Hi,

I can't get my analysis of two spur gears working properly. I have a model of simple spur gear that I inserted into assembly as two instances and manually positioned both of them so that they can come into contact. Initially they are separated because I couldn't achieve contact between them without intersection. Remote displacements were used to constrain the hubs. One gear has only rotation around its axis free and the other has prescribed small angular displacement or torque (I tried both) in this direction. I defined no penetration contact set between meshing teeth. Of course mesh was locally refined for these teeth. Here's how the model looks like (I highlighted contact surfaces):

The analysis always switches to direct sparse solver. But the problem is that it either hangs at 27,3 % or shows incorrect results: unphysically high stress, deformation of tooth on the opposite side than the one contacting the other gear or contact stress localized in very small areas (only at the front and back of the gear).

I also tried 2D simplification but it doesn't work properly as well. I'm not sure how to constrain the model in this case since remote displacements can't be used in 2D. I also can't apply torque or prescribed rotation to the edge of the hub. This model is either underconstrained or shows incorrect deformation (for the case below the right gear expands radially for some reason). Here's how this model looks like (again with highlighted contact regions):

Do you know what mistakes I make and how I should fix this analysis so that it solves properly ?

Thanks in advance for help