混凝土搅拌机外文翻译

1、毕业设计外文文献翻译毕 业 设 计 题 目双旋卧式混凝土搅拌机设计翻译题目Mixing and mixing technology of understanding专 业机械设计制造及其自动化姓 名毕鹏飞班 级机A0731学 号10713030118指导教师余香梅机械与材料工程学院二O一O年十一月译文搅拌与混合技术的理解 可以或许测量不透明介质的流场。EPT义务情理与医学测试仪器中的CT相差不多。被测搅拌釜或管道外壁等距离贴附一组816只传感器一周， 电子过程断层成像技能电子过程断层成像技术EPT一种多相流体系的非接触式的实时检测和可视化技术。此传感器为长方形不锈钢电极片，既是发射器又是接收器

2、。釜或管道内要有两种具有不合电性能（电导率、电容率等）物料（不合电导率的液体、气体和固体、液体和固体）而后在有规律的电脉冲传染感动下，所有能够的相邻传感器组合的电压通过数据采集单元传送回计算机。打算机将记录所有电极的信号和先后次序，并采用图像重建技能回复复兴出釜或管道横截面的图像，每秒可获得高达100帧图像。如果采用多组传感器对不合高度履行断层成像，则可在图像重建技巧的辅助下，建立釜或管道的三维图像和实体造型。EPT系统无辐射危险、价格廉价、易于制作，响应速度比CT快且可以或许满足工业实时过程请求。但图像分析度比CT要低。因为EPT可以或许准确地测量出搅拌反应器中的流动地区、速度场、气体和固体

3、组分浓度分布，而这些数据可用于从空间和时间两方面验证多相体系的混淆模型和CFD模子，因此EPT技能可直接用于优化搅拌器的假想和操作，随着电子技巧、图像重建算法和打算机硬件的成长，EPT还 将被用于过程的线监测和控制。 混凝土搅拌机的性能取决于它们的组件的磨损。因此，他们的生活和性能可能会提高的基础上，理论和实践的结构耐磨性。这需要动态研究的磨损。在公路建筑，材料的耐磨损性升高一般选择。产生的改善不是很大。经济上的考虑要求其他的方法。混凝土搅拌机的操作是受影响最严重由冲击磨料磨损的叶片和腔室衬里，尤其是在高的压力，温度，速度，或生产力。对于现有的混凝土搅拌机，维修费磨损组件在很大程度上决定了整体

4、经营成本。结构队友的生产经验，里亚尔显示，磨损相关的维修停机时间达45-48的总停机时间。这样的概率LEMS占38-41的劳动力成本维修每年，而支出的维修及更换破旧和叶片和内衬组成部分对应混凝土搅拌机的成本至少有35至40。除了在冲击磨料操作介质，损害混频器的寿命的因素包括贫穷可靠性和缺乏操作建议，考虑到动态的磨损。的耐磨损性的材料必须是区分从混合器元件的耐磨性新界东北（结构的耐磨损性）。其他条件相等，该材料的耐磨损性依赖于它的属性，而结构的磨损电阻取决于设计和运行参数。最常用的方法，延长寿命快速磨损部件耐磨的使用材料和硬化;的工作表面制造或修理的过程中。资源节约ING的技术许可证，生产效率提

5、高作为一个结果，减少了40或更多，机的修理。在确定即兴的有效性的耐久性材料科学的方法，可用所需的设备的能力，必须考虑到帐户。必须考虑到的磨损动态在确定最好的设计和歌剧的帐户周志武参数4-6。在目前的工作中，我们调查的零组件的磨损动力学在俄罗斯生产的单轴混凝土搅拌机（SB146，BSM26 0.5，26 1.0和BSM混频器）和在其他地方（ELBA混频器）的中央科学研究院26日在俄罗斯外交部国防部和在NPO ELLIPS。操作测试数据，混凝土搅拌机允许组件识别大多数悬浮磨损和故障。这些组件该限制搅拌机生活的刀片;张室衬里和闸阀的显示收费系统。组件的磨损是很大程度上取决于它们的设计和，特别是的工作

6、表面的形状。建立机的磨损动态实验中，使用在con是不溶的混合物克里特岛。这些颗粒是接近四分体和立方体，确保相当大的混合强度和耐久性在实践中。受损最严重的混频器康波的平均数据在磨损间接当今的流体混淆技能已进人快速生长时代，经过近一个世纪的实验研究和理论探索。并积累了大量可用于分析和预测混淆系统的假想经验和关联式。但由于流体混淆系统的多样性和物料流变特性的复杂性，目前对于搅拌装备的选型和假想还主要依靠经验和实验，对其利害很难用理论预测，对于能耗和生产成本，只能在一定范围的生产拆卸上进行对比后才华分出高低。另外对搅拌设备的放大规律至今仍无足够的熟悉，缺少实际领导。因此从更微观更本质的角度，采用进步前

7、辈的测试手段和打算流体力学方式，获取搅拌设备中的速度场、温度场和浓度场，不仅对搅拌与混合设备的优化假想具有主要的经济意思，而且对放大和混合的基础研究具有实际的实际意思。混凝土搅拌机的工作表面的磨损分布在叶片主要由变化可以解释在混合气压力在工作的优势。由于叶片移到一个圆，该混合物不仅在移动也沿着混频器轴的方向时，刀片被对齐在35的旋转的平面。在不同的高度研磨混合物的准备分数的组合物，（变薄）的磨损叶片弯曲，扭曲他们的个人资料，并甚至断裂。因此，在轴的径向磨损增加的垂直由1°2°，而校准倾角的形状变化叶片的磨损增加至25°35°的倾角，的能量消耗的增加。增加

8、在这些角度减少的轴向分量和方位的力量。 脉动和随机湍流给流速测量带来了很大困难。期的流速测量方法如毕托管、电磁流速计、压电探头和热线或热膜风速仪等， LDV/PIV测量技能搅拌设备内流速的正确丈量是一件复杂的任务。这是由于搅拌设备内的固定是三维和高度不稳定的湍流。都由于插人流场中的探头而使流动受到烦扰。20世纪80年代以来，国内外开始利用激光多普勒测速仪来测量搅拌釜内流场。LDV丈量是某一测点处一段时间内进行的因此所测速度是时均定量值，通过对搅拌釜中每一点的测量可以或许得到全体流场。但由于这些测量不能同时执行，是以LDV不能用于研究非稳态流动。为了研究时变流动，必须采用更先进的粒子成像测速仪可

9、在瞬间得到全体流场分布。其原理是搅拌设备由一狭缝激光束照耀，用两个脉冲激发光源，得到粒于场的两次曝光图像，接着从曝光时间内粒子的位移打算出速度场。但PIV技能开拓仍未完善，尚处于应用初期，目前还不能很好地测量高速湍流下的湍流参数。应用LDV测量技巧，可以或许准确获取搅拌釜中丰富的新闻如时均速度场、湍流强度场、雷诺应力场、剪切速率场，并可进一步打算得到宏观特色参数如排量和功耗等。因此今朝LDV测量数据的一个主要用途就是考证模子的仿真结果和供应模型边界前提。近几年LDV还被用于测量多层桨的搅拌特征，如排量和循环流量等。由于在单层搅拌器条件下所采用的测量排量的粒子跟踪法，多层桨条件下是不适用的而不能

10、从本质上熟习混淆与流动， CFD模拟技巧LDV仅仅供给了一些重要参数如排量准数、时均速度和脉动速度的分布等。无法改变日前这种依靠经验来放大的近况。因此采用打算流体力学的方式，来模拟和预测不合几多尺寸和操作条件的搅拌设备中详细的流动和混合特性，流体混淆技巧的生长趋向。搅拌设备内流动数值模拟目前应用最广泛的对搅拌器采用黑箱模型履行稳态分析，即由实验测得搅拌器四处虚构概况的速度场作为边界条件或将桨叶对流体的传染感动看作流体动量的产生源。从数值打算来看，黑箱模型具有简便、方便等特点，能较准确地预报搅拌器在不合条件下的运动特征，但该方法需要实验数据作为桨叶边界条件，因此不能用于多相流体系的模仿。CFD最

11、重要的利用（也是CFD技巧的最主要优点）对流场的剖析，可以或许明白在不合搅拌器的型式、尺寸、离底距离等条件下，流场对混合、悬浮和分散等过程的影响，即CFD固定、能量耗散等的打算可视化。从而利用户可以或许直观地了解釜内的混淆情形，帮助用户判断已存在系统中的成绩，引导用户履行搅拌器的优化设想，消除死区，判断加料口位置等。目前外洋的专业混淆设备公司己经利用CFD技能优化搅拌器的几多尺寸，开辟了第二代高效轴向流搅拌器。CFD另一个主要优点就是模子的设备大小无关性，一旦它被验证可以或许公平准确地描述搅拌反应器过程，就被用于放大，以估量放大后的棍合和反应性能。跟着CFD技巧的成长，可压缩性流体和一些简单的

12、非弹性粘性流体在商业体系中已经可以或许模仿。目前多相流（特别是气-液体系）混杂的CFD模拟也得到长足成长，但与实际应用仍有相当距离。 E. M. R. Fairbairn Materials and Structures, 1999原文Mixing and mixing technology of understanding Can perhaps measurement opaque medium flow field. EPT obligations the reasonable and medical test instrument similar CT. Measured stirre

13、d tank or pipe outside wall a group has been attached with a week, electronic sensor only 816 process faults imaging skills electronic process faults imaging technology EPT a multiphase flow system of non-contact detection in real time and visualization technology. The sensor is rectangle stainless

14、steel electrode piece, is both transmitters and receivers. Kettle or pipe is not to have two kinds of electrical conductivity, capacitance rate (the material (not) conductivity of liquids, gases and solid, liquid and solid) and then in a regular pulses, all can infect touched the adjacent the voltag

15、e sensor combination by data acquisition unit sends them back to the computer. Intend to machine will record all electrode signals and sequence, and USES the image reconstruction skills reply Renaissance out the cross-section or pipeline cauldron image can be obtained, topped 100 frames per second i

16、mage. If use of multi-sensors to not highly fulfill fault, it may be in imaging techniques under the image reconstruction, establish the kettle or auxiliary piping 3d images and solid modeling. EPT system without radiation hazards, price cheap and easy to make, response speed fast and can perhaps th

17、an CT industrial real-time process request meets. But image analysis degrees lower than CT. Because EPT can perhaps accurately measure the flow region, stir reactor velocity and gas and solid component concentration distribution, and these data from space and time can be used to verify the two aspec

18、ts of heterogeneous system confuse model and CFD mold and therefore EPT skills can be applied directly to optimize the imaginary and operation, agitator with electronic skills, image reconstruction algorithm and going to the growth of computer hardware, EPT also will be used to process line monitori

19、ng and control. The performance of concrete mixers depends on the wear of their components. Accordingly, their life and performance may be improved on the basis of the theory and practice of structural wear resistance .This entails dynamic study of the wear. In highway construction, materials of ele

20、vated wear resistance are generally chosen . The resulting improvements are not great. Economic considerations call for other approaches.The operation of concrete mixers is most affected by impact abrasive wear of the blades and the chamber lining, especially at high pressure, temperature, speed,or

21、productivity .For existing concrete mixers, repair costs for worn components largely determine the overall operating costs. Experience in the production of structural mate rials shows that downtime for wear related repair amounts to 4548% of the total downtime. Such problems account for 3841% of the

22、 labor costs of repair each year, while expenditures on the repair and replacement of worn and blades and lining components correspond to at least 3540% of the concrete mixers cost. Besides operation in an impact abrasive medium, factors impairing the mixers life include poor reliability and the lac

23、k of operational recommendations that take account of the wear dynamics.The wear resistance of the material must be distinguished from the wear resistance of the mixer component . Other conditions being equal, the wear resistance of the material depends on its properties, while the structural wear r

24、esistance depends on the design and operational parameters.The most common methods of extending the life of fast wearing components are the use of wear resistant materials; and hardening of the working surfaces in the course of manufacture or repair . Resource saving technologies permit increase in

25、productivity of machines by 40% or more, as a result of reduced repairs.In determining the effectiveness of improving durability by materials science methods, the availability of the required equipment must be taken into account. The wear dynamics must be taken into account in determining the best d

26、esign and operational parameters 46. In the present work, we investigate the wear dynamics for the components of single shaft concrete mixers produced in Russia (ELBA mixers) at Central Scientific Research Institute 26 of the Russian Ministry of Defense and at NPO The operational test data for the c

27、oncrete mixers permit the identification of the components most susceptible to wear and failure . The components that limit mixer life are the blades (B6); the sheets of chamber lining ; and the gate valve of the dis charge system . The wear of the components is largely determined by their design an

28、d, in particular,the shape of the working surfaces.The wear dynamics is established by machine experiments, using mixtures that are insoluble in concrete. The grains are close to tetrads and cubes, considerable mixture strength and durability in practice. We measures the parameters proposed in Table

29、 1. Mean data for the most damaged mixer components in wear.The wear distribution over the working surfaces of the blades may be explained primarily by the variation in mixture pressure over the working edge. As the blade moves over a circle, the mixture is shifted not only in the direction but also

30、 along the mixer axis when the blade is aligned at 35° to the plane of rotation. In the preparation of highly abrasive mixtures of different fractional composition, the wear (thinning) of the blades leads to bending, distortion of their profile, and even fracture.Thus, diametric wear of the sha

31、ft increases the vertical inclination by 1°2°, while the change in shape of the worn blades increases the inclination to 25°35°,with increase in the energy consumption. The increase in these angles reduces the axial component and the azimuthal force. Consequently, the circulation

32、 of theToday's fluid confusing skill has been into rapid growth era, after nearly a century of experimental study and theoretical exploration. And accumulated the massive can be used for analysis and forecast of hypothetical experience and confuse system associated type. But because of the diver

33、sity and fluid confusing system complexity of the rheological properties of materials for mixing equipment, at present the selection and imaginary still rely mainly on the experience and experiments, the theoretical prediction is difficult to use the concern for energy consumption and production cos

34、t, only in a certain range of production remove after comparing ceded the talent level. In addition, mixing amplification device rules still without enough familiar, lack of real leadership. Therefore, from the Angle of more micro more essence, the progress of testing means and predecessors to fluid

35、 mechanics, obtain the way agitate equipment velocity and temperature field and concentration field, not only to the optimization of mixing and mixing equipment is the main economic hypothetical meaning, but also for the basic research of the amplifier and mixed with the actual practical meaning. Pu

36、lsation and random turbulent flow measurement to bring very great difficulty. The velocity measurement methods such as period of Picasso custody, electromagnetic flow meter, piezoelectric probe and hot film anemometer, LDV/PIV measuring the velocity agitate equipment inside skill correctly measure i

37、s a complex task. This is due to the fixed within agitate equipment is three peacekeeping highly unstable turbulence. All because the probe and inserted flow field that flow harassed. Since 1980s, the domestic and international began using laser to measure stirred tank internal flow field. LDV measu

38、rement is a point in the period of time within which nobody measured speed are therefore quantitative values, through to the stirred tank in every bit of measurement can maybe get all the flow field. But because these measurement cannot simultaneously execute LDV cannot be used in the study, is the

39、unsteady flow. In order to research the time-varying flow, must adopt more advanced particles in moments imaging velocimeter to get all the flow field distribution. Its principle is a slit by mixing equipment with two pulse laser shines, stimulate illuminant, get grain in field, and then from exposu

40、re image twice within the time exposure to a particle velocity field. Displacement But PIV skills development is still not perfect, is still in the initial stage, at present it cannot be used well under high-speed turbulent measurement of turbulent parameters. Application LDV measurement techniques,

41、 can probably accurate access stirred tank, rich in news like time-averaged velocity field, turbulence intensity and Reynolds stress field, shear rate field, and further to intend to get macro characteristic parameters such as displacement and power consumption, etc. So tonight LDV measurement data

42、a main purpose was to textual research of mold simulation and supply boundary premise. In recent years LDV is also used to measuring layer blades mixing characteristics, such as displacement and circulation flow rate, etc. Because single blender conditions in the measuring displacements particles tr

43、acing method, multilayer oar conditions is not applicable And not from essentially to familiar with confusion and flow CFD modeling skills, LDV only supply some important parameters such as displacement when ZhunShu, both speed and pulse of speed distribution, etc. Can't change has this kind of

44、situation to enlarge by experience. So the way by going to fluid mechanics, to simulate and predict how size and operating conditions are detailed in the mixing equipment of mixed properties, fluid flow and the growth trend. Confused skills Mixing equipment internal flow numerical simulation of curr

45、ent of the most widely used by the black box model mixer performance by the experimental steady-state analysis, i.e., measured the speed of fictional around general mixer game as boundary conditions of fluid or will blades moved as fluid transmission of the produce source of momentum. Judging from the numerical model, the black box to is simple, convenient wait for a characteristic, can accurately forecast blender in disagreement condition chara