Sven Anteunis

Cosmos defining loads and constraints

Discussion created by Sven Anteunis on Apr 1, 2009
Hi everyone,

My company is designing windturbines of 600kW. For our certification process, we need to do a series of FEA analyse. Currently i am working on the tower structure.

As some of you know there is a yaw bearing mounted on the tower top. The surface of the towertop which makes contact with the bearing, needs to be constrainted in a way that the entire surface can tilt or move horizontly and/or vertically. So no local deformations.
The tower bottom is fixed.

For the loads working on the towertop, i need to define a moment which will work on that constrainted surface. The points which lare located far from the axis have to suffer more stress than the ones closer to the axis. It looks a bit like a bearing load, but that the force is higher as we move to the vertical plane.

Can please somebody help me to explain me if I need to define a constarint plane and conect the surface at the towertop to this. By doing so simulated a constrainted surface? When i tried this approach Cosmos declared that i cannot implement a force/moment on constrainted surfaces...

Pls help

Thank you in advance!