Theoretical elastic stress singularities... much maligned and misunderstood

Singularities are invariably present in engineering simulation models due to the idealisations used for geometry and transitions from one material or thickness to another. As will be shown they are locations where the elastic stress is infinite, or tends to infinity with mesh refinement in some discretized idealisations. It will be emphasized that the singularities are also theoretical in nature as they cannot exist in practice. Despite the idealised nature of such singularities however, it is argued that a better understanding of their characteristics will allow them to be handled in an appropriate way in modelling and could also provide better insight into their use in making design choices and for the development of assessment procedures. Given that these are the likely locations of highest stress in any finite element idealisation, such an understanding should also prevent the misuse of stresses at such locations.