Study on hydrodynamic vibration in fluidic flowmeter

The characteristics of the fluidic flowmeter,which is a combination of impinged concave wall and bistable fluid amplifier,is investigated by experimental studies and numerical simulations. The numerical approaches are utilized to examine the time dependent flow field and pressure field inside the proposed flowmeter. The effect of varying structural parameters on flow characteristics of the proposed fluidic flowmeter is investigated by computational simulations for the optimization. Both the simulation and experimental results disclose that the hydrodynamic vibration,with the same intensity,frequency and 180° phase shift,occurs at axisymmetric points in the feedback channel of the fluidic flowmeter. Using the structural combination of impinged concave wall and bistable fluid amplifier and differential signal processing technique,a novel fluidic flowmeter with excellent immunity and improved sensibility is developed.     

含卤素基团振动波数关系

本文从大量数据中总结出:组成及结构类似的含卤素基团的振动波数基本上按F、Cl、Br、I的顺序降低     

二硫代氨基甲酸汞配合物Hg2(S2CNR2)4几何异构体的量子化学研究

采用密度泛函理论(B3LYP)方法,在SDD和6-31G(d)混合基组水平上,对二硫代氨基甲酸汞配合物Hg2(S2CNR2)4进行了从头计算研究,计算出了两种几何异构体.一种结构是C2点群,另一种是Ci点群.进一步计算并对比了两种结构化合物的结构、能量、原子电荷布局规律、一些前沿分子轨道组成,以及化合物的振动光谱.振动频率结果分析,均未出现虚频,说明两种结构都是稳定结构,再结合能量数值分析,两种配合物的能量几乎相等,所以从理论上能得出在实验上都可以合成这两种结构的配合物的结论.     

求解一类特征值反问题的新方法

提出了求解一类特征值反问题的新方法 ,应用此法确定了发电机组轴系扭振系统的模型参数。此法力学概念明确 ,易于操作     

固体热胀机理的统计物理分析

考虑原子振动的非简谐效应，从原子间相互作用势能入手，运用玻尔兹曼统计原理，推出了原子间距的变化与温度的关系式，并导出了固体的线胀系数，分析结果与实验是相符的。     

阶梯波逆变电路的分析与设计

本文分析一种阶梯波逆变电路,它利用六个可控硅的不同导通次序,获得十二个阶梯波,它的最低次谐波为十一次,而且它的谐波次数与导通角无关。文中导出了这一波形的阶梯高度、变压器线匝和换流元件的优化设计。     

扭转振动柱体的理论分析

对扭转振动的柱体进行了受力分析和理论分析 ,为工程应用提供一参考     

井点降水管成活率测试仪的研制与应用

用于检测井点降水管是否成活，采用压电式加速度传感器，以振动测量作为基本设计原理，克服环境干扰等因素，研制和开发了高灵敏度，低噪声的井点降水管成活率测试仪器。实用效果很好。     

Analytic Solution to Nonlinear Dynamical Systemof Dragon Washbasin

Based on phase-plane orbit analysis, the mathematical model of piecewise-smooth systems of multidegree-of-freedom under the mode coordinate is established. Approximate analytical solution under the physical coordinate of multi-degree-of-freedom self-excited vibration induced by dry friction of piecewise-smooth nonlinear systems is derived by means of average method, the results of which agree with those of the numerical solution. An effective and reliable analytical method investigating piecewise-smooth nonlinear systems of multi-degree-of-freedom has been given. Furthermore, this paper qualitatively analyses the curves about stationary amplitude versus rubbing velocity of hands and versus natural frequency of hands, and about angular frequency versus rubbing velocity of hands. The results provide a theoretical basis for identifying parameters of the system and the analysis of steady region.     

确定振动周期的几种途径

振动是典型的运动形式,周期是描述振动的重要特征量,确定振动的周期是分析和讨论振动的重要环节之一.确定振动周期有以下几种途径：用势能曲线分析和确定;用相曲线分析确定;用函级近似法分析;用量纲法分析.