PSI - Issue 27

Angga Kengkongan Ary et al. / Procedia Structural Integrity 27 (2020) 69–76 Ary et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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Table 1. Chassis design and variation. Design

Material

Thickness

Aluminium 6061 CFRP

0.9 mm 1.4 mm

Fig. 1. Alternative urban vehicle chassis meshing, where: (a), (c), (d), (f) are the structural constraint; (b) is the force applied on z-axis (-150 N); (e) is the force applied on z-axis (-700 N).

In the simulation, the front and rear wheel shaft of the chassis is the supported constraints of the frame and different material properties assigned to the model. It is the aluminum 6061, which widely used in KMHE and CFRP that is used by only a few teams abroad on a similar contest as an innovation to replace the aluminum. Table 2 shown the meshing criteria, and the detail of the material properties used given in Table 3. This simulation completed obtaining the safety factor, stress, displacement, and strain data as the results. Safety factor or factor of safety in engineering define as a ratio of structure’s absolute strength (structural capability) to the actual applied load. It is a measure of the reliability of design manufacture (Matvienko, 2013). Stress obtained by dividing the magnitude P of the load by the cross-sectional area A (McKeen, 2010). A strain defined as the ratio of deformation to length (Yang, 2005). The displacement is the difference between the initial and final position of a point on a structure (Khan, 2013).

Table 2. Mesh criteria. Average Element Size (% of the model size) Solids

Table 3. Material properties (Autodesk Fusion 360). Parameter Al 6061

CFRP 53000

10 No

Shear modulus (MPa) Young’s Modulus (GPa) Density (g/cm 3 ) Yield strength (MPa) Tensile strength (MPa) Poisson’s ratio ( -)

25864

Scale Mesh Size Part

68.9 2.7 275 310 0.33

133 1.43 300 577 0.39

Average Element Size (absolute value)

-

Element Order

Parabolic

Create Curved Mesh Elements Max. Turn Angle on Curves (Deg.) Max. Adjacent Mesh Size Ratio

No 60 1.5 10 20

Max. Aspect Ratio

Minimum Element Size (% of average size)

4. Results and discussion The alternative urban vehicle chassis design was modeled and simulated using different materials, different loads, and different thicknesses to produce reference data to develop car chassis. The obtained results are physical behavior of the frame after the defined parameters are applied, i.e., the value of minimum safety factor, maximum stress,