Finite Element Simulation Analysis Of The Rear Seat For Automobile

As an important part of automotive interior systems and occupant restraint systems, carseats connect the car body and occupants directly and play an important role in protectingthe occupants in the car collision. At the same time, its ride comfort cannot be ignored. Mostof countries around the world have a strict requirement on the car seat features, includingboth static and dynamic characteristics. Static characteristic mainly refers to the strength andstiffness characteristics when car seats subject to limit static load. While, Dynamiccharacteristic mainly refers to the strength and stiffness characteristics when performing sledcrash test, etc. After the turn of the twenty-first century, as the most widely used and aconsiderably mature method in CAE, Finite Element Method has also been widely used inthe analysis and design process of the car seat structure. In addition, according to actualconditions in China, car rear seats are even more important, therefore, CAE technology arerequired at the design stage of the car seats, it could provide a reference for further design.Under these circumstances, this essay writes about the finite element simulationanalysis of a special form of automobile rear seat combining an actual program about thefinite element simulation analysis of car rear seat. The finite element model of the structureof the metal frame of the seat is built by finite element pre-processing software HyperMesh;After analyzing relevant provisions on car seat static strength of various countries andenterprise, nonlinear static finite element solver ABAQUS/Standard is selected to conductthe simulation analysis of static strength, by simulating various loading methods,investigating the distribution of stress and displacement, loading method which is suitablefor the special form of seat structure is determined; FEA solver Ls-Dyna for solving thecollision and impact of the problem is selected to analyze the simulation of sled impact test,it is verified that the structure meets the requirements of the relevant regulations andstandards or not; Radioss BulkData solver is selected to calculate the modal frequency of thefirst six real-number order, vibration characteristics of the structure is evaluated. This thesisincludes five chapters, its main contents respectively are:In chapter1, the structure, classification and function of the car seat is presented in detail, in particular, a detailed analysis of the structure of seat metal frame is performed,which has a great influence on the passive safety. Through the introduction of domestic andforeign research present situation, the main content and significance of this thesis iselaborated.In chapter2, on the basis of analysis about the seat structure which is studied in thispaper, considering about the principles of the finite element model simplification, process ofbuilding the finite element model of the seat structure analysis in this paper is introduce indetail, including element types, material and physical attributes and boundary conditions etc.In chapter3, according to the provisions of relevant and standards relating to seat staticstrength of enterprises and various countries, three standards which could apply to theanalysis of the seat structure static characteristics in this thesis are selected, including theseat assembly static strength, the seatback static strength, the static strength of the headrest.In the process of the seat assembly static strength analysis, two loading methods are chosen.By comparison of the results, a suitable loading method of this structure is selected. Usingthis loading method, analysis of the seatback static strength, the displacement and staticstrength of the headrest is performed. It is verified that the structure meets the requirementsof the relevant regulations and standards or not.In chapter4, Regulations about sled impact test and the sensitive frequency of human’sbody are introduced. Furthermore, the process of establishing the finite element model whichis used to Ls-Dyna solver is explained in detail, including converting of element types,definition of materials and properties, constraint and load settings, settings of calculation andcontrol parameters. It is verified that the structure meets the requirements of the relevantregulations and standards or not. But it should be noted that the stress of a part of thestructure is a little larger. The modal frequency of the first six real-number order is calculated,it could be concluded that the vibration characteristics of the structure is preferably.In chapter5, a conclusion of this thesis is made and the further research content isillustrated.