Modeling Of Concept Vehicle And Optimization For Cross-section Size

Energy crisis coupled with environmental pollution propelled the traditional automobile enterprises to rack their brains to reduce emissions and to improve fuel efficiency. The electric vehicles can not be accepted by the mass customers in a short period of time for long charging time and short endurance mileage. Automotive lightweight technology, to a certain extent, can alleviate the above problems. As an important subject, it has been fully focused by people in this industry. During the detailed body design stage, the model data tends to reach perfect, this caused great resistance to the implementation of the lightweight project and increase of cost. Compared with detailed design stage, the model data has not been completed in conceptual design phase, there is a great potential in losing weight and the lowering implementation cost. By establishing a simple model, then based on this model to implementing cross-section optimization in early stage, not only can reduce costs also can promote weight loss potential.The conceptual model of bending and torsion stiffness of the new models are build by virtue of the data of the same familial vehicle body and based on the beam elements with the detailed joints, during the early automobile design stage. In the process of modeling, four kinds of model s approaches the coupling of the beam and the joint, the choosing of the section form, the handling and loading of the solder, constraint node, which have obvious effect on the results have been studied. Many kinds of processing modes have been contrastively analyzed through the adoption of the simple modeling test technique to choose the best modeling scheme. By comparing the conceptual and detailed model based on the bending and torsion properties stiffness, using the overall property errors and the errors with different beam sizes to verify the reliability.The simple beam element model establishment and the verification in early stage have paved the way for the later cross-section size optimization. The PBMSECT parameter optimization technique is proposed for any geometrical shapes without the third party optimization software. The thesis introduced the parameterized method of any section beam in detail and demonstrated the application method and the reliability of the optimized results by giving the examples of simple cantilever beam. Based on conceptual model, the method of artificial screening was adopted after the sensitivity analyses to remove some segments that obviously have great effect on other properties and determine the final section to be optimized. The application for the optimization methods of parameters of any sections to the whole body at the early design stage can realize the lightweight goal at the early design stage.