Fig 4. Initial configuration and configuration after 20 h of stencil removal showing the formation of fingers according to the numerical simulation of the model.

(a) Full view, (b) zoom. Initial box size is 1.6 mm², P⁰ = 10, A⁰ = π, and shape index p⁰ = 5.65. Parameter values are those in Table 1. See S1 Video.