Bursting dynamics of viscous film without circular symmetry: the effect of confinement

We experimentally investigate the burstingdynamics of confined liquid film suspended in air and find a viscous dynamics distinctly different from the non-confined counterpart, due to lack of circular symmetryin the shape of expanding hole: the novel confined-viscous burstingproceeds at a constant speed and a rim formed at the burstingtip does not grow. We find a confined-viscous to confined-inertial crossover, as well as a nonconfined-inertial to confined-inertial crossover, at which burstingspeed does not change although the circular symmetryin the hole shape breaks dynamically.