A method for determining the masses concentrations of harmful substances in the exhaust gases of internal combustion engines

摘要

Determination of pollutant concns. in exhaust gases esp. of automobile engines under various running conditions is carried out by mixing exhaust gas and air to produce a dilute exhaust gas stream of homogeneous compsn. and temp. and then subjecting the stream to constant vol. sampling and analysis of pollutant types and concns. The novelty comprises (i) measuring the respective volumes of undiluted exhaust gas and/or diluent air in successive time intervals (e.g. of 1 sec.); (ii) determining the prevailing dilution ratio for each time interval; and (iii) determining, using these dilution ratios, the pollutant concns. in the undiluted exhaust gases by computation from the pollutant concns. measured in the diluted exhaust gases. ADVANTAGE - The process allows dynamic measurement of pollutant emissions according to type and concn.