Multiple Solutions in Dynamic Contact Problems With Friction

A frictional force resists the relative motion of the two surfaces. An understanding of the difference between static and dynamic contact with friction can lead to methods, which reduce friction and wear. The main goal of the present work is to evaluate the various solutions for the dynamic contact problem with friction and to compare theirs with the solution of the static contact problem. Another goal of the present work is to clarify whether the perturbation of some problem parameters during sliding with time can lead to the difference between solutions of the static and dynamic contact problems with friction. The essential parameter determining friction is the number of asperities in contact. The number of asperities in contact changes as a consequence of the wear. As follows from the classical wear models the perturbation frequency of the number of asperities in contact depends on the sliding velocity. The model of dynamic contact with friction based on the perturbation of the number of asperities in contact, along with the alternative models, is discussed in the present work.