Flow-induced morphological instability of a mushy layer

CORRIGENDUM: Flow-induced morphological instability of a mushy layer

Shear-enhanced convection in a mushy layer

We investigate the effect of an external shear flow on the buoyant instabilities inherent in the directional solidification of a dendritic mushy layer. In the presence of an external shear flow, perturbations of the mush–liquid interface lead to perturbed flow in the bulk fluid that create pressure variations along the mush–liquid interface. These pressure variations drive flow in the mushy lay...

Convective instability of strained layer step-flow

We examine an epitaxial crystal growth model in the context of absolute and convective instabilities and show that a strain-induced step bunching instability can be convective. Using analytic stability theory and numerical simulations, we study the response of the crystal surface to an inhomogeneous deposition flux that launches impulsive and time-periodic perturbations to a uniform array of st...

Three-dimensional instability of a two-layer Dean flow

Stability of a two-layer Dean flow in a cylindrical annulus with respect to three-dimensional perturbations is studied by a global Galerkin method. It is shown that for large inner radius of the annulus ~i! the instability becomes three-dimensional if one of the fluid layers is thin, ~ii! its onset is not affected by possible small deformations of the interface, and ~iii! multiple three-dimensi...

Feedback Instability in a Boundary-layer Flow over Roughness

Linear stability of an incompressible triple-deck flow over a wall roughness is considered for disturbances of high frequency. The wall roughness consists of two relatively short obstacles placed far apart on an otherwise flat surface. It is shown that the flow is unstable to feedback or global mode disturbances. The feedback loop is formed by algebraically decaying disturbances propagating ups...