STUDY ON ACCURATE-HIGH SPEED POWDER CLASSIFICATION SYSTEM CONSIDERING PARTICLE CHARACTERISTICS

考虑颗粒特性的精确高速粉体分级系统研究

基本信息

批准号：
15560156
负责人：
NAKABAYASHI Koichi
金额：
$ 2.37万
依托单位：
AICHI UNIVERSITY OF TECHNOLOGY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15560156/
关键词：
SMALL PARTICLE CLASSIFICATION EFFECT OF TRUE SPECIFIC GRAVITY EKMAN NUMBER ROSSBY NUMBER FRACTIONALE EFFICIENCY SCALING LAW CENTRIFUGAL EFFECT PARAMETER GRAVITATIONAL EFFECT PARAMETER 重力効果パラメータ粒子特性と分級収率

项目摘要

WE PROPOSE A NEW WET TYPE CENTRIFUGAL CLASSIFICATION SYSTEM TO WHICH A STABLE AND AXISYMMETRIC ALMOST RIGIDLY ROTATING FLOW CAN BE APPLIED. THE CLASSIFICATION SYSTEM HAS DISTINCTIVE FEATURES IN THAT WE CAN ARBITRARY SET THE RATIO OF THE CENTRIFUGAL FORCE TO THE FLUID DRAG ACTING ON PARTICLES AND CAN THEORETICALLY INVESTIGATE THE CLASSIFICATION MECHANISM FROM THE PARTICLE TRAJECTORIES BY NUMERICAL SIMULATION. WE PREVIOUSLY INVESTIGATED RESULTS OF THE CLASSIFICATION PERFORMANCE FOR VARIOUS THROUGH FLOW RATE AND ROTATION RATE, AND CLARIFIED THE DEPENDENCE OF THE SHARPNESS INDEX AND CUT SIZE ON EKMAN AND ROSSBY NUMBERS FOR THE SPHERICAL PARTICLES FROM ONE-MICRON TO SUB MICRON REGIME HAVING TRUE SPECIFIC GRAVITY NEAR ONE. HOWEVER, THE THROUGHPUT IS SMALL FOR THE SYSTEM. INDUSTRIAL NEEDS ALSO DEMAND MORE ACCURATE CLASSIFICATION OF PARTICULATE MATERIALS HAVING VARIOUS SHAPES AND TRUE SPECIFIC GRAVITY MORE THAN TWO. HENCE IN ORDER TO MAKE THIS SYSTEM PRACTICABLE, WE HAVE TO EXTEND THE SYSTEM TO MORE EFFICIENT ONES.THE OBJECTIVE OF THE PRESENT STUDY IS TO DEVELOP THE CLASSIFICATION SYSTEM TO A NEW TECHNIQUE ON THE CLASSIFICATION SYSTEM SATISFYING INDUSTRIAL NEEDS. WE HAVE OBTAINED THE FOLLOWING RESULTS:1. IN ORDER TO CLARIFY A SCALING LAW ON THE GRAVITY FORCE, WE DEFINE CENTRIFUGAL EFFECT PARAMETER Ce, GRAVITATIONAL EFFECT PARAMETER Ge AND PARTICLE REYNOLDS NUMBER Re. AND WE INVESTIGATE THE RELATION BETWEEN THESE PARAMETERS AND THE DIFFERENCE OF FLUID AND PARTICLE VELOCITIES IN THE STEWARTSON LAYER WHICH IS THE MAIN CLASSIFICATION FLOW FIELD.2. WE CALCULATED THE PARTICLE TRAJECTORIES AND THE PROBABILITY DENSITY DISTRIBUTION OF THE PARTICLES BY THE NUMERICAL SIMULATION. AND WE INVESTIGATE THE CLASSIFICATION MECHANISM IN THE EKMAN AND STEWARTSON LAYERS.3. WE TREAT NEW SYSTEM WITH A SIMPLE SHAPE LIKE A DISK-CYLINDER SHAPE AND EVALUATE ITS CLASSIFICATION PERFORMANCE BY NUMERICAL SIMULATION.

我们提出了一个新的湿型离心分类系统，可以应用稳定和轴对称几乎刚性旋转的流动。分类系统具有独特的特征，因为我们可以任意设置离心力与作用于颗粒的流体阻力的比率，并可以通过数值模拟从粒子轨迹中研究分类机制。我们先前已经研究了各种流量和旋转速率的分类性能结果，并阐明了从一微米到一个接近一个微米的球形粒子到一个微米的球形颗粒的清晰度指数和切割大小对Ekman和Rossby数字的依赖性。但是，对于系统而言，吞吐量很小。工业需求还需要更准确地分类具有各种形状的颗粒物材料，而真正的比重超过两个。因此，为了使该系统可行，我们必须将系统扩展到更有效的系统。本研究的目的是将分类系统开发到满足工业需求的分类系统的新技术。我们获得了以下结果：1。为了澄清重力力的缩放定律，我们定义了离心效应参数，重力效应参数ge和粒子雷诺数re。我们研究了这些参数之间的关系以及Stewartson层中流体和粒子速度的差异，这是主要分类流场2。我们通过数值模拟计算了粒子的粒子轨迹和概率密度分布。我们研究了Ekman和Stewartson层中的分类机制3。我们以简单的形状（如磁盘缸形状）处理新系统，并通过数值模拟评估其分类性能。