Factors Affecting Angle of Repose

Internal factors are those inherent to powders, or characteristic of the nature of powders. These include particle size, particle shape, and cohesiveness. In general, larger particles have higher angles of repose. However, very small particles may exhibit cohesiveness due to the electrostatic effect, which increases the angle of repose (Ref 31, 32, 33). Because spherical particles have a greater tendency to roll, they typically have smaller angles of repose than irregularly shaped particles.

External factors are introduced by the environment and may include the method of measurement or the presence of other materials (either solid or liquid). The effect of measuring method is clearly evident as discussed above. In general, the more momentum introduced by the measuring method, the smaller the angle of repose. As a consequence, the drained angle of repose is higher than that obtained from the heap formation method.

The angle of repose of loosely packed dry powder may be increased by compacting, as well as by introducing liquid to the powder. Figure 26 demonstrates the significant effect these factors have on the angle of repose (Ref 30, 35).

Fig. 26 Effect of moisture content on angle of repose of loose and compacted coal. Source: Ref 30

Frydman (Ref 36) reported that the angle of repose of potash pellets may be increased by more than 100% by applying a light spray of moisture to the material surface. The effect of the presence of another solid is shown in Fig. 25.

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  • Marco Kuefer
    How does moisture affect angle of repose?
    3 years ago
  • amna
    How powder affect angle of repose?
    2 years ago
  • mary
    What are the factors that can affecting angle of repose?
    2 years ago
  • brhane
    How particle size will influence ngle of repose?
    2 years ago
  • Ponto
    How does size of powder affect angle of repose?
    2 years ago
    What are the factor affecting angle of repose?
    2 years ago
  • senait
    How does moisture content affec angle of repose?
    2 years ago

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