Patterns and spatiotemporal chaos in parametrically forced surface waves: a systematic survey at large aspect ratio

摘要: Abstract A systematic experimental survey of both the primary patterns and secondary instabilities parametrically forced surface waves (Faraday waves) in large system limit is presented. The symmetry pattern (stripes, squares, or hexagons) depends on viscosity ν driving frequency f o . Hexagons are observed at low over whole range despite subharmonic that tends to suppress them. Possible mechanisms for occurrence hexagons single forcing discussed. Boundary-induced distortion absent hexagonal square patterns, but present stripes. Phase defects occur between domains differing temporal phase by π (with respect forcing). Patterns different coexist certain parameter ranges. transition spatiotemporal chaos (STC) patterns. undergo an order/disorder which angular anisotropy Fourier space declines continuously zero. Striped high become unstable via transverse amplitude modulations regions curvature; this instability results a spatially nonuniform mixed state STC with We propose phenomenon may be understood terms critical curvature acceleration. oscillatory also deform stripes within intermediate viscosities.