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Cu:KNSBN晶体稳态耦合增益系数角度选择性研究 被引量:1
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作者 马宝红 张战杰 石顺祥 《洛阳师范学院学报》 2010年第5期32-34,共3页
耦合波理论是分析光折变晶体的基本方法,针对Cu:KNSBN晶体中双光束耦合稳态耦合增益系数的角度选择性,利用耦合波理论做了分析,结果表明对于一定厚度的Cu:KNSBN晶体,双光束耦合的稳态耦合增益系数具有角度选择性.同时,对于这个结论进行... 耦合波理论是分析光折变晶体的基本方法,针对Cu:KNSBN晶体中双光束耦合稳态耦合增益系数的角度选择性,利用耦合波理论做了分析,结果表明对于一定厚度的Cu:KNSBN晶体,双光束耦合的稳态耦合增益系数具有角度选择性.同时,对于这个结论进行了相应的实验研究,实验结果和理论分析基本吻合. 展开更多
关键词 双光束耦合 稳态耦合增益系数 写入角
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SCWR堆芯稳态物理-热工水力耦合计算程序系统CASIR的开发 被引量:4
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作者 马永强 柴晓明 +2 位作者 王育威 潘俊杰 安萍 《核动力工程》 EI CAS CSCD 北大核心 2013年第1期87-91,共5页
针对超临界水冷反应堆(SCWR)堆芯冷却剂密度沿轴向变化剧烈的特点,开发用于SCWR堆芯稳态物理-热工水力耦合计算的程序系统CASIR。CASIR由改进的压水堆堆芯中子学计算程序和适用于SCWR燃料组件计算的子通道热工-水力程序组成,具备调整堆... 针对超临界水冷反应堆(SCWR)堆芯冷却剂密度沿轴向变化剧烈的特点,开发用于SCWR堆芯稳态物理-热工水力耦合计算的程序系统CASIR。CASIR由改进的压水堆堆芯中子学计算程序和适用于SCWR燃料组件计算的子通道热工-水力程序组成,具备调整堆芯下腔室入口流量分配的功能。针对CSR1000双流程的SCWR首循环堆芯,通过与蒙特卡罗程序对比寿期初时刻计算结果的方式,初步验证CASIR计算SCWR堆芯中子学问题的准确性;通过SCWR堆芯燃耗模拟,以及调整堆芯流量分布使得最大包壳表面温度(MCST)满足设计限值的测试,表明CASIR满足SCWR堆芯设计的要求,可应用于方形燃料组件的SCWR堆芯概念设计。 展开更多
关键词 超临界水冷反应堆 物理-热工水力耦合 概念设计 CASIR
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低速重载风电齿轮箱径向滑动轴承多运行状态润滑性能分析 被引量:1
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作者 赵帅可 苏华 《西北工业大学学报》 EI CAS CSCD 北大核心 2023年第5期978-986,共9页
针对风电齿轮箱中径向滑动轴承频繁启动、低速重载、偏航倾斜等工况,基于平均Reynolds方程建立径向滑动轴承瞬时启动与运行工况耦合的润滑性能数值分析模型,分析了启动阶段轴径轴心运动轨迹,获得启动至稳定阶段轴承膜厚变化状态;分别研... 针对风电齿轮箱中径向滑动轴承频繁启动、低速重载、偏航倾斜等工况,基于平均Reynolds方程建立径向滑动轴承瞬时启动与运行工况耦合的润滑性能数值分析模型,分析了启动阶段轴径轴心运动轨迹,获得启动至稳定阶段轴承膜厚变化状态;分别研究了表面综合粗糙度、轴颈倾斜角度、轴颈转速对轴承启动和稳定运行整个阶段润滑性能的影响规律。结果表明:启动阶段偏心率出现最大值,粗糙接触引起破膜风险最大;随着表面综合粗糙度由0.6增大至1.2μm,轴承承载力和摩擦因数均增加,启动阶段的最大承载力和摩擦因数比稳定阶段增加约13.62%和131.58%;随着轴径倾斜角度由0.0001°增大至0.0004°,轴承承载力和摩擦因数均增大,且启动阶段的最大承载力和摩擦因数比稳定阶段平均约高出30%和116%;随着转速的增加,轴承的承载力增大,摩擦因数减小,有利于提高轴承性能。计算结果为评价滑动轴承频繁启动工况下的磨损风险提供了重要依据,为滑动轴承的运行温度、油膜压力等轴承结构设计和选型提供参考。 展开更多
关键词 风电齿轮箱 轴心轨迹 /稳态耦合计算 微凸体承载比 轴颈倾斜 启停
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电-热多物理场耦合的对偶有限元分析 被引量:2
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作者 殷英 徐小宇 +1 位作者 闫帅 任卓翔 《电子设计工程》 2018年第21期11-15,共5页
随着集成电路、微机电系统的快速发展,各种物理场的交互作用成为影响电路可靠性或者增加设计难度的重要问题。其中,大量工程应用中都会发生稳恒电流场和热场的相互作用。电流场产生的焦耳热与电阻率的温变特性是这两个物理场之间双向相... 随着集成电路、微机电系统的快速发展,各种物理场的交互作用成为影响电路可靠性或者增加设计难度的重要问题。其中,大量工程应用中都会发生稳恒电流场和热场的相互作用。电流场产生的焦耳热与电阻率的温变特性是这两个物理场之间双向相互耦合的联系因素。当几何结构复杂时,分析该多物理场问题会有计算方面的挑战。通常利用有限元法来求解多物理问题,其中采取节点单元法来处理电流场。本论文首先在多物理耦合分析中实现了棱边单元法来分析电流场,并通过一个典型的微阻梁算例问题,与常规方法进行充分对比,考察了随着网格加密、与热场耦合迭代深度的对偶特点及收敛特性。 展开更多
关键词 对偶方程方法 有限元法 多物理场 电热耦合
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断块油田断层附近水平井产能 被引量:4
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作者 马帅 王雯娟 +3 位作者 张风波 黄静 李凤颖 张芨强 《大庆石油地质与开发》 CAS CSCD 北大核心 2016年第6期68-72,共5页
针对断块油田断层附近水平井产能预测难度较大的问题,采用离散化处理方法建立了断层附近油藏渗流和水平井井筒管流耦合模型,通过实例计算证明了模型的准确性。改变断层与井筒相对位置发现,井筒与断层平行时径向入流剖面呈"U"... 针对断块油田断层附近水平井产能预测难度较大的问题,采用离散化处理方法建立了断层附近油藏渗流和水平井井筒管流耦合模型,通过实例计算证明了模型的准确性。改变断层与井筒相对位置发现,井筒与断层平行时径向入流剖面呈"U"型分布;井筒距离断层越近产能越低,且产能降低幅度逐渐增大,当井筒紧贴断层时,产能降低为无断层时的一半。井筒与断层垂直时,远离断层端径向流量高于靠近断层端,且距离断层越近,跟趾端差异越明显、产能越低、产能降低幅度越大。断层附近水平井跟端靶点固定时,建议井眼轨迹垂直且远离断层,该情况下单井产能最高。整体上,井筒到断层距离对产能影响较大,井筒与断层夹角对径向入流剖面影响较大,这对断层附近水平井井眼轨迹设计具有一定指导意义。 展开更多
关键词 断层 水平井 稳态耦合 产能模型 径向入流剖面
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长江口北支段纳污能力分析 被引量:7
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作者 钱小娟 陈艳 顾爱辉 《水资源保护》 CAS 2012年第3期64-67,共4页
根据长江口北支水流、水质的特点和实际需要,建立二维非稳态水流-水质耦合模型,应用该模型模拟长江口北支的流场和浓度场,计算1000m污染带控制长度下长江北支自海门汤加镇至启东灯杆港江段的纳污能力,结果表明,该江段对COD的纳污能力为3... 根据长江口北支水流、水质的特点和实际需要,建立二维非稳态水流-水质耦合模型,应用该模型模拟长江口北支的流场和浓度场,计算1000m污染带控制长度下长江北支自海门汤加镇至启东灯杆港江段的纳污能力,结果表明,该江段对COD的纳污能力为3659t/a,对NH3-N的纳污能力为265t/a。 展开更多
关键词 长江口北支 二维非水流-水质耦合模型 水域 纳污能力
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多分支水平井产能模型研究
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作者 李慧 韩菲 +1 位作者 王晓飞 陈实 《内江科技》 2012年第2期14-15,共2页
目前国内外采油工程与油藏工程广泛采用的几种水平井产能预测公式,存在很多不足之处,为提高产能预测的准确性,笔者通过研究油藏渗流模型和井筒管流模型,并将这两种模型进行稳态耦合,得到一种计算水平井产能的新方法。对比前人研究的解... 目前国内外采油工程与油藏工程广泛采用的几种水平井产能预测公式,存在很多不足之处,为提高产能预测的准确性,笔者通过研究油藏渗流模型和井筒管流模型,并将这两种模型进行稳态耦合,得到一种计算水平井产能的新方法。对比前人研究的解析模型和半解析模型,新方法得到的产能更接近于实际产能。 展开更多
关键词 多分支水平井 油藏渗流模型 井筒管流模型 稳态耦合
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Existence and Regularity of Solution to a Thermally Coupled Nonstationary System
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作者 WANG Hui LI Gang +1 位作者 ZHU Jiang Dan-ni 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期512-524,共13页
In this paper, a coupled elliptic-parabolic system modeling a class of engineering problems with thermal effect is studied. Existence of a weak solution is first established through a result of Meyers' theorem and Sc... In this paper, a coupled elliptic-parabolic system modeling a class of engineering problems with thermal effect is studied. Existence of a weak solution is first established through a result of Meyers' theorem and Schauder fixed point theorem, where the coupled functions σ(s),k(s) are assumed to be bounded in the C(IR×(0, T)). If σ(s),k(s) are Lipschitz continuous we prove that solution is unique under some restriction on integrability of solution. The regularity of the solution in dimension n ≤ 2 is then analyzed under the assumptions on σ(s) ∈w^1,∞(Ω×(0, T)) and the boundedness of σ'(s) and σ″(s). 展开更多
关键词 elliptic-parabolic system EXISTENCE UNIQUENESS REGULARITY
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Tore Supra托卡马克中高功率低混杂电流驱动实验
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作者 Y.Peysson 浦江 《国外核聚变》 2002年第3期49-57,72,共10页
本文对在Tore Supra托卡马克上进行的低混杂(LH)电流驱动实验进行评述。着重强调与反应堆有关条件下高功率LH波的有效应用这一问题。在25MW·m^-2功率密度下利用设计在1000s期间耦合到4MW的新的发射器已获得了有希望的特性。天线... 本文对在Tore Supra托卡马克上进行的低混杂(LH)电流驱动实验进行评述。着重强调与反应堆有关条件下高功率LH波的有效应用这一问题。在25MW·m^-2功率密度下利用设计在1000s期间耦合到4MW的新的发射器已获得了有希望的特性。天线保护限制器上的热负荷和栅口附近电场中快电子加速度保持低水平,而平均反射系数没有超过10%。硬X射线(HXR)快电子韧致辐射层析X射线照相的满功率诊断能力使得对LH波动力学的理解有了明显的进展。LH波驱动的最快电子驱动的作用显然已得到确定。根据HXR测量,预计LH电流驱动效率是随等离子体电流增大的,在零环电压处的直接测量已证实了这一点。观察到低混杂功率吸收几乎在所有等离子体条件下都是离轴的,并且其径向宽度显然取决于天线定相条件。在全非感应放电下已确定了HXR分布和改善芯部约束开始之间的关系。业已发现由于磁剪切的某些消失而出现的这种工况是短暂的,通常在最小安全因子变得接近2时终止,从而导致大的MHD活性。实验观察和数值模拟表明通过等离子体的几次跃迁后LH功率被吸收。但是,除了环向模耦合外,可能其它机制对LH波的谱加宽有贡献。 展开更多
关键词 低混杂电流驱动 HXR ToreSupra托卡马克 高功率耦合 等离子体平衡
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Stability analysis of a hybrid flexible-rigid pipe conveying fluid
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作者 Yikun Wang Ziyang Hu +3 位作者 Lin Wang Tao Qin Mo Yang Qiao Ni 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第2期141-153,I0005,共14页
The stability and dynamical behavior of flexible and articulated rigid pipes conveying fluid have attracted the attention of many researchers in the field of fluid-structure interactions.The system of an articulated p... The stability and dynamical behavior of flexible and articulated rigid pipes conveying fluid have attracted the attention of many researchers in the field of fluid-structure interactions.The system of an articulated pipe composed of a flexible pipe and a rigid pipe is a class of hybrid flexible-rigid dynamical problems involving flow-induced vibrations.This paper establishes the governing equations of motion of a hybrid flexible-rigid pipe system based on Hamilton's principle,with the rigid pipe being hinged to the lower end of a flexible cantilevered pipe via a rotational spring.The coupling equations of motion are discretized via a Galerkin's approach.The mathematical model is validated by comparing the eigenvalue branches of a degenerated system by choosing extreme values of the parameters of the hybrid pipe with previous results.In the theoretical analysis,the critical flow velocities are calculated as a function of the stiffness of the rotational spring,mass ratio and length ratio of the rigid and flexible pipes.The unstable modes are detected from the eigenvalue branches and compared with those of a flexible cantilevered pipe.Numerical results show that the critical flow velocity is greatly influenced by several structural parameters.It is found that a small stiffness of the rotational spring tends to predict higher-mode instability,whereas a large rotational spring stiffness would generate a second-mode instability in most cases.In several system parameter spaces,the hybrid pipe may experience a transference of unstable modes with the increase of flow velocity.It is also shown that the hybrid pipe system may lose stability first in the fourth mode in some cases.Some of the fresh results obtained for the hybrid pipe system are expected to be helpful in understanding and controlling the dynamical responses of hybrid flexible-rigid fluid-conveying pipes. 展开更多
关键词 Hybrid flexible-rigid pipe Flow-induced vibration EIGENVALUE Critical flow velocity FLUTTER
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Simulation of Unsteady State Performance of a Secondary Air System by the 1D-3D-Structure Coupled Method
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作者 WU Hong LI Peng LI Yulong 《Journal of Thermal Science》 SCIE EI CAS CSCD 2016年第1期68-77,共10页
This paper describes the calculation method for unsteady state conditions in the secondary air systems in gas turbines. The 1D-3D-Structure coupled method was applied. A 1D code was used to model the standard componen... This paper describes the calculation method for unsteady state conditions in the secondary air systems in gas turbines. The 1D-3D-Structure coupled method was applied. A 1D code was used to model the standard components that have typical geometric characteristics. Their flow and heat transfer were described by empirical correlations based on experimental data or CFD calculations. A 3D code was used to model the non-standard components that cannot be described by typical geometric languages, while a finite element analysis was carried out to compute the structural deformation and heat conduction at certain important positions. These codes were coupled through their interfaces. Thus, the changes in heat transfer and structure and their interactions caused by exterior disturbances can be reflected. The results of the coupling method in an unsteady state showed an apparent deviation from the existing data, while the results in the steady state were highly consistent with the existing data. The difference in the results in the unsteady state was caused primarily by structural deformation that cannot be predicted by the 1D method. Thus, in order to obtain the unsteady state performance of a secondary air system more accurately and efficiently, the 1D-3D-Structure coupled method should be used. 展开更多
关键词 Secondary air system Unsteady 1D-3D-structure Coupling Gas turbine
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Metastability in the Spin-1 Blume–Emery–Griffiths Model within Constant Coupling Approximation
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作者 C.Ekiz 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第2期192-196,共5页
In this paper, the equilibrium properties of spin-1 Blume–Emery–Griffiths model are studied by using constant-coupling approximation. The dipolar and quadrupolar order parameters, the stable, metastable and unstable... In this paper, the equilibrium properties of spin-1 Blume–Emery–Griffiths model are studied by using constant-coupling approximation. The dipolar and quadrupolar order parameters, the stable, metastable and unstable states and free energy of the model are investigated. The states are defined in terms of local minima of the free energy of system. The numerical calculations are presented for several values of exchange interactions on the simple cubic lattice with q = 6. 展开更多
关键词 Blume–Emery–Griffiths model metastable states critical phenomena constant-coupling approximation
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Room-Temperature Steady-State Entanglement in a Four-Mode Optomechanical System
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作者 王涛 张锐 苏雪梅 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第5期596-600,共5页
Stationary entanglement in a four-mode optomechanical system,especially under room-temperature,is discussed.In this scheme,when the coupling strengths between the two target modes and the mechanical resonator are equa... Stationary entanglement in a four-mode optomechanical system,especially under room-temperature,is discussed.In this scheme,when the coupling strengths between the two target modes and the mechanical resonator are equal,the results cannot be explained by the Bogoliubov-mode-based scheme.This is related to the idea of quantummechanics-free subspace,which plays an important role when the thermal noise of the mechanical modes is considered.Significantly prominent steady-state entanglement can be available under room-temperature. 展开更多
关键词 four-mode optomechanics steady-state entanglement quantum-mechanics-free subspace
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Optimal Force Mismatch for Fluctuation-Activated Transition in a System of Two Coupled Bistable Oscillators
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作者 陈含爽 黄凤 +2 位作者 何刚 申传胜 侯中怀 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第5期575-580,共6页
We study the fluctuation-activated transition process in a system of two coupled forced bistable oscillators with a mismatch σ in the force constants. As the coupling strength μ is increased, the transition pathway ... We study the fluctuation-activated transition process in a system of two coupled forced bistable oscillators with a mismatch σ in the force constants. As the coupling strength μ is increased, the transition pathway undergoes four stages changes from a two-step process with two candidate pathways to a mixture of a two-step pathway and a one-step pathway to a one-step process with also two candidate pathways and then to a one-step process with a single pathway.Interestingly, we find that the total transition rate depends nonmonotonically on σ in the weak coupling: a maximal rate appears in an intermediate magnitude of σ. Moreover, the rate also exhibits an unexpected maximum as a function ofμ. The results are in an excellent agreement with our numerical simulations by forward flux sampling. 展开更多
关键词 fluctuation-activated transition bistable oscillator transition rate diversity
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Optical bistability based on surface plasmon coupled between a noble metal film and a metal grating involving Kerr materials
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作者 SONG Gang WU Chao +2 位作者 ZHOU YanPing YU Li XIAO JingHua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第11期2098-2103,共6页
A phenomenon about optical bistability is successfully investigated in a layered structure consisting of a silver film with Kerr medium and a silver grating sandwiched between semi-infinite linear dielectrics.This typ... A phenomenon about optical bistability is successfully investigated in a layered structure consisting of a silver film with Kerr medium and a silver grating sandwiched between semi-infinite linear dielectrics.This type of structure can lead to the optical bistability phenomena occurring in reflection and transmission.There exists an optimal thickness of the metal grating that can cut off the effect of the near-field enhancement and may have the lowest effect on conversion from surface plasmon to light.This structure can realize the functions of the beam splitter and the polarization splitter and will be essential for future classical and quantum information processing. 展开更多
关键词 surface plasmon optical bistability quantum information
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STABILIZATION OF COUPLED PDE-ODE SYSTEMS WITH SPATIALLY VARYING COEFFICIENT
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作者 LI Jian LIU Yungang 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2013年第2期151-174,共24页
The paper is concerned with the stabilization of a class of coupled PDE-ODE systems with spatially varying coefficient,via state-feedback or output-feedback.The system is more general than that of the related literatu... The paper is concerned with the stabilization of a class of coupled PDE-ODE systems with spatially varying coefficient,via state-feedback or output-feedback.The system is more general than that of the related literature due to the presence of the spatially varying coefficient which makes the problem more difficult to solve.By infinite-dimensional backstepping method,both state-feedback and output-feedback stabilizing controllers are explicitly constructed,which guarantee that the closed-loop system is exponentially stable in the sense of certain norm.It is worthwhile pointing out that,in the case of output-feedback,by appropriately choosing the state observer gains,the severe restriction on the ODE sub-system in the existing results is completely removed.A simulation example is presented to illustrate the effectiveness of the proposed method. 展开更多
关键词 Coupled PDE-ODE systems infinite-dimensional backstepping transformation spatially varying coefficient stabilization.
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