FRICTIONAL COLLISIONAL EQUATIONS OF MOTION FOR GRANULAR-MATERIALS AND THEIR APPLICATION TO FLOW IN AERATED CHUTES

Equations of motion and boundary conditions for a flowing granular material, developed in earlier publications, are here extended to allow for drag forces resulting from relative motion of the material and interstitial air. These are solved for fully developed flow down an inclined plane, through which a constant flow of air passes upward. The results are compared with measurements from an experimental aerated chute, in which the inclination of the chute, the flow rate of the granular material, and the flow of air are all varied. Using parameter values from independent measurements, as far as possible, the theory is found to give a good qualitative account of the observed behaviour. With a reasonable assigned value for the one parameter that cannot be determined independently the quantitative agreement is also satisfactory.