静电微电机微转子接触动力学特性分析

提出静电微电机中转子和固定轴承间相互接触的数学模型，对微尺度下的接触应力和应变 特性进行理论推导，分析静电微电机几何参数、静电力、材料特性及加载电压对接触宽度、 应力和应变特性的影响，对比研究不同工况下接触宽度、接触应力和应变的变化，并就相同 的问题进行有限元分析，探讨摩擦系数对接触区von Mises应力、应变和接触压力 的影响，结果表明有限元模拟所得接触应力和应变分布与数学 模型的解析值较为相似.     

DDA与FEM耦合法在分缝重力坝非线性分析中的应用

混凝土重力坝一般设有数条纵缝。纵缝使坝体的连续性遭到破坏，一般的有限单元法很难处理这样的不连续变形问题。本文首先阐述了DDA(Discontinuous Deformation Analysis)与FEM(Finite Element Method)耦合算法的原理，然后采用作者自行研制的DDA与FEM耦合法程序对一实际重力坝进行了详细的计算分析。重点讨论了纵缝的不同设置形式和缝宽大小对坝体变形和应力分布、坝底面接触应力分布以及坝基面应力分布的影响，为工程设计提供依据。     

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简述了多刚体系统接触及碰撞动力学的研究方法，详细回顾了考虑库仑摩擦的多刚 体系统的能量不协调、Painlev\'{e}疑难及碰撞恢复系数等该领域中难点问题的研 究进展，探讨了解决该难点问题的研究思路，指出了未来该领域的研究方向.     

滚子摩擦副弹流润滑特性及其应用──Ⅰ 有限长直母线滚子的弹流数值解

运用改进的数值方法求得了与实验结果相符的等温有限长直母线滚子的弹流数值解，与无限长线接触弹流结果相比较，揭示了润滑状态下滚子摩擦副的边缘效应和端泄对油膜分布的影响，在低速和重载时滚子的两端都几乎不能形成全膜润滑，因而有必要通过修形消除滚子端部的边缘效应．     

虚边界元法的应用及其求解方法

由弹性力学问题的虚边界元方法出发，给出若干算例，对基在接触，塑性，蠕变等非线性问题中的应用，做了进一步探讨，提出了相应的求解方案。     

有限变形粘弹性接触的数学规划方法

研究有限变形粘弹性物体间的接触问题，同时考虑了刚体位移和摩擦等因素，导得该问题数学规划解法的标准形式，极易利用现有算法求解。     

微重时卧圆柱内静液面方程与数值计算

由力学平衡方程导出了微重时卧圆柱内静液面方程，推出了边界接触角条件，使用Ｒｕｎｇｅ Ｋｕｔａ法在计算机上得出了数值结果，绘出了静液面形状，并对结果进行了分析．     

不同材料交界面上接触应力的有限元分析

工程中有许多不同材料组成的结构。对这类复合结构，正确计算材料交界面上的接触应力是非常重要的。通常的位移有限元法得到的应力是不连续且欠准确的。本文提出了一种新的用于不同材料交界面处的接触单元。应用虚位移原理和结合考虑材料交界面上的约束条件，文章建立了接触单元的刚度矩阵和等效荷载向量。该单元具有算法简单，程序容易实现的优点。计算实例证实了该单元的实用性和可靠性。     

Inter-contact force analysis of impacted disk assembly by dynamic caustics

The caustic method was utilized to study the contact force transmission in disk assemblies under impact load. The mapping equations were obtained based on the first invariant of the stress components in the disk subject to a normal concentrated force, and a characteristic dimension of the maximum size in the caustic curve was proposed to evaluate the contact force between the disks. Transient patterns of the caustic shadows were recorded by means of a high-speed camera of off-focus imaging, then the histories of the inter-contact forces among the disks were obtained with respect to the conditions of different masses and heights of the falling hammers. The influence of the impact loading and impulsive velocity was analyzed with respect to the force responses of the disk assembly, the double-peak phenomenon with comparison to the initial masses, and the energy dissipation of the systems under impact of different momentums. The project supported by the National Natural Science Foundation of China (10125211)     

Computerized Developments in Design,Generation, Simulation of Meshing,and Stress Analysis of Gear Drives

The paper represents new computerized developments in design, generation, simulation of meshing, and stress analysis of gear drives. The main contents of the paper are: (i) application of a predesigned parabolic function of transmission errors for reduction of noise, (ii) computerized simulation of noise caused by transmission errors, (iii) modification of the basic algorithm of tooth contact analysis, and (iv) application of approaches developed for enhanced design and simulation of meshing of the following gear drives: (a) spiral bevel gear drives, (b) face-gear drives (including an approach for grinding), and (c) modified helical gear drives. The developed theory is illustrated with numerical examples.