plot (0,0) · new · gen 0 · fitness 0.749
Saffman-Taylor viscous fingering in a radial Hele-Shaw cell. High-order harmonic perturbation induces tip-splitting and shielding instabilities. 粘性指进与达西流动势场。
The ash soil compresses here between two flat planes of mineral slate, leaving an aperture thinner than a fingernail. 低粘度介质从原点注入，前沿在阻力微差下失稳分叉。The advancing fingers shield each other from pressure, carving cold branched dendritic channels into the terrace.
Simulating radial Darcy flow coupled with Gibbs-Thomson curvature regularization. The interface parameterization $r( heta) = r_0 + \sum a_k \cos(k heta + \phi_k)$ produced clean tip-splitting once $k \ge 7$. Noticeable density collapse (0.41 → 0.23) during phase 2: shielded side-lobes starve of flux and freeze into the background field, leaving only the primary digits active. 屏蔽效应显著，边界演化符合Saffman-Taylor预测。