The coiling of material is typically performed when a continuous production process of long products is applied. The equations of motion of such a system are non-linear and time-dependent, as some system parameters vary with time and rotation angle. A control volume method has to be used when deriving the equations of motion as mass is flowing into the system and hence changes parameters like inertia and stiffness. Ritz approximations are applied for the deflection of the coiling drum and the longitudinal as well as the transversal vibrations of the moving strip. The present winding model includes the transversal oscillations of the strip and introduces two Ritz approximations for the bending shape. The strip tension force and hence the longitudinal oscillations are coupled to the transversal oscillations by the second order theory. Additionally there is a strong coupling to the vibrations of the coiling unit. Considering the transversal oscillations of the strip some results are given where the coupled oscillations occuring in the rotordynamic system can be seen. For some production and system parameters the computed vibrations are given, where a Runge-Kutta time integration algorithm is used.
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