Learning Forum

[deepesh.p.gurdasani]

Hello, 

Is there any way to scope acceleration to a 'Point mass' ?

If scoping not possible directly, any other method can you suggest ?

Thanks in advance

[peteroznewman]

Which analysis are you asking about, Static Structural or Transient Structural or some other type?

[deepesh.p.gurdasani]

[deepesh.p.gurdasani]

Static Structural..

[peteroznewman]

In a Static Structural model in Mechanical on the Environment tab, there is an Inertial load category that allows you to add an Acceleration load which will act on all the mass in the model including the Point Mass.

If you only want the acceleration to act on the point mass and not the structure supporting the point mass, set the density of the structure material to a value of 0.

[deepesh.p.gurdasani]

Thanks for the reply.

Setting tbe density of whole structure in engineering data to 0 you mean to say?

Is there any specific reason behind it that we are setting density as 0 for acceleration act on point mass?

Thanks in advance.

[peteroznewman]

If you want the acceleration forces to act on the entire structure and the point mass, then you just add the acceleration load.  This is typically what is done.

If you have no reason to exclude the acceleration forces on the structure, then you don't set the density to 0 in Engineering Data.

 

[deepesh.p.gurdasani]

What I meant to ask was

1) why are we setting density to 0 for acceleration to get applied on 'Point mass' ?

2) Also, when we set density to 0, wouldn't this affect the result of rest of the structure ?

 

Thanks

[peteroznewman]

You don't normally set the density to 0 when using acceleration. You don't need to do that to apply the acceleration to the point mass. 

Another student once asked how they could apply acceleration to just one part in an assembly and that is the answer.  If you have no need to do that, don't do it as it will affect the rest of the structure.

[deepesh.p.gurdasani]

1 )Thanks for your answer sir. Also, is there any setting specified by ANSYS that allows for acceleration to be scoped to a point mass if density set to zero because I am unable to see acceleration's position getting changed to that of point mass. Just curious to know if it is a trial and error method or there is procedure for it given by ANSYS.

2) In APDL also, there is no direct way of scoping acceleration to a part or point mass ?

 

Thanks

[peteroznewman]

Acceleration loads are applied to all mass in the model.  They are not scoped to individual bodies.  It doesn't matter where the label for the acceleration shows up.

APDL and Workbench both support an Acceleration load.