Impact problems with wildfire2

[KhalidFarouk]

Dear all:


I used to simulate Impact problems with pro/Mechanica motion with wildfire1 using conditional spring and damper. In wildfire2 pro/Mechanica motion is integrated inside the Pro/Mechanism and tell now I could not simulate such problems with the same procedure. Howcan I simulate Impact problems and how can make conditional spring and damper?





Kind regards,

 

[Israr]

pro/Mechanica motion still works with wildfire2 andyoucan do your analysisusing conditional spring and damper.


MDO in Wildfire 2.0 is not mature enough to solve impact and frictional problems. We have to wait for another production release, say WF 3.0 or WF 4.0


Israr

 

[trapper00]

Israr,


So your saying that MDO in Wildfire 2.0 can not solve any impact problems? What about a simple one of dropping a steel ball onto a steel plate?





Thanks


Trapper00

 

[Israr]

It can do that, but there are no contact elements.


israr

 

[trapper00]

Israr,


So in other words, there is no way to bring the "contact" loads into Mechanica?





Thanks


Trapper00

 

[Israr]

contact is in mechanica but not in MDO.


Israr

 

[trapper00]

Israr,


Thanks. You answered my question!!





Trapper00

 

[markthemech]

Pro/Mechanica or MDO will not let you directly analyze impacts with any
certainty. If you do want to analyze the stresses caused by impact
using these tools, you need to do some intial testing of the material
to get some empirical results, which will let you make the CORRECT
assumptions.



Without knowing the duration of the impact or the deflection caused by
the impact, any numbers that you might get out of MDO or Mechanica are
garbage.



Even something as "simple" as a steel ball dropping cannot be simulated accurately using the software alone.



Contact regions in Mechanica are something completely different, since
the parts that are contacting still need to be constrained.



The makers of LS-Dyna offer FEA software that allows you to analyze impacts like this, but even then, garbage in = garbage out.