Nonlinear flow response of flexible fibers driven by Stokes flow

The fuzzy, flexible fibers attached to biological surfaces not only reduce drag but also undergo nonlinear deformation under shear flow, and the deformation of these fibers in turn affects fluid flow. This phenomenon is increasingly attracting attention. Due to the complexity of fluid–structure interaction problems, existing analytical solutions such as perturbation methods, integral solutions, and series expansions are still unable to fully address this issue. To tackle this problem, this paper uses COMSOL finite element software for numerical calculations, effectively simulating the interaction between fibers and fluid flow. The results show that this method matches experimental data within a certain velocity range, extending the scope of previous studies and confirming the −1/2 scaling law at higher velocities. Furthermore, the study explores the bending deformation of elastic fibers and the flow field under different fluid loads. This paper provides a new approach for using finite element simulations to model the nonlinear deformation of such fibers, along with visual analysis, which is applicable to similar fluid–structure interaction problems and can provide valuable insights for future scientific research and engineering applications.