(77a) A Bonded Sphero-Cylinder Model for Computational Simulation of Large Aspect Ratio, Flexible Fibers

A bonded sphero-cylinder model is developed for computational simulation of large aspect ratio, flexible fibers. In this model, a single fiber is formed by connecting a number of sphero-cylinder segments at their spherical ends using elastic bonds. The model is verified by examining the mechanical behavior of a single fiber subject to external loads. The simulation results of bending, twisting, and stretching deformations of the single fiber are compared with the analytical solutions. Bond damping model is proposed to dissipate the kinetic energy during fiber vibration process. The correlation is established between the macroscopic damping coefficient, which characterizes energy dissipation rate for the whole fiber during vibration, and the damping coefficient for a single bond, which is the input parameter for the simulation.

To illustrate its capability, the developed model is applied to computationally investigate the compressibility of assemblies of fibrous particles. The compression of fibrous materials is frequently encountered in industrial operations, such as briquetting of agricultural materials and processing of wool, cotton and textiles. A better understanding of fiber compression can greatly improve the design of these operating procedures. From the fiber compression simulations, the macroscopic compression properties of bulk material (e.g., bulk compression stiffness) can be measured. The effects of initial particle bed configuration and fiber properties (e.g., aspect ratio, bending stiffness, and friction coefficient) will be explored.