振膜阻尼式料位器的原理及应用

本文所述的料位器是利用振动阻尼的原理研制的。其外形为圆柱形,它是由振动膜(用金属薄板制作)、驱动器(也是换能器)、电子电路等组成。其特点是:感应面(振动膜)是一个与外壳镶为一体的金属平面。安装使用时即可探入设备内部,也可与设备内壁成一平面,不受湿度、粉尘、污物的影响。经特殊加工可应用于特殊环境,检测不同物料的定点位置。通过在大连第一和第三粮库的烘干塔上使用表明,用振动阻尼的原理制作的料位器,在复杂恶劣的环境中检测粉粒物制的定点位置,性能稳定可非。是现已采用的料位器所不能比拟的。     

Prediction of vibrations induced by trains on line 8 of Beijing metro

This paper mainly discusses the problem of ground-borne vibrations due to the planned line 8 of Beijing metro which passes under the National Measurement Laboratory. A lot of vibration sensitive equipments are placed in the laboratory. It is therefore necessary to study the impact of vibrations induced by metro trains on sensitive equipments and important to propound a feasible vibration mitigation measure. Based or1 the coupled periodic finite element-boundary element （FE-BE） method, a 3D dynamic track-tunnel-soil interaction model for metro line 8 has been used to predict vibrations in the free field induced by trains running at variable speeds between 30 km/h and 80 km/h. Four types of track structures commonly used on the Beijing metro network have been considered： （1） high resilience direct fixation fasteners, （2） Vanguard fasteners, （3） a floating slab track and （4） a floating ladder track. For each of these track types, the vibration isolation efficiency has been compared. The results of the numerical study can be used to predict vibrations in nearby buildings and to decide upon effective vibration countermeasures.     

Method of analyzing vibration characteristics of armature system of hermetically sealed electromagnetic relay

Published research is minimal on vibration characteristics of hermetically sealed electromagnetic relay (EMR) ex- posed to mechanical environment. The vibration characteristics of armature system, link contact system with electromagnetic system will cause EMR malfunction. The nonlinear dynamics model of armature systems was studied by considering electro- magnetic attraction force and opposite mechanical force in this paper. Angular displacements of armature under different sinu- soidal vibration conditions are solved in order to obtain the failure mode result from armature system. Vibration tests showed the presented analyzing method is suitable for EMR. The conclusions are instructive for increasing vibration resistance of armature systems of EMR, and are significant for reliability design of switch apparatus.     

管线振动的计算分析

该文根据连续体振动理论,对某二氧化碳吸收管线的振动问题进行了深入的分析。通过实地测量建立管线的计算模型,算出管线现有约束情况下的固有频率和振型。同时,模拟若干种不同的约束条件进行计算,最终找出了解决管线振动的根本方法。     

基于HP35670A的皮带通廊振动测试系统

根据某焦化厂输煤皮带通廊的工作振动情况,建立了基于HP35670A的相应振动测试系统,并通过对该振动测试系统的相应标定,实现了对该皮带通廊的准确测试.     

轨道交通振动中的人工边界问题研究

随着城市化的发展,轨道交通系统导致的振动对环境的影响已日愈引起人们的关注。采用粘性边界条件对振动波在土体中传播问题进行了研究。利用ANSYS软件建立轨道结构和轨下土体的计算模型,将计算得到的轨道结构基础反力的数据输入土体模型,计算土体的动力响应,得到振动波在土体中的传播规律。     

参量振动与参量谐振

本文论述了参量振动的性质、参量谐振的条件及其在体育运动中的表现形式,分析了在体操吊环动作中如何运用和控制这一运动形式以建立合理的的竞技动作结构。     

波纹度同轴承振动关系的试验研究

本文以D80029型轴承为研究对象,应用逐步回归方法,对内圈沟道波纹度同轴承振动的关系进行了试验研究和统计分析。在此基础上得出了具有一定理论和实践意义的几点结论。     

多转速下曲轴模态分析对比

在计算曲轴频率和振型过程中,针对曲轴模态分析时一直采用的是自由模态,考虑由旋转产生离心力对曲轴频率和振型的影响,计算出多种转速情况下的频率和振型,并进行比对,充分说明曲轴在实际工作过程中产生的振动情况,结果更加符合实际情况。     

A comparative study of optimal linear controllers for vibration suppression

The performance enhancement of dynamic systems is accomplished by the application of active control components. Control strategies are derived to accomplish the task. Among the various control strategies, those that are designed to minimize a specified cost function while satisfying the necessary system constraints are referred to as optimal controllers. An important constraint is the amount of power and energy consumed by the control device. In this paper, the effect of optimal control strategies on the power and energy requirement of control devices is investigated.