搜索结果: 16-30 共查到“知识库 应用力学”相关记录821条 . 查询时间(3.968 秒)
圆筒容器内起旋和降旋过程中分层液体混合现象
平面激光诱导荧光 液体混合 起旋过程 降旋过程
2016/11/1
针对旋转圆筒容器内的两种分层流体，应用平面激光诱导荧光与高速摄影技术对互溶与不互溶液体进行了实验研究.结果表明，上下层液体密度梯度与黏度梯度方向是产生界面不稳定的关键因素.当二者的梯度方向相同时，起旋过程不会发生剧烈混合，降旋过程中轻流体会冲击重流体；当二者的梯度方向相反时，起旋过程中形成抽吸效应，其后期发生界面破碎，降旋过程中重流体冲击轻流体.在旋转的3个过程中，降旋过程对混合的作用最大，无论梯...
Towards Quantifying Complexity with Quantum Mechanics
Towards Quantifying Complexity Quantum Mechanics
2016/1/22
While we have intuitive notions of structure and complexity, the formalization of this intuition is non-trivial. The statistical complexity is a popular candidate. It is based on the idea that the com...
相分离过程的离散Boltzmann方法研究进展
相分离 离散Boltzmann方法 非平衡效应 相畴增长
2016/11/1
概述相分离过程的离散Boltzmann方法研究进展.这部分研究内容，根据系统的成分，可分为单介质的两相分离和多介质的相分离；根据物理建模，可分为基于传统流体模型的LBM（lattice Boltzmannmethod）数值模拟和相分离系统的动理学建模与模拟；根据研究的侧重点，可分为方法（模型）研究和相分离过程研究.离散Boltzmann模拟所提供的非平衡行为特征为区分相分离的两个不同阶段提供了一个...
接触与摩擦对行走影响的仿真与实验研究
被动行走 足地接触
2016/4/18
主要通过实验测量的方法研究被动行走中的足地接触过程,得到接触过程对行走稳定性的影响,对实验测量结果与仿真计算结果进行了对比,得到了较好的吻合效果.
关于地月系统的拉格朗日点
万有引力 地月轨道 拉格朗日点 希尔曲线族
2015/12/17
解释拉格朗日点的力学概念.计算地月系统的拉格朗日点.根据希尔曲线族的几何特征对拉格朗日点的稳定性给出直观的解释.
研究了载体位置、姿态均不受控的情况下，系统参数不确定的柔性关节空间机器人轨迹跟踪的控制问题.结合系统动量、动量矩守恒关系，利用拉格朗日法推导出系统的动力学模型.为减小系统柔性关节对系统控制精度的影响，采用关节柔性补偿器来等效降低系统关节的柔性.再借助奇异摄动法，针对系统参数不确定的情况，设计了柔性关节空间机器人基于干扰观测器的退步自适应滑模控制方案.该方案不需要对系统惯性参数进行线性化处理，控制器...
基于剪切修正GTN模型的金属弹性退化机理研究
压痕法 损伤 有限元模拟
2016/4/18
许多金属材料在进行显微或宏观压入测试时,测得的弹性模量会随着压入深度的增大而不断降低.考虑到在压痕测试过程中金属材料并不产生明显的裂纹,这种性能退化应是由材料的损伤引起.然而,经典损伤理论认为以受压和受剪为主的压入变形不会引起材料软化和损伤.本文结合剪切变形下材料损伤的萌生和演化机理,对经典的GTN(Gurson-Tvergaard-Needleman)模型进行了修正,对压入测试进行了有限元模拟....
Non-linear modal interactions in the oscillations of a liquid drop in a gravitational "eld
Liquid drop Modal interactions Bifurcations
2015/8/27
Non-linear modal interactions in the dynamics of a vibrating drop are examined. The partial di!erential equations governing the drop vibrations are formulated assuming potential #ow and incompressibil...
A Bifurcation Analysis of the Quadratically Damped Mathieu Equation and Its Applications to the Dynamics of Submarine Towed-Array Lifting Devices
Bifurcation Analysis Quadratically Damped Mathieu Equation Applications Dynamics Submarine Towed-Array Lifting Devices
2015/8/27
This work concerns the dynamics of towed array lifting devices (LFDs), which help to maintain the position of a tow line being dragged behind a vessel.
Bifurcations in a Mathieu equation with cubic nonlinearities:Part II
Mathieu equation Bifurcations Averaging
2015/8/27
We found that a degenerate bifurcation point occurs in the resulting slow flow and some of the bifurcations near this point were looked at. In this work we present additional results concerning the bi...
Center manifold analysis of a DDE model of gene expression
Delay DDE Center manifold Hopf bifurcation Gene transcription
2015/8/27
We use center manifold theory to analyze a model of gene transcription and protein synthesis which consists of an ordinary differential equation (ODE) coupled to a delay differential equation (DDE). T...
Perturbation analysis of entrainment in a micromechanical limit cycle oscillator
Resonance MEMS Bifurcation Perturbation
2015/8/27
We study the dynamics of a thermo-mechanical model for a forced disc shaped, micromechanical limit cycle oscillator.The forcing can be accomplished either parametrically, by modulating the laser beam ...
Trigonometric simplification of a class of conservative nonlinear oscillators
Nonlinear normal modes Stability Trigonometrification
2015/8/27
Thispaperdealswithaclassofconservative nonlinear oscillators of the form ¨ x(t) + f (x(t)) = 0,where f (x) is analytic. A transformation of time fromt to a new time coordinate τ is defined such that p...
2:1 Resonance in the delayed nonlinear Mathieu equation
Averaging Degenerate Hopf Delay Nonlinear Mathieu Parametric excitation
2015/8/27
We investigate the dynamics of a delayed nonlinear Mathieu equation:¨ x + (δ + εα cost)x + εγx 3 = εβx(t − T) in the neighborhood of δ = 1/4. Three different phe-nomena are combined in this syst...