Inverse problems for elastohydrodynamic models

Inverse coefficient problems for variational inequalities arising in the el astohydrodynamic lubrication of a journal bearing are presented. The height of the gap between two rotating surfaces denotes the distributed parameter that has to be identified from estimates of Me pressure in the lubricant b etween the surfaces. The variational inequality approach which includes the phenomenon of cavitation, i.e. the situation where the gap is not entirely filled by the lubricant, reduces to the Reynolds lubrication equation unde r fully-flooded conditions. Utilizing a regularized least-squares formulati on the problem of existence of multipliers, and the importance and derivati on of a first order characterization amenable for (structured) numerical re alization are addressed.