Web Wrinkling Effects on Web Modeling

In modelling web handling system as controlled dynamic system the model of the web selected can effect system behavior. Webs are membranes capable of resisting tensile stresses but incapable of resisting compressive stresses due to buckling or `wrinkling´. This allows at least two unique web models tobe formed. The first model assumes that the web line tension is large enough that bending of a web, due to a controller or roll misalignment, does not produce compressive stresses. Thus the web can be modeled as a beam in bending. The second model assumes that the web has wrinkled and now must be modeled as a series of ribbons between wrinkles. Results of an experimental investigation are presented to help determine which web model is valid such that an appropriate control strategy can be implemented.