Concept Auto Body Intellectualized CAE Analysis-Research Of 1D Beam Section's Optimization

The concept design phase is the important phase to ensure the performance of auto body. It is hard to make up for the defect leaved by this phase in the next design phase, so this phase is much emphasized in the auto body development flow. Now it is deeply researched by domestic and overseas scholar, especially the auto body development flow based on CAE analysis has been formed, the auto body concept design is becoming systemization and standardization.Through analysis the task and characteristic of auto body structure in concept design phase, VCD-ICAE system is constructed. Its research object is auto body structure in concept design phase. Its aim is to quickly and correctly create the concept auto body structure. It adopts template technique, KBE, parameter technique and data base technique. It comes true the optimization of beam section shape by sensitivity and parameter optimization analysis. It bases on NX platform and integrates intellectual model, FE simulation and parameter optimization technique.The key technique of VCD-ICAE is the parameter optimization of beam and sheet panel of concept auto body. It is well known that the beam is the mainly bear the weight of parts for the bear the weight of auto body structure, the mechanics characteristic of beams directly determine the auto body's and it is ensured by the beam section shape, but beams'section has the characteristics of complicated shape and most of the beams'section of auto body are changed along the beam. In view of them, the design of pillar sections had been performed by the trial and experiences, this approach is neither reliable nor effective. These problems can be solved by the optimization methods. The optimization is a useful and challenging activity in vehicle structural design. The module of beam section shape optimization of VCD-ICAE may obtain the optimal beam section shape according to the object and constrain defined by user. It may reduce the work intension of designer and help user obtain the satisfactory design scheme.Firstly, this paper illustrates the mainly idea, key technique, mainly function, system test of VCD-ICAE system. Secondly it studies the key technique——1D beam element section shape optimization and elicit the full scale and strongly maneuverability solution. The mainly research content include:1.The brief introduction of VCD-ICAE systemThis system may quickly create parameter concept auto body geometry model and automatically create FE model and boundary condition. It integrates NX Nastran solver that can solves stiffness and modal case. It can automatically create post processing picture and report. It can run HYPER OPT optimization solver to optimize the section shape and thickness of beam and the thickness of sheet panel of concept auto body structure.2.The system test is done for validating the precision of VCD-ICAE. The test program and estimate target is according to the automobile engineering manual——test piece. The result of test is turn up trumps.3.The research for method of optimization of 1D beam element section's shape Firstly, deeply discussing the control method of section shape, it includes five kinds of ways then talks about the advantage and disadvantage for each. Secondly, fetching the formula to calculate the beam section properties such as area, area moment of inertia and torsional constant. Finally, fetching the method of creating beam section's shape according to the beam section properties.4.The 1D beam section's shape optimization base on VCD-ICAE platform Firstly, discussing the process of the 1D beam section's shape optimization based on VCD-ICAE platform. Secondly, Calculating and analyzing the sensitivity value of beam shape and thickness on mass or stiffness. Finally, according to the sensitivity value to optimize the beam section's shape and thickness for getting the optimum auto body structure.The successful development of VCD-ICAE system will accelerate the development process of concept auto body structure, it will reduces the time of development of concept auto body structure and the difficulty of operation.