3 Replies Latest reply on Feb 24, 2011 11:00 AM by Anthony Botting

    APPLY A FORCE

    Apostolos Lilias

      HELLO

      MY QUESTION IS HOW I CAN APPLY A FORCE ON THE CENTER OF GRAVITY OF A PART. THE GRAVITY FORCE IS APPLIED TO THE CENTER OF GRAVITY OR IS ADISTRIBUTED FORCE?

      THANK YOU

        • Re: APPLY A FORCE
          Anthony Botting

          Hi Apostolos. Just use the "gravity" option in the Loads property Manager. The answer to your second question is "yes" and "yes". The gravity force is effectively applied at the CG, but technically it is distributed to every single node of every element according to each element's mass. If an element has mass "m" and four nodes, then the force at each node is mg/4 (for that node, more if it's connected to nodes of other elements) in the direction of your gravitational acceleration. Hope that helps. -Tony

            • Re: APPLY A FORCE
              Apostolos Lilias

              HELLO ANTONY

              I AM TRYING TO FIND WHERE IS THE GRAVITY OPTION IN LOADS PROPERTY MANAGER. WHEN I AM SELECTING GRAVITY FOR SECOND TIME I HAVE THE MESSAGE THAT GRAVITY ALREADY APPLIED. I WANT TO APPLY A SECOND FORCE EXCEPT FROM GRAVITY

                • Re: APPLY A FORCE
                  Anthony Botting

                  Hi Apostolos: I'm certain you can add another acceleration vector if you edit definition on the "Gravity" load (there should be an "Advanced" double-pointing arrow to open more options). In there, are two other directions of which you can assign a unique acceleration value to effectively act at the CG of the model. Another idea (thinking out-loud)  is to add a "Remote Load", but you need a location on which to attach the load. You might be able to cut-out a small sphere void at the CG location, and replace it with an actual sphere of the same size and appropriate density of the removed material. Make sure bonded contact will secure the sphere. Then, apply a remote load to the sphere surface. You could hide the rest of the model to allow selection of the sphere surface for Remote load application, or use the "select-other" command to locate the sphere surface. Gee, maybe I'm "reaching' a bit here!  -Tony