Development of a Customized Beam-to-Shell Element Model Mapping Tool

A customized solution enabling the mapping of fiber orientations represented by beam elements in organic sheet materials from one simulation phase to another of the product development cycle has been developed using python scripting language. The strategy implemented for the mapping of the fiber orientations is based on the modeling approaches used for the input models in both types of simulation. The thermoforming simulation model consists of beam and shell elements representing the fiber and polymer layers in an organic sheet respectively while in the structural simulation, the component is usually modeled using only shell elements. The thermoforming simulation results (a .d3plot mesh) and structural simulation model input mesh are provided as inputs to the so called “BETA Mapper script”. The script segregates elements from each model into discrete volumes enabling parallel processing of the mapping procedure. The centroid coordinates of the elements from each matching cuboid are used to identify element pairs by finding the shortest distance between two element centroids. During the thermoforming process, the fibers, in the warp and weft directions of an organic sheet undergo a relative scissoring motion. In order to take this effect into consideration and to capture non-orthogonal fiber directions, the script is developed to produce three solutions and provides the possibility for mapping various types of part geometries. Developable geometries, which can be unfolded as a flat surface and do not exhibit any relative fiber scissoring, are mapped according to “Solution 1” and the part can then be simulated using assigned orthotropic material properties. “Solutions 2” and “3” implemented in the script, provide a methodology to enable the mapping of fiber orientations in two non-orthotropic directions in a single mesh model, which is not feasible with the generic approach using only one definition of the keyword (*PART_COMPOSITE). Additionally, “Solution 2” implemented in the script provides the user with the flexibility to choose the number of individual parts to be generated during the mapping. The method facilitates the realization of correctly mapped fiber orientations of the warp and weft yarns of an organic sheet in a single mesh model. With its three solutions, the “BETA Mapper script” provides the required data integrity between the different phases of organic sheet virtual product development and enables overall improvement in product design.