A new system has been developed to measure the flow and mixing characteristics of powder mixers. The intensity of the changes of the reflected light from the mixture were measured continuously by a photometer with five sets of optical fiber probes located separately in the mixer vessel. The output signals were processed by an A/D converter and a microcomputer, and the concentration change with time and the degree of mixing at every moment were calculated and displayed on the VDT.
The mixing performance for a high speed agitator-type mixer with a vibrating vessel was investigated by using the present system. The experimental results show that the optical measurement is accurate enough for practical usages, and the developed system is useful not only for evaluation of the mixing performance but also for the measurement of the surface condition of particles.