DYNAMICS OF A LIQUID COLUMN ARRAY UNDER PERIODIC BOUNDARY-CONDITIONS

We investigate the dynamics of a pattern of liquid columns formed belo w a circular fountain. Traveling domains consisting of drifting asymme trical cells are forced and quantitatively studied. We provide evidenc e of a unique propagation velocity of the domain walls, which increase s with the flow rate but depends on neither the number of moving colum ns nor the fluid viscosity. Similar to the ''printer's instability,'' this velocity is proportional to a natural velocity formed from the st atic wavelength and the frequency of localized oscillations of the col umn position.