Question

angle of repose for various materials for good flow

Answer 1

Angle of repose and flow through an orifice ... base) assumed by a cone-like pile of material formed by any of several different methods.

Answer 2

The angle of repose, or critical angle of repose, of a granular material is the steepest angle of descent or dip relative to the horizontal plane to which a material can be piled without slumping. At this angle, the material on the slope face is on the verge of sliding. The angle of repose can range from 0° to 90°.

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