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Nodal velocity as boundary condition

matparta

Mechanical
Apr 24, 2023
4
Hello
I am interested in an harmonic analysis (frequency response) of a structure made of a mass connected to a frame. The mass can be modeled as a point mass, connected with rigid constrains (or distributed coupling) to the frame, which is modeled by shell elements.
I want to apply a velocity on the mass as a nodal boundary condition - in other words, I want to simulate a mass moving with given m/s at given frequency(ies) and I want to see the vibration velocity in a certain part of the frame.
Now, the FE softwares that I have checked do not have the possibility to apply such as boundary conditions (Ansys and Actran - Actran seems to be able to do it but it is cumbersome). I can only apply nodal displacement boundary conditions or nodal loads.
Why is that? How would you approach the problem?

I thought about converting the velocity to an acceleration and by knowing the mass of structure connected to a frame, convert that to a point load applied as a nodal load.
Thanks
 
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why not turn it into a displacement at each frequency w using v=j*w*d?

It almost sounds like a forced response than a FR.
 

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