Gravity with rigid body
Gravity with rigid body
(OP)
Hello all,
My model consists of three parts: impactor, plate and supports. On the supports the plate is located and the impactor is dropped at great speed. The object of the study is to determine the stress, energy released in the impact... with this objective, I have thought that it could define the impactor and the supports like rigid solids using (Discrete Rigid or Analytical Rigid) but when attempt to define the gravity acting on the complete model, if attempt to apply the gravity on the node of reference of the impactor, Abaqus not permite it.
(Module --> Load -->-Create --> Gravity-->....)
How I can define the gravity acting on the set? . When I define the gravity in a deformable solid is no problem. Why yes in the case of rigid solids? There is something is not doing well?
Please, help me.
My model consists of three parts: impactor, plate and supports. On the supports the plate is located and the impactor is dropped at great speed. The object of the study is to determine the stress, energy released in the impact... with this objective, I have thought that it could define the impactor and the supports like rigid solids using (Discrete Rigid or Analytical Rigid) but when attempt to define the gravity acting on the complete model, if attempt to apply the gravity on the node of reference of the impactor, Abaqus not permite it.
(Module --> Load -->-Create --> Gravity-->....)
How I can define the gravity acting on the set? . When I define the gravity in a deformable solid is no problem. Why yes in the case of rigid solids? There is something is not doing well?
Please, help me.





RE: Gravity with rigid body
Regards
RE: Gravity with rigid body
So the model seems to keep the same deformation doesn’t matter witch mass you give to the impactor (please confirm if I well understand).
You must give more details: kind of analysis (standard or explicit), BC (speed field or displacement amplitude).
Regards
RE: Gravity with rigid body
I am working with Abaqus/explicit.
I define the speed of the impactor in the reference node and restrict in this node all the displacements (except the vertical) and rotary.
My problem is that I do not know what option I must use when I am in Step --> Manager --> Edit --> Mass scaling.. in mass sacling appears two options:
1)scaled mass and "throughout step" definitions from the previous step.
2)Use scaling definition below...(and options appears such as semi-automatic, automatic..)
what I must use? What I want is to see as it affects the change of mass in the impactor to the deformation and stress of the plate on which impactor saying hits.
please, help me gelu,
thanks in advance
RE: Gravity with rigid body
Step/mass scaling/use scaling definitions below/semi-automatic mass scaling/whole model (or better put only the plate like this is no doubt)/at the beginning of step/scale to target time (put a value like 5.E-6 and adjust after depending on calculation time)/live all other option to default values.
Run the job interactively, look to mass scale factor and adjust in next run the mass of the impactor with the same factor (normally you will need to increase the mass).
To have an accurate solution I think will be necessary to change the way you apply the kinematics (change for an amplitude displacement for the same amount of kinetic energy and like this the mass point become unnecessary) or change the rigid impactor for a deformable body and include them in mass scaling process.
Success
RE: Gravity with rigid body
I am going to prove what you say to me and to you I will maintain informed into the advances
Bye!!
RE: Gravity with rigid body
Charley
RE: Gravity with rigid body
if I apply the gravity like a concentrated force, Can at the same time define the initial speed of the impactor and this force?
Regards, Irene
RE: Gravity with rigid body
RE: Gravity with rigid body
Hello Charlesbreen,
> When I define the gravity like a force concentrated in the reference node, it continues happening the same, independently if I apply a force of 58Newton or if it is of 200Newton etc.. the plate becomes deformed the same amount thing that I know that it is not possible then to greater load, greater must be the deformation What is happening?
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