Surface waves in nonsquare containers with square symmetry

Abstract

Experiment and theory for surface waves in square containers suggest that the effective symmetry may be larger than the geometric symmetry of the container cross section. The extra symmetries complicate the construction of normal forms and appear to stabilize effects in the experiments that would otherwise be nongeneric. These symmetries may be directly observed if the sidewalls are deformed to a nonsquare cross section that retains square symmetry. The effects of such a deformation are analyzed.