AnsweredAssumed Answered

Very confusing results from bearing Fixture

Question asked by Ed Frost on Apr 12, 2019
Latest reply on Apr 12, 2019 by Bill McEachern

Hi all,

 

I'm hoping you can help me in simulating some forces on a small UAV propeller:

 

I have a small vertical force (lift of 3N), an even smaller torque force, and a centrifugal force of 11,100 RPM, all acting around a bearing fixture shown at the base of this post.

 

This simulation ran perfectly for a very similar propeller design, with the exact same setup, but on this design it will simply not work. I know there are a lot of caveats with bearing fixtures so hopefully someone can tell me what I'm missing. Without the "self-alignment" ticked I get a very high stress (4.05e+05 MPa!) on a random part of the trailing edge (shown below) and with it ticked I get (less) excessive stresses in the bearing joint itself.

 

I get the warning about excessive displacements, but I understand the large displacement setting doesn't work for bearing joints. I don't know why I'm getting large displacements anyway as the forces are very small. Most confusing is that the exact same study worked fine on a similar propeller design (I can post those images if that's helpful).

 

Really appreciate anyone taking the time to help, I'm new to the forum and really impressed with how helpful everyone has been so far!

 

Thanks

 

Ed

 

 

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