2 Replies Latest reply on Dec 2, 2010 7:14 PM by Anthony Botting

    DIFERENCE BETWEEN FIXED HINGE VS BEARING FIXTURE

    Apostolos Lilias

      Hi

      I am having one shaft which is supported in two positions and it is loaded with a remote load. The problem that I have is when I am simulating the shaft using fixed hinge fixture the reaction forces on the supporting faces are different from the case that I am using bearing fixture and I cannot understand why this happening. Also when I am using bearing fixture the reaction force is zero and I can have only the free body forces. If I will allow alignment for the bearing fixture then I have reaction forces but also I have reaction moment which is not correct. With the hinge fixture I have both reaction and free body forces which are the same magnitude both, but different with the forces of bearing fixture. I want to know which is the right fixture. Can somebody give me a help about this.

        • Re: DIFERENCE BETWEEN FIXED HINGE VS BEARING FIXTURE
          Ryan Werner

          To view results for the Bearing Fixture Right Click on the Results folder and select List Pin/Bolt/Bearing Force.  This will give you the forces that the bearing is seeing.  If you are restraining the outside cylindrical surface of a shaft tha twould be supported in a bearing than the Bearing Fixture is the better choice.  Looking up the two different restraints in help can also give you a better description of how the actual model is restrained and may help you determine which better meets your needs.

           

          Ryan W.

          • Re: DIFERENCE BETWEEN FIXED HINGE VS BEARING FIXTURE
            Anthony Botting

            The term used in the Simulation Fixtures "Fixed Hinge" has always sounded like an oxymoron to me, but I know the software applies a radial restraint=0 and an axial restraint=0 to the nodes of the selected entities. The restraint effect is supposed to be similar to what you might see on a door hinge. The bearing fixture is a modification of that: it allows for stiffness input in radial and axial directions for some flexibility to ground (whereas the fixed hinged is rigid with respect to ground). Hope that helps a little.