Integration of Photoacoustic Innova Analyzer Within Bag Bench for Direct Measurement of Ethanol in Vehicle Emissions

Ethanol fuel is a sustainable energy resource intended to provide a more environmentally and economically friendly alternative to fossil fuels. Ethanol fuel for automotive applications is becoming increasingly widespread and its market is continuing to grow. Measurement of ethanol was traditionally done with an impinger and a gas chromatograph (GC) system but this method is not a direct measurement, usually requires manual handling and takes a long time for post processing of data. The Innova photoacoustic analyzer can directly measure the ethanol emissions in vehicle exhaust without using the impinger/GC system.

For the past eight years at Chrysler, the Innova has been used as a stand alone analyzer and the emission sample bags were physically transported to the chemistry lab for ethanol measurement. The data had to be manually entered and post processed for the final results.

This paper describes the integration of the Innova analyzer within the emission bag bench at Chrysler for direct measurement of tailpipe ethanol exhaust emissions. Hardware and software modifications from the installation process are explained. Comparative testing was performed between the bench integrated analyzer and a stand alone analyzer. Testing was conducted on different vehicles with different emission levels and at different ambient temperatures. Fuels with different ethanol content (E20, E60 and E85) were also tested. Variability of the data is discussed.