The Brazier Effect and its Influence in the Design of Beampipes for Particle Colliders

The Brazier effect describes the influence of ovalisation on the buckling of thin shells. Ovalisation can be enhanced by applied bending moments and internal or external pressure. This can limit the design of vacuum chambers, requiring the addition of supports or changes in wall thickness. Since this is a non-linear effect, finite elements packages can fail to give good results. A theoretical and empirical approach is performed showing the results and conclusions of the tests.