Influence of the number of detectors by laser scattering method for estimation of particle size

Effect of the number of detectors on an inversion problem of a scattering pattern by laser scattering method based on Mie scattering model has been investigated. The influence of the number of detectors is obtained by comparing a given size distribution and a calculated size distribution by computer simulation and experimental method. An observing range of scattering angles is from 0.0007 to 2.5 rad. A non-linear iteration method is used for calculating particle size distribution. The number of detectors is changed from 6 to 81 elements by the computer simulation. The algorithm of the inversion problem is applied with mean diameters of log-normal distribution in a range from 0.546 to 214 μm at standard deviation of 0.27 and 0.68. Experimental results of certified mono-disperse polystyrene latex standards and a poly-disperse aluminum sample are obtained with 21, 41, and 81 elements detector, respectively. All tests are performed under conditions at diluted aqueous suspensions. Narrow size distribution is influenced by the number of detectors compared with wide size distribution. Not the number of physical detectors but the number of useful detectors affects the algorithm of the inversion problem. When the detector elements are over 20, the influence of the number of detectors is decreased

Effect of blade rotation on particle classification performance of hydro-cyclones

The effects of top blade rotation of hydro-cyclones on particle classification performance were examined experimentally and via a simulation study. It was noticed that the cut size of a hydro-cyclone decreases as the rotational speed of the top plate increases. Compared to the standard case without rotation, the accuracy of classification with top plate rotation increases under the wide range of operational conditions. Newly proposed type-D cyclones with a special blade indicated the smallest cut size with a high accuracy of classification. The increase of classification accuracy is due to the production of outward radial flow near the top plate and this result was simulated by a CFD calculation. The computer simulation also agreed qualitatively with the experimental dat