FINAL YEAR PROJECT DEPARTMENT OF MECHANICAL ENGINEERING A.V.C COLLEGE OF ENGINEERING :

2 CRASH ANALYSIS OF S-RAIL ASSEMBLY IN AUTOMOBILES

3 PROJECT GUIDE : INTERNAL GUIDE: Mr. A.BALAJI, M.E., LECTURER IN MECHANICAL DEPARTMENT A.V.C COLLEGE OF ENGINEERING. EXTERNAL GUIDE: Mr. A.BALAJI, M.Tech., PROJECT MANAGER CHETROIT TECHNOLOGIES. PROJECT STUDENTS : A.SUDHAN S.SELVAMUTHUKUMARAN N.VIMALBARATH R.VINOTHKUMAR

4 FLOW OF PRESENTATION ► COMPANY PROFILE ► ABSTRACT ► PROBLEMS ► OBJECTIVES ► SOFTWARE USED ► METHODOLOGY ► APPLICATIONS ► FUTURE SCOPE OF THE PROJECT ► CONCLUSION ► REFERENCE

COMPANY PROFILE COMPANY PROFILE CHETROIT Technologies is one of the fastest growing company providing engineering solutions using innovative engineering applications. We provide end- to-end solutions from conceptualization, engineering design and analysis. Our expertise in diverse engineering applications influences the customers to attain their objectives beyond their expectations with high quality services. We also focus in Training & Development in CAD/CAM/CAE, intensive industrial oriented training according to current requirements with project experience & design concepts for corporate and engineering students. 5

ABSTRACT  S-rails in vehicle structure are the main energy- absorbing components in case of frontal collision. Optimal crashworthiness design of such components is one of the crucial tasks in designing crashworthy vehicles.  In this paper, an S-Rail impact model is extracted from a true rail used in a vehicle frame. Response surface method coupled with genetic algorithm is presented and utilized to obtain optimal crashworthiness design.  The method adopted in this research makes use of design of experiments (DOE) and numerical optimization algorithms. 6

 The nonlinear explicit finite element code PAM- CRASH was used to conduct the rail impact problems and generate the energy functions to be maximized.  Several design parameters like the cross section width, cross section height and the curvature angle have been proposed and used to optimize the S-railpsilas structure.  The results indicated the promising capabilities of the proposed optimal design method for the energy-absorbing of S-rails. 7

REASON FOR CHOOSING THE PROJECT ► ► During collision shock is transferred to whole body of the automobile structure. ► ► In conventional S-rail, it can not absorb more energy. ► ► More impact will affect the passenger. ► ► It leads to failure and loss of life of the passenger

OBJECTIVES ► ► To reduce the shock impact transferred to whole body of the automobile structure. ► ► By using modified S-rail, kinetic energy is absorbed in front of the body of automobile during accident. ► ► To save the life of the passenger who are in the automobile.

10 SOFTWRAE USED ► CATIA V5 – Modeling purpose. ► HYPERMESH – Meshing purpose. ► ABAQUS – Running the project and result viewing.

THE AUTOMOBILE STRUCTURE S-RAIL

S-RAIL ASSEMBLY

S-RAIL DEFINITION S-Rail assembly is a vehicle structure that can absorb the crash energy by controlled vehicle deformations while maintaining adequate space so that residual crash energy can be managed by the restraint systems to minimize crash loads transfer to the vehicle occupants. S-Rail assembly is a vehicle structure that can absorb the crash energy by controlled vehicle deformations while maintaining adequate space so that residual crash energy can be managed by the restraint systems to minimize crash loads transfer to the vehicle occupants. 13

Introduction of crush Initiators ► The existing design for S-Rail assembly plays an important role in absorbing the impact during a crash. But there is always a need for improvement. The makers are constantly looking for more efficient and better design which reaps more results with less change in the existing design. ► For the existing design of S-Rail assembly, the kinetic energy during a crash is absorbed when the bending of the S-Rail occurs. Here, we are introducing a few crush initiators, whish initiate the axial crushing or collapse of the front part of the S-Rail assembly, when it collides with an obstacle. The part where the axial collapse occurs is known as the ‘Crash zone’. In an S-Rail assembly, the axial collapse occurs till the crash zone ends and the usual bending occurs afterwards. In this new design of S-Rail assembly, energy is absorbed by the both axial collapse and bending. This improves the efficiency of the S-Rail assembly in the absorption of the kinetic energy, during a crash. 14

SIDE AND FRONT VIEW OF S-RAIL ASSEMBLY WITH OUT CRUSH INITIATORS 15

16 SIDE AND FRONT VIEW OF S-RAIL ASSEMBLY WITH CRUSH INITIATORS

17METHODOLOGY MODELING USING CATIA V5 MESHING USING HYPERMESH RUN & RESULT VIEWING USING ABAQUS PREPROCESSING PROCESSING POST PROCESSING

Preprocessing In this project we are meshing the S-Rail assembly in HyperMesh in Altair hypermesh 8.0. Abaqus elements are used in the HyperMesh. The CATIA model, saved in IGES file format, is imported to HyperMesh. After improving, the mid-surface is selected from the ‘geometry’ page and the ‘extract command is given after selecting the component to be meshed. After this the 2D page is selected and ’automesh’ is given. Here shell meshing is done and the element size is given. Then the meshed component is then saved with INP extension.

Solving and post processing: In this project, we are doing the solving and post processing work ABAQUS version 6.5 software. The component is imported to ABAQUS. The material properties such as young’s modules, yield strength, etc is given in ‘property’ module. After this, the ‘assembly’ module is selected and the parts, which are to be solved, are selected. Following this, the ‘step’ module is selected and the dynamic, explicit method is selected for solving the job. The boundary conditions and initial parameters are given in the ‘load’ module. After this the job module is selected and the, to be solved, is submitted for solving. The simulation is done in the ‘visualization’ module and it is saved in a video format.

20 CATIA model of front S-Rail assembly without crush initiators MODELLING FILE

21 CATIA model of front S-Rail assembly with crush initiators

22 CATIA model of the Barrier

23 MATERIAL PROPERTIES Linear Material properties : Young’s modulus = MPa Poisson's ratio = 0.3 Non Linear Material properties :

24 No of elements : 656 Type of element : S3R, S4R Deformable elements Element size : 30mm FEM model – S-rail without crush initiators

25 FEM model – S-rail with crush initiators No of elements : 1922 Type of element : S3R, S4R Deformable elements Element size : min 10 max 30mm

26 FEM model – Barrier No of elements : 35 Type of element : R3D4, R3D3 Rigid elements Element size : 30mm

27 Boundary conditions All degrees of freedom arrested Edge nodes are given 30KMPH velocity in the crash direction. Same nodes are arrested in translations in other direction.

28 Deformation video of S-rail without crush initiators

29 Deformation video of S-rail with crush initiators

30 Von misses stress plot without crush initiators Before CrashAfter Crash

31 Von misses stress plot with crush initiators Before CrashAfter Crash

32 time step (sec) Reaction forces in crash direction (-y direction) (Newton) without crash initiatiors with crash initiators Reaction forces table

33GRAPH F O R C E (N) DISTANCE(MM) SERIES 1 – WITHOUT CRUSH INITIATORS SERIES 2 – WITH CRUSH INITIATORS

34 APPLICATIONS ► ► It is used in variety of small segment and medium segment luxury cars, like Ambassador, Maruti 800, Toyota Qualis, TATA Sumo, etc.,

35 FUTURE SCOPE OF THE PROJECT ► Here after all the vehicles are equipped with this protecting techniques. ► Most of the researches are going on in the field of crush Initiators in order to determine how many initiators are best. how many initiators are best. ► Even it can be applied to all the heavy vehicles in future.

36 RESULT AND DISCUSSION  As we have seen so far the front S-Rail assembly of vehicle is used to absorb energy and maintain survival space for the occupants during a collision.  The existing design of the S-Rail assembly makes it possible to absorb energy during a crash by bending. In our project, we have introduce CRUSH INITIATORS to the front part of the existing s-rail assembly design which absorbs energy in addition to the energy absorbed by the bending action, due to the axial collapse.

37  The S-rail was first modeled in CATIA software. Then the CATIA model was imported to hyper mesh soft ware as an IGES file and was subjected to meshing. The meshed S-rail model was then exported to ABAQUS software where the solving and post- processing was done and the simulation was carried out.  From the study that we carried out and from the theoretical analysis we have come to conclusion that the energy absorbed during the collision by the front S-rail assembly with crush initiators is more than the energy absorbed by the front S-rail assembly without crush initiators

38REFERENCE ► American Iron and Steel Institute “Vehicle Crashworthiness and Occupant Protection”. ► CADDAM Technologies “CATIA Training Guide”; Edition 2008 ► CADDAM Technologies “CATIA Training Guide”; Edition 2008 ► Research Council for Automobile Repair “Vehicle Design Features For Optimum Low Speed Impact Performance”; Edition, January 1995 ► Research Council for Automobile Repair “Vehicle Design Features For Optimum Low Speed Impact Performance”; Edition, January 1995 ► The Tracy Firm Attorneys At Law “vehicle Crashworthiness- identifying If Vehicle Safety Defects Exists”. ► The Tracy Firm Attorneys At Law “vehicle Crashworthiness- identifying If Vehicle Safety Defects Exists”. WEB ADDRESS:

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