and delineate homogeneous domains based on orientations or multi-parameter with arbitrary distributions to satisfy different engineering requirements. 展开更多
关键词 Homogeneous domain Geological domain Geotechnical domain structural domain Topological manifold Deep learning
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Two theorems on cosymplectic hypersurfaces of six-dimensional Hermitian submanifolds of Cayley algebra 被引量:1
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作者 Mihail Banaru (Smolensk University of Humanities, Smolensk 214014, Russia) 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第1期38-40,共3页
Proves that cosymplectic hypersurfaces of six dimensional Hermitian submanifolds of the octave algebra are ruled manifolds and establishes a necessary and sufficient condition for a cosymplectic hypersurface of Hermit... Proves that cosymplectic hypersurfaces of six dimensional Hermitian submanifolds of the octave algebra are ruled manifolds and establishes a necessary and sufficient condition for a cosymplectic hypersurface of Hermitian M 6 O  to be a minimal submanifold of M 6. 展开更多
关键词 Hermitian manifold almost contact metric structure ruled manifold minimal submanifold cosymplectic structure
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Embeddings of Almost Hermitian Manifold in Almost Hyper Hermitian Manifold and Complex (Hypercomplex) Numbers in Riemannian Geometry 被引量:1
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作者 Alexander A Ermolitski 《Applied Mathematics》 2014年第16期2464-2475,共12页
Tubular neighborhoods play an important role in differential topology. We have applied these constructions to geometry of almost Hermitian manifolds. At first, we consider deformations of tensor structures on a normal... Tubular neighborhoods play an important role in differential topology. We have applied these constructions to geometry of almost Hermitian manifolds. At first, we consider deformations of tensor structures on a normal tubular neighborhood of a submanifold in a Riemannian manifold. Further, an almost hyper Hermitian structure has been constructed on the tangent bundle TM with help of the Riemannian connection of an almost Hermitian structure on a manifold M then, we consider an embedding of the almost Hermitian manifold M in the corresponding normal tubular neighborhood of the null section in the tangent bundle TM equipped with the deformed almost hyper Hermitian structure of the special form. As a result, we have obtained that any Riemannian manifold M of dimension n can be embedded as a totally geodesic submanifold in a Kaehlerian manifold of dimension 2n (Theorem 6) and in a hyper Kaehlerian manifold of dimension 4n (Theorem 7). Such embeddings are “good” from the point of view of Riemannian geometry. They allow solving problems of Riemannian geometry by methods of Kaehlerian geometry (see Section 5 as an example). We can find similar situation in mathematical analysis (real and complex). 展开更多
关键词 RIEMANNIAN manifolds ALMOST HERMITIAN and ALMOST HYPER HERMITIAN structures TANGENT Bundle
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On Some Recent Progress in Complex Geometry-the Area Related to Homogeneous Manifolds 被引量:1
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作者 GUAN Daniel 《Chinese Quarterly Journal of Mathematics》 2020年第2期111-144,共34页
In this article,we give a survey of some progress of the complex geometry,mostly related to the Lie group actions on compact complex manifolds and complex homogeneous spaces in the last thirty years.In particular,we e... In this article,we give a survey of some progress of the complex geometry,mostly related to the Lie group actions on compact complex manifolds and complex homogeneous spaces in the last thirty years.In particular,we explore some works in the special area in Di erential Geometry,Lie Group and Complex Homogeneous Space.Together with the special area in nonlinear analysis on complex manifolds,they are the two major aspects of my research interests. 展开更多
关键词 Invariant structure Homogeneous space Complex torus bundles Hermitian manifolds Reductive Lie group Compact manifolds Ricci form Locally conformal Kahler manifolds
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ON THE INVARIANT SUBMANIFOLDS OF RIEMANNIAN PRODUCT MANIFOLD
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作者 M.Atceken S.Keles 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期549-558,共10页
In this paper, the vertical and horizontal distributions of an invariant sub-manifold of a Riemannian product manifold are discussed. An invariant real space form in a Riemannian product manifold is researched. Finall... In this paper, the vertical and horizontal distributions of an invariant sub-manifold of a Riemannian product manifold are discussed. An invariant real space form in a Riemannian product manifold is researched. Finally, necessary and sufficient conditions are given on an invariant submanifold of a Riemannian product manifold to be a locally symmetric and real space form. 展开更多
关键词 Riemannian product manifold mixed geodesic submanifold real space form and almost Riemannian product structure
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The U-Kenmotsu Hypersurfaces Axiom and Six-Dimensional Hermitian Submanifolds of Cayley Algebra
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作者 Mihail BANARU 《四川理工学院学报(自然科学版)》 CAS 2013年第3期1-5,共5页
Six-dimensional Hermitian submanifolds of Cayley algebra are considered.It is proved that if such a submanifold of the octave algebta complies with the U-Kenmotsu hypersurfaces axiom,then it is Khlerian.
关键词 almost contact metric structure Kenmotsu structure Khlerian manifold almost Hermitian manifold
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Semi-Supervised Dimensionality Reduction of Hyperspectral Image Based on Sparse Multi-Manifold Learning
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作者 Hong Huang Fulin Luo +1 位作者 Zezhong Ma Hailiang Feng 《Journal of Computer and Communications》 2015年第11期33-39,共7页
In this paper, we proposed a new semi-supervised multi-manifold learning method, called semi- supervised sparse multi-manifold embedding (S3MME), for dimensionality reduction of hyperspectral image data. S3MME exploit... In this paper, we proposed a new semi-supervised multi-manifold learning method, called semi- supervised sparse multi-manifold embedding (S3MME), for dimensionality reduction of hyperspectral image data. S3MME exploits both the labeled and unlabeled data to adaptively find neighbors of each sample from the same manifold by using an optimization program based on sparse representation, and naturally gives relative importance to the labeled ones through a graph-based methodology. Then it tries to extract discriminative features on each manifold such that the data points in the same manifold become closer. The effectiveness of the proposed multi-manifold learning algorithm is demonstrated and compared through experiments on a real hyperspectral images. 展开更多
关键词 HYPERSPECTRAL IMAGE Classification Dimensionality Reduction Multiple manifoldS structure SPARSE REPRESENTATION SEMI-SUPERVISED Learning
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Smoother manifold for graph meta-learning
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作者 ZHAO Wencang WANG Chunxin XU Changkai 《High Technology Letters》 EI CAS 2022年第1期48-55,共8页
Meta-learning provides a framework for the possibility of mimicking artificial intelligence.How-ever,data distribution of the training set fails to be consistent with the one of the testing set as the limited domain d... Meta-learning provides a framework for the possibility of mimicking artificial intelligence.How-ever,data distribution of the training set fails to be consistent with the one of the testing set as the limited domain differences among them.These factors often result in poor generalization in existing meta-learning models.In this work,a novel smoother manifold for graph meta-learning(SGML)is proposed,which derives the similarity parameters of node features from the relationship between nodes and edges in the graph structure,and then utilizes the similarity parameters to yield smoother manifold through embedded propagation module.Smoother manifold can naturally filter out noise from the most important components when generalizing the local mapping relationship to the global.Besides suiting for generalizing on unseen low data issues,the framework is capable to easily perform transductive inference.Experimental results on MiniImageNet and TieredImageNet consistently show that applying SGML to supervised and semi-supervised classification can improve the performance in reducing the noise of domain shift representation. 展开更多
关键词 META-LEARNING smoother manifold similarity parameter graph structure
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基于包络学习和分级结构一致性机制的不平衡集成算法 被引量:1
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作者 李帆 张小恒 +1 位作者 李勇明 王品 《电子学报》 EI CAS CSCD 北大核心 2024年第3期751-761,共11页
集成方法是不平衡学习方法的重要分支,然而,现有不平衡集成方法均作用于原样本而没考虑样本的结构信息,因此其效能仍然有限.样本的结构信息包括局部和全局结构信息.为了解决上述问题,本文提出了一种基于深度样本包络网络(Deep Instance ... 集成方法是不平衡学习方法的重要分支,然而,现有不平衡集成方法均作用于原样本而没考虑样本的结构信息,因此其效能仍然有限.样本的结构信息包括局部和全局结构信息.为了解决上述问题,本文提出了一种基于深度样本包络网络(Deep Instance Envelope Network,DIEN)和分级结构一致性机制(Hierarchical Structure Consistency Mechanism,HSCM)的不平衡集成学习算法.该算法在考虑局部流形和全局结构信息的情况下,通过多层样本聚类,生成高质量的多层包络样本,从而实现类平衡化.首先,算法基于样本近邻拼接和模糊C均值聚类算法,设计DIEN来挖掘样本的结构信息,得到深度包络样本.然后,设计局部流形结构度量和全局结构分布度量来构建HSCM用于增强层间样本的分布一致性.接着,将DIEN和HSCM结合起来,构建出优化后的深度样本包络网络——DH(DIEN with HSCM).之后,将基分类器应用于包络样本.最后,设计bagging集成学习机制来融合基分类器的预测结果.文末组织了多组实验,采用了十多个公共数据集和有代表性的相关算法进行验证比较.实验结果表明,本文算法在AUC(Area Under Curve),F-measure等四个性能指标上显著最优. 展开更多
关键词 不平衡学习 包络学习 分级结构一致性机制 局部流形结构度量 全局结构分布度量
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浅水受限区水下油气田开发方案 被引量:1
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作者 孟凡然 张重德 +3 位作者 曹永 张文龙 王刚 贾鹏 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第4期779-785,共7页
针对国内浅水油气资源开发环境影响及空间受限等问题,本文提出了国产浅水水下生产系统的总体设计方案。通过对浅水水下生产系统关键设备结构进行分析,提出了一种满足受限区海域开发要求的环境友好型设计思路。结果表明:通过系统和总体... 针对国内浅水油气资源开发环境影响及空间受限等问题,本文提出了国产浅水水下生产系统的总体设计方案。通过对浅水水下生产系统关键设备结构进行分析,提出了一种满足受限区海域开发要求的环境友好型设计思路。结果表明:通过系统和总体布置的设计,国产浅水水下生产系统与深水相比在单体重量、作业方式、维护检修方面更加经济。 展开更多
关键词 浅水采油树 浅水水下控制模块 水下防护结构 浅水水下生产系统 水下管汇 湿插拔水下电连接器 水下湿插拔液压连接器 节流阀
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局部结构自适应的线性投影方法研究
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作者 杨兴 王士同 胡文军 《计算机科学》 CSCD 北大核心 2024年第S02期627-633,共7页
流形学习的核心是通过保持局部结构来捕捉数据中隐藏的几何信息,而局部结构通常利用冗余或干扰的原始数据进行评价,这意味着局部结构是不可靠的,存在局部结构置信度不足的问题。为此,针对性地提出一种局部结构自适应的线性投影方法。该... 流形学习的核心是通过保持局部结构来捕捉数据中隐藏的几何信息,而局部结构通常利用冗余或干扰的原始数据进行评价,这意味着局部结构是不可靠的,存在局部结构置信度不足的问题。为此,针对性地提出一种局部结构自适应的线性投影方法。该方法的核心在于:一方面,它强制线性投影后的低维表示保持高维空间中的局部结构;另一方面,通过低维空间表示更新高维空间中的局部结构,并通过循环迭代方式实现局部结构的自适应。真实数据集上的实验结果表明,所提方法在各项性能指标上均优于其他对比方法。 展开更多
关键词 流形学习 局部结构 置信度 自适应 线性投影
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基于内嵌式微通道芯片散热结构设计研究综述
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作者 熊园园 刘沛 +2 位作者 付予 焦斌斌 芮二明 《集成电路与嵌入式系统》 2024年第7期12-18,共7页
电子芯片/系统的尺寸微型化、功能复合化导致了其功率密度的增大,伴随着发热也越来越严重,如何应对电子芯片/系统逐渐增加的热流密度,成为散热设计中面临的巨大挑战,也是当前研究的热点。本文详细论述了传统散热技术的优缺点,对国内外... 电子芯片/系统的尺寸微型化、功能复合化导致了其功率密度的增大,伴随着发热也越来越严重,如何应对电子芯片/系统逐渐增加的热流密度,成为散热设计中面临的巨大挑战,也是当前研究的热点。本文详细论述了传统散热技术的优缺点,对国内外正在开展的内嵌式微通道散热结构进行了系统分析,并着重对基于内嵌式微通道芯片散热技术原理、散热性能和创新性解决方案进行了归纳总结。在分析当前国内外解决方案的基础上,总结了基于内嵌式微通道的芯片散热设计经验和结论,以及面临的挑战,基于此给出了芯片散热设计研究现状和发展方向。 展开更多
关键词 芯片散热 内嵌式微通道 热流密度 散热结构 分层复杂歧管
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基于拓扑结构的液压阀体轻量化设计
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作者 杨思远 戴宁 +1 位作者 程筱胜 柏久阳 《机械设计与制造工程》 2024年第11期1-6,共6页
针对传统加工方法进行液压阀体轻量化设计过程复杂、轻量化效果较差等问题,提出一种参数化液压阀体轻量化设计方法。分析液压阀体各个接口功能与流道拓扑关系,提取流道的拓扑结构;根据流道拓扑关系,考虑流道性能约束与体积约束,重新设... 针对传统加工方法进行液压阀体轻量化设计过程复杂、轻量化效果较差等问题,提出一种参数化液压阀体轻量化设计方法。分析液压阀体各个接口功能与流道拓扑关系,提取流道的拓扑结构;根据流道拓扑关系,考虑流道性能约束与体积约束,重新设计流道的布局与结构;使用自支撑截面流道代替传统的圆形截面流道以避免流道内部生成支撑结构;提出变截面流道建模与流道路径优化算法,实现流道自动化设计。对某液压阀体进行轻量化设计实验并进行流体仿真测试,结果表明,轻量化设计方案下的阀体与原阀体相比质量平均减少93.5%,体积平均减少70.8%,压力损失平均减少66.2%。 展开更多
关键词 液压阀体 轻量化结构 增材制造 拓扑结构 参数化设计
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复合纳米流体在歧管微通道内的流动传热数值模拟
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作者 董辉 于珂凡 +1 位作者 赵亮 王进 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第7期960-966,共7页
对歧管微通道散热器中复合纳米流体的流动与传热特性进行数值模拟.以水基Al_(2)O_(3)-CuO复合纳米流体为工质,探讨纳米颗粒混合比例、体积分数(φ)、雷诺数(Re)以及引入凹槽对散热器流动换热的影响.结果表明,复合纳米流体在较高的体积... 对歧管微通道散热器中复合纳米流体的流动与传热特性进行数值模拟.以水基Al_(2)O_(3)-CuO复合纳米流体为工质,探讨纳米颗粒混合比例、体积分数(φ)、雷诺数(Re)以及引入凹槽对散热器流动换热的影响.结果表明,复合纳米流体在较高的体积分数和雷诺数下具有较好的热力学性能,但相应的压降也会增大.混合比例1∶4的复合纳米流体整体性能最优,在Re=100,φ=6%时,泵功消耗比单一的水基Al_(2)O_(3)纳米流体降低18.9%,综合性能指标提高21.7%.在歧管微通道的侧壁上添加不同形状的凹槽与光滑歧管微通道的换热效果基本相当. 展开更多
关键词 歧管微通道散热器 复合纳米流体 凹槽结构 流动与传热
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基于流固耦合的水下发球管汇力学及振动特性分析 被引量:1
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作者 鞠朋朋 柳英明 +1 位作者 张欢 李林 《科学技术与工程》 北大核心 2024年第4期1471-1479,共9页
水下发球系统具有可利用生产流体发球、不停井发球的优势,在现阶段与未来海洋油气开发具有广阔的应用前景。水下发球管汇结构复杂,存在多处弯管、变径三通,生产流体压力高,而发球工艺操作引起的管汇结构变形与振动情况尚不清晰。采用数... 水下发球系统具有可利用生产流体发球、不停井发球的优势,在现阶段与未来海洋油气开发具有广阔的应用前景。水下发球管汇结构复杂,存在多处弯管、变径三通,生产流体压力高,而发球工艺操作引起的管汇结构变形与振动情况尚不清晰。采用数值模拟的方法,计算了某水下发球管汇在发球工况中,流固耦合条件下管汇结构的位移、应力分布及振动情况。发现阀门的开关瞬间是压力变化幅度最大的特征时刻,也是引起管道位移、振动情况最严重的特征时刻;明确了管道结构风险位点为管汇结构末端,最大位移约为5.69 mm,主要由X方向贡献,最大等效应力为233.13 MPa,主要集中分布在T型管、弯管内侧处;提出了针对性的优化支撑方案,管汇结构最大位移降低至3.53 mm,低阶模态频率增幅约为1.74%~20.54%,说明管汇结构的安全性得到了提高。研究成果可为水下发球管汇的设计、运行提供理论依据。 展开更多
关键词 数值模拟 流固耦合 水下发球管汇 力学特性 振动特性
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