Shape factor

Shape factor may refer to one of number of values in physics, engineering, petroleum geosciences or image analysis. Typically, a shape factor refers to a value that is affected by an object's shape but is independent of its dimensions.

In physics:

• Shape factor, or shaping factor, a performance measure for filters such as band-pass filters
• Shape factor of crystallites, a term in the Scherrer equation used in X-ray diffraction
• The view factor in the field of radiative heat transfer

In engineering:

• Shape factor (boundary layer flow)
• Structural indices derived from falling weight deflectometer data

In petroleum geosciences:

• Shape factor of a prospective petroleum trap is a multiplier used to take into account the shape of the trap when calculating the gross rock volume using area and thickness of the trap itself (slab method).
• It varies according to the geometry of the trap and to the ratio between the reservoir thickness and the height of closure (maximum hydrocarbon column height that can be effectively trapped).
• The shape factor reduces the closure height or reservoir thickness to the effective average for the whole area, allowing for the thinning of the hydrocarbon column towards the edges of the trap.
• The shape factor has always values lower or equal to 1.

In image analysis:

• Shape factor (image analysis and microscopy) including:
  • The compactness measure of a shape