An innovative carbon-atom-balance-based method for diesel particulate measurement

This paper describes an innovative carbon-atom-balance-based method for die sel particulate measurement using a single non-dispersive infrared CO2 sens or. The diesel particulate sampler (DPS) uses two integrated steps of opera tion, i.e. collection and analysis of diesel particulate. In the collection operation, the diesel exhaust is channelled through a heated sampling line to a quartz filter where soot particulates, unburned hydrocarbons, water v apour, etc are trapped. Upon completion of particulate collection, the DPS system is isolated from the surroundings. This is followed by an analysis o f the diesel-particulate sample by either one of two analysis modes, namely , the regular and ramp modes. In the regular mode, the quartz filter is hea ted at a constant temperature for a defined dwelling period. Multiple sessi ons of heating at constant temperatures with individual dwelling periods ar e allowed for each analysis. In the ramp mode, the temperature controller i s programmed to achieve a specified heating rate. The lowest possible rate is 2 degrees C min(-1). Some preliminary results, in terms of mass concentr ations of particulates, were obtained from engine emission sampling using t his DPS system.