Parametric study on a frontal car crash simulation using explicit dynamics module of Ansys

OBJECTIVE

To perform a parametric study on a frontal car crash simulation using 3 different values of thickness for the car body.

Importing the CAD model

The CAD model is imported using spaceclaim and checked for any geometry errors.

Simulation setup

Material Assignment

The wall is given material structural steel with rigid stiffness behaviour.

The car body is assigned with material stainless steel NL 2 with flexible stiffness behaviour. Body interactions for all bodies are set to frictionless.

Thickness of the Car-body

The car body thickness value is defined as 0.3mm and the thickness tab is marked as a parametric value. Two other thickness values 0.5 mm and 0.7mm are given as two design points.

And in the output results, the requested parametric results are given out for these three thickness values

Symmerty region definition

To reduce computational power requirements only half of the car body is simulated. Hence two symmetry regions are defined, one for the rigid wall and another for the car body.

Mesh Generation

The car body and wall are meshed with default mesh. Insteas of default mesh, tetrahedrons method can be also used.

Analysis settings

The simulation is run with a step end time of 1e-003 seconds

The step controls and solver controls are as given below

The back end of the car is fixed and the wall is moved into the car for a distance of 500 mm.

Results

Total Deformation

Equivalent Stress

Parametric study

For three values of car-body thickness total deformation and eauivalent stress values are obtained.

Car body thickness	Maximum Total deformation	Maximum Equivalent Elastic Stress
0.3 mm	1039.3 mm	3063.8 Mpa
0.5 mm	1035.43 mm	2708.8 MPa
0.7 mm	1031.94 mm	2657.6 MPa

It is observed that as thickness value increases the resistance offered increases thus resulting in decreased total deformation value.

X axis - thickness for the car body

Y axis - maximum total deformation

As the thickness increases the stress induced also decreases.

Ansys file link

https://drive.google.com/file/d/1RTiQwdzZVpc74QJBHGCd-P0ujPBySWMm/view?usp=sharing