基于单片机与PC机通信的数据采集控制系统设计

设计出基于单片机与PC机通信的数据采集控制系统方法。被控对象经传感器、电压变换电路、A/D转换芯片与单片机相连,可将现场参数信息传送至单片机;单片机经继电器驱动控制被控对象运行。单片机与PC机经电平转换芯片相连,实现远程通信功能。该系统可以实时采集被控对象多种参数信息并送PC机处理,可以选择由PC机远程或单片机本地控制被控对象。     

基于PWM的三基色LED智能语音控制调光调色系统设计

本文根据节能、商用照明对灯光要求多样化的要求,充分利用LED的节能和可控性,选用红绿蓝三基色LED作为照明光源,针对当下流行的语音控制和PWM斩波控制,选用凌阳单片机SPCE061A,设计相应的LED PWM恒流驱动电路,组成智能语音控制商用照明系统。     

基于51单片机的电镀废水处理控制系统设计

设计了电镀废水处理控制系统,本系统采用MCS-51系列单片机为控制核心,完成电镀废水处理控制系统的设计。详细介绍了利用A/D转换芯片TLC2543进行模数转换,三八译码器74HC138与89S51的接口电路设计,对硬件原理图和程序框图作了简洁的描述。     

循环冷却水处理在线监控评价设备的开发

开发了一种新型循环冷却水处理在线监控评价设备,用于水处理对策在线评价、优化与核心水质参数在线监控。该装置以电厂凝汽器循环冷却水的实际流态、水质、金属材质、换热强度为基础,对换热器污垢热阻、腐蚀速率及核心水质参数(pH、ORP、浓缩倍率)进行在线实时监测,以此为依据,对水处理剂加药浓度在线评价,并实时调整。设计了监控系统硬件,包括:污垢热阻检测器、腐蚀速率检测器、自动加药装置、水质参数分析仪表和工控机等,利用Delphi7.0编制了系统软件,可完成监控参数设置、实时显示、在线控制、历史数据查询、报表打印等。该装置应用于山东兖矿集团兴隆庄电厂1号机组,实验结果表明:该装置可实时评价水处理加药方案,有效地抑制污垢热阻生长,减轻换热器腐蚀,瞬时污垢热阻 <1.5×10^-4 m²·K·W^-1,腐蚀速率<0.005 mm·a^-1,循环冷却水浓缩倍率由2倍提高到4倍,优化了水处理方案,提高了电厂经济效益。     

基于单片机的PID温控系统在塑料挤出机中的应用

针对在塑料挤出过程中温度控制的重要性，介绍了一种新型的PID温度控制系统。该系统采用高性能单片机芯片，可以方便地对系统加热、冷却周期及PID的各个参数进行在线设定和修改，提高了塑料挤出机的温控精度。     

基于并联电阻网络的轮胎磨耗检测系统设计

针对轮胎磨耗量检测设备结构复杂、成本高、操作繁琐等问题,开发出基于并联电阻网络、无线收发模块和STC12C5A60S2单片机的实时检测轮胎磨耗量的轮胎磨耗检测系统。该系统利用并联的电阻网络将轮胎磨耗量转换成模拟电压值,并通过模数转换电路将模拟电压值变为便于单片机处理的数字量,最后通过无线收发芯片将数据采集到STC12C5A60S2单片机中进行处理和计算,并将结果显示在液晶显示屏上,从而实现对轮胎磨耗等级的判断和预警。通过轮胎磨耗模拟试验设计,得出轮胎磨耗量与总电阻的倒数呈线性关系,从而实现轮胎磨耗量的测量。     

滚镀过程中电流密度在线监控系统的设计

针对滚镀过程中电流密度随机多变的特点,设计出一套能够在线监控滚镀过程中电流密度的闭环系统。介绍了该系统的架构,并详细阐述了上位机、高频电源模块和电流密度采集设备的设计思路。设计的闭环系统借助磁敏感传感器采集并经换算获取滚镀过程中的实时电流密度,并将其反馈至控制芯片,通过控制高频电源模块的输出,实现对滚镀过程中电流密度的在线监控。     

屏蔽泵保护系统的研究与应用

针对长北天然气处理厂生产污水系统屏蔽泵P-4001A/B由于上游过滤器堵塞,造成屏蔽泵工作温度过高,常常损毁泵体情况,利用单片机W77EO58、16位A/D转换芯片、完成采集系统的硬件设计,通过单片机C语言进行采集系统的嵌入程序编写实现对屏蔽泵出口压力、流量、泵体温度的高精度采集。试验表明可以对P-4001A/B泵运行状态实时监控并连锁报警。     

运转中回转窑大直径在线测量仪

为确保回转窑安全正常运行,需要定期对回转窑中心线、支承托轮及轮带直径进行在线测量,根据测量结果调整回转窑的位置。本文介绍一种采用双滚轮结构的在线回转窑大直径测量仪,它主要由摩擦滚轮、滚轮轴、编码器、支撑及弹簧预压力机构和单片机控制系统等组成。该仪器的双滚轮结构和滚轮外圆直径表面防滑纹特殊处理以及跟随装置能够保证滚轮与被测回转体表面平行,能够有效避免和减小滚轮打滑引起的测径误差。该仪器能够实时自动修正滚轮直径热膨胀误差,它对轮带及托轮的动态直径测量总误差小于0.5mm,具有推广应用价值。     

基于单片机AT89S51的温湿度控制仪

在对国内外同类产品分析研究的基础上,作者设计了一种基于单片机控制的温湿度控制仪,从硬件和软件两方面设计并实现了对温湿度的精确控制,该控制系统主要采用AT89S51、LED显示器、SHT11等芯片,并对其组成以及硬件电路进行了详细的介绍,阐述了温湿度控制系统的工作原理以及设计方法。最后通过系统软硬件联机调试,实现了温湿度信号检测与控制,达到了预期要求。     

用好监测换热器

随着水资源日益紧缺,为了节约用水,实际中更多地采用循环用水的方法,随着循环水浓缩倍缩的提高,对水质监测的要求也越来越高.目前的水质监测设备主要以监测换热器为主,用好监测换热器,加强对水质的监测,显得越来越重要.     

粘胶纤维厂制冷系统压缩热的利用

根据粘胶纤维生产的特点,利用制冷压缩机产生的压缩热优化设计粘胶纤维厂制冷系统。该制冷系统是先将制冷压缩热作为包装箱烘干线的热源进行第一次利用,其加热的软水进行第二次利用。该制冷系统取消了常规设计中的冷却系统设备。结果表明:粘胶纤维厂制冷系统采用这种优化方法,制冷系统压缩热有效利用率达53%,节电12.5%,相当于制冷系统能耗减少60%以上。     

Waste to water: a low energy water distillation method

This paper describes a new water distillation method and apparatus. It is a low-cost system operating at low temperature and sub-atmospheric pressure that can produce water at different scales, for large cities or remote rural communities, thus suitable for the First World or the Third. The system may be configured to use waste heat from power plants, allowing co-generation of fresh water and with electricity. Though using waste heat allows for water production efficiency which is better than the current leading technologies, the process can also be made to run with other sources of low quality heat and alternative energy sources.     

基于B/S结构的空气源热泵热水机组的远程监控系统设计

设计基于B/S结构的空气源热泵热水机组的远程实时监控系统,介绍系统的体系结构、实现技术和软件功能.实际运行结果表明,该系统具有良好的稳定性、灵活性、扩展性和可维护性.     

On-line monitoring and quantitative analysis of biofouling in low-velocity cooling water system

To monitor and analyze the biofouling phenomenon caused primarily by microbial suspended solids (MSS), a ‘biofouling tube’ apparatus consisting of a carbon steel tube, a differential pressure transmitter, a corrator, and a cooling water circulation device was designed and fabricated. By measuring continuously the pressure drop across the biofouling tube and using the correlation between the fluid’s friction factor and surface roughness, we quantitatively analyzed the influence of MSS concentration, temperature, and fluid velocity on the rate of biofilm growth on the metal surface. The result indicated that the fluid velocity had the most profound impact, e.g., lowering the linear velocity from 0.3 to 0.15 m/sec resulted in about a four times higher biofouling rate. Up to 50 ppm MSS, the biofouling rate was proportional to the MSS concentration. The biofouling rate at 35°C was about 1.75 times higher than that of 45°C., probably due to the diminishing effect of thermolabile microorganisms exposed at 45°C. It was also demonstrated that the biofouling could be significantly reduced by incorporating cooling water treatment programs such as protective pre-filming and adding corrosion inhibitors. This apparatus, if installed on-site at a sidestream of a cooling water system, could be used to monitor the biofouling tendency on-line and to suggest timely preventive maintenance actions.     

水夹点技术在循环冷却水设计中的应用

运用水夹点技术,对循环冷却水系统进行优化.传统的循环冷却水系统采用平行换热网络设计.换热效率低,用水量大.采用连续换热网络,对传统循环冷却水系统进行优化设计后的用水网络.可取得较高的冷却塔进口水温和较小的用水量,从而达到节约用水、提高换热效率的目的.     

热处理对微乳液法制备纳米氧化镍的影响

微乳液法是近年来制备纳米颗粒的有效方法之一，具有装置简单，操作容易，微粒可控等优点。以氯化镍和氨水为原料，以Triton X-100／环己彬正己醇／水为反相微乳体系，成功制备出纳米氧化镍前驱体，然后对前驱体进行热处理，得到纳米氧化镍粉末，系统考察了热处理对纳米氧化镍颗粒形貌、粒径分布的影响。结果显示，利用微乳液法制备的氧化镍纳米颗粒大小、形态及分散性优于经热处理后的粉末；X射线衍射谱及透射电镜显示，热处理后的氧化镍粉末粒径随着热处理温度的升高而增大。     

A new two-dimensional experimental apparatus for electrochemical remediation processes☆

Electrochemical extraction of contaminants from soils is a promising soil decontamination technology. Various experiments have been conducted to study electrochemical reactions and geochemical processes in the electro-chemical extraction using different experimental apparatuses. This paper presents the development of a new closed two-dimensional (2D) apparatus that can better simulate the field application of the technology and ac-curately monitor the most important electrochemical parameters to understand the process. The innovative fea-tures of the new apparatus include the outer and inner electrodes designed to apply a non-uniform electrical field across the specimen as in the field electrochemical remediation process, the probes installed to measure the 2D distribution of electrical voltage, and the gas and fluid volume measurement devices used to accurately monitor the gas generation and electroosmotic flow rates at both electrodes as a function of time. The components of this new apparatus and the features of each component are described. The operating procedure and some typical re-sults from three experiments with the apparatus are demonstrated. The results show that the variation of the gas generation rate is in good agreement with the electric current. Their relation provides a valid evaluation for elec-trochemical behavior of the system and Faraday's laws of electrolysis. The 2D profiles of cadmium concentration and voltage distribution at the end of the experiment reveal the great effects of a non-uniform electrical field on the contaminant mobilization.     

Design of a laboratory experiment on heat transfer in an agitated vessel

A novel teaching laboratory experiment is described, which demonstrates heat transfer under agitation. The experiment involves a simple and inexpensive apparatus with necessary basic components. The laboratory deals with the experimental determination of the heat transfer rates and the overall heat transfer coefficient between steam and water in an agitated vessel. The apparatus can be operated under both static and flow conditions, which affords the student an improved understanding of heat transfer during transient and steady-state modes. Further, student is trained to study the effect of the impeller speed and water flow rate on the rate of heat transfer. By performing the experiment, the student is able to determine the overall heat transfer coefficients experimentally, and compare the results with those obtained from theoretical calculations using correlations available in the literature. In addition, while working in groups, students develop team work and technical writing skills in preparing a comprehensive laboratory report.     

LiCl溶液垂直管外降膜发生效果的实验

为了探究LiCl水溶液在低位太阳能吸收式制冷系统中的发生过程中的传热传质效果,在降膜发生实验装置基础上研究了LiCl水溶液在垂直管外降膜发生的传热传质过程。阐述了不同运行工况如不同的热水和溶液的流量、热源的温度、溶液的浓度和系统压力对LiCl水溶液发生过程传热传质效果的影响。同时也进行了相同工况下LiBr水溶液的对比实验。结果表明相同运行工况下LiCl水溶液降膜发生过程和LiBr水溶液的降膜发生过程有着相似的变化规律。虽然LiCl水溶液的垂直降膜发生速率略低于LiBr水溶液,但传质效果相差不大,LiCl溶液的低运行浓度有利于循环热力性能的提升。