DUT - Impact Absorption Device
ANSYS Explicit STR utilises the solver capabilities of the explicit solver, AUTODYN combined with the pre-processing power and intuitive interface of ANSYS Workbench. Explicit time integration is more accurate and efficient for simulations involving shock wave propagation, large deformations and strains, non-linear material behaviour, complex contact, fragmentation as well as non-linear buckling. Typical applications include drop tests, impact analysis and penetration.
In this study, Qfinsoft utilised ANSYS Explicit STR to simulate the behaviour of an impact absorbing device during a collision. The model consists of an outer casing surrounding a flexible membrane filled with a granular media. The model is set up to replicate a cylindrical shaft impacting the outer casing for a range of initial velocities.
Figure 1: Computational mesh generated for the explicit dynamic simulation
Figure 2: Impact velocity tracer during collision
An array of velocities is simulated to establish any relationships that might exist with regard to energies and erosion rates. Reaction forces are extracted at the back surface of the casing as well as energies and velocities to determine how effective the device is in absorbing the impact.
Figure 3: Deformation of the system in the Z direction
Figure 4: Equivalent elastic strain of the flexible membrane