Learning Forum

[zabee.k]

Hello,

I did a drop test analysis using workbench Ls Dyna on an object and i have noticed that the acceleration on the object is very large. Can someone please explain why we are getting such huge acceleration and whats the physics behind this. What i should be doing to get the proper acceleration values.

Please find the attached images for reference.

Thanks,

[Armin]

Hi Zabee,

In explicit dynamics analyses, such as the drop test you performed, stress waves travel through the model upon impact and may interact and amplify each other. This explains why acceleration is locally high at the element level where such interactions occur.

[zabee.k]

so it is normal to have to these high acceleration? 

[Armin]

It depends on the drop height, material, and other factors, but locally high acceleration magnitudes in drop tests are normal in my opinion. You can also check the values reported under the "Average" column to see if they are better in line with your expectation.