Screening performance: to first order, the mass capacity of a screen is proportional to which function of the characteristic aperture size S?

Introduction / Context:
Screen capacity depends on open area, aperture size, material properties, and motion. A common heuristic is proportionality to the aperture dimension for similar conditions and media.

Concept / Approach:
For geometrically similar screens and wire diameters scaled with aperture, the open area and passage probability scale roughly with S, leading to a near-linear relation with capacity for the same duty. Strong departures occur with pegging, near-size blinding, and moisture.

Final Answer:
S (linear proportionality)