流れの可視化を利用した風力分級器の設計と性能解析

抄録

This paper describes of a method for the design and analysis of a pneumatic classifier by flow visualization, using a magnified model.
For the design and analysis of a pneumatic classifier, it is neccessary to know the flow field. Flow visualization by small mist tracer is an easy way to know a flow field.
If tracer particles are thrown into the actual classifier, particles deviate from the stream by inertia force. So it is not possible to look at the real flow.
However, using a sufficiently magnified model, tracer particles do not deviate from the flow. It then becomes possible to investigate the real flow.
A model, 10 times larger than the virtual-Impactor type classifier was made. And using the results of the flow visualisation, the shape of the wake was determined.
It is assumed that the wake is a rigid body, and the main flow is the potential flow. By the S. O. R. method, it is possible to calculate the flow field. By solving one particle's dynamic equation, it is possible to obtaine the trajectory of the particles of each diameter and the partial classification efficiency. These calculated results are in approximate agreement with the experimental results.
Afterwards, using the magnified model, a search for the shape of a classifier which has good characteristics is undertaken. One example of a classifier which was searched for is shown.