SELF-ORGANIZATION OF 2-DIMENSIONAL INCOMPRESSIBLE VISCOUS-FLOW IN A FRICTION-FREE BOX

The process by which self-organization occurs for two-dimensional inco mpressible viscous flow in a friction-free box is investigated theoret ically with the use of numerical simulations. It is shown by analytica l and numerical eigenfunction spectrum analyses that two basic process es for the self-organization are the spectrum transfer by nonlinear co uplings and the selective dissipation among the eigenmodes of the diss ipative operator, and they yield spectrum accumulation a: the lowest e igenmode. The third important process during nonlinear self-organizati on is an interchange between the dominant operators, which has hithert o been overlooked in conventional self-organization theories and which leads to a final self-similar coherent structure with the lowest eige nmode of the dissipative operator.