SPIRAL WAVES IN DISPERSIVE MEDIA

The Lighthill kinematic approach is applied for the description of sta nding waves generated at circular motion of a point source in a disper sive medium. A single nonlinear ordinary differential equation is deri ved. Numerical calculations are performed for different dispersion rel ations. The spiral shape of waves and the existence of special points for wave crests are the main peculiarities of solutions obtained. A po ssible application of the kinematic approach to the description of spi ral galaxies and other physical phenomena is demonstrated.