Optimal Study Of Intergral Body Structure For A Certain Type Of SUV

There are many auto performance parameters, such as reliability, crash safety,NVH, light weight performance. Nowadays crash safety and NVH are becomingmore and more important and become the key factors of automobile brand, andconcerned by the government and customers, thus automakers to devote resources inthese areas.Because crash safety and NVH include the numerous and complex researchcontents, traditional experimental methods are difficult to get ideal studyeffectiveness. Therefore, this paper studies crash safety and NVH by the means ofCAE and Multidisciplinary Design Optimization (MDO). The paper preliminaryanalysis the crash safety and NVH of a certain SUV, then studies the improvement ofSide Impact Safety, pedestrian leg collision Safety and NVH by using approximationmodel agent method and multidisciplinary optimization method. The main researchcontents are：（1）Using approximation model to construct response surface approximationmodel of two subjects namely vehicle side crash safety and lightweight. Amultidisciplinary optimization method based on adaptive weighted is proposed on thebasis of the sequential quadratic programming (SQP). This paper uses this method tooptimize crashworthiness and lightweight of vehicle body. Validation the feasibilityof the optimization result is down, and the test has shown that this method improvedside impact safety of this SUV.（2）By taking the rear door of one SUV as the research object, this paperconducted sensitivity analysis on rear door stiffness (vertical stiffness and lateralstiffness) and the first modal that influences NVH performance, and obtains the keycomponents that affect NVH performance (stiffness and modal of doors). Selectingthe thickness of these key components as design variables, optimization is realized byusing multidisciplinary design module of Hypestudy software, which improves theNVH performance includes stiffness, mode and lightweight of rear door greatly.（3）Analysis of the pedestrian leg collision of this SUV is completed. Firstly, this paper finds the reasons why the injury parameter of leg form excessive whencrashes take place, and proposes improvement for Bumper system structure, and thenapplying the sequential quadratic programming (SQP) to realize Multi-objectivecollaborative optimization of the front vehicle body. The result shows that theoptimization reduces the injury parameter of leg form, and improved pedestrianprotection performance of the vehicle.