MÉTODOS MULTIVARIANTE EN ESPECTROS FTIR PARA LA DETERMINACIÓN DE LA VISCOSIDAD CINEMÁTICA Y EL NÚMERO ACIDO EN ACEITES DE AVIACIÓN

Abstract

The multivariate techniques can represent an alternative, fast, easy, inexpensive and non-destructive to determine physicochemical properties of oils in service in aircraft internal combustion engines (MCI), such as kinematic viscosity and acid number which determine the end of their useful life. Numerous studies have been performed in lubrication systems operating in other fields, but this sector requires to assess quickly and expeditiously the lubricant condition in order take preventive and corrective measures stated in Condition Based Maintenance programs. One of the mathematical methods for the calculation of concentrations and properties from instrumental data of chemometrics, is the method of Partial Least Squares PLS, strongly related to Principal Component Regression PCR that can take into account infrared spectrometry. Real values obtained were correlated to each property with the infrared spectra and multivariate analysis techniques applying PCR and PLS (PLS1 and PLS2) for a sample of 50 oils in engine operation. The results obtained show that the studied multivariate methods have the potential to estimate both properties.