Transportation of powders using a linear motor device

The theory of linear motors has been formulated for both magnetic and non-magnetic reaction plates and criteria established to assess their performance. The predominant mechanism involved in the transportation of ferromagnetic powders cannot be the same as that in a motor device, because basic calculations show that the induced currents in the particles at 50 Hz are small. Instead, the ferromagnetic particles seem to follow the movement of the travelling magnetic field itself. A study of the phenomena associated with the transportation of powders using linear motor devices has been commenced in a SERC project at Loughborough University of Technology. This paper illustrates the motion of the particles along a linear motor device and also reviews the experimental work done previously, especially that associated with powder cleaning devices. Areas of future research work to be followed are discussed and possible new industrial applications mentioned.