The next three frames of Fig. 3 showthe changes in the distribution
of the particles as the inclination of the screwconveyor is increased to
30° in 10° steps. Fig. 3(b), (c) and (d) shows the heap in front of the
leading face of the screw blade progressively redistributing as the
inclination of the screw increases, with less material at the bottom
near the casing and more material near the top. The free surface of the
bed of particles becomes increasingly aligned with the angle of the
screw blade. As the inclination of the screw increases more particles