Influence of roughness filters in the analysis of elastohydrodynamic and dry circular contact

Resumo

Surface finishing and roughness parameters can directly affect the system’s efficiency and components’
useful life of several mechanical applications. In order to evaluate these parameters’ influence, one can employ
numerical methods that predict the pressure field and maximum contact pressure. The problem assessed in this
study is that, despite surface roughness being an “intrinsic” surface property, measured roughness is “extrinsic”
meaning that instruments using different sampling intervals and filters produce different asperities distribution,
which can affect the pressure field predicted by numerical modelling. Therefore, this study employs two numerical
models, a Dry Circular Contact (DCC) model and an Elastohydrodynamic lubrication (EHL) model to investigate
filtering influence over the maximum contact pressure. The results show that the same surface filtered with
different cut-off lengths presents distinct pressure fields and maximum pressure values. Also, the simulations
indicate that smaller cut-offs tend to produce higher pressures.