… We believe that the theory of these instabilities must start with the separation zones, … ripple
troughs. These might be prone to instabilities7 like the Rayleigh–Plateau ‘sausage’ instability (…

… The sand ripples one observes on a beach at low tide are an example: These ripples were
… deposition, the instability saturates, and the sand flux and elevation profiles vary in phase. …

… Ripple formation on the sand bed is considered in this paper as an instability phenomenon
of the fluid-granular bed interface governed by the two dynamical equations [Eqs. (4) and (10)…

… and a dune-scale instability could result. Some investigators … argue that both ripple and
dune instabilities result, however, … finite depth flow over a bed of sand. Consider a flow of water …

… of ripples can be predicted by linear analyses even if ripples … This paper addresses the
formation of sand ripples under … scale of the initial instabilities from which ripples are formed. The …

… We also report on secondary instabilities occurring in sand ripples, namely a long scale
modulation of the amplitude and wavelength and its later evolution to a spatial period doubling …

… conveyance of sand in hydrocarbon pipelines and the migration of sand dunes on both Earth
and Mars. A better knowledge of the granular transport and of the associated instabilities is …

… morphology of a rippled sand bed. . . 76 Quantitative morphology of a rippled sand bed. .
80 … found for the spanwise instability affecting small-seale current ripples, recur in Joose-grain …

… Finally, we show that mega-dunes form when the sand bed presents … linear instability
mechanism, and must rather result from the interaction and nonlinear pattern coarsening of ripples (…

… sand ripple instability were based on potential flow models. It was shown [McLean, 1990] that
the instability … study of the formation of 3-D sand ripples under a steady flow. The aim is to …