厚层稠油油藏直平组合火驱机理研究与试验

针对厚层稠油油藏常规直井火驱火线超覆严重、纵向动用程度差、采出程度低等问题,采用数值模拟方法,明确直平组合火驱中火线波及规律,分析直井、水平井在不同阶段的生产特征,明确直井、水平井作用机理.研究结果表明:采用直平组合火驱的井网模式改变了原有直井的火驱流场,起到向下牵引火线作用,提高了纵向波及体积;采用直平组合式井网进行...     

Deducing the stage-discharge relationship of rectangular broad and sharp-crested contraction devices

Flumes with a local contraction of the channel width are a common way for accurately measuring the flow discharge. In this paper, the outflow process of rectangular broad and sharp-crested contraction devices is modeled using the dimensional analysis and the incomplete self-similarity condition. The proposed theoretical stage-discharge relationship is tested using measurements available in the literature. The proposed power equation is characterized by a value of the exponent close to 1.5 and a coefficient depending on the contraction ratio. The proposed flow-measuring flumes are characterized by a good accuracy of the measured discharge (ranging from −2.71 to 3.28% for the broad-crested contraction device and in the range from −0.24 to 0.31% for the sharp-crested one). Even if both flume types have good accuracy of the measured discharge (less than the limit of ±5% suggested in the literature), the developed analysis demonstrated that the sharp-crested device is characterized by the lowest values of the errors in the estimate of discharge, and this result increases the interest of this device in practical applications. The advantage of the proposed approach is combining an accurate estimate of the flow discharge and working regardless of the discharge coefficient estimate.     

Determining the flow correlation for an orifice with a non-dimensional number

Traditional devices like orifice meters play a crucial function as a flow measuring device because there is inaccuracy in the measurement of the flow measuring device concern. The pressure drop (Δp) between the upside and downsides of the orifice-pipe flow passage is calculated using Bernoulli's principle. Orifice meter produces errors and uncertainty in the downstream of the flow because of wake or backflow. The proposed study provides the procedure to calculate the Δp and flow characteristics for a circular orifice for a compressible fluid (Air) with CFD analysis. The numerical study was carried out by considering combined parameters such as area ratio (σ) and space ratio (s) as geometrical parameters and Reynolds number as flow parameters to minimize the errors of the numerical calculation. The input parameter σ varies from 0.2 to 0.6, and the s varies from 0.1 to 0.9. Whereas the Reynolds number (Re) varies from 10000 to 100000. A non-dimensional number is defined by the combined effect of σ and s to generated correlations with accuracy which is enhanced predicted results of the work. The correlation will make a significant contribution to the flow monitoring device design.     

芳烃装置吸附塔与旋转阀的布置及配管

芳烃装置中的吸附分离工艺多采用美国某专利商的工艺,它使用一种固体吸附剂和一种液相解吸剂以及一个叫做旋转阀的流体分配装置,通过模拟移动床的方法从混合进料中以高收率获得高纯度对二甲苯抽出液。该装置的管道设计是围绕吸附塔与旋转阀展开的,由于该工艺对于吸附塔和旋转阀之间相连的24根床层管道要求等容积配管,且对床层最大容积有所限制,因此管道设计难度可想而知。文中将从设备布置和管道布置两个方面进行分析,梳理设计思路,最终满足吸附分离装置的管道设计要求。     

《固定式压力容器安全技术监察规程》中压力容器类别的划分

TSG R0004—2009《固定式压力容器安全技术监察规程》中压力容器类别划分按设计压力、容积和介质危害性三个因素确定,不再考虑容器在生产过程中的作用、材料强度等级、结构形式等因素。根据危险程度的不同,仍然划分为Ⅰ类、Ⅱ类、Ⅲ类,在不同介质分组坐标图上查取相应的类别,简单易行、科学合理、准确唯一。并将介质分为两组,一组为危险性介质;另一组为非危险性介质。按介质组别分类图确定压力容器类别,将分类图分区域可以迅速确定压力容器类别根据强化危险性原则,突出本质安全思想,笔者认为对第二组介质的类别划分有些部分不太合理,根据目前的划分方法,某些压力容器的容积相差1 L或压力相差0.01 MPa,可压力容器类别却从Ⅲ类压力容器变成了Ⅰ类压力容器,建议将这范围内的类别划分从Ⅰ类压力容器改为Ⅱ类压力容器。     

沥青混合料车辙试验前后其体积参数变化规律分析

研究沥青混合料车辙试验前后其体积参数对提高沥青混合料高温稳定性具有重要意义。采用轮碾法成型沥青混合料试件,并对试件钻芯取样,分析芯样的空隙率、矿料间隙率和沥青饱和度等体积参数。结果表明:辙槽处芯样的空隙率明显小于车辙前的;油石比在4.0%附近时,轮迹两侧的空隙率大于等于车辙前的,随着油石比的增大,轮迹两侧的空隙率减小并小于车辙前的;辙槽处芯样的空隙率要小于轮迹两侧的。     

浅谈建筑电气工程审计的几种方法

针对建筑电气工程几种常用的审计方法进行了分析,分别介绍了图纸审计法、现场测量法、询问法、开挖法、相关数据审计法、重点抽查法的特点及工作重点,以指导审计人员灵活运用,提高审核效率。     

LiNbO3晶体中引入π位相差实现选择性擦除

在晶体中进行大容量多重体存储 ,需要对晶体中记录数据进行修改 ,这就使得选择性擦除必不可少。介绍了铌酸锂晶体中实现选择性擦除的原理 ,着重介绍了在物光和参考光中引入π位相差的几种方法 ,通过引入π位相差来记录互补全息图 ,利用全息图及其他的互补全息图的非相干叠加来消除原全息图对晶体折射率的调制 ,从而实现对未定影全息图的选择性擦除。实现了在晶体中某一数据页面内部分数据的擦除 ,并从理论上对实验结果进行了分析。并给出了在某一数据页面内进行部分擦除的实验结果     

溪洛渡大坝混凝土特性及防裂措施

溪洛渡拱坝混凝土采用玄武岩粗骨料、灰岩细骨料,针对骨料特性,通过优化配合比、提高水泥要求以及外掺MgO等工程措施,有效地改善了混凝土的极限拉伸变形和自身体积变形,提高了混凝土的抗裂特性,保证了溪洛渡大坝混凝土的质量。     

未知样品中氯离子检测方法的探索

准确检测氯离子含量,尤其未知样品中氯离子含量的检测准确度对水泥企业很重要。本文通过减小称样质量、稀释溶液体积、过滤溶液、提高标准溶液浓度四种方法措施,提高电位滴定仪对未知样品中氯离子含量的检测准确度。