Diffusion-limited aggregation and viscous fingering in a wedge: Evidence for a critical angle
نویسندگان
چکیده
We show that both analytic and numerical evidence points to the existence of a critical angle of h'60° –70° in viscous fingers and diffusion-limited aggregates growing in a wedge. The significance of this angle is that it is the typical angular spread of a major finger. For wedges with an angle larger than 2h , two fingers can coexist. Thus a finger with this angular spread is a kind of building block for viscous fingering patterns and diffusion-limited aggregation clusters in radial geometry. @S1063-651X~98!10506-8#
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