Lateral instability in normal viscous fingers.
We study a low-amplitude, long-wavelength lateral instability of the Saffman-Taylor finger by means of a phase-field model. We observe such an instability in two situations in which small dynamic perturbations are overimposed to a constant pressure drop. We first study the case in which the perturbation consists of a single oscillatory mode and then a case in which the perturbation consists of temporal noise. In both cases the instability undergoes a process of selection.
Ledesma-Aguilar
R
R
Departamento de Física y Química Teórica, Facultad de Química, UNAM Ciudad Universitaria, Mexico DF 04510, Mexico.
Quevedo-Reyes
M
M
Corvera Poiré
E
E
Hernández-Machado
A
A