山岭隧道涌水量预测方法分类及相关因素分析

准确预测隧道涌水量能有效减少隧道病害,保护生态环境,科学指导隧道的设计与施工,而如何正确选择和应用预测方法,是准确预测的前提条件。通过广泛调研,在总结分析各类涌水量预测方法的原理和适用范围基础上,以六盘山隧道某断面为例,深入探讨了围岩渗透系数、洞室尺寸、地下水位净高变化、注浆圈厚度、注浆水平和衬砌抗渗等级等因素对隧道涌水量的影响,重点指出各类解析方法的局限性和适用条件,突出了注浆水平在实际工程中的作用,并建议山岭公路隧道衬砌抗渗等级不宜小于S8。     

160 km/h高速货车转向架的研制

根据高速货车转向架的运用要求和运用条件,确定了160km/h高速货车转向架的主要技术参数;提出了整体焊接构架式有摇枕转向架的结构形式,介绍了其主体结构情况;结合转向架静强度和疲劳试验、线路动力学试验结果,得出了转向架设计是较为成功的结论。     

米轨客车迫导向转向架动力学性能研究

建立了米轨迫导向转向架客车的动力学模型，提出了迫导向机构的等效处理方法，以研究迫导向转向架导向机构参数对客车动力学性能的影响，计算结果表明，增大迫导向机构刚度和增益有利于提高蛇行失稳临界速度和曲线通过能力；连杆间铰链的间隙则对迫导向机构的性能有明显不利的影响。     

抗蛇行减振器对机车运行品质的影响

借助虚拟样机技术和ADAMS/Rail软件,针对国内某型电力机车建立了机车系统详细的动力学仿真模型。利用动力学仿真工具,对抗蛇行减振器的特性进行分析,研究其参数变化、失效等对机车运行性能的影响,得出其规律。     

轮对纵向振动与机车车辆相关问题研究

借助于1个整车模型,观察到轮对相对于构架实际上始终存在纵向振动,而且这种振动在某些中低速范围内有可能发展为强烈的共振;另一方面,轮对相对构架的强烈振动,也可能成为车轮非正常磨耗即剥离以及某些波长轨道波磨的一个重要因素。本文对轮对纵向共振的形成条件进行了分析,给出了近似计算判据,并对车辆主要参数对共振的影响进行了分析,最后给出了一种抑制纵向振动的建议方案。     

高性能机车转向架的研发

论述了高性能机车转向架设计理念 ,并提出了从结构设计、参数优化、动力学性能预测 3方面出发开发高性能机车转向架的具体措施 ;以 2 0 0km/h交流传动电力机车转向架的研发为例 ,介绍了高性能机车转向架设计理念的具体应用情况及实际效果。     

减轻列车轮轨横向动力作用的技术措施

基于铁道车辆-轨道耦合动力学理论及仿真分析系统，分析了机车车辆悬挂参数、结构参数及轨道结构参数对轮轨横向相互作用的影响，在此基础上提出了降低轮轨横向动力作用的技术措施：（1）一系水平定位刚度（纵向和横向刚度）对轮轨横向动力作用影响较大，刚度值选取的基本设计原则是，在充分满足运动稳定性的前提下，尽可能降低刚度值；（2）二系水平（包括纵向和横向）刚度对轮轨横向动力作用影响不明显，设计时，应更多地考虑机车车辆的平稳性；（3）簧下质量对轮轨横向动力作用影响较大，较小簧下质量，将使轮轨横向动力作用得到显著的降低；（4）较低的扣件横向刚度、扣件垂向刚度及道床横向刚度等参数值将有利于降低轮轨横向动力作用。     

Dynamic analysis of a pantograph-catenary system using absolute nodal coordinates

The dynamic interaction between the catenary and the pantographs of high-speed trains is a very important factor that affects the stable electric power supply. In order to design a reliable current collection system, a multibody simulation model can provide an efficient and economical method to analyze the dynamic behavior of the catenary and pantograph. In this article, a dynamic analysis method for a pantograph-catenary system for a high-speed train is presented, employing absolute nodal coordinates and rigid body reference coordinates. The highly flexible catenary is modeled using a nonlinear continuous beam element, which is based on an absolute nodal coordinate formulation. The pantograph is modeled as a rigid multibody system. The analysis results are compared with experimental data obtained from a running high-speed train. In addition, using a derived system equation of motion, the calculation method for the dynamic stress in the catenary conductor is presented. This study may have significance in providing an example that a structural and multibody dynamics model can be unified into one numerical system.     

半主动悬挂的横向和垂向阻尼系数对车辆动力学性能的影响

利用天棚控制原理和SIMPACK动力学软件建立了具有二系横向和垂向半主动悬挂车辆模型,分析在不同的半主动悬挂横向和垂向阻尼系数下,车体平稳性指标、构架加速度、轮对冲角和磨耗指数的变化情况,结果表明动力学性能之间存在多处相互矛盾的地方,在选择半主动悬挂横向和垂向阻尼系数时应合理安排,充分协调相互矛盾的动力学性能.     

On the dense water spreading off the Ross Sea shelf (Southern Ocean)

In this study, current meter and hydrological data obtained during the X Italian Expedition in the Ross Sea (CLIMA Project) are analyzed. Our data show a nice agreement with previous data referring to the water masses present in this area and their dynamics. Here, they are used to further analyze the mixing and deepening processes of Deep Ice Shelf Water (DISW) over the northern shelf break of the Ross Sea. In more detail, our work is focused on the elementary mechanisms that are the most efficient in removing dense water from the shelf: either classical mixing effects or density currents that interact with some topographic irregularity in order to drop to deeper levels, or also the variability of the Antarctic Circumpolar Current (ACC) which, in its meandering, can push the dense water off the shelf, thus interrupting its geostrophic flow. We also discuss in detail the (partial) evidence of dramatic interactions of the dense water with bottom particulate, of geological or biological origin, thus generating impulsive or quasi-steady density-turbidity currents. This complex interaction allows one to consider bottom particular and dense water as a unique self-interacting system. In synthesis, this is a first tentative analysis of the effect of bottom particulate on the dense water dynamics in the Ross Sea.