2 Replies Latest reply on Mar 17, 2012 6:59 PM by Michael Blair

    Modeling Stresses in Auger

    Michael Blair

      I am having some trouble setting up the forces and constraints in a model for an auger I am working on. The auger is going to be mixing a substance and it was found that it needs 60 in-lbs of torque to move at the desired speed. I want to model the situation in order to look at the stresses in the shaft. This is what I have so far:

       

      http://i.imgur.com/5n9tn.png

      http://i.imgur.com/k0Dj8.png

       

      In the first link I constrained the model at the top face (although there is a small hole near the top which a shear pin will be placed. Not sure if I should constrain it on that inside face instead?). The second image shows a closer view of the forces I have put onto the model. Since the auger blade is split up into two different directions, I figured I needed to put two forces on the faces of the blade depending which way the fluid was pushing on it. I also added a torque to the bottom face of the model. Would this be a correct setup for the situation? I am also unsure of the forces I should be putting on the faces of the blades. I'm not sure if putting the same force on the entire face is a correct way to do it.

        • Re: Modeling Stresses in Auger
          Paul Kellner

          Why did you put a torque on the bottom face of the shaft?

            • Re: Modeling Stresses in Auger
              Michael Blair

              I figured since I knew the torque required, putting it on the bottom face wouldn't be too bad of a model, although I was getting some questionable results. I have been looking at other scenarios, however, and I found that I could put the torque on the actual faces of the blades, which seems to give a more logical answer. I just want to make sure to take into account the stresses put into the shaft as well as the stresses at the connection between the blades and shaft, which is why I need the forces normal to the blades.