Development of nonlinear finite element codes for stability studies of web material with strain state dependent properties

Scope and Method of Study: The objective of the proposed research is to develop user friendly finite element codes that will solve nonlinear instability problems associated with strain state dependent material properties and boundary conditions of moving webs. This code will be unique and will have economic value by helping minimize web material losses.Findings and Conclusions: The results of the work are user friendly finite element codes applicable to the following four cases: for a web encountering a misaligned roller, a web encountering a tapered roller, a web with a central circular discontinuity, and a web with a central circular non uniformity. The codes developed rely on inputs of simple geometry and material parameters which should be apparent to the user. From there on the codes execute automatically in the meshing of the problem, the generation of the elastic and wrinkle membrane elements, and the solution of the nonlinear instability problem. The results from this codes have been shown to compare favorably with test results and results from commercial FE codes