DESIGN & STRUCTURAL PERFORMANCE ANALYSIS OF SUPRA SAE CAR CHASSIS

DESIGN & STRUCTURAL PERFORMANCE ANALYSIS OF SUPRA SAE CAR CHASSISPREPARED BY: under the guidance of:Prashant sahgal Er. Ramendra singh niranjanB.Tech (4rth Year)h.o.d(Mechanical Engineering) dept. of mechanical engineering u.i.e.t c.s.j.m university Kanpur

DESIGN OBJECTIVESResearch fundamentals behind designing a space frame that will see forces associated with a race car (COMPLETED).

Research chassis materials that can withstand the high performance ratings of a formula style race car (COMPLETED).

Design a chassis that will be able to withstand the loads from static forces using solid modeling software.

Perform static load analysis using finite element analysis software.

COMPUTER AIDED ENGINEERINGCATIA & ANSYSComputer-aided engineering (CAE) is the broad usage of computer software to aid in engineering analysis tasks. It includes Finite Element Analysis (FEA), Computational Fluid Dynamics (CFD), Multibody dynamics (MBD), and optimization.

CATIA (Computer Aided Three-dimensional Interactive Application) is a multi-platform CAD/CAM/CAE commercial software suite developed by the French company Dassault Systmes. Written in the C++ programming language.

ANSYS Mechanical software is a comprehensive FEA analysis (finite element) tool for structural analysis, including linear, nonlinear and dynamic studies. The engineering simulation product provides a complete set of elements behavior, material models and equation solvers for a wide range of mechanical design problems.

CAE IN AUTOMOTIVE INDUSTRYCAE tools are very widely used in theautomotive industry.

Reduce product development cost and time.

Improving the safety, comfort, and durability of the vehicles.

Design verification is now done using computer simulations rather than physicalprototypetesting.

Audi R8 is designed on CATIA V5.

Several MNCs like BMW, Mercedes Benz, TATA Motors, Mahindra & Mahindra also uses these CAE software (CATIA specially).

FRAME NOMENCLATUREMain Roll Hoop

Front Hoop Bracing

Front Bulk head

Front bulkhead Support

Front Roll Hoop

Main Hoop BracingSide Impact Structure

BASIC RULES FOR FRAME APPROVALTo get a frame approved at Technical Inspection:

Minimum tube size, 1.00inch OD x 0.049 inch wall (25.0 mm x 1.2 mm metric)

Triangulation

No bent tubes (other than Main Hoop and Front Hoop)

Loads from Mandated Tubes go to Structural Nodes.

DESIGN PROCESSBasic Hand Sketching Sketch Drafting on Chart Paper Modelling in CATIA V5 Finite Element Modelling in ANSYS 14.5 Analyzing the Model in ANSYS 14.5 Optimize the Model according to the results obtained Re-modelling of the Improved model in CATIA V5 Drafting the Improved Model

GENERAL REQUIREMENTSMain & Front Roll Hoop

Main Hoop Bracing

Frontal Impact Structure

Bulkhead

Side Impact Structure

Cockpit

Mesh Element Pipe 289Element Size 10mmQuality High Number of Elements 5573Number of Nodes 11073

FRONT ANALYSISA vehicle moving with a velocity of 100kmph (27.78m/s) and rams into the stationary mass longitudinally. (WORST CASE)

According to research, impact time is taken 0.15 seconds.

Mass of the Vehicle is taken approximately 300kg.

Load of 55560N corresponding to the deceleration value of 18.52g acting longitudinally on the front bulkhead of the frame at two keypoints.

Maximum Deformation is 0.91437mm.Von Mises stress is 113.206MPa.The Factor of Safety is 3.84

SIDE IMPACT

The vehicle gets hit from one side of the frame

The deceleration value for side impact is 3g (9000N approx.)

Fixing lower points of the front suspension in all the directions

Fixing lower rear suspension points in all the directions

Maximum deformation is 4.98647mm.Von Mises Stress recorded is 287.802MPa.The factor of safety for the frame is 1.51

TORSIONAL ANALYSISThe vehicle traverses on an uneven road.

The two tyres on the front axle experience a moment.

NO CONSTRAINT at the front suspension points.

Fixed all rear suspension points in all directions.

Load of equal magnitude 3g (9000N) but opposite in direction is applied on front suspension points.

deformation of 4.59129mm.Von Mises Stress is recorded as 259.805MPa.factor of safety for the frame is 1.67

BUMP ANALYSISThe suspension system are compressed to its maximum extent and act like solid member of the vehicle.

Load is transferred to the roll cage members of the vehicle.

NO CONSTRAINTS on the front suspension points.

Vertically upward load of magnitude 3g (9000N approx.) at 8 nodes of the front suspension points in the frame.

The deformation of 4.82954mm.Von Mises Stress is recorded as 220.641 MPa.Factor of Safety for the frame is 1.97

ROLL OVER ANALYSISThe vehicle topples down from a slope with an angle of 45.

The upper and rear members of the vehicle will bear the force.

Load of magnitude 3g (9000N approx.) at the 4 nodes is applied inclined at an angle of 45.

Fix front suspension points(lower) in y-direction only.

Fix rear suspension points (lower) in all direction

Deformation is 1.0922mm.Von Mises Stress is recorded as 73.9179MPa.Factor of Safety for the frame is 5.88

RESULTS & CONCLUSIONStress plots and deformations of critical elements undergoing different loads during the tests were analyzed using ANSYS.

The use of finite element analysis was invaluable to the design and analysis of the frame for SUPRA SAE FORMULA ONE vehicle. In future work on this project we could perform and demonstrate the Dynamic Analysis by using CAE software called LS-DYNA.Fabrication of the model.

Type Of Impact TestLoading Force (N)Number Of NodesMaximum Deformation(mm)Von Mises Stress(MPa)Factor Of SafetyFront 5556020.91437113.213.84Side 900034.98647287.801.51Torsional900084.59129259.801.67Bump900084.82954220.641.97Roll Over900041.012273.925.88