Reply To: Ball Bearing Transient Structural

[dlooman]

My personal opinion is that it is impractical and of little value to analyze the actual rotation of the needle or ball bearings.  Finite elements can only be rotated two or three degrees per time step.  You mention an inner race rotation velocity of 1000 RPM.  That 6000 degrees per second.  In the video the needle bearings are rotating around 10 times faster than the race so 60,000 degrees per second.  That will dictate a time step of no more than 2e-5 seconds.  As the contact is constantly changing the solution will be highly non-linear.  It's not impossible to do, but very time-consuming and tricky.  For example, if you want to simulate the steady state condition you would need to specify initial rotational velocities for the inner race and the needles/balls.  That's not possible through the gui.  What result are you hoping to find about the bearings?  If you are just practicing your FEA skills, try rotating a single body at 60,000 deg/sec.  Even that will not be trivial.