基于PLC的饮料CIP清洗控制系统

CIP（Cleaningin Place）清洗主要是对罐体、管道、泵，并在密闭的回路中进行循环清洗、消毒的控制系统。从生产工艺及节约能源等控制要求入手，阐述使用S7-200及人机介面OP170B实现控制要求及过程监控的应用。     

CFD modeling and experimental verification of oscillating flow and heat transfer processes in the micro coaxial Stirling-type pulse tube cryocooler operating at 90–170 Hz

This paper presents the CFD modeling and experimental verifications of oscillating flow and heat transfer processes in the micro coaxial Stirling-type pulse tube cryocooler (MCSPTC) operating at 90–170 Hz. It uses neither double-inlet nor multi-bypass while the inertance tube with a gas reservoir becomes the only phase-shifter. The effects of the frequency on flow and heat transfer processes in the pulse tube are investigated, which indicates that a low enough frequency would lead to a strong mixing between warm and cold fluids, thereby significantly deteriorating the cooling performance, whereas a high enough frequency would produce the downward sloping streams flowing from the warm end to the axis and almost puncturing the gas displacer from the warm end, thereby creating larger temperature gradients in radial directions and thus undermining the cooling performance. The influence of the pulse tube length on the temperature and velocity when the frequencies are much higher than the optimal one are also discussed. A MCSPTC with an overall mass of 1.1 kg is worked out and tested. With an input electric power of 59 W and operating at 144 Hz, it achieves a no-load temperature of 61.4 K and a cooling capacity of 1.0 W at 77 K. The changing tendencies of tested results are in good agreement with the simulations. The above studies will help to thoroughly understand the underlying mechanism of the inertance MCSPTC operating at very high frequencies.     

将CO2、R170和R41应用于跨临界空气源热泵热水器系统的性能对比研究

基于一套空气源热泵热水器系统,首先建立了相关的热力学参数计算模型,之后将CO₂、R170和 R41这3种制冷剂分别应用于该系统,并对跨临界循环的热力学性能及效率进行计算,最后对各性能参数进行详细对比。研究结果表明：在同样的工况下对比COP_heat和效率,R41系统分别比CO₂系统提升了31.77%和23.34%,而R170系统则提升了4.9%和3.6%;R41和R170在提升系统制热量方面也具有明显的优势;R41和R170的系统最优运行高压也比CO₂系统分别降低了35%和43%。因此,除了CO₂外,R41和R170也是另外2种很有潜力的应用于跨临界循环的制冷剂。     

运动员体能测试评定系统的设计

本文阐述了一个能在线测试和评定人体体能的系统。该系统能根据奥氏线列图计算人体的最大摄氧量(VO2max)和计算PWC170机能。该系统的实现对运动生理的研究和科学地选择和训练运动员都有现实意义。     

百万机座环板制造工艺研究

介绍了1 000MW汽轮发电机机座内环板下料用气割代替加工,使环板槽口气割后在一条直线上,保证组焊后11M高的发电机机座同心度在3mm以内.其优点是极大的降低了制造成本,提高了生产效率,外观质量及尺寸均满足设计图纸要求.     

基于调制电磁脉冲场的主动电磁探测研究

在车辆检测中,主动电磁探测因其性能受环境干扰影响小而越来越受重视。但是主动电磁探测常采用连续波工作,车辆的反射信号与直耦信号叠加在一起,使得检测算法非常复杂。为了大幅度简化检测算法,提出了一种调制电磁脉冲场方法。本系统包括一个磁偶极子发射天线和一个接收线圈,发射天线持续地辐射经正弦信号调制的且极性周期性改变的脉冲信号,这样就产生了一个具有低频成分的发射电磁场。如果目标存在,在接收电磁场的脉冲间隔内,就会出现目标的涡流二次场。连续地在接收电磁场的脉冲间隔内采样并做谱,如果出现此低频成分,则表示目标存在。     

G170柴油机的开发

G170型柴油机是南宁机械厂自行开发的G16 5型柴油机的换代产品 ,它具有良好的经济性、可靠性、耐久性及较大的功率储备。笔者不仅就产品水准与国内外同类机型作对比 ,而且还逐一阐述其性能参数、开发原则、部件结构及试验结果等诸多技术问题     

基于以太网的PLC与PC机通信

该文介绍了如何实现富士MICREX-F F70S PLC通过富士MICREX-F FFU170B以太网模块与PC机的以太网通信。FujiFFU170B以太网支持四种通信模式,本项目中使用了命令设置模式来实现PC与PLC之间的以太网通信,实现了PC机对PLC的远程控制。     

Individual differences in valence modulation of face-selective m170 response.

Magnetoencephalography was used to examine the effect of individual differences on the temporal dynamics of emotional face processing by grouping subjects based on their ability to detect masked valence-laden stimuli. Receiver operating characteristic curves and a nonparametric sensitivity measure were used to categorize subjects into those that could and could not reliably detect briefly presented fearful faces that were backward-masked by neutral faces. Results showed that, in a cluster of face-responsive sensors, the strength of the M170 response was modulated by valence only when subjects could reliably detect the masked fearful faces. Source localization of the M170 peak using synthetic aperture magnetometry identified sources in face processing areas such as right middle occipital gyrus and left fusiform gyrus that showed the valence effect for those target durations at which subjects were sensitive to the fearful stimulus. Subjects who were better able to detect fearful faces also showed higher trait anxiety levels. These results suggest that individual differences between subjects, such as trait anxiety levels and sensitivity to fearful stimuli, may be an important factor to consider when studying emotion processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

RE170、RE170/R227ea与矿物油的互溶性评价

随着制冷剂R22逐步淘汰, RE170、RE170/R227ea新型环保制冷剂有应用前景, 其和润滑油能否互溶直接影响制冷系统的使用效果。根据标准SH/T 0699-2000建立了一套制冷剂和润滑油的互溶性测试系统, 对RE170、RE170/R227ea和矿物油的互溶性进行了试验研究。结果表明:RE170的矿物油溶液在含油率为10%~60%时, 当温度低至-50℃时没有出现分层或絮状物, 二者互溶性非常好;混合制冷剂RE170/R227ea的矿物油溶液在含油率为14.6%±0.5%的基准情况下, 当R227ea的质量分数在35%~60%变动时RE170/R227ea和矿物油的低温两相分离温度随R227ea含量增加而上升, 当R227ea质量分数低于38%时混合制冷剂和矿物油在-50℃时仍能良好互溶, 当R227ea质量分数超过55%时混合制冷剂和矿物油在室温下已经不能互溶。最后, 结合经验公式法和溶解度参数法提出了新的评价方法来评价纯制冷剂及二元混合制冷剂和矿物油的互溶性。