DNA结构动力学计算机仿真算法和图形后处理

利用Kirchhoff弹性杆模型的动力学比拟技巧,建立了描述超长弹性杆曲面形成的常微分/代数方程组,将方程组表示为Hamilton方程的形式,并利用辛算法给出了曲面方程的数值解法,并给出了超长弹性杆的图形处理的计算实例。     

水射流主动补偿细长轴切削加工分析

针对低刚度细长轴在加工过程中因切削力而产生的回弹变形误差,提出了一种水射流辅助支撑细长轴加工的新型加工方法,建立了细长轴切削加工变形补偿模型,并分析细长轴在有无水射流支撑作用下的变形情况。最后,对细长轴在有无水射流辅助支撑作用下进行了实验对比分析。结果表明,水射流辅助支撑可很好的减小细长轴加工误差,为提高细长轴的质量提供理论指导。     

联轴器扭转刚度对潜油电泵细长串联轴系扭振特性的影响研究

为解决在满负荷、长周期运行工况下潜油电泵下保护器轴易断裂的问题,以潜油电泵细长串联轴系为研究对象,分析联轴器扭转刚度对细长串联轴系扭振特性的影响.采用DyRoBeS软件构建细长串联轴系扭振模型,分析轴系扭振特性,结合扭转振型与模态扭应力分布,确定轴系下保护器轴退刀槽为危险截面,研究联轴器扭转刚度与该危险截面扭应力的关系...     

Potential improvements of the presently applied in-service inspection of wheelset axles

Wheelset axles are safety relevant components because they are subject to high dynamic and static loads during operation. Therefore, they have to undergo periodic non-destructive examination to find potential defects before they can lead to failure. Minimizing the risk of fatigue failure for 3.5 million axles, potentially in service in Europe, was the objective of the 3.5 years R&D project EURAXLES which ended in April 2014. EURAXLES aimed to propose a global concept approach for axles design, production, and maintenance. An important objective within Work Package 5 was the analysis of the present status of in-service inspections. The strengths and weaknesses of the presently applied inspection systems and practices were evaluated with the aim to identify potential improvements provided by new technologies. That evaluation was firstly based on the results of a questionnaire which was distributed to the main European railway operators with the request to describe the testing procedures and equipment applied in their maintenance facilities. Secondly, the results of benchmark tests with presently applied ultrasonic inspection equipment were exploited for the analysis. These tests were performed at hollow axles and solid axles with implemented artificial defects.     

Probabilistic fatigue assessment for railway axles and derivation of a simple format for damage calculations

This paper describes a procedure for the determination of railway axle risk of fatigue failure under service loading for a simple fatigue assessment compliant to modern structural recommendations.After an initial review of reliability assessment under fatigue, a fully probabilistic approach is outlined, whose input data for the fatigue damage obtained with the EURAXLES project are briefly summarized. Then, a series of Montecarlo simulations was carried out in order to determine the maximum allowable stress for a given axle made of EA4T and EA1N under service conditions identified by different load spectra from the literature.Results have been obtained in terms of a safety factor for damage calculations that allows designers to adopt a simple semi-probabilistic approach for designing axles for a target reliability against fatigue. The application of this procedure to a railway axle then shows how safety factors should be have to be further increased for taking into the prospective presence of impact damages.     

铣床加工花键之方法改进

花键轴是电解天车上扭拔机构中的重要零件之一,起到提供扭矩和导向的作用。为使花键轴加工时保证精度的前提下提高效率,并能成批量的进行加工。通过对该机床的构造特点及工件外形的分析比对,对其在加工花键时的加工及装卡方法提出了改进,并制作了一套可以有效提高工作效率和保证产品质量的制具。     

普通车床加工长螺纹

针对长螺纹2种常规加工方法中存在的问题,介绍了一套将跟刀架铸铁棒滑动摩擦改进为跟刀架轴承滚动摩擦的方法,增强了跟刀架的刚度,满足工件刚度要求,消除弯曲、摆动和铸铁棒跟刀架的磨损,并能更多地将径向力转化为轴向力。同时配合以最佳的刀具几何参数、切削用量等一系列有效措施,提高了长螺纹轴的刚性,满足了加工要求,大大提高了工效。     

高耸塔台结构风振动力响应分析

采用ANSYS软件建立了高耸塔台的三维有限元模型,在导出其刚度矩阵和质量矩阵的基础上,建立了具有三维有限元模型力学性能的二维多自由度体系,采用快速傅利叶变换（FFT）进行了随机风场的仿真,用Wilson-θ法对其进行了动力响应分析,分析表明,塔台明室加速度响应峰值为0.041 35 m/s2,小于规范规定的容许峰值,满足人体舒适度要求。     

长丝杠加工方案设计实践

根据零件的技术特性,制定了合理的加工方案。阐述了具体加工工艺内容,制作芯轴,解决了细长零件加工难的问题。     

钢骨混凝土长柱稳定承载力研究试验设计

从试件设计、试验结果测试两个方面讨论了钢骨混凝土长柱稳定承载力研究试验的具体实施细节,并提出了该类型柱稳定承载力理论分析模式.