凝析油自动计量测控系统的设计

从减小生产工况对凝析油计量的影响、提高计量精度出发,提出了一种集凝析油产量和含水率计量为一体的高精度计量方案,介绍了该自动计量系统测控电路及其软件的设计思路,现场运行与测试表明该自动计量系统原理正确、工作稳定、精度较高。     

Viscosity of Alternative Refrigerants R407C and R407E in the Vapor Phase from 298.15 to 423.15 K

This paper presents new measurements of the viscosity of gaseous R407C (23 mass% HFC-32, 25 mass% HFC-125, 52 mass% HFC-143a) and R407E (25 mass% HFC-32, 15 mass% HFC-125, 60 mass% HFC-143a). The measurements were carried out with an oscillating-disk viscometer of the Maxwell type at temperatures from 298.15 to 423.15 K. The densities of these two fluid mixtures were calculated with the equation-of-state model in REFPROP. The viscosity at normal pressures was analyzed with the extended law of corresponding states developed by Kestin et al., and the scaling parameters needed in the analysis were obtained from our previous studies for the viscosity of the binary mixtures consisting of HFC-32, HFC-125, and HFC-134a. The modified Enskog theory developed by Vesovic and Wakeham (V-W method) was applied to predict the viscosity for the ternary gaseous HFC mixtures under pressure. As for the calculation of pseudo-radial distribution functions in mixtures, a method based on the equation of state for hard-sphere fluid mixtures proposed by Carnahan-Starling was applied. It was found that the V-W method can predict the viscosity of R407C and R407E without any additional parameters for the ternary mixture.     

基于国产龙芯GS32I的小系统的硬件设计

针对目前在嵌入式领域使用国产芯片比较少的现状,简要介绍了国产32位处理器龙芯2号GS32I的工作原理,着重从硬件方面介绍了其接口的扩展方法和扩展信号的定义,同时给出了基于GS32I小系统的硬件设计方案。     

时钟芯片在电压监测仪校验装置中的应用

根据电压监测仪校验装置需要建立一个标准时钟,对电压监测统计仪进行时间精度校正的要求,介绍了I2C总线接口时钟芯片PCF8583的基本原理,提出了利用DS32KHz给PCF8583提供高稳定度频率信号,从而实现了标准时钟的方案,并给出了PCF8583与MCS51单片机接口设计。     

平台水处理DCS系统报警限值在线管理实现

海上石油生产环境的恶劣性决定了海洋平台水处理DCS系统工控参数报警限值的重要性,而海上注采生产工艺的改进以及设备的更新均会导致平台水处理工艺被检测工控参数报警限值的变动。本文运用组态软件RSView32的内嵌式开发语言VBA,结合网络技术与数据库管理技术,研究并实现了平台水处理DCS系统对工控参数报警限值的在线管理。系统的长期运行证明了该种方法的可行性和实用性。     

组态软件RSVIEW32与VB、EXCEL结合的复杂生产报表解决方案

本文阐述了如何将工业控制软件RSYIEW32与编程浯言VB的易用性、办公软件EXCEL强大的数据处理能力结合起来，解决工业控制软件对复杂报表支持的不足，实现监控数据的记录、分析并形成生产报表，从而满足生产需求。     

RSView32组态软件在火电厂生产调度监控系统中的应用

主要论述了RSView32组态软件，在火电厂生产调度监控系统中的应用，并介绍了使用高新技术网络采集控制器NETRTU。其配置简捷、高速和可靠，将代表着自动化硬件新的发展趋势，与RSView32组态软件配合使用真可谓绵上添花。     

MC68HC908GP32单片机编程器的设计与实现

在分析Motorola M68HC08系列MCU的Flash存储器编程模式基础上，提出了MC68HC908HP32芯片的一种简明而实用的编程器设计方案，给出了基本设计思想，硬件设计电路，软件设计框架，并与Motorola公司提供的电路进行了对比分析。     

Viscosity of Gaseous Mixtures of HFC-134a (1,1,1,2-Tetrafluoroethane)+HFC-32 (Difluoromethane)

This paper reports experimental results for the viscosity of gaseous mixtures of HFC-134a (1,1,1,2-tetrafluoroethane)+HFC-32 (difluoromethane). The measurements were carried out with an oscillating-disk viscometer of the Maxwell type at temperatures from 298.15 to 423.15 K. The viscosity was measured for three mixtures containing 25.00, 52.40, and 74.98 mole% HFC-134a in HFC-32. Experimental results for the viscosity at normal pressures show a minimum as plotted against mole fraction in the higher temperature region, which may be the first experimental observation of the minima for dilute binary gaseous mixtures of HFCs. The viscosity at normal pressures was analyzed with the extended law of corresponding states developed by Kestin et al., and the scaling parameters were obtained for unlike-pair interactions between HFC-32 and HFC-134a. The modified Enskog theory developed by Vesovic and Wakeham was applied to predict the viscosity for the binary gaseous mixtures under pressure. As for the calculation of pseudo-radial distribution functions in mixtures, a method based on the equation of state for hard-sphere fluid mixtures proposed by Carnahan–Starling was applied.     

基于STM32的智能水肥一体化控制系统的设计

为达到灌溉系统中水资源与肥液的最高利用率,设计了一种水肥一体化自动控制控系统,可实现灌溉与施肥的一体化自动控制。基于STM32微控制器,设计了核心控制器,集灌溉算法和施肥算法于一体;同时设计了DO、AI接口,实现对外设的控制与肥液参数的采集;增加SD存储卡,实现对灌区历史数据、概貌历史数据的存储;增加迪文工业串口屏人机交互部分,实现系统数据的显示、设置参数的输入。实验结果表明,基于定时策略与周时钟策略的灌溉控制算法实现了对灌区精确、稳定的灌溉控制,基于增量式PID的施肥控制算法实现了对肥液EC值的精确、快速控制。