Low-frequency acoustic scattering from a trailing vortex

Abstract

The cross section for the scattering of low-frequency (∼ 100 Hz) sound by an aircraft trailing vortex is computed using the Born approximation. The predicted cross section is large enough to permit size and strength measurements. Although precise location of a vortex is better done with high-frequency refraction, a monitoring system based on low-frequency acoustic radar is possible, and a system combining the best features of each is also feasible.