Abstract : This study is focused on the behaviour of granular media when they are confined between two side-walls.
In a first part we study the influence of the beads/side-wall contact properties on the stability of a granular heap using an external electric field. We also study the behaviour of dynamically stabilised heap (SSH), the angle of repose, the shear rate and the packing fraction as a function of the control parameters: the width between side-walls and the input flow rate .
In a second part we make a large scale experimental study of confined granular flows. By combining two experimental methods we are able to obtain the stream wise velocity profile over 10 decades. We point out that the movement of grains located in the creeping area is intermittent. This result allows us to explain the exponential decrease of the velocity profile with depth and the decrease of the effective friction coefficient obtained numerically.
The topic of the last part is the erosion of a granular heap, when the input flow rate is stopped.