强震区山谷灰场排渗设计

从沉积粉煤灰颗粒分布，渗流特点和石庄头灰场三维渗流有限元计算，揭示初期透水坝排渗设施所降低的浸润线，只能使粉煤灰坝处于静力稳定或较低地震区的抗震稳定，初期透水坝排渗设施和加涡山沟贴板反滤层设施，能较大幅度降低浸润线，使粉煤在坝处于强震稳定状态。     

SIMULINK在反应堆温度控制系统仿真中的应用研究

采用SIMULINK软件对核电站反应堆温度控制系统进行建模和仿真,着重介绍了建模方法以及技巧,并将仿真结果与实际数据进行了比较,验证了模型的正确性,此种仿真方法可在其他动态控制领域进行类似的应用。     

基于声学黑洞现象的结构波操纵及其在振动噪声控制中的应用

Acoustics Black Holes(ABH)effects can be achieved through manipulations of bending wave propagation inside a thin-walled structure with its thickness tailored according to a power-law variation.In doing so,the phase velocity of the bending wave gradually reduces alongside thickness thinning,eventually to zero in the ideal scenario at the wedge tip/indentation center,resulting in zero wave reflection and high energy concentration within a small localized area.The phenomenon attracts increasing attentions as a promising passive vibration control method because vibration energy can be channeled and only a very small amount of damping material is required within the energy focalization region to achieve efficient damping to flexural waves.In addition,the wave slowing phenomenon allows the creation of a subsonic region inside a supersonic structure,thus reducing the its overall sound radiation efficiency.These unique features point at a great potential of the ABH technology for various applications such as vibration control,sound radiation reductions and energy harvesting.This talk summarizes some of the recent progress made in the study of the ABH.Topics cover the semi-analytical modelling of the ABH structures;design and analysis of a double-layer compound ABH beam for improved static and dynamic properties;combination of locally resonant and Bragg scattering for broadband stopband creation as well as some examples of ABH for vibration and sound noise control applications.     

XDPS系统慢信号保护功能块运行分析

本文讲述了上海新华DCS系统慢信号保护功能块在温度保护逻辑中功能块参数设置注意事项,避免温度保护误动作而造成重要辅机跳闸。     

二维声学黑洞对弯曲波的能量聚集效应

声学黑洞(Acoustic Black Holes,ABH)效应是利用结构厚度以一定幂函数形式减小,致使弯曲波的相速度逐渐减小而实现能量逐渐聚集,理想情况下弯曲波波速减小为0从而无法传递到结构边缘,也就不会发生反射。声学黑洞效应使得结构产生高能量密度区域,因此能高效应用于能量回收和振动噪声控制。为了研究二维声学黑洞结构具有弯曲波能量聚集效应,运用有限元分析软件ABAQUS建立了二维声学黑洞模型,从时域上研究弯曲波在声学黑洞区域的传播过程,结合有限元数值结果与振动功率流的结果分析弯曲波能量聚集过程。最后通过激光超声实验系统对二维声学黑洞中弯曲波传播过程进行成像与分析,实验结果验证了二维声学黑洞结构对弯曲波能量的聚集效应。     

碳氮共渗剂

对于表面要求硬而耐磨、芯部要求有良好的韧性、整体有满意的疲劳寿命的零件 ,最好采用低碳钢或经碳氮共渗处理过的低合金钢。（１）共渗剂欲进行碳氮共渗 ,首先应解决共渗剂的问题。共渗剂的配方各不相同 ,常用的有氨 煤油、甲醇 尿素 丙酮 ,以及三乙醇氨等几种。使用这些共渗剂 ,往往存在下面的问题 :或是附加设备多 ,或是原料供应困难 ,或是出现黑色组织 ,或是氮浓度太低 ,或是价格昂贵等等。因此必须研制简便而可靠的碳氮共渗剂。由于尿素在工业纯甲醇或酒精中的室温饱和溶解度分别为１５ %和１０ % ,所以直接采用此种溶液作共渗剂难…