2 Replies Latest reply on Oct 31, 2012 6:57 PM by Craig Poppe

    Displacement results don't match initial condition displacement

    Craig Poppe

      I am doing a linear dynamic simulation of a cantilever beam with the free end given an initial displacement. The issue I am having is that the resulting motion of the beam does not make sense with the initial displacement I applied. I've been using an initial displacement of 20mm, but when I look at a response graph of the UY displacement of a node at the free end, the range of motion is about +/- 0.02mm. I'm thinking that the initial displacement I am defining is not the same as the one I think I am defining, but I can't figure out what I am doing wrong. I choose an edge in the x direction  at the free end of the beam as the component I want to displace, and for the direction of displacement I choose an edge that is in the y-direction, at the fixed end of the beam. Does anyone know what I am doing wrong? Perhaps a useful clue is that I am also bonding a patch of damping material to one side of the beam, and as I change the position of this patch along the length of the beam, the displacement at the first timestep changes. It seems like this shouldn't happen since the initial condition displacement is always the same, and the impact of the different position of the damping material shouldn't make a noticeable difference after only one timestep. Attached is a picture of the setup.

       

      Thanks in advance for your response(s).