Description:
The finite-element approach has previously been used, with the help of the ATILA code, to model the subsonic and supersonic waves in immersed waveguides [A. C. Hladky-Hennion et al., J. Sound Vib. 212, 265–274 (1998)]. This method has given a precise account of the experimental results and has shown the major effects. In this paper, a new representation of radiating waves is presented, leading to a simple understanding of the physical phenomenon: radiating waves are propagating with the same phase velocity on the surface of a cone, the axis of which is the wedge direction.