NUMERICAL-SIMULATION OF THE EFFECTS OF 3-DIMENSIONAL ROUGHNESS ON HYDRODYNAMIC LUBRICATION - CORRELATION-COEFFICIENTS

Numerical simulations of the lubrication of rough surfaces have been d one using the Finite Element Method. Only pure pressure flow condition s have been considered. The correlation coefficient between pressure a nd height, pressure and height gradients etc. are presented for two di fferent isotropic surfaces. For comparison, one slightly anisotropic s urface and one surface with pure transverse roughness have also been i nvestigated The three-dimensional surface roughnesses have been produc ed numerically using Finite Impulse Response (FIR)filters and FFT. The only two significant correlations are between the pressure and the he ight gradient in x-direction and between the height and the pressure g radient in x-direction. The correlation coefficients can be used to ap ply better boundary conditions when analyzing the lubrication of a rou gh bearing, and how this can be done has been roughly explained.