Procedure for engine transient cycle emissions testing in real time

In this study, a procedure was applied for the performance of real-time emissions measurement at engine transient tests. The measurement of gaseous emissions from raw exhaust was done according to the standard ISO16183:2002 and the particulate mass emission was determined by an alternative method based on the measurement of smoke opacity and hydrocarbon emission during the transient test for further conversion to particulate mass. The method for calculating particle mass was validated by comparison with experimental data obtained by application of the standard gravimetric method. A measurement strategy, including engine preconditioning and control of ambient temperature, was applied to improve measurements. For the analysis of results, the time misalignment of the measurements was corrected by the calculation of the delay times produced as a result of the measurement systems configuration. The measurement procedure was applied to two cases of cycles UDC: with and without glow plug inside the cylinder of a light duty Diesel engine. The time evolution of each pollutant was analyzed to get understanding of which stages of the cycle produce more pollution and the comparison between both cycles was done by using the exhaust emissions integrated during the tests. (C) 2005 Elsevier Inc. All rights reserved.