Author(s)

LORENZO FRACCAROLI, CARLO GORLA, FRANCO CONCLI

Abstract

The design process of a ski is characterized by a short time of development due to continuous advancements in the material science and in the manufacturing processes as well as in customer’s requirements. Nowadays, the development process is very often still based on several physical prototypes and trials and Finite Elements Analysis (FEA) is a significant method to reduce times needed. The aim of this work is to develop a reliable numerical simulation of an existing mountaineering ski, able to predict the performance of the real element. For this purpose, an initial mechanical characterization of all the constituents used in the ski manufacturing was performed. Tensile tests in two directions were performed on flat bone-shaped samples laser cut from sheets. Combining the results of the tensile tests with Digital Image Correlation (DIC) data it was possible to approximate the four in-plane (XY) elastic properties, namely, the two elastic modules, the shear module and the Poisson ratio (E_x, E_y, G_xy, ν_xy). The DIC free software used is GOM Correlate. Results of the combined “tensile tests &x#2013; DIC” approach were after verified with FEM simulations reproducing the testing configuration. The digital model of the ski was created starting from the nominal geometry. The whole procedure of modelling, meshing and FE analysis was performed in the open source software Code_Aster/Salome-Meca. Using this kind of software, which code is free to use and modify, permits to reduce costs due to its free license. The real component was tested in a three-point bending and torsion test. This kind of experiments were replicated on the FEM model and results were compared. The comparison highlighted discrepancies of 2.5%–10% with respect to the real component.

Keywords

ski mountaineering, FEM, Code_Aster, DIC, composite materials, Salome-Meca