外文翻译-平板式离心机中微粒沉淀速度的测量.doc

1、毕业设计(论文)外文资料翻译院 系专业学生姓名班级学号外文出处Journal of Engineering Physics and Thermophysics指导教师评语：指导教师签名： 年 月 日Journal of Engineering Physics and Thermophysics, Vol. 76, No. 4，2003MEASUREMENT OF THE RATE OF SEDIMENTATION OF FINE PARTICLES IN A PLATELIKE CENTRIFUGE UDC 532.584.22:53.082.13 J. G. Dueck,D，Yu. Klli

2、mnik, L. L. Min,kov，and T. NeesseAbstract:The data of experimental investigation of the process of settling of fine particles in a platelike centrifuge have been given. The results obtained on sand and water have shown a nonmonotone character of the relative rate of sedimentation as a function of th

3、e total coiieeHtrdiion of particles and the presence of the effect of a higheMhan-average settling rate for the finest fractions. The methods of measurement of the sedimentation of fine particles are discussed, the experimental procedure is described, and systematic experimental errors are analyzed.

4、Key words: Plate type centrifuge precipitation particles Sedimentation, or the settling of a solid phase, occurs in many processes involving a suspension. Thus, sedi-mentation results in the clarification of water, used in water purification and water preparation, which is largely re-duced to the pr

5、oblem of separation of the solid suspended phase from the liquid phase. Sedimentation, or settling, favorably compares with other methods of purifying water, as, for example, filtration, floatation, etc., in its simplicity of implementation and low cost. This paper try to through the experimental st

6、udy latex body deposit and in the process to determine the influence of the interaction between particles. The method of determination of deposition rate. Determination of fine particle deposition velocity of the most simple method is tracking separation pure liquid level and the sedimentary area a

7、vertical cylinder), also is full of sediment suspension area. This method has obvious regional hypothesis between boundary exists, its not real, especially for the particles. In addition, in this way, the conclusion is that the suspension as well on the basis of quality, that is without isolation. T

8、his method in addition monodisperse suspending liquid cases must be correct. We record the um 10 the size of particle deposition, its density and carrier liquid (water) are only 2-3 times, its speed only a few microns per second. In order to speed up the sedimentary process we can use other quality

9、force, first of all, centrifugal force in this case of measurement analysis more difficult than into vertical cylinder. Originally used by measuring the time between two points along the deposit in the direction of the difference in the pressure of the indirect measurement method of deposition rate.

10、 The statistics of measured pressure difference between two points with the suspension unit volume average density in proportion. Suspension or the presence of more or less hierarchical situation, we can observe differential pressure change curve of inflection point; The inflection point correspondi

11、ng to a certain size fraction of frontal through the measuring instrument of time. Is monodisperse suspension for, sedimentary forward two through the measured pressure is the first and second inflection point. The distance between the inflection point and the difference between the number of instru

12、ctions that we can calculate deposition rate. Bickert, use this way to measure in a centrifuge and deposition rate that many valuable results. Especially some suspending liquid concentrations and arrest the presence of sedimentary was confirmed by S again. At the same time, with the pressure measure

13、ment of different size particles of pit product speed is relatively difficult, due to suspension of segregation generally not too obvious, its form take more dispersed suspension float liquid. In dealing with the results need to a smooth function digital derivation, it is an error system one of the

14、reasons. Based on the sample in the process of two inflection point in particle size analysis and adapted to the more dispersed suspension of a determination of the deposition velocity method has been put forward. In their real - Kumar, etc in the use of the mobile suspension cylinder. Liquid mass b

15、alance formula is U0S0 1 - c (0) = UzSz 1 - c (z) and in the process of two cross section in particle size grades, Kumar, got a different grain size grade particle deposition rate, it is z = 0 point liquid velocity of flow U0, cross sectional area S0 and Sz, first I size level indicator shows that the particle density, and the cross section place particle c total volume capacity control. By initial cross section and cross section z place samples and test t