(505c) Direct Meso-Scale Simulations of Flexible Fibres in Turbulent Liquid Flow

A procedure for direct, meso-scale simulations of flexible fibres immersed in liquid flow is introduced. The fibres are composed of chains of spherical particles connected through ball joints with the bending stiffness of the joints as a variable. The motion of the fibres and the liquid is two-way coupled with full resolution of the solid-liquid interface. First the simulation procedure is validated by means of an analytical solution for sphere doublets in zero-Reynolds simple shear flow. Subsequently we use the numerical method to study inertial flows with fibres, more specifically the interaction of a fibre with isotropic turbulence thereby focussing on the dynamics of bending and stretching of the fibre as a result of the erratic flow structures surrounding it, and on the flow-induced forces and torques in the fibre joints.