Help with Impact Simulation - Hammer Impact

[Anonymous]

Hi everyone, I have a seemingly simple problem but don't know how to go about it. I need to simulate and find the deformation due to a hammer impact on a simple L shape as shown (dimensions 50x50x10mm):

Top end face is constrained while a force is applied to bottom face as shown. The only information I have as of now is that the hammer force or impact load is 50 kg. How would I go about this:

a. Linear static analysis with F = 500 N applied as shown above?

b. Event Simulation where Transient Force = 500 N with an assumed ramp up and ramp down time of 2 milliseconds?

c. Some other method to simulate an impact load or impulse force that I'm missing?

[mohammed.aliTDPXK · Accepted solution]

Hello @Anonymous ,

I would recommend to go with Event Simulation.

--> You can model a hammer head and include in the simulation and provide initial angular velocity.

--> Or use impact load condition for transient load. Time 0 will have 500N magnitude(0,500 and .02, 500 for example) 

Let me know if this helps, Do like the post and accept as solution if this answers your query.

Thanks!

[tonySWCR2]

Impact simulation is not a simple thing. Materials do very interesting things at high speed and load and the simulation has to take this into account, you need a good material model with more than just a static stress/strain curve.

A hammer blow is not a static problem so static simulation isn't going to give you very realistic results. 

I would also be careful when specifying the hammer blow as a force value. Is that peak force and over what time period is the impact? You probably don't know this information, so setting the correct masses/inertias of both parts by ensuring the material models are correct and then giving them the initial velocity of the impact is the right thing to do. If you have a constant force that is applied you can add that too, but most of the effect of a hammer is from its stored energy (kinetic) not the force being applied to it during the impact. 

Explicit analysis is what I would use for this problem. I am not sure on the solver that Fusion uses but judging by the inputs "Event Simulation" is the one you want, as it asks for a small time window so it is probably using an explicit solver.

[mohammed.aliTDPXK]

Hello @tonySWCR2 ,

Yes you are right, event simulation uses explicit solver and I have suggested the same.

Thanks