maximum rotor speed

- June 19, 2020 at 12:44 pm
  
  Christian10
  Subscriber
  
  It is possible to determine the maximum rotor speed of a machine with the static mechanical analysis. If so, what do I have to set? I can't find any..
  
  Best regards,
  Christian10
- June 19, 2020 at 1:35 pm
  Wenlong
  Ansys Employee
  Hi Christian,
  
  What are the constraint conditions to determine the max rotor speed? If you can share more information about the physical problem it can let others better help you.
  
  This is a rotordynamics analysis and this document can help you get started. https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v201/en/ans_rot/Hlp_G_ROTINTRO.html
  
  Let me know if you have more questions.
  
  Regards,
  
  Wenlong
  
  ================ Note ====================
  
  If you have trouble opening the links I attached, please see the first useful link below
  
  Useful Links
- June 22, 2020 at 5:55 pm
  
  Christian10
  Subscriber
  
  Hello Wenlong, thanks for your message, unfortunately I cannot open your link, because I only have the "student license"...
  
  Attached I send you a picture, where you can see the my Rotor. As settings I have chosen two different materials, for rotor - steel and for the magnet neodymium.
  
  I can tell you the following about the geometrical boundary conditions. In point A (picture) there should be a boundary condition which prevents the displacement in vertical direction, but I have not found the right one yet. In point B there should be a frictional contact point between magnet & rotor. But Ansys throws me a mistake if the coefficient of static friction is above 0.2... In point C I have chosen a fixed bearing on the surface. Otherwise I have chosen a rotation speed as inertial load, which rotates around the own axis of the rotor.
  
  The maximum rotational speed would have to be adjustable somehow and would inevitably depend on the material yield point of the rotor, i.e. steel.
  
  Now I hope that you can get a better picture with this information. Unfortunately, I am still quite new to Ansys and maybe I have explained it in an incomprehensible way.
- June 22, 2020 at 7:17 pm
  
  peteroznewman
  Subscriber
  
  How to access Ansys Online Help Document
- June 23, 2020 at 7:06 pm
  
  Wenlong
  Ansys Employee
  
  Hi Christian,
  
  Thanks for your explanation.
  
  If you want to involve frictional contact, which is nonlinear, then you cannot run a rotordynamics because only linear behavior is allowed in rotordyanmics . The transient Structural Analysis will be the choice for you in this case.
  
  I don't think Static Structural Analysis is suitable for your case because the dynamic effect needs to be considered.
  
  Your error (when COF>0.2) is probably due to a convergence issue. Please make sure you turned on large deflection and have defined enough substeps. Also, remember to turn on the Coriolis effect in "rotordynamics controls".
  
  If you have further questions, please feel free to follow up.
  
  Regards,
  
  Wenlong