A Nonlinear Dynamic Model for Two-Strand Yarn Spinning

A nonlinear dynamic model is established for two-strand spun or Sirospun yarns. The homotopy perturbation method proposed in our earlier work is used to calculated the approximate oscillating periods in the vertical and horizontal directions. The study reveals that the optimal convergence angle of the two strands in equilibrium is 90°, while when the convergence angle is near 127°, resonance occurs.