基于PLC的变压吸附氮气发生控制系统设计

变压吸附制氰是采用碳分子筛为吸附剂，利用变压吸附原理来获取氮气，在一定的压力下，利用空气的氧、氮在碳分子筛孔隙中扩散速率不同而达到分离空气的目的。本文对变压吸附氮气发生器的自动控制系统进行设计．通过可编程控制器(PLC)来控制多个阀门以实现工业生产上对氯气的连续、大量需求。     

多孔介质变压吸附过程仿真计算

根据多孔介质变压吸附理论,对试验室小型变压吸附制氧系统吸附过程进行了数学仿真计算,结果表明:减小吸附床层的间隙率可以改善氧产品的纯度,压缩机的功耗会增加;随着原料进气流量的增加,进出口压降呈线性增加,产品纯度则按非线性减小;当吸附床层高径比增加时,吸附柱的压力降呈线性增加,但在较低值时的增加对产品纯度改善较好;为了更好地减小吸附柱的压力降,达成节能的效果,建议间隙率控制在0.35～0.4之间,高径比控制在9.5～12之间,操作时将空气进气流量调到6.2m3/h左右为宜.     

吸附床的传热传质强化及设计实例

分析了吸附制冷系统中吸附床的传热传质特性,介绍了目前吸附床传热传质研究状况及常用的强化措施,在此基础上给出了一具采用强化方法的新型吸附床设计方案。实测性能表明,对吸附床传热传质的强化是吸附制冷装置实现广泛应用的关键所在。     

13X型分子筛用于高压空气干燥时吸附极限露点的测定

介绍了13X型分子筛对高压空气进行变压吸附干燥试验，并对试验的模型。状态和结果进行了分析，得出了试验工况下该种分子筛所能达到的极限露点。     

碳分子筛分离空气制取富氮

在工业生产中,传统的制氮方法是深冷空气分离法。这种方法采用的深冷空分装置复杂,操作麻烦,投资费用大,而且耗用大量的有色金属。 另一种方法是用分子筛变压吸附分离空气制取氮气,这是世界上一种新的制氮技术。它是利用分子筛对气体分子的吸附和解吸的原理,将空气中的氮和氧分离而获得高纯度的氮气。这种方法又可分为两种,一种是沸石(MSZ—5A)分子筛法,另一种是碳(MSC)分子筛法,它们的主要区别住于对氮氧吸附的先后不同。两者比较,碳分子筛变压吸附分离空气制取氮气有如下优点: 1.能耗小。空气中含氮量约为含氧量的四倍,     

我国最新变压吸附制氢技术程控系统投入运行

日前，由中科院大连化物所控股的大连圣迈气体分离工程有限责任公司自行设计、制造、安装的1000Nm^3／h焦炉煤气变压吸附制氢装置在鞍钢集团新钢铁有限公司竣工并交付使用，这标志着大连化物所已处于国内变压吸附制氢工业领域的领先地位。     

拟连续吸附制冷循环的实验与模拟研究

对拟连续吸附制冷进行了实验及理论模拟研究,建立了拟吸附制冷系统动态二维传热传质耦合模型,实验数据和模拟相吻合,在引入温度波理论的基础上,分析了各参数对系统性能的影响,为连续吸附制系统的设计及性能优化了理论及实验依据。     

化学吸附制冷新进展

利用吸附剂对吸附质的强烈吸附能力，可以促使吸附质液体蒸发，从而实现吸附制冷循环。结合国内外化学吸附制冷研究的最新动态，分别就化学吸附的工质对的选择、吸附床的强化、新型分析理论和测试手段等方面进行了一些总结和归纳。     

浅谈PSA变压吸附制氢工艺及优化

化工行业每年为国家生产大量的化工产品，满足了人们的生产生活所需。在工业化稳步发展的今天，化工企业内的工艺变革成为关键性内容，许多化工企业中都涉及PSA变压吸附制氢工艺，由于这一工艺的复杂性，变压吸附效果深受多种因素影响，为发挥该工艺的优势，化工企业需紧跟行业发展，持续推进PSA变压吸附制氢工艺的创新，以保持工艺的先进性。基于此，本文从影响变压吸附的因素着手，详细介绍了PSA变压吸附制氢工艺的改进与优化，对化工企业中的工艺推广具有指导价值。     

空气循环蒸发分离电镀废水处理系统喷雾分离塔试验研究

喷雾分离塔作为空气循环蒸发分离电镀废水处理系统中最重要的热质传递部件,决定了整个系统的性能.搭建了喷雾分离塔性能测试试验台,研究了不同入口空气温度、空气流量、喷雾流量以及入口溶液浓度对喷雾分离塔传热传质性能的影响.研究表明:通过降低入口空气温度、空气流量和入口溶液浓度,提高喷雾流量,可以提高喷雾分离塔热效率;提高入口空...     

基于磁隙式吸附机构的槽车清洗机器人

给出了一种基于磁隙式吸附机构的槽车清洗机器人机构设计方案,采用磁隙式吸附装置平衡清洗作业过程中高压水枪反向冲击力产生的倾覆扭矩,提高系统稳定性裕度。建立数学模型描述清洗作业力学行为,利用有限元仿真优化磁吸附模块设计参数,计算不同气隙高度下单个磁吸附装置产生的吸附力。根据仿真结果,当采用2块40 mm×40 mm×15 mm与2块80 mm×40 mm×15 mm的永磁铁,磁铁间隙为10 mm,轭铁厚度为9 mm,气隙高度为10 mm时,单个磁吸附装置能够产生693 N的吸附力,槽车清洗机器人能够在20 MPa的清洗水压下稳定地工作。     

A study on the slip velocity on a pair of asymmetric electrodes for AC-electroosmosis in a microchannel

In numerical studies on microscale electroosmotic flows, the electric double layer (EDL) effect is usually predicted by solving the traditional Navier-Stokes equation subjected to the slip velocity induced by the electric-charged wall as a boundary condition. Recently, Suh and Kang (Physical Review E 77, 2008) presented the asymptotic solutions of the ion transport equations near a polarized electrode under the action of an AC field, and then proposed a new theoretical model of the slip velocity on the electrode considering the ion adsorption effect. In the present paper, we apply the model to a two-dimensional AC-electroosmotic flow in a microchannel to calculate the slip velocity on a pair of coplanar asymmetric electrodes embedded on the bottom wall, and then experimentally measure the slip velocity using the micro-PIV technique to validate the theoretical model. Comparison shows an excellent overall match between the theoretical and experimental results, except for on the narrow electrode at low frequencies. Next, we numerically perform parametric studies regarding the AC frequency, effective Stern-layer thickness and ion adsorption effect to further understand the characteristics of the AC electroosmotic flow. Results show that, as the frequency increases, the slip velocity also increases. In addition, the velocity decreases with increasing either Stern-layer thickness or ion adsorption effect. This paper was recommended for publication in revised form by Associate Editor Dongshin Shin Sangmo Kang received a B.S. and M.S. degrees from Seoul National University in 1985 and 1987, respectively, and then had worked for five years in Daewoo Heavy Industries as a field engineer. He also achieved a Ph.D. degree in the field of Mechanical Engineering from the University of Michigan in 1996. Dr. Kang is currently a Professor at the Division of Mechanical Engineering at Dong-A University in Busan, Korea. Dr. Kang’s research interests are in the area of micro- and nanofluidics and turbulent flow combined with the computational fluid dynamics.     

Reproduction of air velocity in the entrance region of the test pipe in a wind tunnel

The airflow development in the pipe, in the entrance region of the wind tunnel located in the Lithuanian Energy Institute, the laboratory of Heat Equipment Research and Testing is investigated to analyze the conditions for the reproduction of air velocity values. The analysis is performed to reveal undeveloped flow conditions where the calibration of the devices is usually made, the entrance region of the pipes, or free stream from the nozzles. In this study, different flow regimes have been investigated using different air velocity measurement methods. Experimental and numerical results clearly show the features of the developing flow. They both demonstrate the stable core of the velocity profile up to 5 D in the pipe and ≤1 D from the entrance into the free stream in the testing chamber. Ultrasonic anemometer (UA) installed in the aerodynamic test facility shows reliable and highly comparable results with another non-intrusive device – laser Doppler velocimeter (LDA) in a range of velocities from 0.05 m/s up to 30 m/s. UA integrated into the wind tunnel is not found to be used for metrological issues for air velocity. Due to the fast response, they both enabled to analyze fluctuations in the flow. Local vortices identified in the flow have influenced the low-frequency fluctuations and the scatter of measurement results. Moreover, high-frequency fluctuations found in the flow originated from the flow turbulence and might be due to the electronic or acoustic noise. The stabilization of the entrance region in the pipe influences the mean value of air velocity, the transversal distribution of velocity and the development of axial velocity in different test sections of the pipe in a wind tunnel. Along with the recirculation zones in cavities of ultrasonic transducers, these factors are essential that make an impact on the reproduction of air velocity value.     

微小器件吸附式微夹持器的研究

在基于精密电控台与视觉识别为一体的基础上,针对微小器件吸附式微夹持器的特点和微小零件在装配中需要满足的高质量和高效率要求,进行了微小器件吸附式夹持器的研究以及在装配过程中的受力分析,比较不同材料吸附式微夹持器的可应用度,并根据运动过程中加速度、减速度对零件在吸附头上引起的零件窜动量,对吸附力进行可行性分析及对CCD视野识别的影响分析。通过理论分析得出合理的结构,通过实验验证所设计的吸附式微夹持器可以满足装配要求。     

一种新型真空吸附装置的研究

提出一种具有振动分离功能的新型真空吸附装置,这种装置的优点是通过高频振动装置能够实现圆片（薄片）在高速起边和搬运过程中彻底分离。对装置的工作原理、结构进行了介绍,并对真空吸附装置的吸附力及高频振动装置的振动力进行了计算分析并列举了应用实例。     

基于反馈原理的高楼逃生器

依据现代设计心理学,利用四杆机构、楔形滑块及摩擦块组成的速度反馈机构自动控制速度,以及分步逐级减速的方法设计了操作简易快捷的高楼逃生装置,它具有逃生速度可实现自动调节并稳定在可控范围、在不需要其它能源下能照明和发出求救信号、对称结构可以像蠕虫一样交互式下降、可实现多人次循环逃生等特点。     

蒸发式冷凝器管外水膜与空气传热性能及机理的研究

建立了蒸发式冷凝器实验平台,测试了不同喷淋密度及迎面风速对管外水膜与空气传热与阻力性能的影响,结果表明管外水膜与空气传热受迎面风速的影响较大,而受喷淋密度影响较小。得到了管外水膜与空气传热系数计算式,最大相对标准偏差为12.2%,进而分析了蒸发式冷凝器中水膜与空气的传热机理。     

吹、吸气幕应用于排风柜的研究

针对现有排风柜技术的不足，引入吹、吸气幕技术，开发出一种新型吹吸、气幕式排风柜，并通过实验研究，数值模拟对照，得到了最佳设计参数。工程实例表明，这种新型排风柜具有节能，操作舒适，控制效果好的优点。     

智能控制技术在PSA制氢中的应用

主要介绍了智能控制技术在莱钢焦化厂焦炉煤气变压吸附（PSA）技术制氢装置PLC控制系统中的应用,并简要阐述了其技术路线和创新点。     

The behavior of the liquid-like Langmuir's adsorbed film on air bearing surfaces

The contamination of slider air bearing surfaces may lead to a critical failure of hard disk drive systems. The contamination may be classified into two types: the liquid-like contamination and the particle contamination. In this study, the liquid-like contamination is concerned. It is assumed that the liquid-like contamination is caused by the adsorption of contaminant molecules in air. A mathematic model has been developed to predict the accumulating process of the liquid-like contaminant on air bearing surfaces. Numerical analysis of the behavior of the liquid-like adsorbed film for two different types of air bearing surfaces was conducted by using the proposed model based on the Langmuir adsorption. The results show that the contaminant tends to accumulate on the recession area of the air bearing surface when the viscosity of the liquid-like adsorbed film is low. However it may also accumulate in the front area of the air bearing surface when the viscosity is as high as 20 Pa s.