Impact Dynamics
Impact Dynamics
(OP)
Dear All
I hope you are fine and in best of health. I have started working on impact analysis and staright away some questions. I am using the same geometry that i used for contact analysis, the axisymmetric model using axisymetric elements.
Now what I am doing is that I have changed the analysis to dynamic explicit and instead of displacement i have given a initial velocity with the poin mass to the analytical rigid part. It works fine but But i want to see the impactor to impact the thick plate and than bounce normally as it happens in the real time.Do I assign gravity to the impactor or whats the slotion.
I want to see the force Vs indentation of this impact. I know you said I have to use different thread. I will make a new thread and post this on that too. Please helpBest regards
I hope you are fine and in best of health. I have started working on impact analysis and staright away some questions. I am using the same geometry that i used for contact analysis, the axisymmetric model using axisymetric elements.
Now what I am doing is that I have changed the analysis to dynamic explicit and instead of displacement i have given a initial velocity with the poin mass to the analytical rigid part. It works fine but But i want to see the impactor to impact the thick plate and than bounce normally as it happens in the real time.Do I assign gravity to the impactor or whats the slotion.
I want to see the force Vs indentation of this impact. I know you said I have to use different thread. I will make a new thread and post this on that too. Please helpBest regards





RE: Impact Dynamics
Rob Stupplebeen
RE: Impact Dynamics
RE: Impact Dynamics
Thanks for your valuable suggestions, I really appreciate it. I have run the case with your suggestions, but there is a problem. When I assign the gravity load to the analytical rigid reference point, it does not recognise it and gives an error unknown assembly to reference punch.
I have attached the CAE file for you to look at and you can run the job named impac2 to see the results.
Please tell me how do i eradicate this problem and where exactly i give the gravity on the analytical rigid part.
Best regards
RE: Impact Dynamics
2. Nlgeom: On
3. Apply an inertia to your reference point. I think this is what you did though. I would try redefining the inertia possibly not in a set.
I hope this helps.
Rob Stupplebeen
RE: Impact Dynamics
Thanks alot for the useful tips. I have tried they way you suggested but i dont seem to get the gravity where i want. As you say I need to apply gravity, so i try to apply in on the reference point of the analytical rigid part but it does not work, it gives me an error
[DLOAD, file "impac2.inp", line 10284: Unknown assembly element set REFPUNCH
Error in job impac2: ELEMENT SET ASSEMBLY_REFPUNCH HAS NOT BEEN DEFINED]
What shall i do, where shall i apply the gravity load.
Also the mass of the impactor is 0.5 kg and I have applied to the reference point of impactor.
Best regards