Dynamic Explicit analysis in cantilever beam 2

[Mechanicslearner]

Hello,

I applied point load of 30 Newtons close to the tip of cantilever beam of thickness 4 mm fixed at other end. I run the analysis using dynamic explicit with step time of 1 second. After the analysis when I run the time history the beam is swinging ( it deflects on the load direction and start swinging up after some frame rate) . I try to do in dynamic just to see the reality bending because in static if you keep on increasing load after some point it stretches. My question is why it is swinging ? is it because of elasticity? or the load is applied at one frame (0.05 sec) and load is removed at another frame (0.05 sec or even later) ?
Because in reality when you put load (hanging load) at the tip of cantilever beam it just stays there in bending state and it wont swing upto to its original state eventhough if there is little spring back

Can someone please help me with this?

 

[IceBreakerSours]

There are so many gaps in your *basic* understanding - all the way from the mathematical to the mechanics side of things. Go back to Newton's laws, swinging pendulum, natural frequencies, F = mx'' + bx' + cx etc.

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[Mechanicslearner]

Hello,

Thanks for the reply. I know how Newton's law, frequencies and pendulum works.Sorry for asking silly questions because am still learning abaqus. Just now found out the default load is not in ramp its in instantaneous.

 

[Mustaine3]

because in static if you keep on increasing load after some point it stretches.

Only if you run it linear. Activate NLGEOM and decide if the load shall rotate with the beam tip or not.

 

[IceBreakerSours]

a) The beam will act like a tuning fork when it is hit with an instantaneous load - which is precisely what you are observing.
b) You do NOT need the explicit numerical scheme to run this problem. You can easily do this in Static (as suggested by Mustaine3) or Dynamic, Implicit.

I recommend going through the Getting Started guide.

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[Mechanicslearner]

hello,

I know I can achieve in static too which is simpler method as I said before in abaqus when you keep on increasing load in the visualization it starts stretching instead of bending further so I used explicit just to see the bending. I tried static, explicit and implicit and found static and implicit give exact same results whereas explicit gives close to real result. Does Implicit is also good for wind pressure load?