Three-dimensional fractal model of normal contact damping of dry-friction rough surface. (March 2017)

• Record Type: Journal Article
• Authors: Pan, Wujiu; Li, Xiaopeng; Guo, Na; Yang, Zemin; Sun, Zhaoning
• Is Part Of: Advances in mechanical engineering. Volume 9:Number 3(2017:Mar.)
• Publication Date: 2017-03
• Subjects: Dry friction -- joint surfaces -- normal contact damping -- three-dimensional topography -- fractal theory; Mechanical engineering -- Periodicals; 621.05
• DOI: 10.1177/1687814017692699
• Languages: English
• ISSNs: 1687-8132

Abstract

According to the influence of the normal contact damping of joint surfaces on the dynamic characteristics of high-precision machinery (machine tool, robot, etc.), in this article, a three-dimensional fractal model of normal contact damping of dry-friction rough joint surfaces based on Hertz theory and fractal theory is established. The three-dimensional surface topography is constructed, according to the modified double variable Weierstrass–Mandelbrot function. The fractal model of strain energyE e, dissipated energyE p, damping loss factorΔ, and normal contact dampingC n are deduced in detail, and the influence of fractal parameters and dynamic friction coefficientμ on them are simulated. The simulation curves show that strain energyE e, dissipated energyE p, damping loss factorΔ, and normal dampingC n increase with the increase in the fractal roughness G ; the influence of fractal dimension D onE e is more changeable, firstE e decreases with the increase in D and then increases.E p, Δ, andC n increase with the increase in D andμ, respectively; the effect ofμ onE e is not obvious, so simple change inμ has no significant change inE e ; a comparative analysis of the theoretical calculation of normal damping and experimental results show that their general trend is consistent, and they increase with the increase in total normal contact load P, the relative error is 5%–25%. The theoretical model can provide reference for the design of normal contact damping of the joint surfaces.