Performance of Rotating Spray Plate Sprinklers in Indoor Experiments

The use of rotating spray plate sprinklers (RSPS) can reduce the water and energy requirements in pressurized irrigation systems. Installation of RSPS in continuous move irrigation machines, such as traveling trailers (nozzle booms), presents relevant advantages compared to sprinkler-gun machines. The aim of this study is to develop design criteria for continuous-move irrigation machines using the RSPS Nelson Rotator R 3000 D-4. Water distribution by this RSPS was evaluated in an indoor facility under the following experimental conditions: 6.1, 7.0, and 7.8 mm nozzle diameters; 1.0 and 1.5 m nozzle height above the ground; and working pressures of 100, 150, and 200 kPa. The water distribution patterns were overlapped at 3 and 4 m distances, the simulated Christiansen uniformity coefficient averaged 91.8%, and the simulated average precipitation rate under the different experimental conditions ranged between 23 and 57?mm?h?1. These values are acceptable for a wide range of irrigation-machine applications.     

Interaction between Rotating Elliptic Cylinder and Fixed Circular Cylinder

The general planar motion of an elliptic cylinder through an inviscid and incompressible fluid in the vicinity of a fixed circular cylinder is investigated analytically. The velocity potential is derived by using the successive-image method and the perturbation method, and it is used to determine the hydrodynamic interactions between them. In a relative coordinate system moving with the uniform flow, the kinetic energy of the fluid is expressed as a function of 15 generalized added masses due to the motion of these two cylinders. The generalized added masses are then employed to determine the translational and rotational motion of the elliptic cylinder based on the dynamic equations of motion that are obtained from Lagrange's equations of motion. Numerical results show that the initial configuration of the elliptic cylinder greatly affects its subsequent motions.     

旋转喷雾半干法烟气脱硫技术的开发和应用

济钢国际在对比国内外脱硫技术、分析烧结机烟气特点,以"以废治污、副产物资源化利用"为基本点,引进、消化、再创新,开发了旋转喷雾半干法脱硫技术,主要包括脱硫除尘系统,脱硫剂(石灰粉)贮存及浆液制备供给系统,脱硫灰输送、循环及外排系统和排空系统等。该技术在济钢400m2烧结机应用投产后,实现了与烧结机生产100%的同步作业率,外排烟气SO2浓度低于200mg/m3,吨烧结矿治污费用约6.9元/t。     

雾化冲击射流冷却热轧钢板的研究

利用有限元耦合场数值模拟计算方法对热轧钢板雾化冲击射流冷却进行模拟计算,结果表明,在其它条件相同的情况下,单喷嘴喷射时,在上喷和下喷的喷嘴附近冷却能力相同;多喷嘴喷射时,横向存在二次冷却,钢板表面横向温度分布总体上呈现逐渐降低的趋势。     

Green's Functions of Thin Plate Bending Problem under Fixed Boundary

The Green's functions of a point dislocation, a concentrated moment, a normal point force, a couple moment, and a couple bending force applied to an infinite plate with an arbitrarily shaped hole under a displacement boundary condition are derived in this paper. The closed-form stress functions are obtained by using the technique of the rational mapping function and the complex stress function approach. In the derivation, the analytical continuation and Cauchy integral are used for the different actions. Without loss of generality, some calculated results are shown for a square hole under a fixed boundary. The solutions show that the stress functions have different orders of singularity for the different actions. In order to illustrate the stress level due to bending moment and shear force clearly and efficiently, the effective stress of thin plate bending is shown.     

中厚板喷淋冷却换热模型的研究

为了研究水量与冷却能力的关系,对10~20 mm厚度的Q345钢板进行不同工况的喷淋试验,并对采集的温度数据进行整理分析。结果表明冷却能力在水流密度为2.5~2.7 m3/(min·m2)时达到峰值,同时获得了水流密度与换热系数的数学模型。通过对比分析,验证该模型可靠,可以作为工艺设计和生产的参考。     

WPD400中厚板喷印设备在邯钢新中板厂的应用

WPD400中厚板喷印成套设备不仅功能齐全,而且喷打印效果完全能与进口同类产品相媲美。本文介绍了该设备的组成、工作原理及使用效果。     

白云铁矿东采场固定公路喷淋系统建造

白云铁矿采场公路是由碎石级配路料修筑,在运矿车和洒水车作业过程中产生大量的扬尘和废气,不仅对人身和环境造成极大的损害,同时洒水车重载下坡也存在安全隐患。文章通过对铁矿固定公路运行情况进行研究分析,建造一套电控采场喷淋系统,完成采场固定公路洒水抑尘工作,实现矿山采场公路安全生产和环保。     

冷轧厂连退线助卷器翻板液压缸固定方式改造

针对邯钢西区冷轧厂连退线助卷器液压缸经常损坏的问题,分析了其损坏原因,并提出了相应的改进措施。实施改进后,液压缸动作平稳,再没有出现过液压缸损坏的问题,达到了预期的改造效果,保证了邯钢西区冷轧厂连退线生产的顺利运行。     

板式过滤机助滤剂喷涂量的影响因素及量化分析

简单介绍了板式过滤机助滤剂的喷涂原理,详细说明了助滤剂喷涂量的影响因素,结合设计实例给出了助滤剂喷涂量的计算过程,阐述了各种影响因素对助滤剂喷涂量的影响大小,指出了设计和调试过程中应考虑的问题。     

容积计量多喷板智能喷脂润滑系统的研制

文章对容积计量多喷板智能喷脂润滑系统的原理、容积式流量传感器工作原理、多喷板的控制过程、喷脂润滑系统的控制过程等进行了论述,指出该系统操作简单,可靠性高,易于维护,并且实现了一机多控、流量检测和给油量控制。     

奥氏体不锈钢中厚板连续喷淋酸洗工艺浅析

论述了奥氏体不锈钢中厚板连续喷淋酸洗工艺的技术特征,并对典型的卧式、立式连续喷淋酸洗机组设备组成和生产工艺加以分析和对比。介绍了连续喷淋酸洗技术在国内不锈钢中厚板生产厂的实际应用情况。     

Six of One, Half a Dozen of the Other: Problems With Working Fixed and Rotating Shifts.

This study examined the relationship between shift patterns and role stressors and strains, as well as the extent to which situational variables and individual variables mediate the relationship between shift patterns and strains. Using survey data from 397 Israeli nurses, the author found that nurses working fixed day (vs. rotating) shifts reported less strains, but more stressors. Individual and situational variables mediated the relationship between shift pattern and both affective commitment and intention to leave, respectively. Younger age and higher role ambiguity might account for fully rotating shift nurses' reports of intention to leave, and being an older, full-time employee with little role conflict and ambiguity might explain why fixed day (vs. rotating) shift nurses report greater affective commitment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

中厚钢板热处理方法比较

传统的中厚钢板热处理方法正逐渐被微合金化钢种设计、控制轧制、控制冷却、直接淬火工艺所代替。控制轧制细化晶粒,提高钢板强度和韧性,控制冷却可生产高强度超细晶铁素体和低碳贝氏体钢,在线直接淬火可代替原传统离现淬火热处理,减少消耗,降低成本,提高钢板外形质量。不同钢种的中厚板热处理工艺参数应根据生产厂装备及钢种成分确定。     

Q460C钢板生产工艺的比较

对八钢和南阳汉冶特钢中厚板生产线生产的Q460C钢板进行对比分析,对八钢Q460C钢板的生产工艺改进提出了建议。     

Theoretical and Experimental Study on Water Offset Flow in Fluidic Component of Fluidic Sprinklers

Compared with other rotating sprinklers, the fluidic sprinkler controlled by an outlet clearance has a simpler structure and better hydraulic performance. The offset effect, happening in the fluidic component of the sprinkler, drives the sprinkler and controls its rotational direction. Theoretical and experimental research are conducted to study the water offset jets with a small ratio of 0.675 for the 10PXH sprinkler and 0.355 for the 30PXH sprinkler in the fluidic components. Analytic solutions and other calculations deduce the reattachment lengths of the offset jets. Computational fluid dynamics (CFD) software simulates the offset flows in simplified models and real models of the fluidic components, in two dimensions and three dimensions, respectively, utilizing the volume of fluid (VOF) method to trace the shape of the interface between water and gas. Simulation results of the sidewall pressure distribution also obtain the reattachment lengths. The resulting experimental measurements of the static pressure and reattachment length are in line with the predicted results of the calculations and the simulations. These results indicate that CFD simulation can approximate the offset flow in fluidic components. On the basis of this study, some of the component sizes are confirmed.     

厚板及高强钢板的板型控制

本文介绍了厚板及高强钢板常见的板型缺陷,分析了其形成原因,提出了相应的控制措施。     

常规中厚板轧机与炉卷轧机的对比浅析

本文叙述了炉卷中厚饭轧机技术的发展．介绍了常规中厚板轧机和炉卷轧机各自的优缺点,并对这两种轧机的工艺特点进行了比较分析。     

Q345D中厚板两种生产工艺比较

文章介绍了CR和TMCP两种工艺的对比试验,研究了不同的生产工艺对组织和性能的影响。ACC设备投用后,运用TMCP工艺合理控制轧制方式及轧后冷却速度,钢板的性能优于CR钢板,抗拉强度和屈服强度明显提高。利用TMCP工艺降低Q345D中的Mn含量,减弱了钢板的中心偏析程度,提高了低温冲击韧性。同时TMCP工艺的应用,缩短钢板的轧制周期,提高了轧制节奏。     

单线循环固定抱索器客运索道线路阻力计算方法的比较及分析

根据单线循环固定抱索器客运索道的运行原理、运行工况及线路计算特点,对现用的两种索道线路运行阻力计算方法进行分析,在MATLAB软件平台上分别编写了该类型索道两种线路计算程序,对工程实例进行计算后对计算结果进行了对比、分析,最后指出了两种不同线路运行阻力计算方法的优缺点和适用范围。