﻿ Extended calculation model

MESYS Calculation Software

 Extended calculation model

The extended calculation model allows to define different elements for axial and radial contacts. Also it allows to consider clearance between bearing ring and shaft or housing. The clearance between bearing ring and shaft or housing is a result of the bearing calculation and it can optionally include elastic expansions of the bearing ring, if activated using Elastic ring expansion in the bearing calculation.

For each ring several options options available:

"No additional shaft for the inner/outer ring": The ring is connected to the shaft using a single central node like in the default model. Axial and radial forces are transmitted and no clearance (between bearing ring and shaft or housing) is supported.

"Additional shaft for inner/outer ring, axially free": An additional internal shaft is generated for the ring, which is axially free. In radial direction the clearance defined in the bearing calculation is considered. If there is a radial clearance the ring can also tilt based on clearance and width.

"Additional shaft for inner/outer ring with axial contact":   An additional internal shaft is generated for the ring and axial contact for both sides can be defined to either the same shaft as the radial contact a different shaft or to an adjacent bearing. The connected shaft needs to extend to the bearing ring. An axial clearance can be defined. Optionally an axial stiffness can be defined and a clearance to the block length of the spring. The spring is considered to act on the nominal ring diameter and reaction moment will occur on tilting angles. As before radial clearance as defined in the bearing calculation is considered.
If the ring is connected to an adjacent bearing ring a distance between the bearing rings is supported. A diameter for a spacer can be defined in this case which is assumed to have the same material and temperature as the right bearing.

If additional clearance is considered, convergence problems can occur if the system is not statically defined. A bearing without load and without preload can lead to convergence problems if clearance is defined between bearing ring and housing. This case is typically avoided in practice, because it could lead to a bearing damage. Therefore the extended bearing model should only be activated, if additional effects have to be evaluated, but not as standard setting.

If the extended calculation model with an additional shafts is used together with 3D-elastic parts, then only the radial contact may be of type  "elastic bearing" in the 3D-part. The axial contacts may only be single nodes defined with type "rigid" or "average".