Solver Pivot Error Help!

- May 25, 2020 at 5:43 am
  
  franciscor
  Subscriber
  
  I am having trouble running a simulation of a wheel hub in Ansys it appears that my model is not properly constrained but I can't find a way to fix it, I have attached the project file.
  
  https://drive.google.com/file/d/1nYdN3zc-Uvvbk6M7kpt5AUXj2znqfhMn/view?usp=sharing
  
  Thank you very much for you help.
- May 25, 2020 at 4:22 pm
  
  peteroznewman
  Subscriber
  
  You have not put the correct files in the archive. Please follow these instructions for sharing your model using the Archive file.
  
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- May 25, 2020 at 5:26 pm
  
  franciscor
  Subscriber
  
  Understood thank you I have attached it in the format as indicated in the link, I am having difficulty locating where the constrain issues are that is why I did not attach screen shot although I believe the problem it is in the bolts.
  
  https://drive.google.com/file/d/1ScMgD83rEIQkA4l0stXJDeAm0fVr6AlG/view?usp=sharing
  
  Thank you for your help I apologize if the mistake is obvious but it is my first time using this program and our faculty is not being very helpful assisting us in the pandemic.
- May 26, 2020 at 1:18 am
  peteroznewman
  Subscriber
  The pivot error is because you are only applying forces and you don't have any supports.
  - You need to select one or more faces to restrain six degrees of rigid body freedom.
  - It could be the A and F faces are the supports and the bolts apply the force.
  - Or it could be the bolts that are the supports and the A and F faces apply the force.
  - The Reaction Force needed at the supports is calculated in the solution.
  Looking at the problem more broadly, this part and the bolts are not a very accurate representation of the loads on the part. To do a better job, you should bring in the part on the other side that the bolts go into, and the wheel section that the hub is clamping to that part. Then you would use frictional contact and bolt pretension to actually clamp the wheel, then you can apply the load to the wheel and support the other part. The stress in the hub will then be properly represented.