CRC Correlation of Diesel Smokemeter Measurements 690493

Diesel smoke measurements were made over a broad range of smoke intensities with seven different commercially available smokemeters using a 4-cycle engine and a 2-cycle engine operated under steady-state conditions on two fuels of different smoking tendencies. Exhaust soot concentrations were also measured by two filtering methods, and smoke was rated visually by two trained raters. Correlations among the smokemeter readings did not differ with either fuel or engine. A nomograph correlating smokemeter readings was prepared, and agreement with published data appears generally good except for high readings from one continuous filtering smokemeter exposed to high sampling pressure, and unexplained low readings from a light-dispersion meter. The CRC Smokemeter Group believes these correlations, with the exceptions mentioned, give a firm basis for comparing measurements made with different smokemeters.