Week-7 Head Impact

Report Week 7 Head Impact

Aim: simulate 3 cases below and complete analysis:

1. The impact simulation of a simple head impact with the Rigid wall.
2. The impact simulation of the Headform provided with the Rigid wall with the Stress / Strain plots and acceleration plot.
3. The impact simulation of the head form with the Hood with the Stress / Strain plots and acceleration plot. For the hood, you can use Aluminium.
4. The Stress / Strain plot from the Rigidwall simulation should be compared with the Stress / Strain plot from the Hood Simulation and there should be a detailed explanation if there is any difference in the plots.

Procudure:

Case 1: The impact simulation of a simple head impact with the Rigid wall.

Import case 1 meshed part:

Create material:

Create section:

Assign material and section to part:

Initial velocity: 40KM/H=11.1MM/MS

Rigid wall:

Contact: self contact

Control:

Termination: 5ms

Database: ASCII Option choose GLSAT, NODOUT and RWFORC with 0.5 DT.

Save the case, run simulation.

Case 2: The impact simulation of the Headform provided with the Rigid wall

Import mesh part:

Create a new Ls Dyna file and create following keywords:

These will include part to the new file and rotate 50 degree along Y axis

Initial velocity: 40KM/H=11.1MM/MM, which is 7.14 MM/MS in x axis and 8.51MM/MS in Z axis

Rigid wall:

Contact:

Self contact:

Surface to surface contact

Control:

Termination:

Database: ASCII Option choose GLSAT, NODOUT and RWFORC with 0.5 DT.

Save the main case, run simulation.

Case 3: The impact simulation of the head form with the Hood

Open meshed hood file:

Create include and define transform keywords:

Reopen the file, you can see headform is with hood and rotate 50 degree along Y axis

Create material for hood:

Create section for hood:

Assign material and section:

Boundary condition: the edge of hood is fixed in 6 degree of freedom:

Initial velocity:

Contact:

Control:

Database: ASCII Option choose GLSAT, NODOUT and RWFORC with 1 DT.

Save the main case, run simulation.

Result:

1. Stress:

case 1:

case 2:

case 3:

2. Strain:

case 1:

case 2:

case 3:

3. HIC analysis

case 1:

case 2:

case 3:

HIC in case 1 and case 2 are very high because they hit the rigid wall. However HIC in case 3 is 381 which is less than safe value becasue alumimun absorb the energy.

Conclusion:

In this report, 3 cases are simulated in different situation. "Include" is a efficient key word to combine different model. Stress and strain plot are displayed. HIC plots are displayed and analysis is completed. More detailed animation can be watched in uploaded keywords document. Case 1 and case 2 are attached, but case 3 is too large, it is over 100MB, I have sent it by email.