采用有限元和边界元的算法,对薄板采用不同的加筋及条形阻尼的处理方式进行了仿真计算。结果表明:薄板采用单向及双向加筋的处理方式,能有效减小结构的模态密度,降低低频结构声辐射,但对于中高频段的结构声辐射并没有起到降低的作用;通过加单向和双向条形阻尼的处理方式,能在全频段内有效降低结构声辐射,但由于整体结构刚度较小,其降低结构声辐射的效果有限;而薄板采用混合加筋及条形阻尼的处理方式,其降噪效果最为明显。

By using finite element method and boundary element method,the simulation calculation of the plate based on different stiffeners and damping strips was performed in this paper.The results shows that the plate based on biaxial and uniaxial stiffeners can decrease the modal density of the structure and reduce the low frequency structure acoustic radiation effectively,but don''t have an effect on high frequency struc-ture acoustic radiation;the plate based on biaxial and uniaxial damping strips can reduce the structural a-coustic radiation in the whole frequency band,but due to the weak stiffness,the effectiveness of reducing the low frequency structure acoustic radiation is limited;but for the plate based on stiffener and damping strips,the noise reduction effect is the most obvious.

考虑输电线路弧垂、杆塔、绝缘子以及线路下方房屋等物体的特高压直流输电线路离子流场计算是三维电磁场数值计算问题，将该问题简单的等效为二维计算问题会导致所关注物体周围电磁参数求解存在较大的误差。该文基于现有的三维上流有限元理论，提出改进算法，采用新型的迭代收敛控制技术，保证了迭代收敛过程的稳定性，采用新的上流有限单元寻找方法，极大提高了程序的计算效率。该文计算了三维同轴圆柱电极间离子流场，数值仿真结果与解析解进行对比，验证了三维改进上流元法的有效性以及效率。对直流试验线路下方房屋模型附近的离子流场进行计算，计算结果与试验数据进行对比，计算方法得到了很好的验证。对特高压输电线路下方走廊附近人体模型表面电场强度进行计算，计算结果表明，相比静电场情况，人体表面电场强度得到了显著的提高。该应用表明改进三维上流元法可以有效地解决三维大规模离子流场计算问题。

The ionized field of the high-voltage direct current (HVDC) transmission line is a 3-D Electromagnetic field when considering the influence of the lines sag, towers, insulators and buildings under the transmission line. Simplifying the problem by solving a 2-D ionized field would lead to a large error of the physical quantities around the object of interest. In this paper, improved 3-D upwind finite element method (upwind FEM) was achieved based on the existing theory. An adaptive iterative controlling factor was introduced to guarantee the rapid convergence of the solving procedure. A new method to find the upwind element was used to improve the computational efficiency. The ionized field of a 3-D coaxial cylindrical electrode was computed to testify the validity and efficiency of the method. The ionized field around the room model under the DC test line was calculated, and compared with the measurement results, and the calculation method was well validated. The electric field on the

转盘轴承实验台是一种根据转盘轴承工作特点设计的专用实验设备。本文采用Simulink软件中的SimMechanics模块搭建实验台机械结构的仿真模型。仿真模型是在有限元计算的基础上,将实验台结构简化为线性弹簧。仿真模型中的转盘轴承采用Zupan等提供的解析法简化。通过滚珠最大应力验证仿真模型结果的正确性,参照标准是美国国家可再生能源实验室提供的经验公式。SimMechanics仿真结果与经验公式、有限元模型结果比较,误差在10%以内,误差可以接受。SimMechanics仿真模型的精度不及有限元模型,但仿真模型实现了机械系统与控制系统在同一仿真环境中搭建,并且仿真模型的计算成本远小于有限元模型。

Wheel bearing test bench is a special experiment equipment based on the work features of wheel bearing. This paper uses SimMechanics module of Simulink software to build bench mechanical structure simulation models. The simulation model simplifies the bench to a linear spring on the basis of finite element method. The wheel bearing of simulation model uses analytical method provided by Zupan. The correctness of simulation results is validated by balls maximum stress, the reference standard is the empirical formula provided by U.S. National Renewable Energy Laboratory. Compared to SimMechanics simulation results, empirical formula and finite element model results, the error is acceptable when less than 10%.

应用MSC.Marc软件建立三维有限元模型，对某异形产品的拉深过程进行模拟仿真。介绍了基于有限元仿真复杂拉深件坯料尺寸设计流程和方法。

The simulation process of drawing for an abnormity product by using software MSC. Marc is studied, 3D elastic plastic model is built. The designing process of blank dimensions by finite element simulation and the method is studied.

基于有限元法对曲轴应力试验边界条件进行分析,得到不同试验边界条件对曲轴应力分布的影响规律。通过应力试验与有限元仿真对比分析可知,有限元仿真可准确地预测曲轴应力试验结果,达到校核曲轴强度的目的。基于得到的影响规律进行曲轴应力试验非标支撑的设计,通过原机组合结构与试验组合结构的有限元仿真对比分析,验证了非标支撑设计的合理性。

The influences of boundary conditions for crankshaft stress test were analyzed based on finite element method (FEM ) and the influencing rules of crankshaft stress distribution were acquired under different boundary conditions .It was found that the FEM could predict the crankshaft stress accurately by comparing stress test with FEM simulation ,realizing the aim of crankshaft strength check .The non-standard bracing design of crankshaft stress test was carried out based on the ac-quired influencing rules and the design reasonability was verified through the comparison and analysis of original and test com-posite structures .