Acoustic-intensity striations below the critical depth: Interpretation and modeling

Abstract

This paper presents a technique for calculating tracks of striations observed in the plot of acoustic intensity versus range and frequency. The striations result from the interference in acoustic propagation below the critical depth. The key of this technique is modeling Lloyd's-mirror interference fringes based on the ray-based description of the normal modes. Then, as the striations are interpreted as sampling fringes at different frequencies and ranges, a method to calculate their tracks is proposed based on the fringe model. Finally, experimental observations of striations are compared with results from the presented technique.