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Automotive fenders is one such example where specialized thermoplastic material Noryl GTX* (blend of Polyphenyleneoxide (PPO) + Polyamide (PA)) has successfully replaced metal by meeting functional requirements. The evolution of a fender design to fulfill these requirements is often obtained through a combination of unique material properties and predictive engineering backed design process that accounts for fender behavior during the various phases of its lifecycle. This paper gives an overview of the collaborative design process between Mitsubishi Motors Corporation and SABIC Innovative Plastics and the role of predictive engineering in the evolution of a thermoplastic fender design of Mitsubishi Motors Corporation's compact SUV RVR fender launched recently. While significant predictive work was done on manufacturing and use stage design aspects, the focus of this paper is the design work related to identifying support configuration during the paint bake cycle.

This paper presents a Finite element analysis (FEA) methodology to predict the behavior of an automotive thermoplastic fender subjected to the e-coat paint bake cycle. Such a methodology, essential for an optimum fender design involves solution of a thermo-viscoelastic problem whose solution is not yet reported in literature. This FEA methodology employed in the early design phase would help in the development of an optimum thermoplastic fender and support strategy. It is shown with help of a case study that the efficacy of different support combinations and their effect on final fender deformations can be predicted virtually very early in the design phase. While this paper presents the methodology and its application using the example of a large body panel (BP) like fender, it can easily be applied for predicting the response of other thermoplastic parts like tailgate and tank flap during the paint cycle.

This paper is motivated by the need to predict deformation behavior of an automotive thermoplastic fender during its residence in e-coat paint bake oven where it is heated by convective currents from blowers. Part - 1 [ 1 ] of this paper, presented a FEA methodology to model the behavior of thermoplastic fender during ecoat bake. Additionally a multiphysics computational procedure to include effect of temperature and stress history was also proposed to enhance the accuracy of the solution. In this paper, we focus on the prediction of temperature history and its influence on fender deformation. Towards this, we present a two-stage thermo-mechanical simulation procedure utilizing CFD and FEA to model the ecoat bake process. While the procedure can model the heating of the fender by convective currents from blowers using CFD, the required flow field data of the ecoat oven is highly confidential.

This paper presents results of mass flow prediction study in progressive bore throttle body (TB), using CFD. A major emphasis of the study has been on capturing the effect of tolerance on clearance area and hence flow predictions, especially at low angles. In addition, effect of viscosity on mass flow predictions has been investigated. Comparison of experimental mass flow obtained from a “manufactured TB” with CFD prediction leads to significant difference, especially at low angles. One reason for this difference is that CFD models based on mean-CAD geometry do not capture the effect of tolerances. To address this difference, an analytical equation for predicting clearance area has been developed. This allows capturing of variation in geometry due to manufacturing. A Design of Experiments (DoE) approach utilizing the analytical work and GE proprietary six sigma tools has been used to capture the effect of tolerances on the clearance area and quantify the variation.