Numerical model for the dynamics of a coupled fly line/fly rod system and experimental validation

A model is presented that describes the two-dimensional dynamics of the coupled system composed of a fly rod and a fly line. The fly line is modelled as a long elastica that is subjected to tension, bending, aerodynamic drag, and weight. The fly rod is modelled as a flexible Euler–Bernoulli beam possessing two degrees of freedom: a rigid-body mode, and a flexible-body mode. The line and the rod are coupled through the boundary conditions at their interface. The resulting initial two-point boundary-value problem is solved numerically using a finite difference algorithm. The numerical solutions for an overhead cast are computed using experimental data as the input for the motion of casterʹs hand. The shape of the fly line and the position of the fly rod are compared with images captured by video.