چكيده به لاتين
Abstract:
Simplified models of the vehicle are suitable tools for the optimization of vehicle primary structures in the early phase of design. In this paper, a simplified model of a Sedan vehicle is provided which, beam members and panels are substituted by 1D-beam elements and big shell elements, respectively. In order to validate the static accuracy of the simplified model, torsional and bending stiffness for Full Finite Element models of the vehicle and simplified models are calculated. The results show high accuracy of the simplified models in comparison with the Full Finite Element model in bending and torsional stiffness prediction. The strong influence of B-pillar on the stiffness of the simplified model is obvious in the torsion and bending tests. The simplified model can be used to perform an optimization in which the design parameters are the cross-section dimensions and thickness of the B-Pillar. The L27 orthogonal array with the grey relational analysis are used for sensitivity analysis and determining the optimal design parameters. In this analysis, cross-section dimensions and thickness of B-Pillar are considered as design variables; weight, torsional and bending stiffness also presented as the objective functions. Furthermore, the ANOVA method is used to analyze the variance and determination the significance of design parameters on objective functions. Eventually, by applying multi-criteria decision-making methods (e.g. NIP, Topsis, SVCB) through Taguchi orthogonal array designs, some different design points are selected and compared with others. According to the results, using Topsis methods, 40% weight reduction in B-Pillar is gained without any significant change in bending and torsional stiffness of the body the base model.
Keywords: Simplified Model, Full finite element model, Bending stiffness, Torsional stiffness B-Pillar, Taguchi, Multi-criteria decision-making methods
