Transient Particulate Emission Measurements in Diesel Engine Exhausts

This paper reports our efforts to develop an instrument, TG-1, to measure particulate emissions from diesel engines in real-time. TG-1 while based on laser-induced incandescence allows measurements at 10 Hz on typical engine exhausts. Using such an instrument, measurements were performed in the exhaust of a 1.7L Mercedes Benz engine coupled to a low-inertia dynamometer. Comparative measurements performed under engine steady state conditions showed the instrument to agree within ±12% of measurements performed with an SMPS. Moreover, the instrument had far better time response and time resolution than a TEOM^® 1105. Also, TG-1 appears to surpass the shortcomings of the TEOM instrument, i.e., of yielding negative values under certain engine conditions and, being sensitive to external vibration.