Wrinkling dynamics accelerate due to sudden changes in boundary conditions

We investigate the wrinkling dynamics of a long, flat filament immersed in a viscous fluid subjected to compression at a constant rate. Typical wrinkling dynamics proceed through three stages: initiation, development, and relaxation. The first stage, during which high mode perturbations increase exponentially while the shape and filament tension remain almost unchanged, is notably longer in the linear and nonlinear simulations than in the experiments by Chopin et al. [Phys. Rev. Lett. 119, 088001 (2017)10.1103/PhysRevLett.119.088001]. We propose that sudden environmental changes introduce extra high-frequency perturbations beyond thermal fluctuations, which significantly accelerates the first stage. This effect is universal and inevitable for similar processes given the experimental conditions. Finally, we analyze the relationship between the initial perturbations and the duration of the first stage.