Developmental study of a new technique to classify submicron particles

亚微米颗粒分级新技术的发展研究

• 批准号: 03555037
• 负责人: NAKABAYASHI Koichi
• 金额: $ 11.07万
• 依托单位: Nagoya Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03555037/
• 关键词: Classification; Submicron Particle; Almost Rigidly Rotating Flow; Stewartson Layr; Ekman Layr; Interior Region; Particle Motion; Partial Classification Efficiency; ステワートソン層; サブミクロン微粒子分級; 分級性能; せん断層

We have studied a new classifier using the almost rigidly rotating through-flow between rigidly totating housing and rotor, and have obtained the following results.1. Theoretical results(1) In the interior region, the axial velocity depends on slopes and curvatures of the housing and rotor walls, while the azimuthal velocity depends only on the slopes.(2) The ratio of the Ekman transport on the housing to that on the rotor is determinated by the ratio of the function of housing's slope to that of the rotor's.2. Experimental results(1) The condition of occurrence of a steady axisymmetric regime of the flow is epsilon(〕SY.ltorsim.〔)1.6E^<0.46>, Where epsilon and E are Rossby and Ekman numbers.(2) Velocity distributions of the interior region agree with the theoretical results.(3) The Stewartson layr constitutes of the inner layr with a strong axial flow and the outer layr with a weak reverse flow.(4) We got excellent classification efficiency (sharpness index * 1.5) for the case where the feed is supplied only within the Ekman layr on the rotor.3. Computational analysis(1) A computational code to simulate the almost rigidly rotating through-flow between the coaxially rotating rotor and housing and a computational code to analyze motion of particles in the flow are constructed.(2) In the analysis of the almost rigidly rotating through-flow between the rotating disk and cylindrical tank, we have numerically considered the mechanism of the present classification technique.(3) Theoretical and experimental results are confirmed by the computational analysis.(4) Almost all particles at the inlet go to Stewartson layr through Ekman layr.(5) Coarse particles go to rigidly rotating region by the effect of centrifugal force at Stewartson layr.(6) Particle classification efficiency are specified by a parameter Dp/^<0Eepsilon>0 (Dp ; diameter of particles, E ; Ekman number, epsilon ; Rossby number).

本文研究了一种新型分级机，采用刚性旋转机壳与转子之间几乎刚性旋转的通流，得到了以下结果。理论结果(1)在内部区域，轴向速度取决于壳体和转子壁面的斜率和曲率，而方位角速度仅与斜率有关。(2)机壳上的艾克曼输运量与转子上的艾克曼输运量之比由机壳斜率函数与转子斜率函数之比决定。实验结果(1)流动出现稳定轴对称状态的条件为epsilon(] SY.ltorsim. [)1.6E^<0.46>，其中epsilon和E为rosby数和Ekman数。(2)内部区域的速度分布与理论结果一致。(3) Stewartson层由内层强轴流和外层弱逆流组成。(4)对于仅在转子上的Ekman层内进料的情况，我们获得了极好的分类效率（锐度指数* 1.5）。(1)建立了模拟同轴旋转转子与机壳间几乎刚性旋转通流的计算程序和分析流动中颗粒运动的计算程序。(2)在分析旋转圆盘与圆柱槽间几乎刚性旋转的通流时，我们从数值上考虑了这种分级技术的机理。(3)计算分析证实了理论和实验结果。(4)入口颗粒几乎全部通过Ekman层进入Stewartson层。(5)粗颗粒在斯图尔特逊层离心力的作用下进入刚性旋转区。(6)颗粒分级效率由参数Dp/^<0 eepsilon > （Dp；颗粒直径，E； Ekman数，epsilon； Rossby数）表示。

项目成果

中林功一: "準剛体回転成層流を用いた微粒子分級に関する数値的研究" 日本機械学会講演論文集. 943-1. 48-50 (1994)

Koichi Nakabayashi：“使用准刚性旋转分层流进行颗粒分类的数值研究”，日本机械工程师学会论文集 943-1（1994 年）。

Youhei Morinishi: "Computational method for almost rigidly rotating flow." Trans.Japan Soc.Mech.Engrs.(in Japanese), Ser B. vol.60 (to appear). 572 (1994)

Youhei Morinishi：“几乎刚性旋转流的计算方法。”

Koichi Nakabayashi: "Numerical study of classification of fine particles on almost rigidly rotating flow" Prepr.of Jpn.Soc.Mech.Eng.(in Japanese). No.943-1. 48-50 (1994)

Koichi Nakabayashi：“几乎刚性旋转流上细颗粒分类的数值研究”Prepr.of Jpn.Soc.Mech.Eng.（日语）。

中林 功一: "回転2球流れの準剛体回転成層流" 日本機械学会講演論文集. 910-62. 355-357 (1991)

Koichi Nakabayashi：“具有两个旋转球体的准刚性旋转分层流”日本机械工程师学会会议记录 910-62 (1991)。

Koichi Nakabayashi: "Almost rigidly rotating flow between two concetric rotating spheres." Prepr.of Jpn.Soc.Mech.Eng.(in Japanese). No.910-62. 355-357 (1991)

Koichi Nakabayashi：“两个同心旋转球体之间几乎是刚性旋转的流动。”