Análise de um pré-tratamento de dados baseado em valores limiares de amplitude na textura de superfícies brunidas

Abstract

The piston, piston-ring and cylinder liner assembly can be considered as one of the most important function groups for internal combustion engines, due to the fact that is totally related to the power produced from the combustion process from a thermal operating cycle and at the same time the energy losses, especially by friction, which are caused by the contact of the piston-rings with the cylinder and / or cylinder liner. One of the main demands of the automobilist industry and of industrial generators is the reduction of these losses by friction, in order to improve the efficiency of operation, as well as to reduce fuel consumption and to meet the emission levels of pollutants that are required by the Regulatory agencies. In this way, the mechanical contact of this mechanical unit is shown to be of scientific relevance, where the current mechanical contact models (Greenwood and Williamson, for example) bring as premise surfaces that have a distribution of Gaussian behavioral heights. Thus, the objective of this work is to analyze a pretreatment based on threshold values, for peaks, when applied to surface topography and its effect on the distribution of heights and statistical symmetry of the same, and also the comparison between the use of Gaussian filters on surfaces with and without the threshold cut-offs of roughness amplitudes.