The Flow of Fine Powders

This report consists of an account of work done under IFPRI contract in Cambridge University during the year to December 1987. The principal achievements during that time are:

1. Installing pressure transducers on the flow rig and developing the associated software so as to be able to measure the very low pressure differences occurring.
2. The performance of a series of experiments on a hopper of half angle 15 degrees; the results confirming the observations tentatively reported in the last IFPRI report.
3. The development of a possible theory to explain the observation.

Also included is the programme of work proposed for the rest of the contract.