Modeling the dynamic flow–fiber interaction for microscopic biofluid systems

Microscopic flow–fiber interaction is frequently encountered in biofluid systems. In this paper, we propose a three-dimensional numerical model for such systems, including a spring network model for the elastic fiber, the lattice Boltzmann method for the fluid flow, and the immersed boundary method for the flow–structure interaction. Simulations are also conducted to examine the fiber deformation under constant and sinusoidal shear conditions. While an equilibrium state can be reached under a constant shear, periodic oscillation in fiber shape is observed in a sinusoidal shear flow, at a frequency identical to that of the imposed shear flow. A continuous phase shift of the fiber oscillation is also noticed along the fiber. These simulations demonstrate the potential usefulness of this model in microscopic biofluid and other systems, and further studies are necessary to investigate the dynamic flow–fiber interaction in various flow situations.