ALDEHYDE EMISSIONS FROM AN ETHANOL-FUELLED SPARK IGNITION ENGINE: SIMULATION AND FTIR MEASUREMENTS

This paper presents a mathematical model which calculates aldehyde emissions in the exhaust of a spark ignition engine fueled with ethanol. The numerical model for aldehyde emissions was developed using FORTRAN software, with input data obtained from the engine cycle simulated by the commercial software BOOST. The model calculates formaldehyde and acetaldehyde emissions, formed from the partial oxidation of methane, ethane and unburned ethanol. The calculated values were compared with experimental data obtained by Fourier Transform Infrared Spectroscopy (FTIR). Tests were performed with a mid-size sedan powered by 1.4liter spark ignition engine on a chassis dynamometer. In general, the results demonstrate that the concentrations of aldehydes and their producers increased with engine speed and exhaust gas temperature. There was a good agreement between simulated and measured values.