Abstract

This study focuses on the effects of bed-height and number of revolutions on the granular mixing performance with an objective to derive a mathematical relationship between mixing performance and number of revolutions. The simulations were carried out in a rectangular box in which three fill-levels and up to 15 blade revolutions were used. Blade forces were observed to have a direct relationship with the fill-level while mixing performance had an inverse relation and decreased with the increase in fill-level or bed-height. Mixing performance increased with the increase in the number of revolutions almost exponentially in the beginning. After around 12 blade-passes, the change in mixing performance was not significant, i.e., the mixing index value reached an asymptotic value. A mathematical relationship was derived for a quick estimate of mixing performance after given number of revolutions. The findings are significant and have direct industrial applications as they can best predict the mixing efficiency and residence times for the mixer. The proposed mathematical relationship can be effectively used for any industrial batch mixer employing blade movement or rotation and reduce the mixing costs by a significant factor.

摘要

本研究侧重于床高和转数对颗粒混合性能的影响，目的是推导出混合性能和转数之间的数学关系。模拟在一个矩形盒子中进行，其中使用了三个填充水平和多达 15 次叶片旋转。观察到叶片力与填充水平有直接关系，而混合性能有反比关系，并随着填充水平或床高的增加而降低。开始时，随着转数的增加，混合性能几乎呈指数增长。在大约 12 次叶片通过后，混合性能的变化并不显着，即混合指数值达到了渐近值。在给定转数后，推导出一个数学关系，用于快速估计混合性能。这些发现意义重大，并具有直接的工业应用，因为它们可以最好地预测混合器的混合效率和停留时间。所提出的数学关系可以有效地用于任何采用叶片运动或旋转的工业批量混合器，并显着降低混合成本。