The Influence of Normal Pressure on the Friction Force Reduction Effect Caused by Longitudinal Tangential Vibrations

The article presents the results of experimental research and numerical analysis of the effect of normal pressures on the level of friction reduction caused by longitudinal tangential vibrations. The experimental characteristics of tangential compliance of steel-steel junction with specific roughness as a function of surface pressure are presented. The simulation tests were performed in the Matlab/Simulink environment. Dynamic friction models were used in the calculations i.e., the Dahl model and the elasto-plastic model. These models consider both the tangential compliance of contact and the phenomenon of presliding displacement. The experimental tests were carried out on a specially made test stand. Root Mean Square Error (RMSE) was used to assess the compliance of the results of numerical calculations with the results of experimental tests. It has been shown that the change of normal pressures has a significant impact both on the level of friction force reduction and the contact stiffness. For higher normal pressures, a better agreement with the experimental data is achieved by the elasto-plastic model.