Analysis of the fluid pressure, load capacity, and coefficient of friction of an elliptic machine hammer peened surface structure in hydrodynamic lubrication

Recently, the velocity distribution within an elliptical machine hammer peened (MHP) surface structure was discussed by solving analytically the Reynolds equation using Full-Sommerfeld boundary condition (Trauth et al. in Tribol Lett 60(19):1–13, 2015). However, in order to design the MHP process to obtain defined friction characteristics and load capacities of a fluid film, the pressure distribution has to be analyzed as well. Thus, in this contribution, the fluid pressure is discussed using Full-Sommerfeld first, then the previous work is extended by the Swift–Stieber boundary condition to account for cavitation effects. Thereby, the influence of geometry and process parameters on the fluid pressure, load capacity and coefficient of friction will be analyzed both using an approach based on absolute and dimensionless numbers. To asses the influence of lateral effects, the semi-analytic 1D results are compared to numerical 2D results based on the Raimondi approach. Thereby, a recommendation for a surface design manufactured by machine hammer peening is formulated.