Collision, Impact Testing, Drop Weight Test

[TyBarker]

I am trying to drop a weight onto a beam.... I have tried the regular program, but I am having issues with defining a contact element that works with solid 185 (Trying to use Mass21, Conta173, and Targe170) and having an impact (txt file attached).

I switched over to WB to try to solve some of these issues, but ironically I am having more trouble. I modeled my beam and a cylinder to act as the drop weight (spaced for the desired drop height), and moved into simulation with giving the appropriate material parameters and changing density to achieve the right weight. I then tried to apply an acceleration to the system (trying to use gravity for an actual drop rather than apply a point load), but my results are nonsensical.

If I do not define a contact region or define a spring connection then my cylinder goes straight through my beam without any resistance. I tried a general and planar connection, but then the cylinder fails to move and only gravity is applied. If anyone has experience with colliding bodies, any assistance would be greatly appreciated.

Thanks!

 

[slumdogengineer]

I can't offer any exact help, but if your simulation involves contact and is dynamic (not static or quasi-static), using an explicit solver is a much better approach, for example LS-Dyna (if you have the licence for this). In my experience contact technology in the implicit solver in Ansys is a bit unreliable.

 

[Howiedoin]

Although one can use explicit dynamics, this problem is readily solved by using transient dynamics using the classic interface. Just follow the method explained in ANSYS section 5.3 (Performing a Full Transient Dynamic Analysis) of the help file.
Such a problem can be broken into 2 parts: solving for the initial velocity at the point of contact via static analysis with time integration off and then solving the next case with time integration "on". The following link has this documentation:

http://uic.edu/depts/accc/software/ansys/html/guide_55/g-str/GSTR5.htm