AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
An Investigation of How Well Aerosol Instruments Estimate Solid Particle Number and PM Mass in Vehicle Emissions
MATTI MARICQ, Ford Motor Company
Abstract Number: 436 Working Group: Combustion
Abstract Recent LEVIII, Tier 3, and EU6 regulations have dramatically increased the stringency of PM and PN emissions standards. Developing new engine technology to meet these standards requires measurement tools with higher capabilities than prescribed in the regulations. To meet the combined targets of CO2, HC, NOx, and PM emissions, as well as many other design targets, the development engineer really needs more detailed information: when in the cycle do the emissions occur, are the particles solid or liquid, how large are they, etc.?
New PM instruments have been developed with the combustion engine community in mind. Three seeing significant use are: the Dekati Mass Monitor (DMM), the Engine Exhaust Particle sizer (EEPS) / DMS500, and the Micro Soot Sensor (MSS). These provide mobility/aerodynamic, electrical mobility, and optical absorption measurements of the PM respectively. Furthermore, with suitable assumptions their data can be converted to estimate particle number and mass emissions.
Separately, or in combination, these instruments provide significant useful information to help guide engine and aftertreatment design. None follow the regulatory definition of PM or PN, but it is possible to derive from them the regulated quantities. The present work examines the performance and inter-relationships of these instruments, as well as filter based PM mass and solid particle number, for about 35 tests done with 7 vehicles. The vehicles range from a diesel emitting an order of magnitude above current standards, several gasoline direct injection vehicles with varying emissions levels, and a PFI vehicle with emissions at ~1 mg/mi. This study examines instrument performance for the FTP drive cycle, where sensitivity and artifacts are a concern, as well as for the US06 drive cycle, where interferences arising from the aggressive nature and high exhaust temperature associated with this cycle are a concern.