Validation of a FTIR Spectroscopy Method for Measuring and Monitoring Fuel Dilution in Lubricating Oils

摘要

A FT-IR based fuel dilution analysis system was validated for long term reliability and precision. Frequency shift and spectral reproducibility tests showed that the instrument could operate for up to 10 months without maintenance. Changes in ambient temperature and humidity levels and the proximity to mechanical and acoustic noise generators did not affect the performance of the instrument. This was accomplished due to the methodic analytical procedures, data analysis and isolation devices developed and employed. The system was calibrated using actual used oils and fuel dilution values determined by the standard ASTM Gas Chromatography method. The calibration model developed with multivariate algorithms was able to predict fuel in SAE 30, 40, 50 and Mil-L-9000 engine oils down to 0.4% dilution.