Irregular Model

Applications:

Chemical, polymer, pharmaceutical, and natural powders; toners, gypsum, food condiments; any sample whose particles do not conform easily with any of the other shape models, or for which data on surface roughness is needed.

Available measures:

• Feret Width
• Feret Width is the smallest possible spacing between parallel lines that contact but do not intersect the shape. Feret Width often agrees closely with sieve data.
• Feret Length
• Feret Length is the largest possible spacing between parallel lines that contact but do not intersect the shape.
• Feret Aspect Ratio
• Feret AR is the ratio of Feret Length to Feret Width.
• Surface Uniformity
• Surface Uniformity is a measure of the amount of local fluctuation in the particle cross-section's perimeter. 1.0 means no surface roughness; lower values represent greater degrees of roughness.

Images showing Feret Length values