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Torque and Thrust on a Shaft

Question asked by Bjorn Sorenson on May 2, 2014
Latest reply on Jul 24, 2014 by Jared Conway

I'd like to analyse torque and thrust on a vertical shaft at the same time.  I've set up the problem for torque-only using an "on cylindrical faces" fixture to simulate the bearings (see attached; torque at 1 is equal and opposite to total torque at 2 & 3) and gotten good results.  What I'd like to do is apply (in addition to the torque force) a thrust force located at points 2 & 3 as indicated in the image.

The problem I'm running in to is that the "on cylindrical faces" fixture won't transmit the bending moment through the fixture, and a bearing fixture won't transmit the torque unless I know the axial and radial stiffness values of the bearings.

I might be able to get axial stiffness values from the bearing manufacturer, but radial stiffness seems very non-trivial (it is based on the bearing/lubrication itself, RPM, angle of the deflected shaft running through it, etc.).  Simulation will allow me to define a flexible bearing with just axial stiffness, but I don't feel comfortable leaving radial stiffness out of the equation altogether.  Any suggestions?

I should also note that I'm not set on using the SW Sim bearing fixture if there's a better way to do this.  Any and all input is appreciated!